Rice straw biostimulants: Phytochemicals and effects on maize growth and tomato yield

Biostimulants offer sustainable alternatives to enhance plant growth, resilience and crop yield, especially in organic farming. This study aimed to develop a nutrient-enriched biostimulant from rice straw, a widely available agricultural by-product, often burned, leading to environmental pollution. Rice straw was collected, processed and extracted using cow urine and deionized water (1:50). The extracts underwent phytochemical analysis via GC-MS and LC-MS, identifying bioactive compounds such as fatty acids, sterols, phenols and flavonoids. Elemental analysis confirmed the presence of key nutrients and trace elements, including potassium and magnesium, essential for plant growth. In-vitro assays on maize (CO6 hybrid) evaluated the biostimulant’s efficacy, showing a 12 % increase in germination and a 25 % improvement in seedling vigor at optimal cow urine extract concentrations (CE) (25 %). Root length and shoot biomass also exhibited significant improvements. Field experiments on tomato cultivar (Madhan hybrid) compared the effects of the rice straw-based biostimulant with panchagavya, a traditional organic preparation, alongside controls including cow urine and water. The findings revealed that the rice straw-derived biostimulant markedly improved fruit yield by 22 % compared to the control. This enhancement exceeded that of panchagavya, which achieved a 17 % increase in fruit yield. These results underscore the superior efficacy of the rice straw-based treatment, especially those extracted with cow urine, in enhancing crop productivity, reducing reliance on synthetic agrochemicals and promoting environmentally sustainable agricultural practices.