Productivity and biological efficiency indices of sesamum + cowpea intercropping system in response to row ratio and nutrient management

Field experiment on sesamum + cowpea intercropping system was carried out to assess the yield advantage of the system using biological indices, viz., land equivalent ratio (LER), relative crowding coefficient (RCC), aggressivity (A), competition index (CI), competition ratio (CR), sesamum equivalent yield (SEY) and percentage yield difference (PYD). The study was conducted at College of Agriculture, Vellayani, Thiruvananthapuram during the summer season of 2023. The experiment treatments comprised of combinations of three factors, viz., three levels of nitrogen (N) (n₁ - 100 % RDN; n₂ - 75 % RDN; n₃ - 50 % RDN), two row ratios (R) (r₁ - 4:2; r₂ - 6:3) and application of AMF (A) (a₁ - without AMF; a₂ - with AMF). The seed yield of sesamum and cowpea were significantly influenced by individual and interaction effects of treatments. Irrespective of the treatments applied all the intercropping systems showed advantage in terms of LER, CI and PYD. The component crop cowpea was observed with positive (+) aggressivity and higher (>1) CR indicates the dominance of cowpea over sesamum. The intercropping system with the treatment combination 100 % RDN at 6:3 row ratio without AMF (n₁r₂a₁) resulted in higher LER (2.40), RCC (66.18), SEY (1801), and PYD (139.87%).