ASHS 2024 Conference

Tomato stands out as a premier high-value specialty crop globally. However, the inefficiency of conventional fertilizers in nutrient utilization necessitates excessive fertilization to maintain tomato yields, which adversely impacts fruit quality. Nanotechnology, aimed at precise nutrient management to enhance efficiency and economic viability in farming, is gaining attention in agriculture. Similarly, salicylic acid (SA) has emerged as a potential chemical inducer to enhance plant metabolic activities, stress tolerance, and crop yield in the face of climate change. Our two-year field study aimed to assess the impact of varying rates of nano NPK fertilization and SA chemigation on the phytochemical properties, nutritional quality, and fruit attributes of processing tomatoes (Solanum Lycopersicum L., cv. BHN685), relative to conventional fertilization. Employing a two-factorial drip-irrigated plasticulture setup in a completely randomized design, we tested four levels of nano NPK (0, 40, 80, and 120 kg/ha) and two levels of SA (0 vs. 0.3%), each replicated four times. Results showed that tomato fruits subjected to SA chemigation with nano-NPK fertilization exhibited a significant increase in concentration of phytochemicals. Notably, vitamin-A, vitamin-C, lycopene, β-carotene, polyphenol, flavonoid, anthocyanin, and antioxidant capacity displayed substantial increases ranging from 2.5% to 51.2% compared to the control. Particularly noteworthy were the remarkable enhancements in flavonoid and anthocyanin concentrations, registering at 50% and 51.2%, respectively. Conversely, application of nano NPK alone led to discernible increases solely in flavonoid and anthocyanin concentrations, accompanied by decreases in other phytochemicals. Further analysis underscored the synergistic benefits of SA and nano-NPK, resulting in superior color, taste, and phytochemical richness of tomato fruits. K-means cluster analysis corroborated the efficacy of the SA with nano NPK (120 kg/ha) treatment in eliciting optimal fruit characteristics. Moreover, quality assessment revealed the superiority of the SA nano-NPK (120 kg/ha) treatment, with a quality index of 0.61 compared to the control's 0.47, indicative of its superior attributes. Additionally, the nutritional quality index demonstrated a gradual increase in nutrient enrichment across treatments, with the SA and nano NPK (120 kg/ha) combination yielding the highest score. In conclusion, our study highlights the pivotal role of SA in conjunction with nano NPK (120 kg/ha) in enhancing tomato phytochemical content and overall fruit quality. These findings bear significant implications for optimizing horticultural practices and promoting sustainable food production endeavors.