Journal of Tropical Crop Science Welcome to the online submission and editorial system of the Journal of Tropical Crop Science. The Journal of Tropical Crop Science (JTCS; p-ISSN: 2356-0169; e-ISSN: 2356-0177) is an open-access, international, peer-reviewed journal that publishes articles reporting research findings on in vivo and in vitro crop production and management under tropical conditions. Our open access policy allows immediate, free access to the articles and permits any user to read, download, copy, distribute, print, search, or link to the full texts of articles; crawl them for indexing; pass them as data to software; or use them for any other lawful purpose. The scope of the journal includes studies on crop production, breeding, seed technology, physiology, postharvest management, pests, and pathology of tropical cereals, vegetables, fruits, ornamentals, medicinal and plantation crops, soil, landscape, turf, and agroecological management. All articles are published under the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license. Under the terms of this license, authors retain copyright and grant the journal the right of first publication. Others are free to copy, redistribute, and remix the material in any medium or format. Users must give appropriate attribution/credit, link to the original, include the name, provide license info, and keep their derivative work under CC BY-SA. JTCS is published by the Department of Agronomy and Horticulture, IPB University, Indonesia. We accept submissions from researchers worldwide. Our Editorial Board members are prominent and active international researchers in agriculture, horticulture, and biosciences. All accepted articles will be published upon payment of an article-processing charge of IDR 2,500,000 and will be freely available to all readers worldwide. JTCS has been indexed/registered in SCOPUS as of 20 March 2024 (SJR rating in progress), ASCI (Asian Science Citation Index), AGRIS FAO, and WORLD CATALOGUE LIBRARY. Journal of Tropical Crop Science accepts the following types of papers Original research papers: report the results of original research. The material should not have been previously published elsewhere. Review articles: cover a part of the subject with an active current interest. They may be submitted or invited. Original research papers and review articles should have a maximum of 8,000 words, including figures and tables. Short Communications: report of preliminary research results, newly developed methodology or modification of existing methodology, and results of the application of an earlier published research methodology on other crops or under different conditions. Short communications should be as completely documented, both by reference to the literature and description of the experimental procedures employed, as a regular research paper with a maximum of 2000 words, with a maximum of three tables or figures, and up to 20 references. PRINTED ISSN: 2356-0169 ELECTRONIC ISSN: 2356-0177 The Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University JOURNALS: Jurnal Agronomi Indonesia Jurnal Hortikultura Indonesia Journal of Tropical Crop Science The Journal of Tropical Crop Science content is currently preserved in LOCKSS.
Department of Agronomy and Horticulture, IPB University
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Growth, Physiological, and Yield Responses of ‘Micro-Tom’ and Commercial Tomato Varieties Under High Temperature Conditions
Tomato, a nutrient-rich horticultural crop, is widely cultivated and consumed worldwide, with the ‘Micro-Tom’ cultivar commonly used as a model plant for its compact size and rapid life cycle. In tropical regions, rising temperatures caused by climate change intensify heat stress, which disrupts pollen viability and reduces fruit set, thereby limiting tomato productivity. This study aimed to evaluate the growth, physiology, and production responses of 'Micro-Tom' and three commercial tomato varieties 'Bareto' F1, 'Gustavi' F1, 'Tymoti' F1 under high temperature (HT) conditions. The experiment was conducted from March to November 2023 at the Leuwikopo Experimental Field, IPB Bogor, using a randomized complete block design with two factors (temperature and variety) and three replicates. For the HT treatment, plants were placed in a UV-protected plastic house, resulting in a minimum temperature of 18.7 °C and a maximum temperature of 46.2 °C. In contrast, the standard temperature (ST) treatment had a minimum temperature of 17 °C and a maximum temperature of 40.2 °C. The treatments lasted approximately three months, from transplanting to harvest. The standard temperature (ST) treatment outperformed the high-temperature (HT) treatment across all measured parameters, including plant height, leaf number, flower number, chlorophyll content, glucose and fructose levels, and fruit production. Among the varieties, ‘Bareto’ F1 exhibited superior performance across most parameters. Limitations of this study include its implementation in a controlled field setting over a single season. These findings highlight the need for further investigation into heat-tolerant genotypes and the physiological mechanisms that enhance tomato resilience under climate induced stress.
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Effect of Drought Stress on Chlorophyll Fluorescence and Yield Components of Common Beans (Phaseolus vulgaris L.)
The nutritional benefits of legumes to humans are surpassed only by those of the Gramineae family. The common bean (Phaseolus voulgaris L.) is one of the most widely cultivated legume crops and an important source of protein in South Korea. Among the major abiotic stresses affecting common bean production in South Korea, drought stress is the most significant. However, the most vulnerable stages of drought stress after planting are unknown. Therefore, this research has been conducted. The RWR2245 common bean variety was planted in a greenhouse after land preparation under a randomized complete block design (RCBD) with four replications. Three drought stress treatments were imposed during the growth period at 3, 6, and 9 weeks after planting (3 WAP, 6 WAP, and 9 WAP, respectively) by withholding water for 10 days, followed by a 1-week recovery period before data collection. The recorded data included plant height, leaf number, number of floral buds, shoot dry weight, lateral root number, primary root length, root nodule count, root dry weight, quantum photosynthetic yield, and maximum photochemical efficiency. These measurements were compared with those of the control treatment. The data were analyzed for variance (p < 0.05) using Minitab 2025 version 22 3.1 and Microsoft Excel. Except for the number of nodules, water stress significantly decreased for all measured parameters at 6 WAP, whereas at 9 WAP, only the number of leaves decreased significantly. Drought stress at 3 WAP resulted in significant decreases in all studied parameters except primary root length and leaf number. At 9 WAP, drought stress had no effect on the number of floral buds or pods; however, common bean plants were more tolerant to drought stress at 9 WAP. Further studies are needed to enhance common bean tolerance to drought stress across different growth stages to increase productivity, particularly at 6 WAP, which proved to be the most vulnerable stage.
Interactive Effects of Nano-Iron and Spent Mushroom Extract on Growth and Nutrient Uptake of Citrus trifoliata Rootstock Saplings
Citrus trifoliata rootstock production is critical for the successful establishment of citrus orchards because sapling vigor strongly influences orchard performance. An experiment was conducted under 50% shade to evaluate two factors: foliar application of nanoiron at three concentrations (0, 10, and 20 mg/L) and an organic amendment, spent mushroom extract (SME), applied via irrigation water at three concentrations (0, 50, and 100 ml/L), on the growth and nutrient status of C. trifoliata saplings. The combined treatment of nanoiron at 20 mg/L plus SME at 100 ml/L increased plant height by 130%, stem diameter by 180%, and branch number per plant by 350% over the control, along with concurrent increases in leaf area, chlorophyll content, and carbohydrate accumulation. Foliar application of nanoiron integrated with SME provides a long-lasting, sustainable nutrient source that markedly improves sapling health and growth. This integrated approach can be considered an effective and practical strategy for enhancing nursery management and supporting sustainable citrus production.
Optimizing Potassium Fertilization for Precision Nutrition: Effects on Growth, Physiology, and Seed Potassium Content of Two Soybean Varieties
Potassium is an essential macronutrient that supports major physiological processes in plants and strongly influences soybean productivity. This study aimed to evaluate the effects of different potassium fertilization levels on plant physiology, yield performance, and seed nutritional composition in two soybean varieties, ‘Dena 1’ and ‘Denasa 1’.The research employed a factorial completely randomized group design with five potassium fertilizer levels (0, 15, 30, 45, and 60 kg K2O/ha) and two soybean varieties (‘Dena 1’ and ‘Denasa 1’), with three replications. The results showed that the potassium dose significantly affected plant height and leaf number but did not influence photosynthetic rate or stomatal conductance. The ‘Dena 1’ variety exhibited better growth, greater leaf greenness, and faster generative development than ‘Denasa 1’. The optimal potassium dose of 45 kg/ha improved yield components, resulting in a 30.7% increase in seed weight and a 45.8% increase in the number of filled pods compared with the control. A positive correlation was found between plant potassium content and key physiological traits, such as photosynthesis and transpiration rates. Seed nutrition analysis showed that soybean varieties significantly influenced nitrogen and phosphorus levels at the R7 and R8 stages, whereas the potassium fertilization dose had no significant effect on seed nutrient concentrations. Nutrient levels increased from R6 to R7 before declining at R8, reflecting nutrient redistribution during seed filling. Overall, the results suggest that applying 45 kg K2 O/ha is an effective fertilization rate for enhancing soybean physiological performance and yield, while varietal characteristics remain the primary factor shaping seed nutritional composition.
Enhancing Flowering in Vanilla (Vanilla planifolia L.) 'Vania 1' Using Jakaba Fungi and Coconut Water
Flowering is a crucial phase in vanilla (Vanilla planifolia) cultivation, heavily influenced by environmental conditions and cultivation practices. This study investigates the combined effects of Jakaba fungi and coconut water, a natural source of plant hormones, on vanilla flowering. The experiment followed a completely randomized block design with 12 treatment combinations and three replications. Each treatment used two plants, with five untreated controls and five plants treated with farmer standard Jakaba application, for a total of 82 plants. Coconut water was applied at 50, 100, and 150 ml per plant, while Jakaba was used at 150, 200, and 250 ml per plant. The optimal combination—200 ml of Jakaba with 50 ml of coconut water—resulted in the highest flowering and fruiting response. These findings highlight the potential of integrating Jakaba and coconut water to boost vanilla productivity.
Assessing the Effect of Chromolaena odorata on Maize (Zea mays L.) Growth and Yield in the Semi-Deciduous Forest Zone of Côte d’Ivoire
Chromolaena odorata is a dominant pioneer species in the successional vegetation following deforestation in humid and sub-humid tropical regions. Despite its prevalence, the specific interactions between C. odorata and subsequent food crops remain poorly characterized. This study aimed to evaluate the influence of C. odorata on the growth and yield of maize (Zea mays L.) under varying nutrient regimes. The experiment employed a randomized complete block design to assess the interaction between shrub presence (present vs. absent) and fertilization (0 or 1× the recommended N–P–K rate). The results indicated that the presence of C. odorata significantly increased maize height, stem diameter, and leaf count after anthesis. Furthermore, under high-rainfall conditions, C. odorata significantly increased grain yield and yield components. During the long rainy season, grain yields ranged from 8.75 to 10.74 ton/ha in plots integrated with C. odorata, compared to 7.63 to 7.84 ton/ha in monoculture plots. These agronomic advantages suggest that C. odorata improves productivity through non-thermal biomass management, likely by stabilizing soil pH. Notably, total nitrogen, available phosphorus, cation exchange capacity (CEC), and organic carbon content remained stable across the 0–20 cm and 20–40 cm soil profiles.
Growth Performance and Yield of Lettuce (Lactuca sativa L.) on Different Media in an NFT Hydroponic System
The operational success of closed-loop hydroponic systems is largely governed by the synergistic selection of the cultivation substrate and crop variety. An optimal growing medium must provide reliable structural stability, uniform moisture retention, and localized nutrient accessibility, which, when coupled with a cultivar’s inherent genetic potential, dictate overall vegetative development and marketable yield. This study evaluated the effects of different growing media and lettuce cultivars on growth dynamics and yield performance in a nutrient film technique (NFT) system. The experiment was arranged in a two-factor completely randomized design, evaluating lettuce cultivars ‘Arroyo’, ‘Amaroza’, and ‘Espirando’ and growing substrates: rockwool, cocopeat, and peatmoss. The results revealed significant interaction effects between cultivar and growing media for plant height at 28 days after transplanting (DAT) and rosette canopy diameter at 7 DAT. The treatment combination integrating the cultivar ‘Arroyo’ with a peat moss substrate consistently yielded the highest values for these growth parameters. Furthermore, across all evaluated growing media, ‘Arroyo’ demonstrated superior biomass accumulation and overall productivity, highlighting its robust agronomic suitability for tropical NFT hydroponic cultivation.
Phenotypic Evaluation of Fe and Zn Content and Agronomic Traits in Sorghum Segregating Population
Biofortification is one approach to overcoming micronutrient deficiencies by enhancing the nutritional content of food crops. Biofortification of sorghum’s iron (Fe) and zinc (Zn) content is essential to increase sorghum’s value as an alternative carbohydrate source. This research aimed to study phenotypic variation in Fe and Zn content and its correlation with agronomic traits and yields in the F3 population generated from a cross between the ‘Demak 4’ and ‘Soper 6 Agritan’ developed using the Single Seed Descent (SSD) method. This research was conducted at the Muara Experimental Field in Bogor, from May to August 2024. The experiment used an augmented design with four replications based on an individual-based segregated design. Fe and Zn content in sorghum grain samples was measured using an X-ray fluorescence machine. The results showed that the Fe content in sorghum grain within the F3 population ranged from 11.70-21.80 ppm, and Zn content ranged from 16.70-26.25 ppm. The correlation analysis showed that Fe content was not related to agronomic traits or yield. Zn showed a significant positive correlation with flag leaf area (r = 0.30, p < 0.01) and stem diameter (r = 0.24, p < 0.05). Fe and Zn content of sorghum grain was observed to be positively correlated (r = 0.68, p < 0.001). The results of multi-character identification using MGIDI yielded 10 selected genotypes: G1, G2, G6, G18, G20, G63, G82, G108, G122, and G181. Genotypes G1, G2, G181, and G122 are suitable for high yield.
Reducing the Use of Diuron-Active Herbicides Using a Combination of Wood Vinegar from Lignocellulosic Waste in Pineapple Plantations
Pineapple waste, which is rich in lignocellulosic compounds, can be thermally converted into environmentally friendly bioherbicides. This study aimed to evaluate the potential of lignin-derived compounds from lignocellulosic waste as a bioherbicide and to identify an effective formulation for reducing the use of diuron-based herbicides in pineapple plantations. Pyrolysis was conducted at subcritical temperatures, and the resulting wood vinegar was analyzed by GC MS to identify phenolic compounds. Pyrolysis at 250–300 °C produced phenolic compounds accounting for 40.20% of the chromatogram area, while pyrolysis at 400–450 °C produced 49.61%. The efficacy test included several treatments: pyrolysis products from 400–450 °C at 5% and 10%, pyrolysis products from 250 350 °C at 5% and 10%, diuron herbicide at 0.5 g/L, combinations of herbicide with two selected pyrolysis products, and a standard diuron application as the control. The results showed that wood vinegar produced at 400–450 °C and applied at 10% could suppress seed bank germination, with an effectiveness comparable to that of diuron at 0.5 g/L. This wood vinegar formulation was then used in a second efficacy test under pineapple cultivation conditions to assess whether diuron use could be reduced when combined with wood vinegar. The results indicated that combining 70% herbicide with 10% wood vinegar suppressed weed growth to a level similar to the 100% herbicide standard treatment. This study may serve as a reference for reducing the use of synthetic herbicides in pineapple cultivation.
Diversity and Species Composition of Fruit Flies (Diptera: Tephritidae) in Keerom, Papua, Indonesia
Information on fruit flies is essential for integrated fruit fly control programs, whilst such information remains very limited in Papua. This study aims to determine the species diversity and abundance of fruit flies in agroecosystems (Yuwanain) and secondary forest ecosystems (Ubiyau) in Arso District, Keerom Regency. Sampling locations were determined using purposive sampling. Fruit fly samples were collected using plastic bottle traps baited with methyl eugenol. Observations were conducted during May and June 2025. Four species of fruit flies were found in Arso District: Bactrocera musae, B. umbrosa, B. fulvicauda, and B. dorsalis complex. All four species were found in the agroecosystem area in Yuwanain, whilst in the secondary forest in Ubiyau, only three species were found: B. musae, B. umbrosa, and B. fulvicauda. All species were pests except B. fulvicauda. The Shannon-Wiener species diversity index values for fruit flies in the agroecosystem (H’ = 0.7) and in the secondary forest (H’ = 0.4) were both categorized as low. The Simpson Dominance Index in Yuwanain was classified as moderate (D = 0.636), whilst in Ubiyau it was categorized as high (D = 0.800). In Yuwanain, B. musae was highly dominant (D = 0.617) with a total individual count of 3,080. The dominance of B. musae in Yuwanain was attributed to the abundance of its primary host plant, banana, in the agroecosystem. The evenness index in Yuwanain village was moderate (E = 0.521), whereas in Ubiyau it was low (E = 0.381), indicating that the distribution of individual numbers for each species was uneven in the Secondary Forest. Fruit fly abundance was higher in the agroecosystem of Yuwanain (3,921 individuals) than in the secondary forest of Ubiyau (2,272 individuals). This difference is likely due to the greater diversity of host plants in the Yuwanain agroecosystem, including banana, papaya, jackfruit, citrus, wax apple, breadfruit, and chili. In contrast, the secondary forest of Ubiyau contains fewer naturally occurring host plants, such as the native Papua banana and breadfruit. It can be concluded that the species composition and abundance of fruit flies at certain habitat types were determined by the diversity and abundance of host plants.
Effects of Pollination Technique on Agronomic and Physicochemical Characteristics of Date Palm (Phoenix dactylifera L.) Fruits in the Sudan Savannah Region of Nigeria
Pollination is critical for producing many crops, and both insect- and wind-based pollination systems are increasingly disrupted by bloom asynchrony, weather events, and the high demand for available insect pollinators. Artificial pollination systems can provide yield security even in poor pollination scenarios and have attracted attention over the past decade. In Nigeria, date farmers still practice the oldest and most traditional technique of pollination, where male spikelets are manually inserted into the female inflorescence. This ancestral practice has many setbacks, which led to searching for other means for improving date yield. The present study aims to compare the agronomic and biochemical characteristics of the date ‘Danshuwarin’ cultivar under different pollination methods. Three methods were tested: traditional pollination, pollen dusting, and pollen suspension. The results obtained showed the dusting technique to be the most effective and efficient, followed by conventional methods. In contrast, pollen suspension has the highest number of fruit sets (80.79%) and retention rate (67.42%), while yield is 5.3% with the lowest parthenocarpic fruits of <2%. The results provide baseline information to uncover different pollination techniques on other Nigerian date palm varieties grown in diverse agroecological zones.
The Identification of Potential Stress in Oil Palm Using Sentinel-2A Satellite Imagery Approach and Laboratory Tests
Oil palm (Elaeis guineensis Jacq.) is a valuable source of vegetable oil for various industries, such as food and cosmetics. Global climate change, driven by global warming, has the potential to shift climate conditions and trigger extreme events, such as prolonged droughts. Extreme climate phenomena will impact plant conditions, causing plants to become stressed. A study was conducted from June 3 to October 31, 2023, at the Oil Palm Education and Research Plantation of IPB University in Jonggol, Bogor, West Java. The study aimed to determine the Palm Oil Stress Index (POSI) to identify stress in oil palm plants. The identification process included analyzing Sentinel-2A satellite images, testing soil water availability, and measuring leaf proline content. The study utilized the Leaf Water Content Index (LWCI) and Enhanced Vegetation Index (EVI) values as models to determine the POSI from the satellite images. Furthermore, soil physics analysis and proline values from the 17th leaf sample were used to assess the plants’ water availability and stress levels. The satellite images showed signs of potential stress in October; observation blocks in October had a pF value of 4.2 between 14.93%-16.77% compared to the water content, which ranged from 13.79%-15.09% supported by decreased soil water levels and increased proline accumulation occurred in October a value of 0.0382-0.0391 mg/g, compared to June, which is 0.0143-0.0159 mg/g. All areas were healthy from June to August; however, potential stress, as indicated by POSI values, their formulation, and color changes, was present in September and October.
Morphological and Phenological Study of Flowers and Fruits of Wild-Type Raspberries (Rubus spp.)
Wild-type raspberries are part of forest succession and could be cultivated owing to their benefits and economic value. The development of cultivated plants depends on the quality of the genetic material used for propagation. Phenological studies are the first step in assessing the quality of genetic material and in determining the overall developmental process. This research aims to study the development and morphology of flowers, fruits, and seeds. This research was conducted at Cibodas Botanical Garden from September 2022 to March 2023. The experiment used wild-type raspberry species as a factor in a randomized complete block design. The results showed differences in the developmental phases and morphology of flowers, fruits, and seeds, as well as in stigma receptivity, among R. fraxinifolius, R. rosifolius, and R. ellipticus. Flowers take 11–15 days from initiation to anthesis, and the receptivity of the stigmas of the three species reaches a peak one day after anthesis in the morning. The fruit is ripe at 39–46 days after anthesis with a different color.
The Effect of Light Intensity and Watering Intervals on the Growth and Flowering of Pentas (Pentas lanceolata)
Pentas (Pentas lanceolata) is an African ornamental species widely cultivated in Indonesia for landscaping and potted plant production. However, the optimal combination of light intensity and watering interval for maximizing growth and flowering under potted conditions remains unclear. This study aimed to evaluate the interaction effects of light intensity and watering intervals on the growth and flowering of Pentas. The experiment was conducted from December 2024 to March 2025 in Sukun District, Malang, Indonesia (440 masl.), using a split-plot design with three replications. Light treatments consisted of full light (100% or ± 18,898 lux), moderate light (75% or ± 12,216 lux), and low light (50% or ± 6,122 lux), while watering intervals were applied every 3, 4, or 5 days. Data were analyzed using analysis of variance (ANOVA) followed by Tukey’s Honestly Significant Difference (HSD) test. The results showed that light availability and watering interval influenced plant growth and flowering, with responses differing between growth stages. Optimal vegetative growth, indicated by the highest shoot dry weight, was achieved under moderate light intensity (75%) combined with a 4-day watering interval. In contrast, the best flowering performance was observed under full light conditions (100%) with the same watering interval. Full light increased the chlorophyll index by 28.73% compared to low light intensity (Figure 3), while moderate light accelerated flower initiation by approximately 19 days (9.40%) (Figure 4). Although watering alone had a limited effect, its interaction with light availability was crucial in regulating overall plant performance. These findings indicate that stage-specific management of light and watering is essential for optimizing the growth and flowering of potted Pentas.
Combined Tall and Short Genotypes Performance of Multi-canopy Rice in Dry and Wet Planting Seasons
The productivity of existing rice varieties has plateaued, while the area of rice fields continues to decline and the population continues to grow. Efforts to develop higher-yielding rice varieties have been made, one of which is the development of the multi-canopy rice system. This study aimed to assess the agronomic performance of tall and short rice genotypes in a multi-canopy (MC) system across two planting seasons. This study evaluated 22 MC combinations and two monoculture checks (‘Inpari 32’ and ‘Ciherang’) using a randomized complete block design with 3 replications, across dry and wet seasons at IPB University’s Babakan station. The results of the study showed that a significant C×S interaction was found only for the number of filled grains (NFG) trait. A better performance is generally observed in the dry season. The best performing combination was D15 (IPB200-F-60 and IPB200-F-12), which produced the highest grain yield of 7.27 tons/ha, outperforming the check varieties. Total number of tillers (TNT), number of productive tillers (NPT), and number of filled grains (NFG) were positively and significantly correlated with yield. MGIDI analysis identified multi-canopy combinations D15, D6, D20, D19, D1, D12, and D9 as potential based on six traits. These combinations should be tested across a wider range of environments to further elucidate the effect of genotype-by-environment interaction.
Effect of Glyphosate and 2,4-D Herbicides and Bacterial Inoculation on Soil Properties, Growth, and Yield of Maize (Zea mays L.)
Weed-control using herbicides can inhibit weed growth but can also affect soil properties and soil microbial activity, ultimately impacting plant growth and productivity. A field experiment was carried out in Najaf Governorate within the Agricultural Research Station at the University of Kufa during the autumn season of 2024-2025 in a sandy-loam soil to study the effect of glyphosate and 2,4-D herbicides and bacterial inoculation on some soil characteristics, growth, and yield of yellow corn (Zea mays L.). The experiment was conducted using a randomized complete block design with two factors: herbicides at three concentrations (half the recommended, full recommendation, and double the recommended) and bacterial inoculation. The results showed that the interaction treatment between bacterial inoculation (A. chroococcum) and the use of glyphosate at the full recommended concentration, as well as the control treatment, achieved the highest values in the studied characteristics. The highest concentration of available nitrogen in the soil reached 35.67 mg N/kg soil, and available phosphorus reached 26.67 mg P/kg soil. In contrast, the degree of soil reaction remained within the appropriate limits for plant growth. The electrical conductivity decreased to 1.22 dS/m. Soil bacterial counts also increased to 37.00 × 10⁶ CFU/g dry soil, which was reflected in an improvement in total yield to 15.57 mg/ha.
Optimizing SCoT-PCR Parameters for Reproducible Genetic Diversity Analysis in Cassava, Rice, Maize, and Foxtail Millet
Technical optimization of PCR parameters is essential to ensure efficiency and accuracy in genetic analyses. The performance and reproducibility of Start Codon Targeted (SCoT) markers are strongly influenced by annealing temperature (Ta) and primer concentration. Raising Ta from 50 °C to 55 °C reduced both amplicon yield and reproducibility, whereas higher primer concentrations increased amplicon counts without substantially affecting reproducibility. Optimal amplification was achieved at Ta 50 °C with a primer concentration of 2.5 μM, where most primers produced high amplicon numbers with 100% reproducibility. Evaluation of 36 SCoT primers in foxtail millet identified 20 primers with full reproducibility, of which 10 were further tested across cassava, rice, and maize. Primer reproducibility varied among species, and only SCoT‑35 and SCoT-36 consistently achieved 100% reproducibility across all three crops. These results highlight that primer suitability is species‑dependent and emphasize the need for extensive primer screening in each plant species. Overall, optimizing Ta and primer concentrations, combined with careful primer selection, is essential for the reliable, efficient, and cost-effective application of SCoT markers in plant genetic diversity analysis.
Characterization of Doubled Haploid Eggplant (Solanum melongena L.) Lines Obtained from Anther Culture
Eggplant (Solanum melongena L.) is an important horticultural crop widely cultivated worldwide. Stable genetic material and comprehensive information on genetic variability are essential for the development of superior varieties. Previous studies have obtained genetically stable doubled-haploid (DH) lines through anther culture. However, their agronomic performance has not been well identified. Therefore, this study aims to characterize doubled haploid (DH) eggplant lines (Solanum melongena L.) and identify potential candidates for future use as parental lines in hybrid breeding programs. Eleven doubled-haploid lines and three commercial varieties were evaluated using a randomized complete block design. Quantitative data were analyzed using analysis of variance (ANOVA), followed by Tukey’s HSD test at a 5% significance level, and cluster analysis based on phenotypic similarity. The results revealed significant variability among the genotypes for all quantitative characters except days to final harvest. Cluster analysis classified the genotypes into two major groups. Among the evaluated genotypes, Pro-AM1, Pro-AM38, Pro- AM50, and Hit-AM30 exhibited superior yield-related characters and are considered promising parental lines for hybrid development in eggplant. These findings demonstrate substantial genetic variability among the double-haploid eggplant lines and provide valuable resources for selecting superior lines to support future hybrid development.
Yield Components Response in ‘Barhi’ Dates Phoenix dactylifera to Organic Fertilization, Foliar Gibberellin, and Tryptophan
A two-season was conducted in the palm tissue culture station of orchard/horticulture department in Najaf Governorate, Iraq, from February 1st to October 1st 2024 for the first season and from February 1st to October 1st 2025 for the second season. The organic fertilization (sheep manure) at 0, 15, and 20 kg per tree, foliar spray with gibberellin at 0, 200, and 300 mg/L, and tryptophan at 0, 50, and 100 mg/L, were evaluated for their effects on ‘Barhi’ date palm growth and yield indicators. The results indicated that organic fertilization produced the greatest increase in leaf auxin and gibberellin content. In contrast, treatments with gibberellin and tryptophan resulted in comparatively smaller increases. Hormone levels in the control were approximately 20% lower than those observed in the lowest treatment. The fruit size was larger in the total interactions, but was not significantly affected by the individual treatment. However, fruit weight and cluster weight differed among the experimental factors. In general, the interaction treatment of organic fertilizer 20 kg per palm and gibberellins 300 mg/L in the presence of tryptophan 100 mg/L significantly resulted in the highest plant content of auxins (34.911 μg/g FW) and gibberellins (35.181 and 35.173 μg/g FW), fruit weight (13.020 and 11.573 g), fruit size (11.670 and 11.720 cm³), cluster weight (9.527 and 10.873 kg) and the total yield (38.109 and 38.780 kg per tree).
Study of Salinity Tolerance in Several Mutant Rice Lines Using Morphophysiological and Biochemical Approaches
Salinity is a major limitation to rice production. ‘Atomita 2’, a mutation-derived rice variety released in 1983, was originally reported to be salinity-tolerant, but detailed evidence of its tolerance remains limited. This study aimed to identify salinity-tolerant mutant lines of ‘Atomita 2’ and to characterize their morphological, physiological, and biochemical responses in the M4 generation under salt stress. The experiment was conducted in a greenhouse through two stages: initial screening of mutant lines under 60 mM NaCl and subsequent evaluation of selected genotypes for morphophysiological and biochemical traits. Screening identified 38 surviving genotypes. Salinity stress reduced plant height, tiller number, 100-grain weight, and grain yield, and decreased photosynthetic rate, stomatal conductance, transpiration rate, and SPAD value. In contrast, APX and CAT activities, proline, and MDA increased with NaCl concentration, indicating stress adaptation. ‘Atomita 90’ and ‘Atomita 146’ showed greater tolerance than ‘Atomita 2’ and ‘Pokkali’, as indicated by stress tolerance index values and their physiological and biochemical responses.
Molecular Identification Confirms Different Species of Cotton Jassids (Hemiptera: Cicadellidae) in Tanzania
Cotton (Gossypium hirsutum L.) is a strategic cash crop in Tanzania, supporting the livelihoods of approximately two million people and contributing substantially to the national agricultural economy through lint production and the textile industry. However, cotton productivity is severely constrained by sap-sucking insect pests, particularly cotton jassids (Hemiptera: Cicadellidae), which can cause yield losses of up to 50%. Pest management strategies have largely been implemented with limited knowledge of the actual species composition of jassids infesting cotton fields. This study aimed to establish the molecular identity of cotton-associated sucking pests, with an emphasis on jassids, in major cotton-growing areas of Tanzania. A total of 25 specimens were collected from cotton fields in Bunda, Meatu, Misungwi, and Kilosa districts. Genomic DNA was extracted using the Quick- DNA™ Mini Prep Plus Kit, and the mitochondrial cytochrome oxidase subunit I (COI) gene was amplified using COI 1-3b and COI 2-4b primer pairs. PCR amplicons were visualized on 1.2% agarose gels, and successfully amplified products were sequenced. Approximately 650-bp COI sequences were analyzed using Maximum Likelihood methods implemented in MEGA v.12 and aligned with global reference datasets to infer phylogenetic relationships. Phylogenetic reconstruction resolved well-supported clades representing Amrasca, Jacobiasca, Ghauriana, and Empoasca species. Most specimens clustered strongly with authenticated reference sequences of Amrasca biguttula (bootstrap support 92–100%), confirming its presence as a dominant cotton pest. Additional samples grouped with Jacobiasca lybica, Jacobiasca formosana, Ghauriana sinensis, Empoasca distinguenda, and E. flavescens. Findings reveal considerable species diversity among cotton jassids in Tanzania and underscore the importance of integrating molecular diagnostics into routine pest surveillance to support species-specific and sustainable integrated pest management strategies.
Spatial Analysis of Viral Outbreaks in Indonesian Tomato Cultivation: Pathways to Sustainable Farming
Tomato production in Indonesia is severely threatened by viral pathogens, compromising yield and food security. This study analyzed the spatial distribution of viral infections in 483 tomato samples collected from 11 provinces spanning 38 districts. Using RT-PCR and PCR diagnostics, we detected an overall infection rate of 96%, encompassing both RNA and DNA viruses. Pepper yellow leaf curl Indonesia virus (PepYLCIV) was the predominant DNA virus, while cucumber mosaic virus (CMV), tobacco mosaic virus (TMV), and tomato mosaic virus (ToMV) were the most widespread RNA viruses, frequently co-infecting with DNA viruses. Mixed infections were common, with up to five viruses detected in single samples, reflecting high viral complexity and crop vulnerability. An inverse relationship between infection complexity and crop vulnerability. An inverse relationship between infection complexity and incidence rate was observed: samples containing more viruses occurred less frequently. The variability of symptoms between single and mixed infections further hinders accurate visual diagnosis, underscoring the need for molecular detection tools. Spatial analysis revealed that Java Island had the highest incidence of viruses and the greatest diversity of combinations. Notably, North Sumatera (Tanah Karo), East Kalimantan (Samarinda and Balikpapan), and Central Sulawesi (Palu, Donggala, and Sigi) also exhibited high virus incidence and frequent DNA–RNA virus coinfections.
Effect of Mint and Rosemary Aromatic Oil Extracts on the Mortality of the Stored Date Pest Ephestia cautella (Walker)
Ephestia cautella is one of the most common insect pests of stored dates, causing quantitative and qualitative losses. Therefore, this research aimed to evaluate the insecticidal effect of oil extracts from peppermint (Mentha piperita) and rosemary (Rosmarinus officinalis) against different larval instars of the date moth under laboratory conditions, to promote botanicals as a safe and environmentally friendly alternative for managing insect pests. This study was conducted in the Advanced Laboratory of Entomology at the Faculty of Education for Women, University of Kufa, during 2024-2025. The academic year showed the contact and digestive effects of both oil extracts at concentrations of 2.5%, 5%, 7.5%, and 10% on the mortality of second- and fourth instar larvae of E. cautella. The results showed high efficacy of the tested plant oil extracts in causing mortality across both larval instars. The contact effect of mint extract was slightly more effective against second-instar larvae than fourth-instar larvae across all treatments, with mortality reaching 100% in most treatments and concentrations, except at 2.5%, where it recorded 80% mortality for second-instar larvae. With rosemary extract, mortality percentages among fourth-instar larvae were higher under contact than under digestive treatment at all concentrations. Most contact treatments achieved 100% mortality, even at the 10% concentration. Digestive treatments resulted in an 80% mortality rate of second-instar larvae and a 50% mortality rate of fourth-instar larvae. These results demonstrate the potential of peppermint and rosemary oil extracts as effective botanical insecticides for controlling the date moth.