Integration of tricho-compost and tricho-leachate with reduced chemical fertilizer to enhance growth, yield and fruit quality of brinjal

Excessive reliance on chemical fertilizer can undermine soil quality and the sustainability of intensive brinjal production. This study evaluated whether tricho-compost and tricho-leachate could maintain crop performance when the recommended mineral fertilizer dose (RDF) was reduced. A field experiment with BARI Brinjal-4 was conducted at Sylhet Agricultural University in a randomized complete block design with five treatments and three replications: 100% RDF without Trichoderma-based inputs (T1) and 10 t ha −1 Tricho-compost plus 20 mL L −1 Tricho-leachate combined with 100% (T2), 75% (T3), 50% (T4), or 0% (T5) RDF. T2 produced the highest yield (25.76 t ha −1 ) which was 17.5% higher than T1, and also maximized vegetative growth, SPAD value, root length, and biochemical quality while minimizing fruit infestation. Importantly, T3 reduced mineral fertilizer by 25% yet yielded 23.55 t ha −1 , 7.4% more than T1, and increased SPAD value, total phenolic content, total flavonoid content, antioxidant activity, and anthocyanin content by 10.9%, 19.7%, 18.5%, 13.0%, and 25.0%, respectively compared to T1, while reducing infested fruits by 26.0%. T4 reduced mineral fertilizer by 50% and maintained a yield statistically comparable to T1 (22.14 versus 21.92 t ha −1 ), although its quality advantages were smaller. These findings support partial, rather than complete, substitution of mineral fertilizer; under the conditions tested, 75% RDF with tricho-compost and tricho-leachate offered the most practical balance between productivity and fertilizer saving. Multi-location and multi-season validation is required before broad recommendation.