Peer review

Peer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=0002-1962

New crop rotation and adequate fertilizer management are needed to maintain productivity of high input irrigated wheat (Triticum aestivum L.) systems. This study was initiated in 1998 in northwest Mexico. The objective was to examine the effects of two straw managements (incorporated or burned), three crop rotations [wheat-sesbania (Sesbania spp.), wheat-maize (Zea mays L.), or wheat-fallow], and the application for wheat of three N fertilizer sources (urea, chicken [Gallus gallus] manure, or a mixture of both) at two rates (0 and 200 kg N ha−1) on soil properties. Soil microbial biomass C and N, soil N, P, K concentrations, pH, sodium absorption ratio, electrical conductivity, aggregate size distiribution and stability were evaluated in 2001, 2002, and 2005 during the wheat cropping seasons. Straw management had no consistent effect on the amount of carbon mineralized from the soil microbial biomass (SMB C). Planting sesbania as a summer crop after harvesting wheat in the spring enhanced both SMB C and N. The effect of straw management and crop rotation on aggregate size distribution was minimal. Chicken manure application increased the soil N, P, and K concentration. Potassium was accumulated after burning residues. Enhancing rotation complexity and reducing fallow by including summer maize or sesbania increased the soil organic matter. To enhance the measured soil attributes wheat should be followed by a crop like sesbania in the summer and the use of organic manure should be combined with an inorganic N source allowing a balanced application of nutrients as required by the crop.

Conservation Agriculture Program

Text in English

INT2813|CSAY01