Performance of grain sorghum in summer rice fallows of Southern Kerala

Sorghum is a major millet crop, renowned for its adaptability to various cropping systems and harsh environmental conditions typical of semi-arid regions. Sorghum in paddy fallows is gaining popularity among the farmers in South India. An experiment was conducted at College of Agriculture, Vellayani, from January 2024 to May 2024 to standardize the tillage, plant population and nutrient management for grain sorghum in summer rice fallows. The experimental design was RCBD replicated thrice and the treatments comprised of 12 combinations of two tillage methods (t1-zero tillage, t2-conventionaltillage), two spacings (p1 – 45x15 cm, p2- 60x15 cm) and three NPK levels (n1 – 45:25:25 kg NPK ha-1, n2 – 50:25:75 kg NPK ha-1 and n3 – 50:25:50 kg NPK ha-1).Sorghum grown under conventional tillage with spacing 45x15 cm and a nutrient dose of 50:25:75 NPK kg ha-1 recorded taller plants at harvest (288.03 cm) and higher leaf area index (LAI) at 30 DAS(3.13). Sorghum grown under zero tillage with spacing 45x15 cm and a nutrient dose of 50:25:50 NPK kg ha-1 recorded higher dry matter production (DMP)(11.72 t ha-1) at harvest. Higher grain yield (5.14 t ha-1) was obtained when sorghum was grown under zero tillage with spacing 45x15 cm and a nutrient dose of 50:25:50 NPK kg ha-1, and higher stover yield(8.10 t ha-1) was obtained in sorghum grown under zero tillage with spacing 45x15 cm and a nutrient dose of 50:25:75 NPKkg ha-1. The net income(A 98676) as well as B-C ratio (2.77) was the highest in sorghum grown under zero tillage with 45cm x 15 cm spacing and 50:25:50 kg NPK ha-1nutrient dose followed by sorghum grown under zero tillage with 45 cm x15 cm spacing and 50:25:75 kg NPK ha-1nutrient dose (A 94263). Hence, grain sorghum can be profitably cultivated in summer rice fallows with zero tillage planted at a spacing of 45 cm x 15 cm and application of nutrient dose of 50:25:50kg NPK ha-1 along with 5 t ha-1 FYM