TITLE:
Corn and Soybean Rotation under Reduced Tillage Management: Impacts on Soil Properties, Yield, and Net Return
AUTHORS:
Krishna N. Reddy, Robert M. Zablotowicz, L. Jason Krutz
KEYWORDS:
Crop Rotation; Monoculture; Reduced Tillage; Soil Microbial Community; Soil Quality
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.5A,
May
30,
2013
ABSTRACT: A 4-yr field
study was conducted from 2007 to 2010 at Stoneville, MS to examine the effects
of rotating corn and soybean under reduced tillage conditions on soil
properties, yields, and net return. The six rotation systems were continuous corn
(CCCC), continuous soybean (SSSS), corn-soybean (CSCS), soybean-corn (SCSC), soybean-soybean-cornsoybean
(SSCS), and soybean-soybean-soybean-corn (SSSC). Field preparation consisted of
disking, subsoiling, disking, and bedding in the fall of 2005. After the fall of
2006, the raised beds were refurbished each fall after harvest with no
additional tillage operations to maintain as reduced tillage system. The
surface 5 cm soil
from continuous soybean had higher pH than continuous corn in all four years. Unlike
pH, total carbon and total nitrogen were higher in continuous corn
compared to continuous soybean. Delta 15N tended to be higher in
continuous corn compared to continuous soybean. Fatty acid methyl ester (FAME)
indicated minor changes in soil microbial community in relation to cropping
sequence, however there was a significant shift in rhizosphere community
depending on crop. Corn yield increased every year following rotation with
soybean by 16%, 31%, and 15% in 2008, 2009, and 2010, respectively, compared to
continuous corn. As a result, net returns were higher in rotated corn compared
with continuous corn. This study demonstrated that alternating
between corn and soybean is a sustainable practice with increased net returns
in corn.