Comparative study of farmers' IPM [integrated pest management] practices for hybrid and inbred rice production in Digos, Davao del Sur, Philippines

This study was conducted from June 2007 to November 2007 in four barangay [villages] of Digos, Davao del Sur to assess the impact of IPM training in rice production practices and productivity of hybrid and inbred rice farms. Fifty farmer-respondents were selected through purposive sampling as survey respondents. Mean, frequencies and percentage were used to describe the characteristics of hybrid and inbred farmers while the t-test analysis was used to identify the differences between variables. The IPM knowledge and skills test of the respondents were determined through structured tests. Results of the test showed respondents' adept knowledge on pesticide management and role of beneficial arthropods in pest management. Results of skills test reveal that hybrid and inbred farmers engaged approximately similar practices or proper water management, proper frequency and period of insecticide and fertilizer application and preference for cultural and biological methods over chemical methods of pest control except in the amount of fertilizers applied. Still, hybrid farmers experienced higher yields during dry season due primarily to the use of high yielding registered seeds which reduced labor cost, cash costs for fertilizer, insecticide, fungicide, molluscicide and herbicide. However, hybrid farmers profited more than inbred farmers due to higher prices. Generally, hybrid variety (6,724.54 kg/ha) yielded better than inbred variety (6,467.33 kg/ha) specifically during dry seasons. However high hybrid rice yield dropped during wet season due its susceptibility to bacterial leaf blight (BLB). Thus, the use of inbred rice during wet season is advantageous provided quality (registered) seeds are used. Peaked population of leafhopper and planthopper was observed in hybrid and inbred variety during maximum tillering and panicle initiation stages. Stem borers adult and eggmass occurred throughout the growing period, however rate deadheart was higher in inbred variety during early vegetable phase while whiteheads were higher in hybrid at reproductive phase. Higher average count of predator, parasitoids and spiders was noted in inbred rice due to the frequency of insecticide sprayed by inbred farmers (two times) while hybrid (four times) throughout the cropping season. In contrast, bacterial leaf blight manifestation was higher in hybrid rice because of inherent climate, soil condition and water management practices.