Tuesday, November 14, 2006 - 1:45 PM

Increasing Rice Productivity through Crop Canopy Management.

Roland J. Buresh1, Bui Huy Hien2, Nguyen Cong Vinh2, Pham Sy Tan3, Marianne Samson1, and Shaobing Peng1. (1) IRRI, DAPO Box 7777, Metro Manila, Philippines, (2) National Inst Soils and Fertilizers, Chem, Tu liem, Hanoi, Vietnam, (3) Cuu Long Delta Rice Res Inst, Omon, Can Tho, Vietnam

Rice is the main staple food crop in Asia. About 90% of the global rice production is in Asia, and 75% of rice is produced with irrigation. Rice is established by either transplanting or direct wet seeding. Plant population, fertilizer N, and irrigation water are among the important management factors influencing rice production at the field level. We examined the interactive effects of plant population for transplanted and wet seeded rice, frequency of irrigation, and fertilizer N management on the growth and performance of rice. The results were used to develop a crop canopy-based approach to managing rice for optimal tiller and crop development to achieve a yield target, while minimizing disease often associated with excessive vegetative growth. The management approach initially establishes for the selected cultivar a yield target, which is realistically attainable within the climate and crop growth environment. The yield target is then translated into a healthy crop canopy with a targeted number of panicles and tillers for the cultivar. This is then used to guide early crop management practices such seed rate for wet seeded rice, plant spacing for transplanted rice, fertilizer N management, and water management to achieve the tillering and crop growth required for the targeted crop canopy and yield. Fertilizer N is dynamically managed based on crop need, as determined from leaf color, in order to account for spatial variability in soil fertility and year-to-year variation in climate.