EVALUATION OF TRANSPLANTING BT COTTON IN A COTTON-WHEAT CROPPING SYSTEM

Cotton-wheat is an important cropping system in South Asia. Introduction of BT cotton has caused the time conflict between sowing of BT cotton and wheat harvest in this cropping system. Wheat is harvested in late April but the best planting time of BT cotton is mid-March, which indicates a time conflict of 30-45 days between two crops in the region. However, this conflict can be managed by raising the cotton nursery and transplanting 30-45 days old seedlings in the field after wheat harvest. This two years field study was conducted to assess the economic feasibility of transplanting BT cotton in BT cotton-wheat cropping system at two locations (Multan, Vehari) in the cotton belt of Punjab, Pakistan. The BT cotton-wheat cropping systems included in the study were; flat sown wheat (FSW)-zero-tilled cotton (ZTC), FSW-conventional-tilled cotton (CTC), ridge sown wheat (RSW)-ridge-transplanted cotton (RTC) (30 days old seedlings), RSW-RTC (45 days old seedlings), bed sown wheat (BSW)-bed-transplanted cotton (BTC) (30 days old seedlings) and BSW-BTC (45 days old seedlings). BSW produced more grain yield than RSW and FSW during both years at both locations. Likewise, BTC (45 days old seedlings) had higher production at both sites during both years. The overall productivity of BT cotton-wheat, in terms of net income, benefit: cost ratio and marginal rate of returns, was the maximum from transplanting 45 days old cotton seedlings on beds after BSW during both years at both sites. Sowing cotton as ZTC following FSW was the least productive cropping system. In conclusion, transplanting 45 days seedlings of BT cotton on beds during late April after harvest of BSW wheat may be opted to manage the time conflict and improve the productivity of BT cotton-wheat cropping system in Punjab, Pakistan. © 2016 Cambridge University Press.