|Olk, Daniel - Dan|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/10/2005
Publication Date: 11/10/2005
Citation: Buresh, R.J., Lazaro, W.M., Pampolino, M.F., Dizon, M.A., Olk, D.C., Witt, C. 2005. Long-term changes in soil nitrogen supplying capacity in rice-maize and rice-rice cropping systems [CD-ROM]. In: ASA-CSSA-SSSA Annual Meeting Abstracts, Nov. 6-10, 2005, Salt Lake City, UT.
Technical Abstract: Irrigated rice (Oryza sativa L.) ecosystems in Asia are among the most productive agricultural systems in the world. The cropping patterns in these systems is often becoming more diverse and including non-rice crops such as maize (Zea mays L.). We compared in a 12-year-old experiment in the Philippines the long-term effects of continuous rice-rice cropping and a rice-maize rotation on changes in soil nitrogen (N) supplying capacity, N balances, and crop yields. Soil carbon (C) and N decreased in the rice-maize rotation. Indigenous N supply, as determined from the yield of rice and the N accumulation by mature rice in the absence of N fertilizer, was consistently lower when rice followed maize than rice. Yield of rice with full fertilizer application was not affected by the previous crop. Rotation of rice with maize reduced the soil N supplying capacity, but it did not prevent the attainment of high rice yield with sufficient application of fertilizer N. The rotation of rice with maize rather than rice could, however, increase the need of rice for fertilizer N to achieve high yield.