Original Research Article

First finding of Heritiera littoralis and its significance for Mauritian mangrove conservation

  • Naohiro Matsui1
  • Nabiihah Bibi Roomaldawo2
  • Satoshi Sasakura3

Introduction Importance of mangroves in Small Island Developing States (SIDS) In Small Island Developing States (SIDS) like Mauritius, mangroves are particularly important for strengthening their resilience to climate change, providing important habitats for marine life as fishery resources, and food security and livelihoods for coastal communities [1]. Mangroves act as a natural barrier against natural disasters, especially storms and floods and have the capacity to prevent more than US$65 billion in damage annually by reducing coastal flood risk in areas inhabited by an estimated 15 million people [2]. In SIDS, mangroves function as natural barriers against storms, erosion, and flooding, and have the capacity to prevent more than US$65 billion in damage annually by reducing coastal flood risk in areas inhabited by an estimated 15 million people [3]. Mangroves capture sediments and pollutants that can run off into the ocean, while seagrass beds provide an additional barrier to prevent mud and silt from covering coral reefs. Coral reefs, on the other hand, protect seagrass beds and mangroves from strong waves. Therefore, the collapse of any of its components can lead to the collapse of the entire system, meaning that an integrated coastal ecosystem management (ICEM) approach is essential to ensure the overall health and resilience of island coastal areas [4]. Status of mangrove ecosystems in Mauritius and conservation issues Mauritius was previously thought to be home to only two species of mangrove plants [5-7], with Rhizophora mucronata (RM) being the most dominant, and Bruguiera gymnorhiza (BG). Bunting et al. (2022), using a global satellite dataset called Global Mangrove Watch (GMW), reported the mangrove area in Mauritius to be about 4.32 km² [9]. Mangroves are distributed along the northeast, east, and southeast coasts, with smaller patches in southwestern regions. The mangrove forests in the southeastern region, where this study was conducted, are the most developed and mature, as evidenced by their tall tree heights and large tree sizes. The factors that determine mangrove expansion and productivity vary depending on the type of mangrove forest (delta, marine, estuarine, lagoonal), so it is important to understand the environmental factors specific to each type [10, 11]. In each type, mangrove area is not determined by a single factor, but by a complex interplay of multiple factors such as hydrology (tides, waves, current velocity), freshwater and nutrient supply, sediment supply and stability, salinity, and human activities. Mangroves in Mauritius are predominantly estuary and lagoon type [6]. Salinity gradients and human activities are thought to have distinctive effects on mangrove forests in estuarine types, while wave activity and water quality in the lagoons are distinctive factors affecting mangrove forests in lagoonal types. JICA Project for the Development of an Integrated Coastal Ecosystem Management System in the Republic of Mauritius Since 1995, the Government of Japan, through the Japan International Cooperation Agency (JICA), has made long-term contributions to the conservation and restoration of Mauritius’ coastal ecosystems, as well as the preservation of coastal fisheries resources and the environment. In 2022, JICA, in cooperation with the Government of Mauritius, launched the technical cooperation project titled “The Project for the Development of Integrated Coastal Ecosystem Management System.” The overall goal of this project is to promote the conservation and restoration of coastal ecosystems through integrated coastal ecosystem management systems, aiming for healthier and more resilient states. This research was conducted as a component of this initiative.   Aims of this study Although the ecological and socio-economic importance of mangroves is recognized, scientific research on mangroves in Mauritius is still limited. In Mauritius, only two mangrove species have been identified, RM and BG [6]. While this recognition has been going on for a long time, this study confirmed for the first time that Heritiera littoralis (HL) is present in Rivière des Creoles (hereinafter called RC). The goal of this study is to scientifically document its presence, understand the growing conditions in which HL thrives, and provide a basis for ensuring its long-term health and sustainability of the mangrove ecosystem in RC and other coastal areas of Mauritius. Materials and methods Site description and mangrove survey The same estuary-type mangrove as that found at RC (where HL was found) is also present 2 km north at Rivière Nyon (RN) (Fig. 1). They belong to different estuarine systems regarding freshwater inputs from different rivers, different catchment characteristics, and different estuary shapes and openings to the sea. 3 plots (C1, C2, C3) and 3 plots (N1, N2, N3) with the size of 20 x 25m were set up at RC and RN, respectively. All stems were tagged with numbering tape. 555 trees at 6 plots in RC and RN were measured for height and diameter at breast height (DBH), and from which basal area and stand density were calculated. The position of measured trees also was also determined. RM sometimes has plural stems in one single tree. In that case, the ground level measurement was done at 30 cm above the prop roots. Tree heights were subsequently measured with a measuring pole and/or by visual observation. Ground level survey Topography, or ground elevation, determines the dynamics of water flow and nutrient inputs within mangrove forests. It is considered the most important factor for mangrove growth [12, 13] and is recognized as crucial for the distribution of mangrove species [14]. Topography is closely related to soil properties, and in turn soil properties are closely related to plant growth. Therefore, mangrove growth can be better explained when soil properties are taken into consideration with topography [15]. Ground level measurements were taken at 5-meter intervals from the coast inland through the mangrove forests in both the RC and RN plots. These measurements were performed using an Ushikata pocket compass (Model S-25, Ushikata Surveying Instruments Co., Ltd., Japan). Soil analysis For the assessment of soil moisture and bulk density, undisturbed soil samples were obtained using 100 cm³ stainless steel sampling tubes (Daiki Rika Kogyo Co., Ltd., Japan) at different depths with 5 cm intervals till 30 or 35cm. The pH and electrical conductivity (EC) of the fresh soil samples were measured after … Read more

Occurrence, detection and transmission of Pseudomonas syringae pv. lachrymans from the seeds of Cucumber (Cucumis sativus L.) in Rajasthan

  • Poonam Arora1
  • Dilip Kumar Sharma2

I. Introduction The cucumber (Cucumis sativus L.), a member of the Cucurbitaceae family, is a primitive vegetable that originated in India and is consumed as a cooked or salad produce. 1. It is a wide-ranging and heterogeneous family that comprises worldwide 118 genera and 825 species2, 3 and 36 genera and 100 species in India4. It is widely known as Kheera and Gherkins in the tropics, subtropics and temperate zones of India5. In India cucumber are grown as a vegetable that is used for domestic purpose and exported to other countries for foreign income. Bharatpur, Jaipur, Bikaner, Dausa, Hanumangarh, Pali, Sawai Madhopur, Sikar, Sirohi, Karauli and Dholpur are major cucumber-producing districts in Rajasthan. The disease angular spot (ALS) in cucumber was first discovered in the United States in 1913 and the pathogenic organism was identified in 1915 by Smith and Bryan. In Japan, it was first reported in 1957. In Turkey, it may cause considerable yield losses in both greenhouses and field agriculture 6,7. The crop is invaded by several fungi, bacteria, viral diseases which reduced the quantitative and quality values of the crop. ALS is caused by Pseudomonas syringae pv. lachrymans (Smith & Bryan) Young, Dye & Wilkie. The complex species Pseudomonas syringae divided into 64 pathovars on the basis of pathogenic characters, and Pseudomonas syringae pv. lachrymans (PSL) is one of them8-14. Following the pathogen’s attack, the cucumber leaves developed vein-limited, water-soaked lesions with or without a chlorotic halo. Water-soaked spots on fruits that could be deformed 15-16. Angular leaf spot (ALS) is limiting its open-field production17-18. It could result in large yield reductions in both field and greenhouse crops7. Cucumber and other cucurbit producers in Turkey suffered significant harm and financial loss as a result of the disease’s proliferation-promoting climate19, 20. It caused water-soaked blisters on the leaves, which eventually turned necrotic and decreased the leaf’s ability to photosynthesize21, 22. Depending on the species’ susceptibility, ALS can cause yield losses of up to 30%–60% in fruits by reducing the ability to photosynthesis of diseased leaves 16. Once attacked by PSL on the cucumbers the yields decrease significantly, caused by reduced photosynthetic capacity of the infected foliage, and the disease is difficult to control22. In China, during 2014-2016, the disease incidence varied from 15 to 50% in different fields, causing 30–50% of yield losses14. The disease is responsible for economic losses in cucumber production worldwide9, 21. With 2.1 million hectares and 71.3 million tons produced in China, the USA, and the EU, uninfected cucumber farming is extremely important 23. The bacterium is Gram negative and KOH solubility test negative but levan and catalase are positive. It is oxidase, potato rot; nitrate reduction and arginine dihydrolase negative. The bacterium is non-fluorescent, non-hydrolyzing of starch and gelatin24. The goal of this research was to examine the transmission and detection of the disease, and this study was carried out because PSL needs appropriate detection techniques to enhance effective management strategies. Pathogen isolation and biochemical identification are the primary detection methods, although molecular approaches like rep-PCR and PMA-qPCR have been reported to be employed for PSL detection 25-27. In addition to offering quick and sensitive detection, loop-mediated isothermal amplification assays (LAMP) 28-31have been widely used for plant pathogen detection because they can be used outside of traditional laboratory settings and offer a variety of detection strategies 32. II. Materials and Methods (I) Incidence of pathogen All 102 seeds, 50 fruits samples and various infected plant parts of cucumber collected from storage houses, market and farmers field of 16 districts of Rajasthan, were brought to the laboratory to know the disease sign on various parts of plant. In order to isolate the pathogen, the seed samples and other plant components were surface sterilized and incubated under aseptic conditions on moistened blotter papers in the context of Petri plates and Nutrient Agar media. To isolate the pathogen, all of the cucumber seed samples underwent dry seed examination (DSE) and were incubated on a moistened blotter in SBM 33. The pure form of bacterial colonies were incubated at 30o C for 48 hrs, and were used for various biochemical tests viz. Gram’s staining, KOH solubility test, and LOPAT24, 34-35, and pathogenicity test24  to identify of the species of bacteria. The host plant and other plant species were used to investigate the pathogenicity of the pure bacterial isolates that were found using different techniques. The diseased fruit and other plant parts are subjected to incubate on NA media and moistened blotter papers to know the characterization of the bacterial colony i.e. shape, size, elevation, color, pigmentation, margin, and growth pattern.  (ii) Disease transmission For transmission tests, two naturally infected cucumber seed samples (Lab. ac. no. CU-1412 and CU-1420) with 78 and 82% infection on the standard blotter method (SBM) and 94–100% on Kings medium B were chosen. The 100 seeds per category per sample were sowed on moist blotters (10 seeds/plate) and 1% water agar medium in test tubes (1 seed per test tube, TTSST). The seeds were then incubated at 25±2o C for 12/12 h cycles of light and darkness up to 7 and 14 days, respectively. In the pot experiment, 100 seeds per category per sample were planted in pots (two seeds per pot), and information on symptoms, seed germination percentage, and death was noted. At various phases of plant growth, the pathogen was separated from the affected portion of the plant.  (iii) Pathogenicity test                                                                                                            The bacterial isolates were artificially inoculated utilizing methods like smothering of seeds, stab inoculation of seedlings at the 3-4 leaf stage of the crop, and other plant parts. The host and other plants, such as round, bitter, bottles, and sponge gourds, were used to test the pathogenicity. Cucumber seeds that were susceptible to PSL were planted in plastic pots with sterilized soil and kept in a standard development chamber at 250°C during the day and 220°C at night. Sodium lamps were used to illuminate the pots for 16 hours17. The bacterial inoculums yielded for 24 hrs on Kings medium B (agar medium) at 280C … Read more

Influence of Light Intensity and Growing Media on the Growth and Yield of Solanecio biafrae

  • Kehinde-Fadare A. F.
  • Olajide Olubunmi
  • Arowosegbe Temitope

Introduction  Solanecio biafrae (family Asteraceae) [1] is an underutilized indigenous leafy vegetable widely consumed in parts of West and Central Africa. In southwestern Nigeria, it is locally known as worowo, while in Sierra Leone, it is referred to as bologi. The plant is predominantly found under the shade of tree crops and is commonly cultivated beneath cocoa and oil palm plantations, where the humid, well-drained, and fertile soils favour its growth [ 2] Despite its nutritional and economic potential, cultivation of S. biafrae remains limited to small-scale production in Nigeria, Uganda, and Cameroon [2]. Its production is further constrained by environmental and agronomic challenges, leading to irregular production and threatening its availability [ 3]. The domestication and large-scale cultivation of S. biafrae is therefore crucial to ensure consistent production and to promote its utilization as a sustainable food resource. Among the factors that determine its growth performance are light intensity and growing medium. Light serves as the primary energy source for photosynthesis and is a major driver of plant growth and development. [4]. Suboptimal light conditions can limit crop performance, whereas adequate light promotes photosynthetic activity and vegetative growth. Previous research has shown that low to moderate light intensity can enhance leaf production in S. biafrae [5]. In addition to light, the choice of growing medium influences nutrient availability, root development, and overall yield, making it a key determinant of successful vegetable production. Despite these perceptions, limited research has investigated the combined effects of light intensity and growing media on the performance of S. biafrae. This study was therefore conducted to examine the influence of varying light intensities and growing media on the growth and yield of S. biafrae, with the aim of identifying optimal production conditions for sustainable cultivation. Objectives The primary objective of this study was to evaluate the effects of different light intensities and growing media on the growth and yield of Solanecio biafrae. Specifically, the study was aimed at: 1. Assessing the individual effects of light intensity and growing media on leaf number, plant height, and fresh weight. 2. Examining the interaction between light intensity and growing media on growth and yield performance Materials and Methods Experimental Site The study was conducted at the teaching and research farm of the Faculty of Agricultural Sciences, Ekiti State University (EKSU), Ado Ekiti, located in the southwestern region of Nigeria characterized by a humid tropical climate rainforest zone. The area experiences a bimodal rainfall pattern, with an annual average rainfall of 1,200–1,500 mm and temperatures ranging between 25°C and 30°C. The experimental period lasted for two months. Planting Material Healthy stem cuttings of Solanecio biafrae were collected from established local farms in the vicinity and were sterilized in a solution of food-grade hydrogen peroxide before planting. Experimental Design The experiment was laid out in a factorial arrangement (3 × 4) in a completely randomized design (CRD), with three replications. The factors were: Light intensity: half shade (HS; 600 flux), more intense shade (MIS; 63.6 flux), and full light (FL; 1120 flux). Growing media: rice husk + cocopeat (M1), rice husk alone (M2), biochar (M3), and topsoil (M4). Treatments and Management Shade intensities were achieved using different tree stands of diverse shades and an open field, while flux values were measured using a light meter. Growing media were prepared in equal proportions by volume. Plants were transplanted into growing bags each containing 5 kg of medium Data Collection Growth and yield parameters were recorded at 8 weeks after planting (2 months). Measurements included: Number of leaves: Plant height (cm): measured from the soil level to the apical bud. Fresh weight (g): determined by harvesting and weighing shoots immediately after collection. Statistical Analysis Data collected were subjected to analysis of variance (ANOVA) using IRRI STARS software version 2.0.1. RESULTS Effect of Light Intensity on Growth and Yield of Solanecio biafrae Light intensity significantly influenced plant growth and yield (Table 1). Plants under half shade (HS; 600 flux) produced the highest number of leaves (23.38), followed by more intense shade (MIS; 63.6 flux; 21.62), while full light (FL; 1120 flux) recorded the lowest (20.88). Plant height was greatest under MIS (35.31 cm), intermediate under HS (24.44 cm), and lowest under FL (20.69 cm). Fresh weight was similar under FL (20.77 g) and HS (20.10 g), but significantly lower under MIS (13.99 g). Effect of Growing Media on Growth and Yield Growing media also had a marked effect on plant performance (Table 1). Biochar (M3) and rice husk + cocopeat (M1) supported the highest leaf numbers (26.33 and 25.25, respectively), plant heights (32.00 and 31.33 cm), and fresh weights (21.27 g and 22.39 g). In contrast, rice husk alone (M2) and topsoil (M4) resulted in significantly fewer leaves (17.92 and 18.33), shorter plants (22.42 and 21.00 cm), and lower biomass (15.49 g and 14.00 g). Interaction of Light Intensity and Growing Media Significant interactions were observed between light intensity and media (Table 2). Under HS, biochar (HS × M3) produced the highest leaf number (31.00) and plant height (62.75 cm), while HS × M1 gave the greatest biomass (24.90 g). Under MIS, rice husk + cocopeat (MIS × M1) supported the highest leaf. Discussion The findings highlight the role of light intensity in determining the performance of S. biafrae. Moderate shading (HS) enhanced leaf production compared to FL and MIS, backing up earlier work by [ 5]. The improved performance under HS likely reflects reduced photo-inhibition and increased leaf expansion efficiency. Plant height was greatest under MIS, a typical shade-avoidance response where limited light availability induces stem elongation to maximize light capture [ 6]; however, this elongation did not translate into greater biomass, as excessive shading compromised assimilate production. Growing media also strongly influenced growth and yield. Biochar and rice husk + cocopeat consistently supported more vegetative growth, likely due to improved nutrient retention, aeration, and water-holding capacity. Similar benefits of organic substrates for vegetable production have been widely reported [7]. In contrast, rice husk alone and topsoil yielded poor growth, likely … Read more

Microbiome of centenary trees growing around historical monuments

  • S. F. Abdulloeva1
  • S. S. Fayzullayev1
  • B. I. Turaeva2

Introduction Trees are one of the main components of the Earth’s biosphere and play an essential role in maintaining ecosystem structure, stability, and biodiversity [1]. They provide important ecosystem services such as nutrient retention and water filtration [2]. In parks, recreational areas, and historical sites, trees are valued for their health benefits and aesthetic importance. Ancient trees, being physiologically active throughout the year, play a significant role in enriching the atmosphere with oxygen through photosynthesis [3]. The tree microbiome consists of microorganisms (bacteria and micromycetes) inhabiting the roots, stems, and leaves, along with their genetic material. Some microorganisms enhance the physiological processes of trees and increase their resilience to environmental stresses such as drought and extreme temperature [4]. The composition of the microbiome is influenced by factors such as tree age, soil properties, climate, and humidity [5]. In recent decades, infections of ancient and ornamental trees by various phytopathogenic microorganisms have been increasing due to adverse climatic and abiotic factors [6]. This not only poses a threat to trees but also contributes to the rise of allergic diseases in humans, thus representing a serious environmental risk [7]. Pathogenic microorganisms alter plant physiology and metabolism, leading to diseases. They may exist on plant surfaces as epiphytes or within tissues as endophytes, occupying intercellular spaces [8]. Endophytic and epiphytic microorganisms can be either beneficial and symbiotic or phytopathogenic, causing plant diseases [9]. Endophytic microorganisms include diverse ecological groups such as root and soil endophytes [10]. Some endophytes may shift between mutualistic and latent pathogenic stages during their life cycle [11, 12]. Therefore, endophytes exhibit multiple functional characteristics at different life stages. The use of antagonistic endophytic microorganisms is one of the most effective biological control strategies against plant pathogens [13, 14]. Endophytes are also promising sources for developing biological preparations and bioactive compounds such as alkaloids, cytochalasins, polyketides, terpenoids, flavonoids, and steroids [15–17]. These substances have great potential for application in medicine, agriculture, and industry. Considering the vast plant diversity worldwide, endophytic micromycetes are a valuable source for discovering new natural biological control agents [18]. Microorganisms are dispersed through soil, water, air, and various anthropogenic factors. When soil conditions change, saprophytic microorganisms can multiply rapidly [19]. The phytopathogenic micromycete Rhizoctonia solani, which causes various plant diseases, was isolated and its morphological characteristics studied. In laboratory conditions, the pathogenic properties of most isolated phytopathogenic microorganisms were confirmed [20]. Soil microbial populations often include bacterial genera such as Pseudomonas, Bacillus, and Pasteuria, which have strong potential for biological control of nematode populations [21]. Promising results were also obtained from experiments using biological control agents against Pantoea agglomerans, the causal agent of fire blight. Following these studies, the mechanisms of antagonist activity were examined in detail [22]. To develop effective biological control methods and create environmentally friendly biological agents, it is necessary to isolate antifungal and antibacterial antagonist strains from ancient trees [23]. However, current research on endophytic microorganisms remains limited, leading to the spread of diseases caused by them. Therefore, studying the diversity of endophytic and epiphytic microorganisms and their potential effects on tree species and human health is of great scientific importance. Research Area and Methods The research was conducted in the area surrounding the Ulugbek Observatory and Sherdor Madrasah in Samarkand, Uzbekistan. The Ulugbek Observatory, built in 1428–1429 on Choponota Hill near the Obirakhmat stream, is one of the rare examples of 15th-century architecture. Around the observatory, ancient plane trees (Platanus orientalis) are found. The Sherdor Madrasah, located on Registan Square, dates to the 17th century and was included in the UNESCO World Heritage List in 2001. Around this monument grows an ancient Juniperus virginiana (Virginia juniper), also known as pencil cedar, which was planted in 1873 and is notable for its evergreen foliage. Plant samples were collected aseptically from the bark, branches, leaves, flowers, and immature fruits of several ancient trees near these monuments — including Pinus nigra, Picea pungens Engelm., Pinus eldarica Medw., Aesculus sp., and Morus sp. (near the Ulugbek Observatory), and Thuja orientalis, Juniperus virginiana, Pinus sylvestris, Juniperus sp.1, and Morus sp. (around the Sherdor Madrasah). Samples were taken from a total of six trees near the Ulugbek Observatory and eight trees near the Sherdor Madrasah. A seasonal study revealed that microbial activity was highest in spring, while lower levels were observed in summer and autumn. In the laboratory, all procedures were performed in a biological safety cabinet (BSC-1300IIA2-X). To isolate epiphytic microorganisms, plant material was first treated with 3% hydrogen peroxide for 15 minutes and then rinsed ten times with sterile distilled water. Small tissue sections were excised using sterilized scalpels and tweezers and inoculated onto potato dextrose agar (PDA) plates. To isolate endophytic microorganisms, plant samples were covered with sterile quartz sand in porcelain dishes and inoculated into PDA medium. The inoculated samples were incubated at temperatures ranging from 20°C to 36°C (Figure 1) Figure 1. Samples taken from the Ulugbek Observatory and Sherdor Madrasah and colonies of microorganisms that developed in the samples. From the 2nd day of the study, the formation, that is, the development of bacterial and micromycete colonies was observed in the samples planted. Data analysis: The results obtained were identified using generally accepted methods in microbiology, genetic and MALDI-TOF MS methods. Pure isolates were isolated by re-sowing microorganisms on nutrient media (Figure 2). When studying the developed microflora from samples taken from trees, the samples obtained were incubated on the above nutrient media for 6-7 days. To isolate pure cultures from the samples, the generally accepted method of re-sowing on PDA nutrient media was used. In the next stage of the study, studies were conducted on the isolation of pure cultures from the colonies of microorganisms that developed in the samples. Figure 2. Results of the study conducted in laboratory conditions. A-Bacterial isolates isolated from samples taken from Sherdor madrasah; B-micromecit isolates; C-Bacterial isolates isolated from samples taken from Ulugbek Observatory; D-micromecit isolates; In order to identify the types of pure isolates, the morphological characteristics of the microorganisms were examined. … Read more

Medicinal Plant Diversity and Traditional Knowledge Among Ethnic Groups in Burkina Faso Central-West Region

  • Dramane Kabore
  • Adama Rama
  • Renan Ernest Traore

Introduction Medicinal plants constitute a cornerstone of traditional healthcare systems globally, particularly in developing countries where access to modern medical services remains limited [1]. In sub-Saharan Africa, approximately 80% of rural populations continue to rely on plant-based resources for disease prevention and treatment [2] [3]. Beyond their therapeutic value, these plants represent a significant component of cultural heritage, transmitted orally across generations [4]. In Burkina Faso, traditional medicine is largely grounded in the use of a diverse array of medicinal plant species [5]. However, anthropogenic pressures, deforestation, declining plant biodiversity, and the globalization of lifestyles are accelerating the erosion of this ancestral knowledge [6] [7]. In this context, the documentation and valorization of local ethnobotanical knowledge are critical for both the conservation of medicinal plant species and the intergenerational transmission of traditional practices [8]. The Central-West region of Burkina Faso, characterized by rich floristic diversity and a long-standing tradition of medicinal plant use, remains insufficiently studied from an ethnobotanical perspective [9]. Recording the species employed and the associated knowledge is essential not only for biodiversity conservation but also for supporting the integration of traditional pharmacopoeia into local healthcare strategies [1] [3]. This study aims to inventory the medicinal plant species used in the Central-West region of Burkina Faso and to analyze the diversity and therapeutic applications of these taxa. Materials and Methods Study Area and Surveyed Population The survey was conducted in 30 villages located within the Boulkiemdé and Sanguié provinces, in the Central-West region of Burkina Faso (Figure 1). These sites were selected based on criteria such as accessibility, ethnic diversity, and their recognized role in the transmission of traditional knowledge related to medicinal plant use. The participants included a wide range of individuals, primarily traditional healers, herbalists, folk medicine practitioners, and elderly persons acknowledged for their expertise in traditional pharmacopoeia. Data Collection Data were collected using three complementary methods: semi-structured interviews, direct observations, and botanical specimen collection. Semi-structured interviews were conducted with traditional healers, herbalists, and other local knowledge holders. An interview guide was used to gather information on the medicinal plant species used, plant parts utilized, preparation methods, treated ailments, and conservation practices. Direct observations were carried out at collection sites, in local markets, and within households to document actual practices related to the use and management of medicinal plants. Specimen collection was conducted with the assistance of informants. Plant samples were harvested, pressed, and transported to the laboratory for identification. The identification process was based on regional floras and standard reference works [10] [11]. Data Analysis Statistical Analysis All statistical and graphical analyses were performed using RStudio version 4.5.1, according to the requirements for processing, structuring, and visualizing the ethnobotanical survey data. Absolute and relative frequencies were calculated to describe the socio-demographic characteristics of the respondents. The Use Value (UV) of each plant species was computed following the formula proposed by [12]: Ui represents the number of use reports mentioned by informant i, and N is the total number of informants. This index serves to assess the relative importance of a plant species within traditional medicinal practices. In addition, the Relative Frequency of Citation (RFC) was calculated to measure the proportion of informants who cited each species, using the formula: FC is the number of citations for a given species, and N is the total number of participants. To explore the diversity of dosage types and administration times associated with the therapeutic uses of plants, heatmaps were generated based on binary or frequency-weighted occurrence matrices. Finally, the integrated structure of traditional therapeutic knowledge was visualized using a circular network diagram (chord diagram), linking plant species, ethnic groups, preparation methods, and types of treated ailments. This graphical representation illustrates the density of interconnections within the traditional medicinal system and highlights the central species in the network of ethnomedical knowledge. Results Socio-demographic Characteristics of Respondents Data analysis highlights two key aspects of the respondents’ profiles: age and educational level. Regarding age distribution, the majority of participants, representing 67%, were aged 50 years and above, while 33% were under 50 years. This demographic structure indicates a strong representation of elderly individuals within the sample. Concerning educational attainment, a large proportion of respondents (72.1%) had no formal schooling. Only 18.9% reached the primary education level, and 9% attained secondary education. This low level of education reflects a generally limited educational context among the majority of participants (Table 1). Use Value of the Studied Plant Species The most utilized species is Euphorbia hirta, which recorded the highest use value (UV = 0.737). This high score reflects both a significant frequency of use and a notable diversity of applications reported by informants. A group of species exhibited intermediate use values, with a UV of 0.368. These include Ximenia americana, Vitex cuneata, Spondias mombin, Detarium microcarpum, and Acacia macrostachya. These plants are also well established in the local pharmacopoeia, suggesting their recognized utility in traditional practices. Other species fall within a moderate use value category, with UVs ranging from 0.274 to 0.342. Among these are Guiera senegalensis, Combretum paniculatum, Diospyros mespiliformis, Terminalia avicennioides, and Nauclea latifolia. Finally, the least cited species are Gardenia erubescens, with a UV of 0.221, and Piliostigma thonningii, which has the lowest use value in the studied panel (UV = 0.132), indicating a lesser importance in the reported medicinal uses (Figure 2). Relative Frequency of Citation (RFC) of the Studied Species The graph presents the relative frequency of citation (RFC) of various medicinal plant species, an indicator measuring the importance and frequency of use of each plant within traditional medicine practices. Euphorbia hirta is the most cited species with an RFC of 0.15. This high value reflects its central importance in ethnobotanical knowledge and suggests widespread use in treating diverse ailments. Diospyros mespiliformis ranks second with an RFC of 0.10, also indicating significant recognition in local medicinal applications. A group of ten species shows intermediate RFC values, each around 0.07. These include Ximenia americana, Vitex cuneata, Spondias mombin, Detarium microcarpum, Acacia macrostachya, Terminalia avicennioides, Nauclea latifolia, Guiera senegalensis, … Read more

Optimized Water-Agar Assay for Tomato Seed Vigor Enables High-Fidelity Plant Growth Regulator Screening

  • Mahesh R. Ghule1
  • Monika C. Narayankar2
  • Priti B. Panchal2
  • Kirti T. Kamthe3
  • Adwait K. Kamthe1
  • Sunita S. Sakure2

Introduction Tomato (Solanum lycopersicum L.), a member of the Solanaceae family, is one of the world’s most important vegetable crops, valued for its economic, nutritional, and scientific significance. Originating in western South America, tomato cultivation has expanded globally and today ranks as the second most produced vegetable after potato by volume [1, 2, 3]. In 2022, global tomato production reached ~186.8 million metric tons across 5 million hectares, underpinning a multi-billion-dollar industry that spans fresh produce and processed products such as sauces and pastes [4]. Nutritionally, tomatoes are low in calories but rich in vitamins A, C, and K, minerals, dietary fiber, and phytochemicals, most notably lycopene. Lycopene is a potent antioxidant linked to reduced risks of cardiovascular diseases and several cancers [5, 6, 7, 8]. This combination of agricultural, economic, nutritional, and health value has also made tomato a model organism for studies in genetics, physiology, and biotechnology [1, 9]. Successful and uniform crop establishment begins with seed quality. While viability defines the inherent ability of a seed to germinate, vigor is a superior predictor of performance under diverse and stressful field conditions [10, 11]. Seed vigor is characterized by rapid, uniform germination and robust seedling development. Standard germination tests (SGTs), such as those prescribed by ISTA and AOSA, measure maximum germination potential under optimal conditions [12]. However, these conditions rarely reflect field realities, and SGTs often overestimate emergence capacity. Even weak or damaged seeds may germinate in the laboratory yet fail in the field [10, 13]. To bridge this gap, seed vigor testing has become an essential component of seed quality assessment [14, 15]. For tomato, high vigor is critical for field establishment and yield uniformity [16]. The rolled paper towel (PT) method is widely used for SGTs due to its low cost and simplicity. However, it presents limitations for vigor testing and sensitive applications such as plant growth regulator (PGR) screening. Moisture regulation in PT is inconsistent: excessive wetness can create anaerobic conditions leading to seed rot, while drying can arrest germination. In addition, seedling radicles often entangle within the paper matrix, causing damage during measurement and increasing variability [17, 18]. The opaque, rolled setup further prevents real-time observation of germination. Studies have shown that agar-based substrates generate more uniform seedlings than paper or sand [19]. Water-agar (WA), a sterile, semi-solid, nutrient-free medium, provides several advantages. It offers stable and uniform moisture, prevents substrate entanglement, and allows continuous, non-invasive observation of germination. However, agar concentration critically influences water potential and gel firmness. Higher agar concentrations reduce water availability by lowering matric potential, imposing resistance to root penetration and creating physiological drought [20, 21]. Conversely, excessively low concentrations may cause free water release or hypoxia [22]. Hydrothermal modeling further confirms that water × temperature interactions strongly regulate germination dynamics [23, 24]. Thus, optimizing agar concentration is essential for accurate assessment of seed vigor. This study aimed to (1) optimize agar concentration for tomato seed germination and vigor, and (2) compare the optimized WA method with the PT method for high-fidelity screening of tomato seed responses to two PGRs indole-3-butyric acid (IBA) and gibberellic acid (GA₃). Materials and Methods Plant Material and Sterilization Seeds of tomato (S. lycopersicum cv. Seminis Abhilash, Bayer Crop Science, India) were used. Seeds were stored at 4 °C in airtight containers. For sterilization, seeds were immersed in 70% ethanol for 1 min, followed by 1.5% sodium hypochlorite with Tween-20 for 10 min, and rinsed five times with sterile distilled water. Experiment 1: Optimization of WA Concentration A completely randomized design (CRD) tested six substrates: sterile distilled water (0% agar) and agar concentrations of 0.13, 0.25, 0.50, 1.0, and 2.0% (w/v). Agar (HiMedia, India) was autoclaved (121 °C, 20 min) and poured into sterile 6-well plates (10 mL/well). After solidification, 10 sterilized seeds were placed per well (100 seeds/treatment). For 0% agar, 10 mL sterile water was used. Plates were sealed with Parafilm, incubated at 25 ± 2 °C under a 16 h dark/8 h light regime (ISTA protocol) [12]. Experiment 2: Comparative Analysis of WA vs. PT for PGR Screening A factorial CRD design compared WA (0.5% agar, from Experiment 1) with PT across six concentrations each of IBA (0, 10, 25, 50, 100, 200 mg/L) and GA₃ (0, 50, 100, 200, 400, 800 mg/L) [25, 26, 27]. WA method: PGRs were filter-sterilized and incorporated into molten 0.5% agar. Ten mL medium was dispensed per well, with 10 seeds/well. PT method: Two sterile germination papers were moistened with PGR solution, seeds placed, rolled, and enclosed in polyethylene bags. Each treatment had 10 replicates (100 seeds). Incubation conditions were as in Experiment 1. Data Collection In Experiment 1, germination was recorded daily for 14 days. A seed was considered germinated when radicle length ≥2 mm [12]. Final germination %, mean germination time (MGT), shoot/root length, seedling length, seedling vigor index (SVI = germination % × mean seedling length), fresh weight, dry weight, and biomass gain were recorded. In Experiment 2, germination was assessed on day 7. Shoot and root length, SVI, and qualitative differences between WA and PT seedlings were recorded. Coefficients of variation (CV) for shoot/root length were calculated. Statistical Analysis Data were analyzed by one-way ANOVA (Experiment 1) and two-way ANOVA (Experiment 2) with Tukey’s HSD test (P ≤ 0.05). Data normality and homogeneity were verified; no transformation was required. Analyses were performed using R v4.1.2. Results and Discussion Water-Agar Concentration Optimization for Seed Vigor WA substrates consistently outperformed the water-only control, which was limited by hypoxic stress. The 0.5% WA medium proved optimal, achieving 95% germination and the highest vigor index, consistent with earlier reports on tomato seed vigor under controlled water potential [11,24,29,31]. In the water-only treatment (0% WA), germination was significantly lower and slower than in any agar-containing medium (Table 1). After 14 days, the control reached only ~62% germination, compared with 82–95% across WA treatments. Seeds germinated in water required considerably more time (MGT ≈ 6.3 days) and produced weak seedlings averaging ~23 mm in total length, which … Read more

An Assessment of Rural Households Perception of Climate Change in Taraba State, Nigeria

  • Oruonye, E.D.1
  • Ojeh Vincent Nduka1
  • Linda Sylvanus Bako1
  • Ezra, A.2

Introduction Climate change represents one of the most pressing global challenges of the 21st century, affecting the environment, economies, and societies in multifaceted ways. Its impacts are disproportionately felt in developing regions, particularly in sub-Saharan Africa, where livelihoods are largely dependent on climate-sensitive sectors such as agriculture and forestry [1]. Nigeria, as Africa’s most populous nation, faces significant climate-related risks including rising temperatures, irregular rainfall patterns, prolonged droughts, and increasing incidences of flooding. These changes threaten food security, water availability, and health, particularly in rural areas where adaptive capacity is generally low [2]. Taraba State, located in the northeastern region of Nigeria, exhibits a diverse agro-ecological landscape comprising the Sudan Savannah, Northern Guinea Savannah, Southern Guinea Savannah, and Montane zones. These zones are home to numerous rural communities whose livelihoods are intricately tied to natural systems. Consequently, any alteration in the climate system has profound implications for their socio-economic well-being. Despite the evident impacts of climate change, understanding how rural populations perceive these changes remains limited. This knowledge gap is critical because perception influences response and adaptation strategies at the community level [3]. Perceptions of climate change among rural populations are shaped by various factors including ecological location, cultural beliefs, religious orientation, and direct environmental experiences. In some rural Nigerian contexts, changes in climate are not solely attributed to scientific or physical causes but are often linked to spiritual or moral explanations such as divine punishment for societal wrongdoing [4]. Understanding these perceptions is essential for designing context-specific climate change communication and adaptation strategies that are both culturally sensitive and scientifically sound. Although several studies have examined the physical manifestations of climate change in Nigeria, few have focused on local perception, especially in ecologically diverse states such as Taraba. Assessing rural households’ perception is not only important for enhancing scientific knowledge but also for informing policy and grassroots action plans aimed at building resilience to climate shocks. Perception studies can help identify knowledge gaps, promote behavior change, and improve the targeting of adaptation interventions [5]. This study, therefore, seeks to assess rural households’ perception of climate change in Taraba State, Nigeria. It aims to explore how rural residents interpret the causes of climate change, the extent to which their perceptions differ across agro-ecological zones, and the socio-cultural and environmental factors influencing these perceptions. By doing so, the study contributes to a deeper understanding of local environmental cognition and supports the development of tailored climate adaptation policies. Statement of the Research Problem Climate change continues to pose an existential threat to global development, with its impacts disproportionately affecting vulnerable populations, especially in rural and ecologically diverse regions of sub-Saharan Africa. In Nigeria, where over 70% of the population depends on climate-sensitive activities such as agriculture and natural resource extraction, the rural populace remains at the frontline of these environmental challenges [2]. Taraba State, characterized by complex agro-ecological zones and a largely rural demographic, is particularly vulnerable due to its dependence on rain-fed agriculture, extensive deforestation, and low adaptive capacity. Despite increasing scientific evidence and global awareness of climate change, there remains a significant gap in understanding how rural communities in Nigeria, particularly in Taraba State, perceive the phenomenon. Perception is a key determinant of climate response; it shapes risk appraisal, decision-making, and local adaptation strategies [3, 5]. However, rural perceptions are often influenced not only by direct environmental experiences but also by cultural, religious, and social interpretations. For instance, earlier findings suggest that some rural households in Taraba State attribute climate change to spiritual causes such as divine punishment rather than scientific explanations such as greenhouse gas emissions or land use change [4, 6]. This divergence in perception may result in limited acceptance or misalignment with formal climate change communication and mitigation initiatives. Moreover, variation in perception across ecological zones may further complicate policy formulation and implementation. Without a clear understanding of how rural households interpret climate change and its causes, efforts to promote adaptation and resilience-building at the community level risk being ineffective or culturally inappropriate [1]. While existing studies in Nigeria have predominantly focused on the biophysical impacts of climate change or macro-level vulnerability assessments, little empirical research has been conducted to capture the nuanced, localized perceptions of rural households in Taraba State. There is, therefore, a compelling need to examine these perceptions systematically, identify their socio-cultural and ecological drivers, and assess the extent to which they align with scientific understanding. This study addresses this critical gap by assessing rural households’ perception of climate change across the four agro-ecological zones of Taraba State. It provides evidence-based insights necessary for designing culturally sensitive and geographically targeted climate adaptation policies and education programs. Description of the Study Area Taraba State, located in the northeastern region of Nigeria, lies between latitudes 6°30′N and 9°36′N and longitudes 9°10′E and 11°50′E (Fig. 1). It shares international boundaries with the Republic of Cameroon to the east and national boundaries with Bauchi, Gombe, Adamawa, Benue, Nassarawa, and Plateau States. With a land area of approximately 54,473 square kilometers, it ranks among the largest states in Nigeria by landmass [7]. Taraba State exhibits diverse topographical and ecological characteristics shaped by its position on the windward side of the Cameroon Highlands. The state’s landscape ranges from low-lying plains in the north to high-altitude mountainous terrains in the southeast, notably in the Mambilla Plateau region which rises to over 1,800 meters above sea level. This ecological variability contributes to its classification into four major agro-ecological zones: the Sudan Savannah, Northern Guinea Savannah, Southern Guinea Savannah, and the Montane zone. These ecological zones influence not only the state’s biodiversity and agricultural productivity but also how communities experience and respond to climate-related changes. For instance, the Montane zone experiences cooler temperatures and higher rainfall, while the Sudan Savannah in the north is drier and more prone to desertification and drought. The state experiences a tropical climate, with two distinct seasons: the rainy season (April to October) and the dry season (November to March). Annual rainfall varies between 800 mm in … Read more

Response of wheat plants (Tritium astrium L.) to NPK Nano fertilizer under saline soil conditions in Nineveh Governorate

  • Hind Awad Sabbar
  • Khalid Ekhlayef N. Alhadidi
  • Rana Saadallah Aziz

Introduction      Wheat is an essential source for the production of bread in many countries of the world. It is also considered an important source of proteins, calories, fats, vitamins, and mineral salts [11]. Wheat protein contains approximately 35% gluten, which helps in producing good types of bread compared to the resulting of bread. Among other grain crops, the wheat crop is also used in the production of some medicines, while wheat waste is used as animal feed. Because of the importance of the wheat crop and its nutritional role, it is called the king of grains , Nano fertilizer technology is one of the recent discoveries that provides solutions to many problems in the agricultural field [15]. Nano refers to a unit of measurement that denotes one billionth (10-9) of a meter. Nanotechnology means the technology of extremely small materials. Or microscopic technology. Scientists and engineers deal with matter at this scale at the level of atoms and Nanoparticles [25]. The Nano unit is used to measure microscopic particles, atoms, and diameter dimensions [2]. The difference in the behavior of Nanomaterials is due to two basic factors: The first factor is the increase in area. The surface area of ​​the material, which will lead to an increase in the specific surface area, so the interaction of the material increases, and then its chemical activity becomes higher [8]. The second factor is the quantitative effects in these Nanomaterials, and because of their small dimensions, they are not subject to the laws of classical physics, but they are subject to the laws of quantum physics, so they affect… in their properties, which is reflected in the optical, electrical, magnetic and mechanical behavior of materials [14].      Salinization is the process of gathering or accumulating dissolved salts to a degree exceeding their natural rates in the soil. The cause of salinization may be natural or due to conditions resulting from poor management processes [6]. Saline soils are characterized by chemical, physical, biological, and morphological characteristics different from non-saline soils. They are also characterized by a predominance of Certain types of cations and anions [19]. The area of ​​land affected by salts reached (340 million hectares) at the global level, while the area of ​​sodic lands reached (560 million hectares). Salinity, in addition to the osmotic effect, is an ionic effect that is often associated with high levels of sodium to potassium (K+ /Na+) and sodium to calcium ( Ca++ /Na+), magnesium to calcium (Ca++ /Mg++), and chloride to nitrate (NO3 / Cl-), which means the accumulation of both sodium and chloride in the plant tissue in addition to the soil, which affect water stress and cause the absorption of the main nutrients to be affected. Interactions, ionic competition, or influence the integrity of the cell membrane [27]. Sodium competes with potassium, calcium, and magnesium, in addition to manganese, and reduces the amount available to the plant or replaces the calcium ion in the binding sites in the cytoplasmic membranes, which negatively affects their selective property, while chloride restricts the absorption of nitrates and phosphates in addition to sulfates [20]. Materials and Methods Collecting soil samples and preparing them for study:     Three sites were chosen from Nineveh Governorate within the (Tel Abta) area due to the importance of these sites from an agricultural standpoint as they are grown with grain crops and irrigated supple mentally depending on the difference (rainfall range, vegetation cover, variation in salt distribution). Excited samples were taken at a depth of (0 – 30) cm. On 10/5/2023 from the study sites, Table (3), samples were taken to prepare them for cultivation for analyzes and laboratory studies according to the methods mentioned in [22]. Chemical and physical analyses  The soil extract (1:1) was used to estimate dissolved ions. The electrical conductivity (EC) and the degree of soil reaction (pH) were measured using the WTW Multi 4001 device [20]. Calcium and magnesium were calibrated with (0.01N) of ferricin (EDTA di -Na) [20], I use a Shewood model 410 flame photometer to measure both sodium and potassium in the soil extract after adjusting the device with standard solutions and based on [26], carbonates and bicarbonates by calibration with (0.01N). Of sulfuric acid and using the phenolphthalein index to estimate carbonates and the methyl orange index in the case of bicarbonate. Chlorides were estimated by titration with (0.01N) of silver nitrate (AgNO3 [26]. Sulfates were calculated from the difference between the sum of dissolved positive ion equivalents and dissolved negative ion equivalents [22], organic matter was estimated by the wet oxidation method using potassium dichromate (K2Cr2O7) [20], total carbonates (lime) were estimated by titration method with hydrochloric acid at a concentration of (1M) phenolnaphthalene index [10], it was Gypsum was estimated by the acetone precipitation method according to the method used by [18]. The hydrometer method was used to estimate soil separations of clay, silt, and sand, according to what was mentioned by [13]. The bulk density was estimated by the paraffin wax method [17]. Implementation of the experiment  Plastic pots with a diameter of (25 cm) and a depth of (35 cm) were filled with (7) kg of air-dry soil and sifted through a sieve with a diameter of (4 mm). (10 seeds) of wheat variety (durum desf) were planted in each pot at a depth of (1 cm) from the soil surface, taking into account the selection of healthy seeds of similar sizes. After (10) days of planting, the plants thinned to only three plants per pot. As for the irrigation process, the experimental plants will be placed below 75% of the field capacity of the soil, using water (the Tigris River) throughout the experiment period, and the irrigation process will be conducted using the gravimetric method by weighing each pot and then adding water to the pot for the purpose of obtaining the wet weight. Experiment design: The experiment will be implemented according to a completely randomized design with three replications as a factorial experiment with three factors: … Read more

Triticale Varieties: The Effect of Fertilizer Rates on Changes in Leaf Pigment Content

  • Maftuna Raimqulova1
  • Akmal Sanakulov1
  • Mahliyo Usmonova2

Introduction Nowadays, the rapid growth of the world population is leading to an increased global demand for food. As a result, the need for plant-based products is also rising. In this context, special attention is being paid to the evaluation and application of the physiological and biochemical characteristics of new plant species with high productivity and nutritional potential, especially in arid and water-deficient regions. Research conducted in this direction is considered a solution to some of the most important and urgent problems. Therefore, studies aimed at producing high-quality, low-cost, and environmentally friendly agricultural products are among the most pressing issues today [1, 2]. Triticale (× Triticosecale) is a man-made cereal crop developed by crossing wheat and rye [2]. The name “Triticale” is derived from the combination of the scientific names of wheat (Triticum) and rye (Secale) [6]. The first hybridization was carried out in the late 1870s in Scotland, and the first fertile wheat–rye amphidiploids were obtained in 1888 by the German scientist Rimpau. A widespread triticale improvement program began in 1964, and today it is considered the main supplier of improved germplasm for national and international programs worldwide [11, 3, 8]. Triticale is a crop that is resistant to adverse environmental conditions, diseases, and high temperatures, and it adapts well to unfavorable soils and climates [5, 13]. Currently, triticale occupies a strong position in agricultural production across various countries [4]. It is mainly cultivated for grain feed and green fodder. However, in recent years, triticale grain has increasingly been used in the food and alcoholic beverage industries [7]. Photosynthesis occurs primarily in green leaves, and to a lesser extent in young shoots and unripe fruits, due to the presence of chloroplasts. Pigments found in plant tissues play a vital role in this process. In particular, chlorophylls are directly involved in all primary reactions of photosynthesis [9, 15]. Literature Review In Uzbekistan, research on cultivating autumn triticale as a forage crop on irrigated lands, including studies on optimal sowing times, seeding rates, and fertilizer norms, has been conducted by I.V. Massino (1989). On rainfed lands, studies by M. Khayitboev (2019) and K.T. Isokov (2020) have focused on developing early-maturing breeding materials to ensure stable yields. J. Doschanov (2021) and colleagues have assessed the salt tolerance of triticale cultivars, highlighting growing scientific interest in this crop. Several foreign and CIS scientists have also made significant contributions to triticale research. These include P. Gupta (1982), M. Mergoom (2004), A. Blum (2014), R. Agil (2014), E. Arseniuk (2015), and V.Yu. Kovtunenko (2019). In the CIS, contributions have been made by A.I. Grabovets (2000), N.V. Rogozhkina (2006), N.N. Zezin (2010), S.A. Gorchin (2012), T.A. Goryanina (2017), N.P. Shishlova (2018), and B.B. Boronchikhin (2019). Research Object and Applied Methods The triticale cultivars Odyssey and Sardor were selected as the experimental objects. The study was conducted under field conditions in the Samarkand region during the 2024–2025 growing seasons. All analyses, phenological observations, and calculations were carried out in accordance with established methodological guidelines. The content of pigments in the leaves was determined using the method developed by V.F. Gavrilenko, M.E. Ladigina, and L.M. Khandobin, utilizing an SF-26 spectrophotometer. Results and Discussion Chlorophyll a and b are considered the primary pigments involved in the photosynthesis process. Additionally, carotenoid pigments—yellow, orange, and red—are present and play key roles in various physiological functions. Carotenoids protect plants from harmful environmental factors and help transfer short-wavelength light energy to chlorophyll molecules [12, 14, 16]. It was found that the content of plastid pigments and carotenoids in the leaves of triticale cultivars Odyssey and Sardor varied depending on the nitrogen fertilizer rates. The experimental data are presented in Tables 1 and 2. The amount of plastid pigments in fresh triticale leaves changed across the different growth stages. Total chlorophyll content increased from the tillering stage to the flowering stage, then decreased during the grain ripening stage. It was also revealed that the amount of chlorophyll a was higher than that of chlorophyll b in both triticale cultivars studied. Content of plastid pigments (mg/g) in the leaves of the Sardor cultivar at different growth stages The amount of carotenoid pigments was initially lower than that of chlorophyll a and b, but it gradually increased throughout the vegetation period. In the Sardor cultivar of triticale, during the tillering stage, total chlorophyll content varied across treatments from 4.31 mg/g to 5.12 mg/g. Chlorophyll a ranged from 2.52 mg/g to 2.99 mg/g, while chlorophyll b ranged from 1.79 mg/g to 2.13 mg/g. Carotenoid content varied from 1.51 mg/g to 1.84 mg/g depending on the fertilizer treatment. The ratio of total chlorophyll (a + b) to carotenoids ranged between 2.85 and 2.93. During the stem elongation stage, the total chlorophyll content in the Sardor cultivar increased, ranging from 4.69 mg/g to 5.91 mg/g. Chlorophyll a content ranged from 2.81 mg/g to 3.22 mg/g, and chlorophyll b from 1.88 mg/g to 2.69 mg/g. Carotenoid content was lowest in the control (1.57 mg/g) and highest in the N300 P210K150 treatment (1.92 mg/g). Intermediate values were observed in the other variants. The chlorophyll a + b to carotenoid ratio ranged from 2.98 to 3.07. At the heading stage, further increases in pigment content were recorded. Chlorophyll a was lowest in the control (3.04 mg/g) and highest in N300 P210K150 (3.56 mg/g). Chlorophyll b ranged from 2.34 mg/g (control) to 2.75 mg/g (N300 P210K150). Carotenoid levels remained lower than those of chlorophylls, ranging from 1.61 mg/g to 1.99 mg/g. Total chlorophyll content increased from 5.38 mg/g (control) to 6.31 mg/g (N300 P210K150). The ratio of total chlorophyll (a + b) to carotenoids ranged from 3.11 to 3.34. During the flowering stage, total chlorophyll content reached its peak compared to the other growth phases. In all treatments, pigment content increased. Total chlorophyll levels were 5.53 mg/g in the control (0.15 mg/g higher than at the heading stage), 5.87 mg/g in N150P105K75 (+0.26 mg/g), 6.36 mg/g in N200 P140K100 (+0.30 mg/g), 6.13 mg/g in N250 P175K125 (+0.49 mg/g), and 6.59 mg/g in … Read more

Performance evaluation of aggregatum onion genotypes (Allium cepa var.aggregatum) for yield and quality under Coimbatore conditions in Tamil Nadu

  • Usha Nandhini Devi Harinarayanan1
  • Pugalendhi Lakshmanan2

1.Introduction Aggregatum group includes shallots and potato onions and are referred to as multiplier onions. The bulbs are smaller than those of common onions, and a single plant forms an aggregate cluster of several bulbs from a central bulb. They are propagated commercially from daughter bulbs, and varieties which set seeds under TamilNadu conditions are propagated through seeds. Shallots are the most important subgroup within this group and comprise the only cultivars cultivated commercially. They form aggregate clusters of small, narrowly ovoid to pear-shaped bulbs. Potato onions differ from shallots in forming larger bulbs with fewer bulbs per cluster, and having a flattened (onion-like) shape. Intermediate forms exist [5]. Diversity in plant genetic resources offers plant breeders the opportunity to develop novel and better cultivars with desirable characteristics, which include both farmer-preferred traits like yield potential and larger bulbs and breeder-preferred traits which include pest and disease resistance and photosensitivity [6]. The conservation of germplasm is necessary for maintaining genetic diversity, studying local genetic material and under-utilized species, and to choose species suitable for developing newer varieties [3]. No country in the world is self-sufficient in germplasm to fulfill its food requirements. Many countries predominantly depend on nonindigenous crops and imported germplasm for food and agricultural development [4]. Aggregatum onion (Allium cepa var. aggregatum) is mainly grown in Tamil Nadu, Andhra Pradesh and Karnataka. In TamilNadu it is cultivated in an area of 30,000 ha. It is well known for its use in sambar preparation, an important South Indian dish. It has demand in the international market due to its unique taste and flavor. Inorder to identify genotypes which perform better in terms of quality and yield, this study has been undertaken to evaluate the performance of genotypes available. 2.Materials and methods The present study was conducted at the College Orchard of the Department of Vegetable Science, Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore during 2021-2022. A total of 65 genotypes maintained at the Department of Vegetable Science were evaluated for yield, quality parameters, and disease index. (Table.1) The experiment was laid in randomized block design with two replications. The package of practices as recommemded by the crop production guide of TamilNadu was followed. Observations were recorded on Average bulb weight (g), Total Soluble Solids (%), Total Yield (t/ha),thrips damage(%), leaf spot (PDI) and Stemphyllium blight (PDI). Ten plants were randomly selected from each plot for recording data and the average was calculated. After curing, the total bulb fresh weight was measured for each plot. The total soluble solids (TSS) content of bulbs were recorded by hand refractometer. The disease (leaf spot and Stemphyllium blight) severity of onion was scored by following 0-5 scale, as described by [8]. The details of scales are as follows: 0-no disease symptoms, 1- a few spots towards tip covering 10% leaf area, 2- several dark purplish brown patch covering up to 20% leaf area, 3- several patches with paler outer zone covering up to 40% leaf area, 4- leaf streaks covering up to 75% leaf area or breaking of the leaves from center and 5- complete drying of the leaves or breaking of the leaves from the centre. Likewise, thrips infestation was also rated by following 0-5 scale. Observations were made at the first appearance of disease symptoms/thrips on plants, till the harvest at weekly intervals. Color of bulbs were identified by visual assessment method. 3.Results and Discussion The genotypes used in the study exhibited a wide range of differences in the parameters measured. The observations recorded are given in Table 2. 3.1. Bulb weight There were significant differences in bulb weight among the different genotypes (Table 2). The heaviest bulb weight (66.2g) was observed in the genotype Agg-Sel-1 followed by followed by Agg-Sel-3 with 64.4g. The lightest individual bulb (33.2 g) was observed in Agg-1519. The difference in bulb weight could be attributed to the genetic potential of the different genotypes. The results of the present study confirms with the findings of [9]. 3.2.Total soluble solid content The total soluble solids (TSS) content differed significantly among. The highest percent of Total Soluble Solids (15.3) was recorded in Agg1552 followed by Agg 1535 with 15.2% and Agg-Sel-4 with 15.0%. The lowest TSS content (7.0%) was observed in 1548-Agg.The variation in TSS content among the genotypes might be attributed to differences in the genetic potential of the genotypes used in the study. This is following the results of [1]. 3.3.Yield The genotypes expressed significant variation in yield per hectare. The genotypes, Agg 1522 and Agg 1692 recorded a total yield of 17.4t/ha which was higher than all other genotypes. The lowest yield per hectare (6.80t/ha) was observed in Agg-Sel-43 followed by Agg 1523 with 10.5t/ha. The superior performance of the genotypes could be due to their higher individual bulb weight. Similar results have been obtained by [2,7,10]. 3.4.Skin and flesh colour of the bulb  The result of color measurement revealed that there was not much variation in the skin colour of the bulbs among the different genotypes evaluated. 3.5.Disease incidence and thrips infestation The genotypes evaluated also showed significant differences for disease scoring. The lowest percent of thrips (12.5) was observed in Agg 1528, the lowest leaf spot incidence was observed in Agg1532 with 11.5 and the lowest incidence of Stemphyllium blight was recorded in Agg-Sel-2 with 3.7.The apparent cause of the variation in disease severity and pest infestation expressed by the different genotypes might have been due to their genetic potential. 4.Conclusion Based on the present study it can be concluded that the genotypes, Agg-Sel-1, Agg-Sel-3 Agg 1522, and Agg 1692 recorded higher yield compared to other genotypes and the genotypes, Agg 1528, Agg1532 and Agg-Sel-2 showed lesser disease incidence and pest infestation. Hence these genotypes showing better performance can be utilized for further breeding programmes. Declaration of competing interest The authors declare that they have no conflict of interest. Declaration of generative AI and AI-assisted technologies in the writing process. The authors declare that they have not used AI … Read more