Effect of methods of crop establishment on productivity and economics of Btcotton (Gossypium hirsutum)–based intercropping systems

A field experiment was conducted at New Delhi during the rainy (kharif) season of 2012, to study the effect of methods of crop establishment, planting geometry and intercrops on yield attributes, productivity and economics of Bt-cotton (Gossypium hirsutum L.)–based intercropping systems. Seed-cotton yield (3.22 tonnes/ha) was 5.23% higher under transplanting than direct sowing, while seed-cotton equivalent yield of intercrop (0.52 t/ha) was 52% higher under direct sowing. Production efficiency (17.7 kg/ha/day) and net benefit: cost ratio (1.92) were also recorded higher under transplanting. Cotton planted at 90 cm × 60 cm spacing recorded significantly higher yield attributes, seed-cotton yield (3.27/3.01 tonnes/ha), system productivity (3.69/3.45 tonnes/ha), production efficiency (18.6/16.6 kg/ha/day), net returns ( 92.2/80.2 × 10³/ha) and benefit: cost ratio (1.99/1.82) than 120 cm × 45 cm planting. Sole cotton recorded 3.25 tonnes seed-cotton yield/ha, which was 6.2% and 4.2%, higher than the seedcotton yield recorded in association with okra [Abelmoschus esculentus (L.) Moench] and cowpea [Vigna unguiculata (L.) Walp.] respectively. Seed-cotton equivalent of cowpea as an intercrop was 10% higher than okra. Cotton + cowpea intercropping system recorded significantly highest system productivity (3.56 tonnes/ha), production efficiency (18.3 kg/ha/day) and net returns ( 86.2 × 10³/ha), while the benefit: cost ratio (2.18) was the highest in sole cotton.