Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.
Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
Wheat production in a furrow-irrigated bed system in northwest Mexico
Abstract
In the Yaqui Valley, Northwest Mexico, wheat is planted as a winter crop on raised beds with two or three rows seeded on the top of the bed. After harvesting, crop residues are burned to facilitate seedbed preparation for maize as the summer crop. This practice has undesirable environmental consequences. This research was initiated in 1992/93 to determine the feasibility of two tillage systems (conventional, CT, and reduced tillage, RT) combined with five crop residue practices (all incorporated, all left as stubble, partly removed, all removed, and all burned) and seven nitrogen (N) treatments for wheat production in raised beds. Reduced tillage/all straw left as stubble and RT/all straw burned treatments produced the greatest average wheat grain yields of 5.57 and 5.25 Mg ha$\sp{-1}$ of all tillage/straw treatments over the five years of study. However, the grain yields of these two treatments as a function of the environment (defined as mean wheat grain yield per year) was different; RT/all straw left as stubble was superior in high yielding environments, and in contrast RT/all straw burned produced higher yields in low yielding environments. Nitrogen application to wheat at the 1$\sp{\rm st}$ node stage produced greater grain yields 60% of the time compared to basal N fertilizer applications. Soil evaluation showed that RT/all straw burned treatments had the greatest soil strength, the largest soil fractionation, and the lowest soil microbial biomass carbon (SMB), while RT/all straw left as stubble was exactly the opposite to RT/all straw burned, having lowest soil strength, lowest soil fractionation, and highest SMB. Leaving all straw as stubble in a reduced tillage system had potential to replace the burning practice. However, the feasibility of this practice combined with N applications at the 1$\sp{\rm st}$ node wheat stage should be more throughly investigated for adequate fertilizer recommendations.
Subject Area
Agronomy|Soil sciences|Botany
Recommended Citation
Limon-Ortega, Agustin, "Wheat production in a furrow-irrigated bed system in northwest Mexico" (1998). ETD collection for University of Nebraska-Lincoln. AAI9838597.
https://digitalcommons.unl.edu/dissertations/AAI9838597