Tamil Nadu Horticulture University

Climate change poses significant challenges to global agriculture, particularly to horticulture, which is highly sensitive to climatic variations. Rising temperatures, changed precipitation patterns, and an increase in the frequency of extreme weather events highlight how urgent it is to implement climate-smart techniques since they all represent serious risks to conventional horticulture systems. Horticultural crops—fruits, vegetables, spices, ornamentals, and plantation crops—are uniquely vulnerable to climate change because quality traits and reproductive success are exquisitely sensitive to heat waves, droughts, salinity, flooding, and compound extremes. This review synthesizes recent advances (primarily 2021–2025) in the physiology and molecular biology of stress perception, signalling, and acclimation in horticultural species, with emphasis on traits that safeguard yield and quality. We summarise progress in understanding combinatorial stress responses, integrative hormone crosstalk, ROS–Ca²⁺ signalling, osmotic regulation, and source–sink balance under heat and water deficits. We then examine emerging levers for adaptation: epigenetic and priming-based memory, microbiome mediation, and organ-specific mechanisms in flowers, fruits, and storage tissues. A second focus covers practical strategies—from climate-smart rootstocks and grafting, CRISPR-enabled breeding, seed/foliar priming (e.g., melatonin, seaweed biostimulants), silicon nutrition, to protected cultivation and digital phenotyping—highlighting trade-offs and translational pathways. We close by outlining evidence gaps, research priorities, and policy-relevant directions to accelerate climate resilience in high-value horticulture.

The study aimed to examine the genetic variability and relatedness among 23 genotypes of athalakkai (Momordica cymbalaria Hook F.) evaluated at the college orchard, Department of Horticulture, Agricultural College and Research Institute, Madurai, Tamil Nadu. The study assessed yield-related traits such as days to sprouting, vine length, number of vines per plant, fruit stalk length, number of fruits per vine, number of fruits per plant, fruit length, fruit girth, fruit weight, number of seeds and yield per plant. Results showed significant variations in the mean performance of 23 athalakkai genotypes for various traits, indicating substantial genetic diversity and high breeding potential within the germplasm. The study of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) in M. cymbalaria germplasms showed variability in traits such as fruits per vine, number of seeds, number of fruits per vine, number of vines per plant, vine length and yield per plant. High heritability estimates and genetic advance were observed, indicating that variation is due to a high degree of additive effect and can be improved through selection. Correlation and path analysis results showed that vine length, number of seeds, number of fruits per plant, number of fruits per vine, fruit weight and fruit stalk length had a significant positive direct effect on the number of fruits per plant, suggesting these traits could be considered for yield improvement programs in M. cymbalaria.

Banana cultivation is increasingly challenged by limited land availability, climate variability, and declining resource-use efficiency, necessitating the adoption of precision-based production strategies. This review critically synthesizes recent advances in high-density planting (HDP), precision nutrient and water management, improved planting material, and other hi-tech interventions for enhancing banana productivity and sustainability. Evidence from experimental and multi-location studies indicates that HDP systems with plant densities ranging from 2,500 to 5,000 plants ha⁻¹ can increase yield by 19–79% over conventional planting, depending on cultivar, spacing, and management practices. Precision fertigation under HDP has been reported to reduce fertilizer use by 25–50% while maintaining or improving bunch weight, fruit quality, and economic returns. In addition, optimized planting geometry and resource management improve light interception, water-use efficiency, and overall system resilience. These approaches improve resource-use efficiency by reducing fertilizer and water inputs by approximately 25–50%, while enhancing economic returns through yield gains of 20–70% compared with conventional banana cultivation systems. This review highlights that integrating precision approaches with cultivar-specific recommendations offers a viable pathway for achieving sustainable productivity in banana cultivation, particularly under Indian and South Asian production systems, while also identifying key research gaps for future refinement. Graphical Abstract

This study aims to investigate the historical (1951–2024) and future projected (2026–2099) climate trends and change points in the Vellar River Basin under Shared Socioeconomic Pathways (SSP) using time series observations and downscaled Global Climate Model (GCM). Trends of rainfall and temperature were assessed based on the Mann–Kendall test. The change points detection were carried using Pettitt’s test, Standard Normal Homogeneity test, Buishand's range test and Von Neuman ratio test. The results revealed that historical rainfall found a declining trend seasonally as well as annually, with significant change points at 1979, 1981, and 1988. Future projections showed decreasing trend in rainfall, with notable change points at 2058, 2067, and 2084. The station Virudhachalam during Kharif, Vazhapadi and Karumandurai during Rabi and Annual period recorded more significant decreasing trend. The result of historical and future temperature projection displayed a significant upward trend. The historical minimum and maximum temperatures increased from 0.44 °C to 0.88 °C and 1.11 °C to 1.7 °C, respectively with change points for minimum temperature at 1996 and maximum temperature at 1979. The future predicts of temperature recorded an increasing trend of 1.5 °C, 2.0 °C, and 3.0 °C for maximum temperatures and 0.9 °C, 1.2 °C, and 1.5 °C for minimum temperatures under SSP 2.6, SSP 4.5, and SSP 8.5 scenario, respectively. Change points in maximum temperature are expected in the 2050s and 2060 for SSP 2.6 and SSP 4.5. Whereas SSP 8.5 anticipates at later 2080s, indicating a two-stage warming pattern with an early gradual increase followed by rapid rise towards the end of the century. These findings concluded by recommending the policy makers to develop climate adaptation strategies for agricultural and water management to mitigate the potential impacts of future climate condition.

Aims: Genetic divergence plays a crucial part in determining the selection of genotypes for any breeding programme in order to generate superior segregants. Assessing the local or related genotypes for divergence, imposses a necessity to conduct experiments on specific agro-ecological situations to breed specific varieties suitable for vegetable and gum purpose. Study Design: Randomized Block Design Place and Duration of Study: An elaborate study was performed in January to April 2022 at the field in Poothurai village of Villupuram District, Tamil Nadu to evaluate and screen the cluster bean germplasms. Methodology: A total of 102 genotypes (including Pusa Navbahar - a check variety) procured from various regions of the country were utilized. Observations were recorded for growth attributes (plant height; number of branches per plant; days to maturity), flowering and pod characters (days to 50 % flowering; number of clusters per plant; number of pods per cluster; pod length; pod girth), yield parameters (pod weight; number of pods per plant; total pod yield per plant), seed characters (number of seeds per pod; hundred seed weight; total seed yield per plant) and physiological components (guar gum; protein and fibre) on five randomly selected plants. Results: It divulged a paramount of diversity with the genotypes being grouped into 14 clusters based on 17 parameters. Seven clusters had more than 2 genotypes, and the remaining were solitary. Yield parameters such as total per plant yield (22.20%), pods per cluster (15.30%), and clusters per plant (14.80%) contributed to the highest percentage diversity. The distance between intra clusters ranges from 0.00 to 2031.87. The maximum distance between clusters observed is between cluster V and cluster IX (15980.81). Conclusion: Of the 102 genotypes, Cluster XIV having the sole member Pusa Navbahar performed better for six out of seventeen parameters observed for the mean of clusters. With respect to the above results obtained and per se performance of the landraces, selection can be made to obtain superior cluster bean recombinants.

Fruit flies pose a significant threat to ber (Ziziphus mauritiana Lamk.) cultivation, necessitating effective monitoring and management strategies. This study evaluated the efficacy of various attractants in trapping Carpomya vesuviana and Bactrocera correcta. Various baits were tested, including ripe pulp of ber, guava and banana; fish meal; jaggery solution; honey solution; ammonium acetate; proteinex and commercial lures (methyl eugenol and cue lure). However, no adults of C. vesuviana were captured. But B. correcta was effectively trapped, with methyl eugenol (T9) and cue lure (T10) consistently demonstrating superior efficacy across all standard weeks. These traps captured the highest mean number of fruit flies (54.6 and 49.5 flies/trap respectively), followed by proteinex (T8) (13.3 flies/trap) and guava pulp (T3) (7.4 flies/trap). Banana pulp (T2), fish meal trap (T4) and ammonium acetate (T7) showed moderate attraction, with mean trap catches of 6.2, 5.1 and 5.4 flies/trap respectively. In contrast, ripened ber fruit pulp (T1) showed limited effectiveness, with a mean trap catch of 4.8 fruit flies/trap. Honey solution (T6) and jaggery (T5) recorded the lowest trap catches, with mean values of 1.4 and 1.1 fruit flies/trap respectively, indicating minimal attractiveness. The findings confirm the efficacy of methyl eugenol and cue lure traps in attracting B. correcta, reinforcing their role in integrated pest management strategies. However, the failure to trap C. vesuviana highlights the need for alternative attractants tailored to its behavioural ecology. Future research should focus on developing more efficient trapping methods for C. vesuviana to enhance pest control in ber orchards.

A field experiment was conducted during 2025 (April–August) at Department of Horticulture, College of Agricultural Technology, Kullapuram to study the effect of foliar application of biostimulants on growth, yield and quality of marigold (Tagetes erecta L.). The petals served as an excellent source of xanthophylls, with lutein accounting for 80–90 % of the total content, underscoring its significance beyond floriculture. The experiment consisted of five treatments viz., Fish Amino Acid at 3%, Panchagavya at 3%, Seaweed Extract at 3%, Vermiwash at 3%, and Control, laid out in a Randomized Block Design with four replications. Among the treatments, foliar application of Fish Amino Acid at 3% markedly enhanced growth parameters such as plant height (63.22 cm), number of branches (24.19) and number of leaves (251.15). It also recorded the highest physiological traits, including chlorophyll (49.34 SPAD) and leaf area (9.07 cm²). Yield attributed were similarly improved, with earliest flowering (34.73 days), maximum flower number (48.84), greatest individual flower weight (20.03 g), highest flower yield plant-1 (978.27 g) and longest vase life (6.57 days). The findings confirmed that foliar application of biostimulants, particularly fish amino acid, was a highly effective method for improving the overall growth, yield, and quality of marigold.

In the Rabi season of 2024, a field experiment was conducted in the village of Ahilandapuram to identify the effects of integrated plant nutrition system (IPNS) and foliar nutrition on maize growth, yield and quality parameters. Using maize as the test crop, the experiment was conducted using a randomized block design with 13 treatments and 3 replications. The treatments included the control (T1), 100 % soil test crop response- integrated plant nutrition system (STCR-IPNS) alone, 75 % STCR-IPNS alone and foliar application products: TNAU Maize Maxim, TNAU PPFM, Aloe vera leaf extract and amino acids. The treatment T12, which received 100 % STCR-IPNS along with foliar application of TNAU Maize Maxim, TNAU PPFM, Aloe vera leaf extract and amino acids, recorded the maximum leaf area index. Noticeably, the same treatment (T12) also recorded the best performance in 100-grain weight, cob weight, number of grains per cob and number of grains per row. Interestingly, the same treatment (T12) showed the greatest increase in quality parameters such as crude protein and crude fibre. Based on these findings, the combined use of STCR-IPNS along with a foliar spray of TNAU Maize Maxim + TNAU PPFM+ A. vera leaf extract + amino acid (T12) can be considered one of the most efficient methods for improving the growth, yield and quality characteristics of maize.

Hibiscus cannabinus L. (Mestha) is an underutilized multipurpose crop of the Malvaceae family, traditionally cultivated for its bast fiber but increasingly recognized for its nutritional, medicinal, and industrial potential. The growing challenges of global food insecurity and climate change have renewed interest in resilient crops such as mestha, which thrives under diverse agroecological conditions and offers substantial nutritional and economic benefits. Mestha leaves and seeds are rich in proteins, minerals, vitamins, and bioactive compounds such as phenolics, flavonoids, and saponins, conferring antioxidant, anti-inflammatory, and hepatoprotective properties. The crop’s adaptability to low-input systems and high biomass productivity make it suitable for sustainable agriculture and bioresource utilization. Beyond fiber production, mestha serves as a leafy vegetable, functional food ingredient, and feed source, with emerging applications in nutraceutical, pharmaceutical, and cosmetic industries. Its lignocellulosic biomass also holds promise for bioenergy, bioplastics, and eco-friendly packaging. Despite these advantages, mestha remains underexploited due to limited awareness and research. Future research priorities include genetic improvement, value-added product development, and policy support to enhance commercialization. Promoting mestha as a food, feed, and industrial crop can contribute significantly to food security, climate resilience, and sustainable development.

The utilization of treated municipal sludge or biosolids, as an organic soil enhancer has garnered significant interest for its potential to enhance soil quality and plant growth. The use of treated sludge as an amendment is seen as a viable method for waste disposal and soil improvement. The impact of sludge applications on soil properties, microbiome and flower crop growth and yield depends on factors such as sludge composition, application rates and specific plant species. Safety concerns regarding contaminants such as heavy metals, pathogens and organic pollutants have raised questions about practical application, especially in flower crop cultivation. Despite its potential benefits, challenges like insufficient infrastructure, regulatory awareness and risks of improper handling hinder widespread adoption of municipal sludge as a flower crop soil amendment. Yet, ensuring proper treatment processes and adherence to regulatory guidelines is vital to mitigate potential risks. This review provides an overview of the current status and potential challenges related to the usage of municipal sludge as a soil amendment for flower crops. Addressing these challenges necessitates enhanced sludge management, infrastructure investment and sustainable integrated strategies. Continuous research is crucial to optimize treatment, create value-added products and understand long-term impacts of sludge on soil and environmental sustainability in flower crops.