Original Research Article

Morphological diversity of Lasiodiplodia sp. isolates infecting woody and fruit crops in Côte d’Ivoire

  • Yaya Kone1
  • Akissi Sandrine Yao1
  • Adjoa Marie Josephine Kouadia1
  • Massiata Dagnogo1
  • Léon Etien Hamian2
  • Eric-Olivier Tienebo1
  • Kouakou Théodore Kouadio1
  • Kouabenan Abo1

1.    INTRODUCTION Fungal diseases pose a major threat to agricultural production in tropical regions, affecting both the quality and yield of woody and fruit crops [1]. In Côte d’Ivoire, crops such as cashew (Anacardium occidentale), mango (Mangifera indica), cacao (Theobroma cacao), and rubber (Hevea brasiliensis) are important sources of income for local producers. However, the productivity of these crops is frequently limited by fungal diseases, including those caused by Lasiodiplodia [6]. Lasiodiplodia spp. is a phytopathogenic fungus widely distributed in tropical and subtropical zones, responsible for fruit rot, twig dieback, and cankers on many woody trees [12]. This genus is distinguished by its high morphological and physiological diversity, influenced by the host species, growing environment, and agroecological conditions [8,11]. In Côte d’Ivoire, despite some studies on *Lasiodiplodia theobromae* in cocoa and mango plantations [3], knowledge of the morphological diversity, distribution, and pathogenic potential of isolates from different crops remains limited. Morpho-cultural and microscopic characterization of isolates is an essential tool for understanding the variability of fungal populations and adapting integrated disease management strategies [4,15]. Indeed, the diversity of traits such as mycelial growth, pycnid production, and conidia density and morphology can reflect the genetic variability of isolates and their ability to adapt to environmental conditions [14]. Thus, this study aims to evaluate the distribution and morphological and cultural diversity of Lasiodiplodia sp. isolates collected from different woody and fruit crops in Côte d’Ivoire, in order to provide useful information for disease management and the improvement of agricultural productivity. 2.    MATERIALS AND METHODS 2.1. Prospecting and sample collection Surveys were conducted during the production season in the main agro-ecological and agricultural production areas of Côte d’Ivoire. They covered several crops of economic interest, including cashew, mango, cocoa, cola, rubber, Accra Cone, and banana (Figure 1). Plant material exhibiting characteristic symptoms, including dieback, cracking with exposure of internal tissues, gummy exudations, and rot were collected in the field. A total of 281 samples were collected from several locations distributed across different production regions, depending on the crops studied (Table 1). The collection covered 96 locations for cashew, 50 for cola (Cola nitida), 38 for cocoa (Theobroma cacao), 34 for mango (Mangifera indica), 29 for rubber (Hevea brasiliensis), 11 for Accra Cone (Polyalthia longifolia), and 11 for banana (Musa acuminata), distributed respectively across 7 to 15 regions depending on the crop. Cocoa pods naturally affected by black rot were collected from different trees within each surveyed plot and individually packaged in labeled plastic bags (date, plot code, and sample number). The banana samples, harvested at physiological maturity, from industrial plantations were obtained in Zambakro, Abengourou, Tiassalé, Dabou, Béoumi, Azaguié, and Agboville. A detailed breakdown of the samples by crop, location, and region is presented in Table 1. The collected samples were kept in plastic bags and transported to the phytopathology laboratory of the INP-HB in Yamoussoukro. 2.2. Isolation and purification of fungi The isolation and purification of fungi were carried out in the laboratory according to protocols adapted to the plant organs studied. For stem samples, the method described by [19] was applied with slight modifications. Symptomatic fragments of mango, rubber, cola, Accra Cone, and cashew stems (≈ 1 cm) were superficially disinfected in a 50% sodium hypochlorite solution for 1 min, then rinsed three times with sterile distilled water before being placed on PDA medium amended with citric acid. The harvested bananas were washed, rinsed with sterile distilled water, and kept at 28°C. Ripening was homogenized by immersion in an ethylene solution (2 ml·L⁻¹) according to [9]. After lesions appeared, the fruits were disinfected with 70% alcohol, and fragments taken from the growth front were inoculated onto PDA medium. For cocoa, subcortical tissue fragments were collected from necrotic lesions of pods affected by black rot, after disinfection with 96% alcohol and flaming, and then placed on PDA medium [5]. Petri dishes were incubated in the dark for 3 days at 28 ± 2 °C. Isolates were purified by subculturing at the mycelial growth front [5]. 2.3. Laboratory identification The final stage of the study consisted of identifying the pathogens associated with fruit dieback and rot. Isolates were characterized based on morphological criteria, including macroscopic observation of colonies (color, general appearance, and presence of pycnidia) and microscopic examination of conidia (morphology, color, and size). Species identification was performed by referring to the descriptions and taxonomic keys proposed by [16]. 2.4. Morphological characterization of the isolates In total, 161 isolates representative of the different sampling areas were selected for the evaluation of morpho-cultural parameters. The study was carried out on three culture media: PDA, MEA and agar, prepared according to the protocols described by [18] for PDA and agar media, and by [13] for the MEA medium [8]. For each isolate, a 4–5 mm diameter mycelial explant, taken from the growth front of a 5-day-old culture on PDA, was placed in the center of Petri dishes containing the different media. Each isolate was subcultured into five dishes (replicates) and incubated at 28 ± 2 °C under a 12 h/12 h light/dark cycle, as described by [16]. Morphological and cultural traits were assessed based on mycelial growth rate, as well as mycelium color and texture. Radial growth was measured daily by drawing two perpendicular axes on the back of each Petri dish and then calculating the average of the two diameters until the dish was fully filled [7]. The average growth of each isolate was determined from the five replicates. The diameter (in mm) of each isolate was measured in two perpendicular directions, and the average colony diameter was calculated using equation 1. where D is the average diameter of the isolate in a box, d1 and d2 are the measurements of the two perpendicular diameters. Growth was measured daily until full culture expansion using equation 2: where CM is the daily mycelial growth rate, Ddn is the average diameter growth on the day of measurement. Dd0 = initial diameter of the mycelium disc, which is 5 mm [8]. The appearance of colonies and … Read more

Analysis of Cashew Tree Yield Variability at the Tree and Orchard Scales

  • Gabésongon Kone1
  • Abo Kouabenan1
  • Mariam Bognan Coulibaly2

Introduction The cashew tree (Anacardium occidentale L.), a perennial species belonging to the Anacardiaceae family, is native to northeastern Brazil. Widely recognized for the significant economic value of its fruit—the cashew nut—the species was introduced to Africa and Asia by the Portuguese [1]. Although initially deployed to combat soil erosion, it has since evolved into a major cash crop across West Africa [2]. This transition is driven by its high market value, the increasing organization of the value chain, and its vital socioeconomic role in rural communities. Currently cultivated in nearly all tropical regions, cashew nuts hold a strategic position in Côte d’Ivoire, which emerged as the world’s leading producer of raw cashew nuts (RCN) in 2019 [3]. By 2023, Ivorian production reached an estimated 1,225,935 tons, accounting for approximately 40% of global output [4]. The cashew tree plays a fundamental role in the socioeconomic landscape of rural populations in Côte d’Ivoire. Much like cocoa, its cultivation enables the northern and northeastern regions to bolster financial resources and improve access to essential education and healthcare services. Cashew farming is predominantly characterized by smallholder family farms, with plots typically ranging from 0.5 to 3 hectares. These systems frequently employ intercropping with food crops, a strategy that not only optimizes land utilization but also reduces maintenance costs; specifically, the expanding canopy of the cashew trees naturally suppresses weed growth. Revenue generated from the marketing of cashew nuts is further utilized to fund social ceremonies (such as weddings, funerals, and rituals), acquire consumer goods (including motorcycles and appliances), and invest in housing construction [5]. Overall, the cashew sector supports approximately 2.5 million Ivorians and contributes 7% to the national Gross Domestic Product (GDP) [5]. Despite its socioeconomic importance, the average yield per hectare remains relatively low, estimated at 620 kg/ha, which is significantly below the optimal potential of 1,200 kg/ha for raw cashew nuts (RCN). This yield gap is attributed to several factors, including insufficient agricultural investment, limited knowledge regarding input application, and a lack of proficiency in essential cultural practices, such as pruning. Previous studies have highlighted these challenges, emphasizing that specific agricultural behaviors and technical constraints directly contribute to the low productivity of orchards across the region [7, 8, 9]. Notwithstanding the alarming data on low yields, comprehensive knowledge of tree cropping systems in West Africa remains limited and fragmented. Whether at the micro-scale (individual tree) or the macro-scale (plot or production basin), available data are frequently imprecise, incomplete, or absent In Côte d’Ivoire, while cashew nuts occupy a strategic position in rural economies—serving as an essential income source for producers in the north and northeast—the crop’s potential remains largely under-exploited. This underperformance is compounded by high yield variability, which remains poorly documented at both the tree and orchard levels. A deeper understanding of this variability is therefore critical to identifying primary limiting factors and developing tailored agronomic interventions. In this context, the present study aims to analyze cashew nut yield variability at two distinct levels: the individual tree and the orchard. Specifically, the objectives are to: Research Hypotheses H1: Tree productivity varies significantly based on age and planting density. H2: Tree morphology (height, trunk diameter, and canopy diameter) is significantly influenced by both planting density and tree age. METHODS Materials And Methods This section details the resources and procedures implemented to conduct the study. It is organized into two primary components: Materials, which include a description of the study site, plant material, and measurement tools; and Methods, which provide a detailed account of the data collection protocols and statistical analyses. Study Site The study was conducted across 24 orchards in the Poro region (8°26’–10°27′ N, 8°26’–10°27′ W). Covering an area of 13,400 km², the Poro region is organized into four departments: Dikodougou, Korhogo (the regional capital), M’Bengué, and Sinématiali. The regional climate is Sudanese, characterized by a distinct dry season from November to April and a rainy season from May to October [10]. Annual rainfall typically ranges from 1,000 to 1,400 mm, with average monthly temperatures between 26.93°C and 27.02°C, peaking at approximately 36°C in March [11]. The vegetation is diverse, featuring Sudanese savanna in the northern reaches and sub-Sudanese savanna in the south. The topography is varied, with elevations such as Mount Korhogo exceeding 500 m. Soils are predominantly ferralitic, ferruginous, and hydromorphic, characterized by high permeability and porosity. The local economy is primarily driven by livestock and agriculture, including major cash crops (cotton and cashew) as well as food crops (yam, rice, and sorghum).  Materials This subsection details the equipment used, ranging from field data collection (morphological and yield parameters) to laboratory-based statistical processing. Plant Material The plant material consisted of cashew trees (Anacardium occidentale L.) located within 24 orchards delineated into study plots in the Poro region. Technical Equipment Cashew tree dimensions were measured using a decameter, while a graduated wooden pole was used for height measurements. Plot boundaries (2,500 m²) were established using ropes, and the seven selected sample trees per plot were marked with spray paint. For nut collection and measurement, harvest bags and a precision scale were used. Data (nut mass and quantity per tree and per plot) were initially recorded in field notebooks and subsequently digitized using Open Data Kit (ODK). Methods Orchard Selection To analyze cashew yield variability at both the tree and plot scales, four age categories were selected: 5, 10, 20, and 30 years. These categories were chosen to better understand yield fluctuations and tree physiological behavior over time. Data Collection Design A preliminary survey was conducted to assess orchard age and density. Consequently, the selection focused on these two factors. For each of the four age categories (5, 10, 20, and 30 years), three planting density classes were defined: Plot Establishment: Based on these criteria, 18 orchards were selected (2 orchards per density class × 3 density classes × 4 age categories — Note: Please verify if the total is 18 or 24 based on your math). Within each orchard, a 50 m × 50 m (2,500 m²) plot was established, and seven specific trees were monitored within each … Read more

Assessment of the Growth of Agronomic Parameters of Pumpkin (Curcubita pepo L.) to Rates of Poultry Manure

  • Onwubiko, G. N.
  • Okereke, C.S.

Introduction Vegetables are gradually acknowledged as crucial for food and nutrition security [22]. However, organic vegetables are increasingly preferable to many consumers as they are shifting their food choice priorities towards food they perceive to be healthier for themselves and the environment. Cucurbita pepo is a squash or pumpkin belonging to the Cucurbitaceae family and genus cucurbita that resembles a guard, with over 130 genera and up to 800 species [21]. In the agricultural industry, pumpkins are cultivated as vegetables on a large scale, contributing to the agricultural economy. The production and sale of pumpkins, whether for fresh consumption or processing into various products, generate revenue for farmers and the agricultural sector. They are processed into a wide range of food products such as pumpkin soup, pumpkin-based snacks, pumpkin pie filling, etcetera. These processed products contribute to the food industry’s revenue and provide employment opportunities in processing and manufacturing plants. The seasonal demand for pumpkins drives retail sales of fresh pumpkins, decorative pumpkins, and pumpkin-related products, contributing to the economy, especially in regions with a vibrant pumpkin culture. In some cultures, pumpkins are an important part of traditional dishes and celebrations, such as pumpkin pie in the USA, or pumpkin lanterns on Halloween. Pumpkin is a natural treasure full of health benefits, from its seeds to its flesh and even leaves; almost every part of pumpkin can be used for healing, nourishment, or even beauty. Pumpkin is highly nutritious and enriched in vitamins A, C, and E,  dietary fiber, and potassium [11]. Pumpkin is rich in potassium, which helps to balance the effects of so much sodium in the body. These nutrients support overall health and well-being, making pumpkins a valuable addition to a nutritious diet. The fiber in pumpkin aids absorption of sugar in the bloodstream thus regulating blood sugar levels, supports digestion, and relieves constipation ([6]. Their vibrant orange colour is indicative of their high beta-carotene content, which helps to improve eyesight and reduce the risk of eye diseases like night blindness and age-related macular degeneration. These carotenoids possess properties associated with a reduced risk of certain chronic diseases, such as cardiovascular diseases and certain types of cancer, and support immune function [17,23]. Also, cucurbitacins, a group of compounds found in Cucurbita pepo, reportedly possess anti-inflammatory and potentially alleviate symptoms associated with inflammatory conditions such as arthritis and certain autoimmune disorders [7]. Cucurbita fruit is low in calories and provides many advantages for human health, including blood cleansing, constipation relief, improved digestion, and energy production [9]. Cucurbita seed kernels have been employed as functional materials and nutrient supplements in baking, cooking, and ground meat compositions [25,13]. It has been observed that the seed extract possesses antioxidant, antitumor, antibacterial, anticancer, and antimutagenic properties [7]. Strong hypo-triglyceridemic and serum cholesterol-lowering effects have also been observed [16]. The nutrients in pumpkin are essential for various bodily functions important for good health such as hydration and boosting immune support [26].  Its high-water content and antioxidants make it great for feeling full and boosting your body’s defense. Pumpkin seeds, also called pepitas, are used to reduce prostate enlargement. The high quantity of zinc in the seed can be used for the management of prostate problems. Pumpkin seed oil is mostly composed of linoleic acid, oleic acid, palmitic acid, tacophenol, ß-sitosterol, and delta-7-sterols. Pumpkin pulp is rich in nutrients and health-promoting properties such as proteins, carotene, mineral salts, vitamins, and polysaccharide-like proteins [8]. The significance of this crop in human life makes it crucial to research on and to boost its production to keep up with the rising demand for its products. Soil fertility is a significant issue that hinders the productivity of crops [19]. The optimum temperature range for pumpkin growth and development is paramount to determining yield and quality. Pumpkin plants prefers well-drained, loamy soils with a good balance of sand, silt, and clay and the optimum soil pH range is between 6.0 and 7.5 (slightly acidic to neutral soils). Additionally, environmental factors such as soil moisture, light intensity, and relative humidity, can also influence the plant’s growth and development [14]. Poultry manure is a well-established and desirable organic fertilizer that bolsters soil fertility by adding both essential nutrients and soil organic matter. Each of these components contribute positively to moisture and nutrient retention in the soil [15]. Of all animal-derived manures, chicken manure is considered best organic soil fertilizer  forfor crops due to its richness in most of the major nutrients required for plant growth. Some of these qualities include microbiological activities, soil tilth, and chemical properties [28,29]. The application of poultry manure in record yielded over 53% increases in N level in the soil, from 0.09% to 0.14 % and exchangeable cations increased with manure application [10]. When added in the appropriate amount, poultry manure enhances soil quality and provides nutrients for crop growth because it is high in organic matter and other nutrients required for plant growth [27]. According to [12], adding poultry manure to the soil enhanced its water-soluble qualities and carbon content while decreasing its bulk density. The ideal rates of poultry manure application can vary based on soil nutrient levels, manure source/composition, and specific cultivar needs. Having a soil test done is recommended to determine precise fertilizer requirements when using manures and over application of the poultry manure can lead to nutrient imbalances or salt issues. Poultry manure is considered a high-nitrogen fertilizer, and too much application can lead to excessive vegetative growth at the expense of fruiting. Poultry manure is abundant in nitrogen (3-4% N) and moderate in phosphorus (2-5% P2O5). It is low in potassium, so supplementing with K may be needed, especially for fruiting. The nutrient ratio is around 3-2-1 for N-P-K in poultry manure. It was previously reported that applying poultry manure at rates up to 20 tons/ha significantly improved pumpkin plants’ growth and yield parameters, including vine length, number of leaves, number of branches, leaf length, and stem girth [2]. In a later report, poultry manure application promoted early flowering and … Read more

Potassium Use Efficiency of Modern Rice Variety Influenced by Integrated Nutrient Management Options in Dry Season

  • Chowdhury Md. Humayun Kabir1
  • Alok Kumar Pau2
  • Biswajit Karmakar3
  • Israt Alam4
  • Khalid Syfullah5

INTRODUCTION Rice (Oryza sativa L.) is the primary staple food for more than half of the global population and plays a crucial role in global food security and rural livelihoods [1, 2]. According to Food and Agriculture Organization, rice is cultivated on over 160 million hectares worldwide, producing more than 750 million tons annually [3, 4]. In Bangladesh, rice dominates the agricultural sector, occupying about 75% of total cropped area and contributing substantially to national food supply and farm income [5, 6]. Despite remarkable progress in varietal development and crop management, average rice yield in Bangladesh remains lower than that of major rice-producing countries due to nutrient imbalances, soil fertility decline, and inefficient fertilizer use. Potassium (K) is one of the three primary macronutrients required in large quantities for rice growth and productivity [7, 8, 9, and 10]. It plays key physiological roles in enzyme activation, photosynthesis, osmotic regulation, assimilate transport, and stress tolerance. Adequate potassium supply enhances resistance to lodging, pests, and diseases, improves grain filling, and increases yield stability [9]. Rice crops typically remove 100–300 kg K ha⁻¹ per season, yet K fertilization in many rice-growing areas is often inadequate relative to crop removal, leading to soil K depletion and declining productivity [11, 12]. Continuous intensive cropping, use of high-yielding varieties, and limited recycling of crop residues further aggravate potassium deficiency in South Asian soils. Improving potassium use efficiency (KUE) has therefore become essential for sustainable rice production[13,14,15]. Integrated nutrient management (INM), combining inorganic fertilizers with organic amendments such as cowdung or compost, has been widely recommended to enhance nutrient availability, improve soil physical properties, and increase fertilizer efficiency. Organic amendments can increase cation exchange capacity, reduce nutrient losses, stimulate microbial activity, and enhance K availability from non-exchangeable soil pools. However, information on KUE of modern high-yielding rice varieties under different integrated nutrient management options during the dry (Boro) season remains limited[3]. Modern rice varieties developed by Bangladesh Rice Research Institute have higher yield potential but also greater nutrient demand. Efficient nutrient management strategies are therefore required to achieve high productivity without degrading soil health. Understanding potassium uptake dynamics and use efficiency under different fertilization strategies will help optimize fertilizer recommendations and improve sustainability of rice-based systems [16,17,18]. Therefore, the present study was conducted to evaluate the growth performance, yield, potassium uptake, and potassium use efficiency of a modern rice variety under different fertilizer management options, including recommended practice, soil-test-based fertilization, and integrated nutrient management during the Boro season. The findings are expected to provide guidance for improving potassium management and sustaining rice productivity in intensive rice-growing regions. Materials and Methods Study Site The experiment was conducted during the Boro seasons of 2022 and 2023 at the research field of Sher-e-Bangla Agricultural University, located in Dhaka. The site belongs to the Agro-Ecological Zone (AEZ-28, Madhupur Tract) and is characterised by subtropical monsoon climate with mild winter and hot, humid summer. The experiment was carried out on typical rice-growing silty clay loam soil at the Soil Science Farm of Sher-e-Bangla Agricultural University. Surface soil samples (0–20 cm depth) were collected before land preparation and analysed for physicochemical propertiesThe soil contained 18.60% sand, 45.40% silt, and 36.00% clay, with a pH of 6.8, organic matter 1.38%, total N 0.06%, available P 19.85 mg kg⁻¹, exchangeable K 0.12 meq 100 g⁻¹, and available S 14.40 mg kg⁻¹. Experimental Design and Treatments The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. Plot size was 3 m × 4 m, and plots were separated by 0.5 m bunds. Seven potassium management treatments were evaluated using the rice variety BRRI dhan100: Fertiliser sources included urea for N, triple superphosphate for P, muriate of potash for K, gypsum for S, and zinc sulfate for Zn. Cowdung was well-decomposed before application. Crop Establishment and Management Seeds of BRRI dhan100 were sown in well-prepared wet nursery beds on 11 December 2021 and 7 December 2022. Thirty-five-day-old seedlings were transplanted on 26 January 2022 and 13 January 2023 at 25 cm × 15 cm spacing with 2–3 seedlings per hill. Cowdung was incorporated 20 days before transplanting. The full doses of P, K, S, and Zn were applied during final land preparation, while nitrogen from urea was applied in three equal splits at 15, 30, and 45 days after transplanting. Standard agronomic practices including irrigation, weeding, and plant protection were applied uniformly across treatments. The crop was harvested at physiological maturity when approximately 85–90% of grains turned golden yellow. A central harvest area of 6 m² per plot was used to determine grain and straw yields. Grain yield was adjusted to 14% moisture content and straw yield to 3% moisture. Plant Sampling and Nutrient Analysis Grain and straw samples were oven-dried, ground, and analysed for potassium content. Digested samples were diluted to a known volume, and potassium concentration was determined using a flame photometer. Nutrient uptake was calculated by multiplying nutrient concentration with corresponding biomass yield. Potassium Use Efficiency Indices Potassium use efficiency indices were calculated using standard equations: Partial Factor Productivity of K (PFPK) PFPK (kg kg-1) = GY+K/FK​​ [18] Agronomic Efficiency of K (AEK) AEK (kg kg-1) = (GY+K – GY0K)/FK [18] Recovery Efficiency of K (REK) REK = (UK+K – UK0K)/FK ​​ [18] Physiological Efficiency of K (PEK) PEK (kg kg-1) = (GY+K – GY0K)/(UN+K – UN0K) [18,19] Internal Efficiency of K (IEK) IEK = GY/UK [19] Potassium Harvest Index (KHI)          NHI = GK/TK [18,19,20] where GY+K ​ and GY0K ​ are grain yields with and without potassium, FKis applied potassium, U+Kand U0K ​ are potassium uptake with and without fertiliser, GK is grain potassium uptake, and TK is total plant potassium uptake. Statistical Analysis Data were analysed using analysis of variance (ANOVA) appropriate for RCBD. Treatment means were separated using Least Significant Difference (LSD) at 5% probability level [21]. Statistical analyses were performed using Statistix 10. Experimental Validity The experiment was repeated across two consecutive years to ensure reproducibility and minimise seasonal variability. Uniform crop management … Read more

Farmers’ Characteristics and Constraints in T-aman Rice Cultivation in Bangladesh

  • Md. Jahangir Kabir1
  • Md. Shamsuzzoha2
  • Md. Raju Ahmad3
  • Nur- E -Shahrin Nurani4
  • Madhuri Rani Roy5

2. Introduction Bangladesh’s economy and rural society are strongly shaped by agriculture, which continues to play a pivotal role in employment generation, food supply, and livelihood security. Approximately four-fifths of the population are engaged in agricultural activities either directly or through related sectors, which contributes about 18.4% to the national gross domestic product [1]. Rice (Oryza sativa L.) is the staple food and the dominant crop, occupying approximately 80% of the cultivated land and serving as the primary source of calories for the population [2,3]. However, rapid population growth, declining cultivable land, and increasing climate variability pose serious challenges to sustaining rice production. Rice cultivation in Bangladesh follows three seasonal cycles—Aus, Aman, and Boro—among which transplanted Aman (T-aman) occupies the largest share, accounting for nearly half of the country’s total rice-growing area [4]. Despite its importance, T-aman productivity remains highly vulnerable to climatic stresses, including floods, drought spells, erratic rainfall, cold waves, and riverbank erosion. Such stresses are especially acute in northern Bangladesh, particularly in areas influenced by the Teesta and Jamuna river systems, where fragile agro-ecological conditions and limited opportunities for livelihood diversification restrict agricultural productivity. One of the most critical manifestations of agricultural vulnerability in northern Bangladesh is Monga, a recurring seasonal phenomenon of food insecurity and unemployment. Monga is most pronounced during the pre-harvest scarcity period preceding the Aman rice harvest (mid-September to mid-November) and, to a lesser extent, before the Boro harvest [5]. Poor or unstable Aman rice yields are widely recognized as a major driver of Monga, as rural livelihoods in the region are heavily dependent on agricultural wage labor and a limited number of cropping cycles. In districts such as Gaibandha, Kurigram, Rangpur, Nilphamari, and Lalmonirhat, crop failure or reduced T-aman productivity often leads to sharp income declines, food shortages, and heightened vulnerability among smallholder and landless households. Farmers’ ability to achieve stable T-aman production is constrained by multiple agronomic, environmental, and socio-economic factors. These include drought or untimely rainfall, flooding and waterlogging, lack of early-maturing or stress-tolerant varieties, inadequate access to quality seed, limited extension support, and poor access to inputs [6]. The extent to which farmers confront these problems is not uniform and may vary depending on individual characteristics. Understanding how these characteristics influence farmers’ problem confrontation is essential for designing effective extension strategies and policy interventions aimed at improving T-aman productivity and reducing Monga-related food insecurity [7]. Despite the recognized importance of T-aman rice for food security in northern Bangladesh, systematic empirical evidence on the nature and severity of problems faced by farmers—and how these problems relate to their socio-economic characteristics—remains limited [8]. Most existing studies focus on poverty, food security, or climatic vulnerability, with comparatively little attention given to farmer-level problem confrontation in T-aman cultivation. Addressing this knowledge gap is crucial for developing targeted, context-specific solutions [9]. We did the study to assess the severity of constraints encountered by farmers in cultivation. We selected Monga-affected areas of northern Bangladesh and to examine the relationship between these problems and farmers’ selected personal, economic, and communication characteristics [10]. The findings are expected to provide valuable insights for agricultural extension services, development practitioners, and policymakers seeking to enhance rice productivity and mitigate seasonal food insecurity in vulnerable regions [11]. 3. Materials and Methods Study Area The study was conducted in two villages—Rajabirat and Katabari—located in Gobindaganj Upazila of Gaibandha district, northern Bangladesh. These villages are situated approximately 20 km and 10 km northeast of the district headquarters, respectively. The study sites were selected purposively due to their high dependence on T-aman cultivation and the absence of prior empirical studies addressing farmers’ problem confrontation in T-aman production in this area. Population and Sampling An updated sampling frame comprising 1,029 T-aman farmers was compiled with support from local Sub-Assistant Agricultural Officers. From this population, 10% of farmers (n = 103) were selected. Survey Instrument and Pre-testing Information was gathered out using an interview schedule specifically designed to address the study objectives. The instrument comprised both open- and closed-ended questions and applied appropriate scaling techniques for measuring the selected variables. Before the main survey, the schedule was pilot-tested with ten T-aman farmers from outside the study area, and revisions were subsequently made to enhance clarity, relevance, and overall consistency. Measurement of Variables Farmers’ Characteristics The study examined nine independent variables: age, level of education, family size, experience, area, annual income, knowledge, extension media contact, and innovativeness. Problems Faced by Farmers in T-Aman Rice Production Problem confrontation was measured using 15 statements related to constraints in T-aman cultivation. The severity of each problem was rated by respondents using a four-point scale ranging from high (3) to not at all (0).An overall problem confrontation score was calculated for each farmer by compiling the responses, yielding a possible range of 0–45, with higher values indicating greater severity of problems.To prioritise individual constraints, a (PCI) was calculated. Hypothesis Testing The null hypothesis posited that farmers’ problem confrontation in T-aman cultivation was not significantly associated with their selected socio-economic and communication characteristics. Data Collection Procedure The researcher collected data via direct, face-to-face interviews during October 2012. Interviews were carried out at respondents’ homes or fields during their leisure time. Rapport was established prior to interviews to ensure accurate and reliable responses. Statistical Treatment and Data Analysis The collected data were coded and analyzed using SPSS software (version 11.5). The data were summarized using descriptive statistical measures, including frequencies, percentages, means, and standard deviations. Relationships between farmers’ characteristics and problem confrontation scores were analyzed using Pearson’s Correlation Coefficient (r) at the 5% probability level (p ≤ 0.05). 4. Result 4.1 Socio-economic and Farm Characteristics of the Farmers The linkage between selected farmer attributes and problems facing were analyzed using Pearson’s product-moment correlation coefficients, as presented in Table 4.11. The variables show negative or non-significant relationship. 4.4 Severity Ranking of Problems in T-aman Cultivation The severity of 15 selected problems was assessed using the Problems Confrontation Index (PCI). PCI values ranged from 69.6 to 279.5 (Table 4.12). High cost of production ranked … Read more

Crop Establishment technique in Redgram- A contingency measure forrealizing higher productivity

  • Anitta Fanish S
  • G Guru

Introduction Redgram (Cajanus cajan L. Millsp) is the most vital Kharif pulse crop in India, predominantly cultivated under rainfed conditions. It occupies 3.89 million hectares, contributing 3.02 million tonnes to the national pulse pool; however, its average productivity remains stagnant at 776 kg/ha. The primary barrier to higher yields is low productivity during early growth stages, exacerbated by soil moisture stress and climatic aberrations in the Indian subtropics. During the monsoon, redgram is particularly sensitive to waterlogging, which restricts soil aeration, hinders nutrient uptake, and impairs root nodulation. These unfavorable conditions foster disease incidence and high seedling mortality, leading to a significantly sparse plant stand [1]. Strategically maintaining an optimal plant population in the face of these biotic and abiotic pressures is a major challenge for sustainable production. Furthermore, the late onset of rains often delays sowing, shortening the crop’s vegetative window. To counteract these constraints, transplanting has emerged as a promising alternative. By raising seedlings in a nursery, typically in polyethylene bags and transplanting them into the main field once established, farmers can bypass early-season stressors and ensure a uniform plant stand [2, 3]. Established transplants exhibit rapid early growth and greater competitiveness against weeds compared to direct-sown crops. This technique essentially allows for “virtual” early sowing, enabling the crop to capitalize on the full growing season even when monsoon rains are delayed. However, research regarding optimized nursery protocols, ideal seedling age, and main field configurations is currently limited. Consequently, this study was undertaken to evaluate the feasibility and refine the technical and economic suitability of redgram transplanting for the agro-climatic conditions of Tamil Nadu.   Materials and Methods A two-year field study (2022–2023) was conducted at the main farm of the Department of Agronomy, Tamil Nadu Agricultural University (TNAU), Coimbatore. The experimental site is characterized by a tropical sub-humid climate, featuring an average annual rainfall of 647 mm, with mean annual maximum and minimum temperatures of 33°C and 23°C, respectively. The study was conducted on double-cropped irrigated upland. Prior to the trial, the field followed a Rice–Blackgram rotation. The long-duration redgram variety ‘CO 8’ was utilized for the experiment across both years (2022 and 2023) to assess the efficacy of transplanting as a productivity-sustaining contingency measure. In the field experiments, two transplanting methods (flat-bed vs ridge-furrow) and 4 combinations of nursery raising techniques along with age of seedlings (viz., raising seedling in pro tray or polyethylene bags and transplanting these at 20 and 25 days after seeding; and a control involving in situ seeding in main field simultaneous transplanting with that in portrays and polyethylene bags, were laid out in a factorial RBD with 3 replications. The long-duration variety ‘CO 8’ was selected for its moderate wilt resistance and suitability for the region. Sowing was initiated in mid-July for both experimental years. Prior to sowing, seeds were treated with Rhizobium and Phosphorus Solubilizing Bacteria (PSB) at a rate of 1 kg/ha each to enhance nitrogen fixation and nutrient availability. Transplanting of the long-duration ‘CO 8’ variety was synchronized with the onset of monsoon rains, occurring during the first fortnight of August in both 2022 and 2023. To evaluate the impact of land configuration on seedling establishment, two methods were employed: Flatbed Method, Pits were excavated to a depth of 15–20 cm at 30 cm intervals and Ridge Method, Seedlings were transplanted onto 30 cm high ridges. During transplanting, polyethylene bags were carefully removed to ensure the root zone and surrounding soil ball remained undisturbed, maintaining a uniform spacing of 120 x 30 cm across all treatments. A basal fertilizer dose of 25:50:25:20 kg/ha of NPKS + Zn was applied to all plots. Water management was strictly monitored: Immediate irrigation after transplanting, followed by a life-saving irrigation at 10 days after transplanting (DAT). Supplemental irrigation was provided during the critical branching and pod development stages to mitigate rainfall deficits. The crop reached maturity and was harvested during the first week of March in both 2023 and 2024. Biometric data, including seed yield, yield attributes, and economic indicators, were recorded and subjected to rigorous statistical analysis to interpret the efficacy of the transplanting technology. RESULTS AND DISCUSSION Seedling Age and Survival The experiment highlighted the distinct advantage of utilizing 25-day-old seedlings as a robust crop contingency measure. Raising seedlings in polyethylene bags ensured a high density of healthy, vigorous plants, which effectively buffered against the initial field stresses that often diminish direct-sown populations.   Comparative Performance of Transplanting Methods The crop exhibited significant variation in performance based on both the land configuration and the timing of transplanting. Seedlings transplanted on ridges showed superior root architecture and vegetative growth compared to those in flatbed pits, likely due to enhanced aeration and drainage. Variations in the yield attributes like number of pods per plant and grain weight were directly correlated to the seedling age at the time of field transfer. In respect to economic Viability, While transplanting requires an initial investment in nursery management, the resulting increase in seed yield and plant stand stability significantly improved the overall economics of cultivation compared to conventional methods [4]. The subsequent sections detail the quantitative data recorded over the two-year study period, focusing on the refined schedules that maximize redgram productivity in the Tamil Nadu region. Impact of Land Configuration on Yield and Growth The primary agronomic constraint in redgram productivity is suboptimal plant population, driven by delayed monsoon onset and high seedling mortality from waterlogging. This study demonstrates that land configuration is critical for mitigating these risks. Ridge transplanting achieved a 15.5% (210 kg/ha) yield increase over flat surfaces, regardless of seedling age or nursery method. The yield advantage on ridges is primarily attributed to a 15.6% increase in pods per plant, while 100-seed weight and seeds per plant remained consistent. Ridges provide superior drainage, maintaining soil aeration and nutrient uptake while preventing the negative impacts of waterlogging on nodulation and the rhizosphere micro-environment [8]. Consequently, plants on ridges exhibited more vigorous biometrics, including increased plant height, branch length, and biomass (Table 1), leading to a significantly improved Harvest Index (HI). These findings align with previous research [5, 6, 7] suggesting that raised-bed configurations are essential for redgram sustainability. Optimization of Nursery Technique and Seedling Age Seedling quality and age at transplanting were found to be pivotal for field success. Seedlings raised in black polyethylene bags outperformed those in pro-trays, likely due … Read more

Impact of charcoal on fiber crop, Jute (Corchorus capsularis L) as natural polymer with morphological features, biomass production and root development under natural condition at roof top garden

  • Kamrun Nahar

Introduction: Jute (Corchorus capsularis L- white Jute) is a potential cash crop and natural polymer that belongs to the Mavaceae family, known to Bangladesh as “Golden Fiber” because of earning foreign currency by exporting it. This cash crop strengthens the national GDP and holds economic significance in our country [1], [2], [16], [21]. It is cultivated in an area of about 9,93,000 acres and produces 46,19,000 m. tons in 2005- 2006 [12]. Among the growing countries, Bangladesh ranks in second position in terms of fiber production. In recent years, it has been well focused as considered as natural polymer and a vital sector in the context of economic, commercial, agricultural, industrial, and, more importantly, environmental aspects in Bangladesh as well as the global markets [69],[58], [6], [13]. Thus, the rising demand for jute production is increasing day by day in national and international markets as the products from jute are environmentally friendly and biodegradable. Farmers are also now interested in production and marketing of raw jute because of its economic importance as well as for future potential of global jute market [5] [30], [31], [32],[33],[36], [39], [42], [44], [46] and [55].  As an eco-friendly, annual and major fiber crop, grown well in tropical and subtropical climates, which attains a height of approximately 3-6 meters, with a thickness of about 2- 2.5 cm, and completes its life cycle in 3 months or 90 days. Its 2 important parts, leaves and stalk, could be used in our daily life for consumption and as biomass resources. Besides the potential for fiber, it could be used commercially and exported to foreign countries.  As a sustainable and abiotic stress tolerant and integrated plant biomass, the extraction of fiber could be done in a ecofriendly manner [8],[11],[64], and the extracted fiber from the matured plant used in various types of household products like, bag, carpet, mat, crafts, clothing etc [14], [51]. Besides the fiber, jute sticks are largely used for various domestic purposes as fencing, roofing material, and biomass fuel for cooking purposes, particularly in suburban and rural areas of Bangladesh. In addition, the leaves locally called ‘Pat Shak” are consumed as a vegetable by a major part of our population in urban, suburban and rural areas as well as other Asian countries in the world, which contain different types of vitamins, minerals, protein, including antioxidants [30],[56] and [40]. Furthermore, it contains several metabolites that are important to consider for pharmacological research and human health issues, too [3]. Thus, it is not only considered or used as an economic fiber and cash crop, but it has a tremendous demand as a healthy and nutritious vegetable as well as has medicinal values. The plant has immense adaptability, including sustainability, as it is more water-tolerant and can generally be grown in lowlands and also in waterlogging conditions [68].  Besides, it can be grown in different soil types, ranging from clay to sandy loam with medium to lower fertility status. To evaluate the plant production and maintain the adequate growth, adaptability and yield of Jute production in natural conditions, proper application of amendment is essential to get better biomass yield [7].  In this context, different soil amendments could be used. Jute as an important cash crop that prefers a carbon source. Thus, charcoal could be used as a good amendment and carbon-rich soil conditioner for the production of biomass. It is considered a valuable carbon-rich organic matter that serves as a soil conditioner when applied to soil to improve the fertility status of the soil. It has a synergistic effect that promotes plant growth and development. Besides, its application in soil allows better soil management by increasing microbial activities with the release of essential nutrients required by the plant. Thus, charcoal as a good soil amendment, could be added to soil to increase its fertility, water retention capacity, carbon storage[4],[15],[28] and [29], including improvement of the soil health and fertility status of soil. Jute plants need a number of nutrients for their growth and proper development [66],[70],[71] although applying inorganic fertilizers increases crop yield, but deteriorate soil health as well, resulting in a decrease in crop yield. Charcoal is a carbonized material, which is used to improve soil health and creates a scope to release nutrients slowly as slow releasing amendment. In this present study, charcoal was applied at various rates. Carbonized materials such as charcoal are responsible for the stability of soil carbon, and their application have a ameliorating effect on increasing nutrient holding capacity, including supply in addition of reduction of soil acidity. Thus, maintains soil organic matter in the tropical and subtropical climate due to rapid rates of decomposition. Furthermore, charcoal as a carbonized material and is a cheap source of carbon in soil. However, the varying levels of amendment treatment had diverse effects on seedling and plant growth enhancement [60]. Some of the amendments increased plant height significantly at low levels but decreased with increasing levels of application. However, medium levels of fertilizer as soil amendment promote growth and yield of plants [19]. Charcoal as a carbon source as well as organic fertilizer, is important as it promotes the growth and development of the jute plant. Therefore, an experiment was conducted to investigate the influence of different levels of charcoal as carbon rich amendment on the growth and development of Corchorus capsularis. Materials and Methods: A pot experiment was carried out to study the response of jute (Corchorus capsularis) with the variety, BJRI Deshi pat -10, at the rooftop of 3 storied building in Dhaka, Bangladesh. The experiment was conducted to evaluate the impact of various rates of carbon source, such as charcoal, a potential soil amendment, on morphological features, biomass production, and root development of the mentioned Jute plant as a natural polymer or fiber crop. In the experiment, 6 treatments of charcoal were applied at the rate of control, 1g, 2g, 3g, 4g, and 5g as the treatments, T0, T1, T2, T3, T4, and T5, respectively for a period of 5 weeks.  … Read more

Genotypic Variation and Seed Morphological Determinants of Maize (Zea mays L.) Performance and Resistance to Bacterial Streak in a Naturally Infected Field

  • Bukola Ojo Adediran1
  • Oluwafemi Michael Adedire2
  • Olufemi Stephen Olaoye3

Introduction Maize (Zea mays L.) is one of the world’s most important cereal crops, serving as a primary source of food, feed, and industrial raw material. Maize (Zea mays) cultivation and exploration have been at their all-time high in Nigeria and indeed, all parts of the globe [2]. In many maize-growing regions, particularly in tropical and subtropical environments, productivity is constrained by a wide range of biotic stresses, among which bacterial diseases have gained increasing importance [19]. One of the emerging bacterial diseases affecting maize is Bacterial Leaf Streak (BLS), caused by Xanthomonas vasicola pv. vasculorum (Xvv) [14]. The disease is characterized by elongated, water-soaked lesions on leaves that coalesce to form streaks, leading to reduced photosynthetic area, premature senescence, and ultimately yield losses. In endemic areas, especially where climatic conditions favor disease development, bacterial streak has become a major challenge to sustainable maize production [20]. Chemical and cultural management strategies for bacterial streak are largely ineffective or uneconomical due to the limited availability of effective bactericides and the polycyclic nature of the pathogen [12]. Consequently, host-plant resistance remains the most viable and environmentally friendly approach for disease management [7]. However, the genetic basis of tolerance to bacterial streak in maize is complex, and resistance levels among available germplasm are variable [13]. Identifying and selecting genotypes that combine superior agronomic performance with tolerance to bacterial streak is therefore critical for breeding programs targeting disease-prone environments. Field evaluation of maize genotypes under natural disease pressure provides an opportunity to assess both yield performance and resistance stability under realistic agronomic conditions [9]. Such assessments help distinguish genotypes that can maintain acceptable productivity despite infection pressure, making them valuable candidates for further breeding and deployment in endemic regions [6]. Furthermore, understanding the interaction between the performance of released maize genotypes from research institutes like the Institute of Agricultural Research and Training (IAR&T) and disease intensity contributes to the development of selection indices that integrate yield potential, seed morphology, and disease tolerance [8]. The present study was therefore undertaken to evaluate the agronomic performance of eight (8) maize genotypes released by IAR&T, Ibadan, in a bacterial streak endemic field in order to identify promising genotypes and grain size that combine high yield potential with stable tolerance. Materials and Methods The experiment was conducted at the Teaching and Research Farm of Cocoa Research Institute of Nigeria (CRIN), Ibadan, Oyo State. Seeds of eight genotypes of maize used for the experiment were obtained at the seed store of IAR&T, Ibadan, Oyo State (Table 1). The experiment was carried out during the early cropping season of 2023 (May – August) on a bacterial streak endemic field [3]. Maize seeds (500 g) of each cultivar were sorted into three different sizes (big, medium, and small) [24][17]. One hundred seeds were randomly selected from each category to determine seed morphometrics through the use of a digital variety caliper (Table 2). The experiment was laid out in a randomized complete block design (RCBD), replicated three times. The experimental field was laid out in three blocks, and each block comprised three replicates. Inter-block spacing was 2.0 m, inter-row spacing was 0.75 m while intra-row spacing was 0.50 m and seeds were sown at 2 cm depth. Data were collected on five randomly selected plants to study the agronomic traits: Plant height at 95% maturity (cm), leaf area (cm2), stem girth (cm), cob length (cm), cob girth (cm), total grain weight (kg), cob weight/fruit (kg), grain yield per hectare (kg), harvest index (calculated as percentage of grain weight divided by total biomass), shelling percentage was calculated as percentage of grain weight divided by cob weight (%), 1000-seed was the average weight of 1000 seeds obtained from five shelled cobs (kg). The data collected were subjected to analysis of variance (ANOVA) using statistical analysis software [22]. Means were separated using Duncan’s multiple range test (DMRT) at 5% probability. Isolation of Xanthomonas vasicola and characterization of bacterial streak Affected portions (5 mm sections) of infected leaves were inoculated on Nutrient Agar for isolation of the streak pathogen (X. vasicola). Samples were surface-sterilised with 2% sodium hypochlorite, rinsed thrice with sterile water, drained, and inoculated on prepared agar plates [2]. Microbial strains were isolated from infected tissue samples on Nutrient Agar, and bacterial streak disease was eventually characterized in the maize genotypes as reported by Malvick et al., 2024 [15]. A modified disease severity scale (0-5) for maize streak was used Mushayi et al., 2025 [16], while percentage incidence [18] of the disease was determined as described below: Resistance and tolerance to bacterial wilt were determined according to the rating class described by Borisade et al., 2017 [5] as < 1% and ≤ 25% severity measures, respectively. Results and Discussion Performance of maize genotypes The mean performance of growth characters evaluated in the eight varieties of maize is presented in Table 3. There was no significant difference among the varieties in terms of their stem girth and seed sizes, although variety ART-98-SWI (Small) recorded the highest mean of 6.26 cm. There was no significant difference in the plant height of maize; however, plant height for small seed size was lower, considering seed size. This was in concordance with the result observed in a collection of soybean varieties [27]. Mean performance of yield and yield components evaluated in the eight (8) varieties of maize is presented in Table 4. With reference to cob length, there was no significant difference in the varieties and seed sizes. However, variety Suwan-1 (Large) recorded the longest cob length (28.20 cm) while ALT-98-SW6 (Small) recorded the least cob length (23.49 cm). For cob girth, there were significant differences among the varieties; variety ALT-98-SW6 (Large) recorded the widest average cob (17.83 cm), while the shortest cob girth was recorded for variety LNTP (Small). For 1000-seed weight, a significant difference was observed among the varieties and their seed sizes. Variety DMR-LSR-Y (Small) recorded the heaviest weight (0.38 kg). Variety LNTP (Medium) recorded the heaviest/largest total grain yield (0.23 kg). PRO-VIT-A (Medium) recorded … Read more

Potential of Large Non-coding RNA (lncRNA) in Plants and Human Specially Neurogenerative and Cancer

  • Satyesh Chandra Roy

Introduction                                                                        With the discovery of the structure of DNA by Watson and Crick in 1953, there comes the discovery of the Central Dogma which states that genetic information stored in DNA is transcribed to messenger RNA (mRNA),  followed by the formation of protein. . Further research has found the discovery of non-coding RNAs in the period 1950 to 1980s, the non-coding tRNA and rRNA in 1960 , followed by early regulatory non-coding RNA(ncRNA) in 1980 . The publication of Human Genomes in 2001, high – throughput sequencing and the ENCODE project have significantly boosted this research, leading to the characterisation of many ncRNAS. In this way, several ncRNAs have been known, such as micro RNAs (miRNAs), small interfering RNAs (siRNAs), small nuclear RNAs (sn RNAs), small nucleolar RNAs (snoRNAs), small Cajal body-specific RNA (scaRNA), piwi-interacting interacting RNA (piRNA) and Long non-coding RNAs (incRNAs).  This scaRNA is a class of small non-coding RNA located in the Cajal body (membrane-less nuclear organelles found in eukaryotic cells ), crucial for small nuclear riboprotein (snRNP) biogenesis. Their functions  are to guide the modification of of spliceosomal RNAs (U1, U2, U4, U5 and U12) for the proper functioning of the spliceosome during RNA processing.  The piwi- interacting RNAs are small non-coding RNAs of generally 25-33 nucleotides long found in animal cells to form RNA-protein complexes with PIWI- like proteins to silence transposable elements from moving within the genome. PIWI proteins are a family of Argonaute proteins that interact with pi RNA to regulate gene expression.  Different types of non-coding RNAs found in different organisms have a great potential in understanding the complexity of the organism and the regulatory functions of these RNAs in many cellular processes, particularly in gene regulation. With the advancement of transcriptome analysis in mammals large number of long transcripts have been know which have no protein-coding capacity and so it is called Long or Large non-coding RNAs (lncRNAs), the potential of which will be discussed below.  Large/Long Non-coding RNA (lncRNA) and its Function  With the advancement of  transcriptome analysis in many organisms, it has been noted that the genomes of mammals and other organisms have produced thousands of long transcripts without any protein-coding capacity . These are called long non-coding RNAs (lncRNAs). It has been noted that about 70% of the mammalian genome is actively transcribed, but only 1-2% of it are protein –coding genes [1].  Large non-coding RNAs (lncRNAs) are generally of more than 200 nucleotides long without any protein-coding capacity but it has been noted that they have functions in gene regulation and disease development. With respect to protein-coding genes , lncRNAs can be intergenic, can be intergenic, antisense or intronic. They are also derived from pseudogenes. About 10,000 pseudogenes were found in the mouse and about 15,000 were identified in the human genome [2, 3].  Pseudogenes are non-functional copies of genes that have lost their protein-coding capacity due to mutations during evolution. They are derived from functional genes and are located near their parent genes. Pseudogenes have similarities with functional genes and they can produce non-coding RNAs on occasion . The mammalian pseudogene Lethe is known as large  non- coding  RNA (LncRNA) that plays a role in regulating the inflammatory stimuli and can be used as anti-inflammatory therapeutic suggesting the regulatory functions within the genome. But not all pseudogenes are functional but some have regulatory functions. The pseudogene Lethe can inhibit the ability of RelA protein (p65) , encoded from RELA gene, by binding to NF-kB promoters leading to RelA deficiency  which can cause chronic muco-cutaneous lesions and susceptibility to TNF-induced apoptosis.  lncRNAs can originate from various genomic processes like duplication of protein-coding genes , existing non-coding genes and through retrotransposition, tandem duplications and the insertion of transposable elements.  lncRNAs may also originate from nuclear RNA polymerases through transcription and post transcriptional modifications . Five RNA polymerases , such as POL I, POL II, POL III and plant specific POL IV and POL V are transcribing diverse types of lncRNAs involving RNA-directed methylation as well as regulating transposable elements in plants [4].  On the basis of genomic localisation , lncRNAs are classified into three types    such as i) Long intergenic non-coding RNAs  without any overlapping with other gene ; ii)   Intronic Large non-coding RNAs which is localised within the intron of a gene ; and iii) antisense lncRNA which is transcribed from the opposite DNA strand of the protein coding gene.  Again some of the lncRNAs of mammals are derived from RNA polymerase II, for this reason those lncRNAs are similar to mRNA (1). There is another functional lncRNA known as XIst that helps in the inactivationof one of the X chromosomes of mammals. Dr. Maite Huarte, a molecular biologist at the University of Navarra in Pamplona, Spain, established the functional importance of lncRNA in cellular pathways and the regulatory functions in gene expression and also in different diseases of human, including cancer.  It has been known that Transposable  elements (TE) is responsible for providing new transcripts but they have another function of bringing functional elements into lncRNA. During the study of Genomic evolution, it has been noted that 45% to 65%  of the genome originated from the parasite genome through the insertion of transposable elements. It has been observed that most of the lncRNAs contain at least one TE and human Endogenous Retrovirus (ERV) . The function of Xist ( X chromosome inactivation) and dosage compensation in mammals, is due to the presence of lncRNA. The sequence study of the Xist region showed that there are several repeat domains, like i) Rep-A originated through insertion of ERVB5; ii)  Rep-C and Rep-F from ERVB  4 ; and iii) insertion of transposon. Another interesting finding is that the the number of lncRNA has increased during animal evolution, leading to the idea that there is a role of lncRNA in forming complexity in higher organisms [1]. Function of lncRNA   Large ncRNAs have a diverse function in cellular processes like cell proliferation, differentiation, stress responses and apoptosis. … Read more

Influence of Arbuscular Mycorrhizal Fungi on performance of Amarathus viridis cultivated in water-stressed Soil

  • Henry Anozie
  • Ogechi Ukoha
  • Victor Okereke

Introduction Traditional leafy vegetables (TLVs), like Amaranthus, have been vital to rural household food systems in Africa for generations, particularly among low-income populations in tropical regions such as Nigeria [19]. The importance of Amaranthus as a vegetable cannot be overstated. Its leaves and tender shoots are commonly boiled and prepared with modern culinary ingredients and they may also be dried during the dry season for use. Amaranthus is one of the few dicotyledonous plants that exhibit C₄ photosynthetic metabolism, a highly efficient photosynthetic pathway that confers high productivity. This characteristic makes Amaranthus a valuable vegetable crop for enhancing food and nutrition in developing African countries [12]. Water scarcity threatens not only arid and semi-arid regions but also other agricultural productive areas that depend on adequate water availability for successful horticulture. Ongoing climate change is expected to intensify both the frequency and severity of drought events worldwide [17], possibly undermining agricultural success achieved to date. Drought represents one of the most severe abiotic stresses, causing greater reductions in crop productivity than most other stress factors [11]. Limited water availability induces stomatal closure, which restricts CO₂ uptake and later reduces photosynthetic activity and carbon allocation [15]. In addition, water stress adversely affects nutrient availability, particularly phosphorus. Severe drought conditions adversely impact plant physiology, growth, development, and reproduction, leading to substantial yield losses and reduced crop quality. Thus, there is an urgent need to develop strategies that could enhance agricultural resilience and mitigate the adverse effects of water scarcity on crop productivity. Such strategies include increased attention to beneficial soil microorganisms, particularly arbuscular mycorrhizal (AM) fungi. Arbuscular mycorrhizal fungi are ubiquitous soil microorganisms capable of forming symbiotic associations with the majority of terrestrial plants. These fungi provide numerous benefits to their host plants [4]. Beyond improving plant nutritional status, AM fungi enhance plant performance and tolerance to various environmental stresses, especially drought stress. The utilization of AM fungi is considered one of the most effective approaches for increasing plant tolerance to environmental stressors [3]. Previous studies have demonstrated that AM symbiosis significantly enhances plant tolerance to water deficit through improved water and nutrient uptake, modifications in host physiology such as photosynthesis and osmotic adjustment, regulation of phytohormones, and the activation of more efficient antioxidant defense systems [7]. Regrettably, there is still dearth of information on the comparative effect of mycorrhiza inocula on the performance of Amaranthus under varying water-stressed environments. Hence, this study is a necessity. Therefore, the objectives of this study were to: Materials and Methods Study area The experiment was conducted at the Screen house of the Department of Crop and Soil Science, University of Port Harcourt at latitude 4054 N and longitude06055 E with an average temperature of 27 0 C, relatively humidity of 78 % but decreases slightly in dry season and an average rainfall ranging from 2500 – 4000mm per annum [2]. The area has a bimodal rainfall pattern with a long rainy season usually between March and July and a short rainy season from September to early November after a short dry spell in August and a longer period from December to February [1]. Soil Sampling and data collection Samples of soil (0 to 30 cm depth) were taken randomly from the research and teaching farm for sterilization. The soil collected was sterilized at a temperature of 121 oC for 4 hours. Data on plant growth parameters collected at 1-week interval were plant height (cm). Number of leaves. Leaf area (cm) and stem girth (cm). Source of Amaranthus spp The Amaranthus spp used for the experiment was gotten from Rivers State Agricultural Development Programme (ADP), Port Harcourt. Arbuscular mycorrhiza fungi and source The source of the mycorrhiza is from the Department of Microbiology, University of Ibadan. AMF inoculum: pure strains of 3 species of AMF were used for the experiment, namely Glomus. clarium, Gigaspora. gigantea and Glomus. mossea. Design and Treatments The experiment consisted of two factors: three species of mycorrhiza and five irrigation levels, arranged in a Completely Randomized Design (CRD). Amaranth seeds were sown in cell trays and allowed to germinate, after which the seedlings were maintained in the trays for six weeks. Prior to transplanting, pure strains of arbuscular mycorrhizal fungi (AMF) were inoculated into the experimental pots at a rate of 20 g per pot. One amaranth seedling was transplanted into each plastic pot with an internal bottom diameter of 30 cm, an internal top diameter of 30 cm, and a height of 35 cm. The five irrigation treatments consisted of 20% field capacity (0.20 FC), 40% field capacity (0.40 FC), 60% field capacity (0.60 FC), 80% field capacity (0.80 FC), and 100% field capacity (1.00 FC). Irrigation levels were monitored using tensiometers (Irrometer Co., Riverside, California, USA) by measuring soil water potential. One tensiometer was installed in a representative pot for each treatment at a soil depth of 10 cm to guide irrigation scheduling. Irrigation was applied whenever soil water potential reached −20 kPa (centibars), with watering carried out at three-day intervals. Field capacity was determined using the gravimetric method. At field capacity, the volume of water required per pot was 27 cl. Accordingly, irrigation treatments of 0.20 FC, 0.40 FC, 0.60 FC, 0.80 FC, and 1.00 FC corresponded to 5.4 cl, 11 cl, 16 cl, 22 cl, and 27 cl of water per pot, respectively. Agronomics practices Cultural practices were observed throughout the period of the experiment. Weeding was done manually using the handpicking method. Watering was done once at an interval of 3 days in the morning or evening. Collection of Data The following data were collected, number of leaves, plant height, stem girth and leaf area. The first data collections were done two weeks after transplanting (WAT). Thereafter, data were collected at an interval of one week. Laboratory analysis  Particles size distribution was done using the hydrometer method as described by [5]. Soil pH was determined in 1:1 (soil: water) ratio using a glass electrode pH meter. Organic carbon was determined by the wet oxidation method [20]. Total … Read more