Enhancing Rice Productivity and Soil Nitrogen Using Dual-Purpose Cowpea-NERICARice Sequence in Degraded Savanna  

作　　者：Sylvester O. Oikeh Abibu Niang Robert Abaidoo Pascal Houngnandan Koichi Futakuchi Brahima Kone Amadu Toure 

机构地区：[1]Africa Agricultural Technology Foundation (AATF), Nairobi PO Box 30709-00100, Kenya [2]Africa Rice Center (AfricaRice), Cotonou O1 BP 2031, Benin Republic [3]Department of Biological Sciences, Kwame Nkrumah University of Science and Technology (KNUST), KumasL Ghana [4]Laboratory of Microbial Ecology, Faculty of Agronomy, University of Abomey-Calavi (FSA,/UAC), Cotonou O1 B.P. 526, Benin

出　　处：《Journal of Life Sciences》2012年第11期1237-1250,共14页生命科学（英文版）

摘　　要：ISFM （integrated soil fertility management） involving annual sequencing of dual-purpose early-maturing first crop of cowpeas with biomass incorporation before seeding second crop of early-maturing NERICA （New Rice for Africa） was evaluated to enhance rice productivity and soil-nitrogen. Five dual-purpose early-maturing cowpea cultivars and local cultivar （Katche） were seeded early in the wet season in five farmers＇ fields at Ouake （9046＇ N, 1°35′ E, highly degraded-savanna）, Benin. After pod harvest, cowpea residues were minimally worked into the soil using minimum tillage with hand-hoe and seeded with early-maturing, resilient NERICA8 rice that received either 20 kg N/ha or zero-N. Cowpea grain yield averaged 0.1-0.3 Mg/ha, and mean aboveground cowpea biomass produced and recycled was 0.54-0.64 Mg/ha among best cultivars （IT97-568-11 and IT89KD-288）. NERICA8 seeded after cowpea cv. IT97-568-11 and supplied with 20N gave the greatest grain yield of about 2.0 Mg/ha, accounting for 500% heavier grains than fallow-rice rotation with zero-N. Mineral-N dynamics monitored under NERICA8 in year 2 showed that previous IT97-568-11 plots had the highest mineral-N at tillering which persisted till panicle initiation stage. The adoption of an ISFM comprising annual cowpea-NERICA sequence by smallholder rice farmers could enhance productivity and improve N-supply in fragile savannas.

关 键 词：Degraded savanna dual-purpose cowpea ISFM NERICA rice rice productivity soil nitrogen West Africa. 

分 类 号：S153.61[农业科学—土壤学] S812.8[农业科学—农业基础科学]