Crop diversification of cotton (Gossypium hirsutum) based cropping system for high resource use efficiency

Cotton production is labour intensive in almost all the developing countries where it is picked by hand. However, due to acute labour shortage in recent times, mechanized harvesting is gaining momentum. Mechanized harvesting requires the application of defoliants, which reduces the cost of labour used for picking cotton and maximum cotton can be picked in a single pick (one picking) and providing timely sowing of next crop. So, farmers can get benefit of two crops instead of one single long duration cotton crop. Researchers have conducted various studies on defoliation in cotton using different chemicals and different defoliation methods. However, in India their usage could not be exploited much due to their limited availability.

A field experiment entitled “Studies on defoliants in high density planting cotton-greengram sequence” was conducted during 2018–2019 and 2019–2020 on clay soils at Agricultural College Farm, Bapatla. Crop diversification of cotton with pulses (Greengram) is an alternative cropping system for monocropping of cotton to get higher returns and high land use efficiency.

Total cotton equivalent yield was highest with dropp ultra @ 250 ml ha⁻¹ (D₁) which was on par with Etherel @ 3000 ppm (D₃) in 2018 and in pooled data. 80% boll opening recorded maximum total cotton equivalent yield, which was on par with node above cracked boll. Land use efficiency and production use efficiency were highest in late sown (80% boll opening) plots. The highest net returns and returns per rupee investment were noticed with application of defoliant dropp ultra @ 250 ml ha⁻¹ (D₁) and at 80% boll opening.