Acidity amelioration by co-application of biochar and other organic amendments with liming materials and its effect on growth and productivity of tomato

A field experiment was conducted in a laterite soil at the instructional farm, College of Agriculture, Vellayani, Thiruvananthapuram, from June to September 2023 to investigate the combined effect of organic and inorganic amendments on growth characteristics of tomato variety Vellayani Vijai. The treatments included coconut frond biochar (CFB) at 10 t ha^-1 with calcium silicate (CS) as per lime requirement (LR), CFB at 10 t ha^-1 with dolomite as per LR, farmyard manure (FYM) at 20 t ha^-1 with phosphogypsum (PG) as per LR, FYM at 20 t ha^-1 with CS as per LR and humic acid (HA) at 10 kg ha^-1 with CS as per LR each in combination with NPK as per POP, in addition to the treatments KAU POP, KAU organic POP and absolute control were also added. The application of CFB at 10 t ha^-1 along with CS or dolomite as per LR resulted in a significant increase in growth and yield parameters of tomato. Fruit yield and the number of fruits per plant increased by 25.88% and 37.31%, respectively, for CFB at 10 t ha⁻¹ with dolomite as per LR, and by 30.65% and 34.70%, respectively, for CFB at 10 t ha⁻¹ with CS as per LR, compared to KAU POP. Dry matter production of shoot and root increased by 15.31% and 18.71%, respectively, for CFB at 10 t ha⁻¹ with dolomite as per LR, and by 13.21% and 14.20%, respectively, for CFB at 10 t ha⁻¹ with CS as per LR, compared to KAU POP.