Long‐Term Tillage and Rotation Effects on Corn Growth and Yield on High and Low Organic Matter, Poorly Drained Soils

Abstract

Little information is available that evaluates long-term use of a range of tillage systems and different cropping sequences on poorly drained soils. This study relates corn (Zea mays L.) growth and yield to several reduced tillage systems used with continuous cropping and a corn-soybean (Glycine max L.) rotation. Experiments were conducted on Chalmers silty clay loam (fine-silty, mixed, mesic Typic Haplaquoll) with 40 g kg-• organic matter for 12 yr, and Clermont silt loam (fine-silty, mixed, mesic Typic Ochraqualf) with 10 g kg-• organic matter for 7 yr. Both soils are nearly level and poorly drained. Tillage systems compared included moldboard plowing, chisel plowing, ridge planting, and no-till planting. Shallow disking (10 em) was also included at the Clermont site. On the high organic matter Chalmers soil, continuous no-till corn was 25 em shorter at 8 wk, 2% wetter at harvest, and 9.2% lower in yield compared to plowing. Data for chisel and ridge systems were intermediate between plowing and no-till. No-till yields were consistently lower than those for plowing after the first 4 yr. When following soybean, no-till corn was 7 em shorter at 8 wk, 1% wetter at harvest, and 2.6% lower in yield than corn under moldboard plowing. Corn growth and yield from chisel and ridge treatments were equal to those with plowing when in rotation. On the low organic matter soil in continuous notill corn, plant growth and yields were reduced for the first 3 yr, but were equal or better, compared to plowed corn, for the final4 yr. In rotation, no-till corn was equal to plowed corn the first 3 yr and significantly better in 3 of the last 4 yr. Yields with intermediate tillage were similar to plowed yields for continuous and rotational cropping. The relative advantage for no-till planting with time on the low organic matter soil is attributed to improved soil physical properties.

A meta-analysis of long-term effects of conservation agriculture on maize grain yield under rain-fed conditions

“…However, Van Doren et al (1976) reported that maize grain yields are insensitive to tillage over a wide range of soil textures, cropping systems, climate conditions and experiment durations as long as equal plant densities and adequate weed control were maintained. The reduction in crop yields on poorly drained soils under conservation agriculture was also reported by Griffith et al (1988). Increased yields on well-drained soils are attributed to more efficient use of water and improved physical properties (Griffith et al 1986).…”

“…The reduction in crop yields on poorly drained soils under conservation agriculture was also reported by Griffith et al (1988). Increased yields on well-drained soils are attributed to more efficient use of water and improved physical properties (Griffith et al 1986). Low yields in poorly drained soils are attributed to allelopathy (Yakle and Cruse 1984) and plant pathogens (Tiarks 1977).…”

“…Higher yield for no-tillage in rotation than in monocropping is attributed to a combined effect of multiple factors that include reduced pest infestations, improved water use efficiency, good soil quality as shown by increased organic carbon, greater soil aggregation, increased nutrient availability and greater soil biological activity (Van Doren et al 1976;Griffith et al 1988;Hernanz et al 2002;Wilhelm and Wortmann 2004;Agyare et al 2006;Kureh et al 2006). Other authors report that there is often a larger increase in yield in low-yielding environments than in high-yielding environments (Lauer and Oplinger 1996;Porter et al 1997).…”

“…In two seasons of contrasting total rainfall, the conventional tillage practice had considerably higher yields than the mulched and reduced tillage treatments, suggesting the absence of benefits of tillage when extreme weather events occur. The low yield during the high rainfall years could be attributed to water-logging that affected nutrient uptake and crop growth (Griffith et al 1988). The water conservation effect of mulch on maize yield under low rainfall was not observed during the drought of 1991/1992 (Nehanda and Munyati 1999;Moyo 2003).…”

Influence of tillage on soil macropore size, shape of top layer and crop development in a sub-humid environment

“…In contrast, data from the other three years of the experiment show significant differences between treatments, with the CT:NT ratio reaching a value close to 2 (4 th year, barley). This different response might be related with different factors such as irregular rain distribution (both within and between years), variability of local conditions of soil preparation, or soil moisture content at the time of seeding (Griffith et al 1988). The number of pores classified was 65890, of which 36304 corresponded to the CT treatment (0.005 < EPD < 7.395 mm, average = 0.3073 mm and STD = 0.2794, Q1 = 0.1518, Q2 = 0.2228, Q3 = 0.3604, skewness = 5.23).…”