Asian Journal of Agricultural and Horticultural Research

Phytohormonal Control and Crosstalk in Litchi Fruit Development, Ripening, Abscission and Quality Regulation

Garima Pathak — 2026-04-21

Litchi (Litchi chinensis Sonn.) is a commercially important non-climacteric fruit crop whose fruit development, maturation, abscission, and postharvest quality are carefully controlled by a complex network of phytohormones. Unlike climacteric fruits, litchi ripening is predominantly controlled by abscisic acid (ABA) and sugar signaling, with ethylene playing an important role in fruit abscission, senescence, and postharvest degradation. This chapter summarizes current knowledge of main hormone roles in litchi fruit physiology, including ethylene, ABA, jasmonates, brassinosteroids, and salicylic acid. Ethylene regulates abscission by activating cell wall-degrading enzymes and leads to pericarp browning and senescence when in storage. In contrast, ABA is a key regulator of fruit maturity, boosting anthocyanin accumulation, sugar transport, and ripening commencement. New research emphasizes the role of hormonal crosstalk, including auxin-ethylene antagonism, ABA-sugar synergy, and ABA-ethylene interaction, in influencing fruit retention, ripening process, and stress responses. Jasmonates, brassinosteroids, and salicylic acid improve stress tolerance, defense mechanisms, and postharvest quality.Despite these advancements, some crucial research gaps remain. The molecular basis of hormone signaling and crosstalk is still poorly known, especially in terms of gene regulatory networks and functional validation of important genes. Limited integration of multi-omics techniques limits our understanding of ripening and stress physiology. Furthermore, the effects of minor hormones are understudied, and hormonal control throughout postharvest stages, particularly the mechanisms behind pericarp browning, warrants greater exploration. There is also a dearth of standardized, cultivar-specific protocols for applying plant growth regulators (PGRs), as well as insufficient research on genotype-specific responses and the effects of climatic change on hormonal balance. Bridging the gap between laboratory research and field-based applications remains a significant problem.Future research that incorporates modern multi-omics technologies, precise hormonal manipulation, and climate-resilient tactics will be critical for increasing productivity, improving fruit quality, and assuring sustainable litchi farming.

Influence Interaction of Zinc Mineral and Chelate at Different Levels of Potassium Fertillizer in Some Zinc Nutrient Use Efficiency Indices for Wheat Crop Grown in Gypsiferous Soil

Ahmed Ibrahim Khalaf Albajary — 2026-03-19

Potassium is a fast-moving element within plants and plays an influential role in regulating and arranging the osmotic pressure within the cell, as well as working to balance the cations and anions in the cell cytoplasm. A field experiment was carried out in Salah al-Din Governorat, to study the effect interaction of zinc from two sources, chelated and mineral, at different potassium levels on wheat indices. The experiment was designed according to (RCBD) and included two factors: the first factor Zinc fertilizer (chelate, mineral) at three levels for each it is (stander) for both, zinc mineral (10, 20) Kg h^-1, zinc chelate (10 ,20) Kg h^-1 and the second factor is potassium sulphate (K₂SO₄) at levels (0, 80, 160 ,240) Kg h^-1. The results showed the highest value interaction of physiological efficiency (PE) was obtained from the combination of (Zn₄ K₂) and significantly different from other treatment which reached an average of (15926.70) Kg Kg^-1 while the treatment (10Zn chelate Kg ha^-1 + 160 K Kg h^-1) gave the highest value for the Agronomic efficiency (AE) trait which significantly outperformed the rest of the traits within the same potassium fertilizer level as it reached (135.5) Kg Kg^-1, The treatment (Zn₃ K₃) also gave the highest rate of Apparent recovery efficiency (ARE) which was significantly superior, reaching (1.93 ) % , As for the Utilization Efficiency (UE) it reached the highest value (28656.4) ) Kg Kg^-1 which was recorded by the treatment (Zn₃ K₂).

Effect of NPK Fertilizer and Plant Density on the Growth and Yield of Eggplant Crop (Solanum melongena) in Sandy Soil

Habeeb A. Yahya — 2026-03-24

The eggplant plant (Solanum melongena L.) is the annual vegetable grown in the warm regions and consider one of the important vegetable crops in the world, due to the highly nutritive values, and medicinally benefits. One of the strategies to enhance production is through the improvement of cultivation techniques. The Research was conducted at the Nursery of Department of Crop Science, Faculty of Natural Resources and Environmental Studies, University of Kordofan. Elobeid, Sudan. The aim of this research is to determine the effect of NPK fertilizer and plant density and to find the best dose and density on the growth and yield of eggplant. Six treatments in two seasons were used: 1 plant 0g of NPK, 2 plants 0g of NPK, 1 plant 5g of NPK, 2 plant 5 g of NPK, 1 plants 10 g of NPK, 2 plants 10g of NPK. The treatments were arranged in a Randomized Complete Block Design (RCBD) with four replicates. Parameters studied included number of leaves/plant, leaf length (cm), Leaf width (cm), stem length (cm) Number of branches/plant, Number of flowers/plant, fruit length (cm), fruit width (cm), and fruits yield (ton/feddan). In the first and second season the statistical analysis of the data showed significant differences between the treatments on the number of leaves per plant, leaf length, leaf width, stem length, number of branches per plant, number of flowers per plant, fruit length, fruit width, and fruits yield. The treatment 2pt 10g NPK had highest values of number of leaves/ plant (84 and 79), fruits length(20.8 and 22.18cm), fruit width (9.5 and 7.79 cm), fruits yield (9 and 34 ton/ha) while the lowest values (10 and 21), (10.2 and 15.67 cm) , (4.5 and 4.02 cm), (4 and 17 ton/ha) where obtained in the treatment 1 pt 0g NPK in 2023 and 2025 respectively, the results showed that the application dose of 10g of NPK and density 2plant/hole gives good and effective results compared to a dose of 5g NPK either with one or two plant.

In Vitro Propagation and Rooting Ability of Wild Plum Genotypes (Prunus cerasifera Ehrh.)

Hürü Altan — 2026-03-26

In this study, the propagation and rooting ability of wild plum (Prunus cerasifera Ehrh.) genotypes collected through selection was tested under in vitro conditions. During the propagation phase, 4 different BAP doses (0.5, 1.0, 1.5, 2.0 mg/L^-1) were applied to shoots from 6 genotypes (nos. 4, 9, 33, 42, 47, 49), while 5 different IBA doses (0.5, 1.0, 1.5, 2.0, 2.5 mg/L^-1) were applied during the rooting phase. During the experiment, measurements were taken of the average shoot number, shoot length, leaf number, average root number, number of rooted plants, and root length for each genotype. As a result of the analyses, while the shoot length remained short at the doses with the highest shoot count, the highest shoot length was recorded at the 2 mg/L^-1dose, where the shoot count decreased, for genotype 47 (4.97 cm). The average shoot number was 2, and genotype 49 was found to have the lowest shoot number in the 2 mg/L^-1BAP medium. Genotype 47 reached the highest plant number 100, in the 1 mg/L^-1BAP medium at the end of the third subculture. Again, in the 2 mg/L^-1BAP medium, genotype 47 stood out with a shoot length of 4.97 cm and a leaf count of 16. The best rooting percentage was obtained in genotype 42 at a 2.0 mg/L^-1IBA dose (88.71%) and in genotype 4 at a 1.5 mg/L^-1 dose of 1.5 mg/L^-1 (84.00%). Based on the general averages, the most effective IBA dose was 1.5 mg and 2 mg/L^-1), with the highest rooting rate calculated at 68%. The 2.5 mg/L^-1 IBA dose produced the highest number of roots and root length. The study showed that tissue culture protocols cannot be uniform and that genotypes respond differently to hormone doses. The P. cerasifera type of plum is an important species due to its strong adaptability, its cultivation being more economical than other species, its high tolerance to biotic and abiotic environmental conditions, and its preference as a rootstock. Detailed examination of these genotypes is required. It is important in terms of introducing new materials to breeding studies and conserving genetic resources.

Impact of Auxin Rates on Vegetative Growth and Nutrient Uptake of Ornamental Palm Varieties in Ogbomoso, Southwestern Nigeria

O. F. Sadiq — 2026-03-30

Ornamental palms are valued for their aesthetic appeal and landscape versatility, contributing significantly to urban greenery and nursery based horticultural enterprises. Despite their economic and ecological importance, vegetative growth and nutrient efficiency in palms are often constrained by suboptimal management practices, including inadequate use of plant growth regulators. This study evaluated the effects of different auxin growth hormone rates on vegetative growth and nutrient uptake of selected ornamental palm varieties in southwestern Nigeria. The experiment was conducted in a screen house at the Teaching and Research Farm, Ladoke Akintola University of Technology (LAUTECH), Ogbomoso. Factors considered were Three ornamental palm varieties (Queen palm, Golden palm, and Fan palm) subjected to five auxin rates (0, 0.2, 0.4, 0.6, and 0.8 ml/L) in a 3 by 5 factorial arrangement using a completely randomized design with six repetitions. Data on plant height, number of leaves, stem girth, and nutrient uptake were collected and analyzed using ANOVA and treatment means separated by least significance difference at 5% probability level. Results showed that auxin rates, variety, and their interactions significantly (p ≤ 0.05) influenced all measured growth parameters and nutrient uptake. The 0.6 ml/L auxin rate consistently produced superior vegetative growth, while 0.8 ml/L enhanced nitrogen and potassium uptake. Among the varieties, Queen palm exhibited the greatest overall height and leaf production, whereas Golden palm recorded the highest stem girth and nutrient assimilation efficiency. Significant interaction effects indicated that varietal responses were strongly dependent on hormone concentration and plant age. The study demonstrates that auxin application at 0.6 ml/L, enhances vegetative growth and nutrient uptake of ornamental palms, with Golden and Queen palms showing superior performance.

Modulating Morphological Architecture: The Role of Paclobutrazol in Inducing Compactness and Pseudobulb Expansion in Dendrobium Orchids

W. M. D. N. Warigajeshta — 2026-04-09

Aims: To evaluate best concentration of Paclobutrazol (PBZ), a gibberellin biosynthesis inhibitor, on the growth and flowering characteristics of Dendrobium ‘TC 32’ to achieve a compact, sturdy growth habit suitable for commercial pot plant production.

Study Design: The experiment utilized a Randomized Complete Block Design (RCBD). It was conducted under glasshouse conditions with 70% shade at the Floriculture Research and Development Unit (FRDU), Department of National Botanic Gardens, Peradeniya, Sri Lanka.

Methodology: Two-year-old, sixty tissue-cultured plants (average height 23.25 cm) were treated with four concentrations of PBZ: 0.0 (control), 0.2, 0.4, and 0.6 mg/L (T1–T4). Growth parameters (tiller height, pseudobulb circumference, leaf production and tiller production) were monitored from November 2023 to October 2025. Floral quality (flower count and spike height) was recorded bi-weekly following spike initiation in May 2024.

Results: Higher concentrations of PBZ significantly influenced plant architecture (P < 0.001). Height: T4 (0.6 mg/L) resulted in the shortest plants, with a mean tiller height of 9.37± 1.50 cm (F=163.78, P<0.001) and a mean spike height of 8.9 ± 1.03 cm (F=648.74, P<0.001. PBZ treatment significantly increased pseudobulb circumference 8.93 ± 0.96 cm (F= 32.89, p< 0.001). There was no significant effect on the total number of flowers 9.33±1.23, (F=1.04, P=0.381), tiller count 3.93 ± 0.80 (F=2.40, P= 0.077) or leaves produced 6.60±1.06, (F=0.46, P=0.71). (P>0.05)

Conclusion: Paclobutrazol effectively induces dwarfism and increases pseudobulb robustness in Dendrobium orchids. To balance growth retardation with overall plant vigor, T2 (0.2 mg/L) is recommended as the most suitable concentration for producing high-quality, compact flowering Dendrobium ‘TC 32’ under local glasshouse conditions in Sri Lanka.

Effect of Branch Pruning on Earliness and Fruit Quality in Tomato (Lycopersicon esculentum Mill)

Oyewole, Charles Iledun — 2026-04-13

Different pruning techniques can be employed to optimize earliness and fruit size, including sucker removal and lateral branch pruning, with pruning usually practiced by farmers to enhance quality and increase yield of tomato crops. The experiment was conducted at the Faculty of Agriculture, Students’ Research and Demonstration Farm, Prince Abubakar Audu University, Anyigba, located at latitude 7° 30′N and longitude of 7° 09′E, within the Southern Guinea Savannah agro-ecological zone of Nigeria. The trial, a Randomized Complete Block Design (RCBD) consisted of a variety of tomato (Roma VF) apportioned to three pruning regimes (0, 50 and 100 %), with all treatments replicated five times. Seeds of Roma VF were raised in the nursery for 35 days to attain 4 – 5 leaf stage before transplanted into experimental pots, measuring 15 cm by 30 cm. regular watering were carried out using hand held sprayer, while hand weeding ensure a weed free environment. NPK 20:10:10 fertilizer was sparingly applied at 2WAT (Week after Transplant). Data were collected on days to flowering, first harvest, fruit weight, length and diameter. Generally, pruning accelerated earliness, with the earliest harvest observed in 100% branch pruning, while the longest average numbers of days to first harvest were observed where the tomato stands were not pruned. The highest numbers of fruits were obtained when the tomatoes were not pruned, but fruits were generally smaller, compared with other treatments. For best Practice 50% pruning is recommended as it improves earliness and fruit quality without drastically reducing yield and if market demands value larger fruits, pruning is beneficial, however, if total yield is more important, no pruning is preferred.

Determinants of Farmers’ Perception and Adoption of Integrated Pest Management in Vegetable Production: Evidence from Kavrepalanchok District, Nepal

Lekh Raj Dhakal — 2026-04-17

The high use of agricultural chemicals, a hallmark of the green revolution, initially increased food production but has proven unsustainable, with adverse impacts on ecosystems, the environment, and human, animal, and plant health. This has led to the search for integrated measures for plant protection, such as Integrated Pest Management (IPM). Although the net consumption of chemical pesticides in Nepal is relatively low (0.396 a.i. kg/ha) compared to developed countries, careless, unsystematic, and unnecessary use has created a significant chemical pesticide hazard, demanding an expansion of IPM practices. This study, conducted in the vegetable-growing area of Kavrepalanchok district, focused on farmers' perceptions and the economic differences resulting from IPM practices. A survey was administered to 241 vegetable growers, divided into IPM and non-IPM adopters. Data were analyzed using descriptive statistics, t-tests, and a logit regression model. The results revealed a higher benefit-cost ratio for IPM practices compared to non-IPM practices. Factors such as training, livestock holding (LSU), membership in farmer groups, credit availability, government support, education level of the household head, and access to marketing and other agricultural information were found to significantly affect IPM adoption. Conversely, family size, age of the household head, and land-holding size were not found to be significant factors in the adoption of IPM practices. The findings suggest that institutional development, including market management for IPM products, certification, and the commercial production and availability of biopesticides and other eco-friendly tools, is essential for promoting the wider adoption of IPM.

Smallholder Farmers' Participation in the Agricultural Market Systems in Rangpur District, Bangladesh: Challenges and Opportunities

Md. Ashraful Islam — 2026-04-23

This study examines the demographic characteristics, production patterns, post-harvest practices, market participation, income outcomes, challenges, and opportunities within agricultural market systems for livelihood diversification among smallholder farmers in Rangpur district, Bangladesh. The study employed a mixed-methods approach, combining household surveys (n= 120), focus group discussions (n=6), and key informant interviews (n=9) with stakeholders and market actors. Findings were triangulated with secondary sources to ensure reliability. The results show notable variation in landholding size, with medium and large landholders comprising the majority, while agriculture remains the dominant source of household income. Rice is the principal crop, cultivated by 89.17% of farmers, alongside diversified vegetable production. Post-harvest practices are partially adopted, with many farmers conducting basic activities such as cleaning and sorting, but improved practices like packaging and pre-cooling remain limited. Most farmers depend primarily on local markets (69.17%), with limited access to wider regional or national markets. In addition, 62.50% of farmers rely on intermediaries (Paikers) to sell their produce, which often reduces their bargaining power and farm-gate prices. Farmers also face several market-related challenges, including weak collective marketing, price volatility, and limited storage and market information. Despite these constraints, the agricultural sector shows strong potential for growth. Despite these challenges, 84.17% report high demand for high-value crops, 80.00% have access to quality inputs, and 82.50% of youth and women participate. The findings emphasize that integrated market system approaches, improved post-harvest management, and promotion of collective marketing can enhance farmer income, strengthen livelihoods, and support sustainable agricultural development.