Pesticide productivity, host-plant resistance and productivity in China

Pesticides are used as the primary method of pest control in Asian rice production. Conditions in China have led to demand for high and increasing rice yields, resulting in intensive cultivation and adoption of fertilizer responsive varieties. The consequence has been widespread pest infestations. Many studies have estimated pesticide productivity, but few have estimated the productivity of alternative methods of pest control, namely host-plant resistance. None have estimated the substitutability between these methods of pest-control. The productivity of pesticides and host-plant resistance, and the substitutability between them is measured using two-stage Cobb-Douglas and translog production functions. Under intensive rice production systems in eastern China, pesticide productivity is low compared to the productivity of host-plant resistance. In fact, returns to pesticide use are negative at the margin. Host-plant resistance is an effective substitute for pesticides and substantial reductions in pesticide use could be achieved, with no loss in rice production, through improvements in host-plant resistance. These results suggest that pesticides are being overused in eastern China and host-plant resistance is being underutilized. Government policies to promote increased pesticides in rice might be ill advised given the low productivity and negative returns, particularly in light of well known negative externalities associated with pesticide use. (C) 1998 Elsevier Science B.V. All rights reserved.