Effects of Raised-Bed Planting and High Plant Density on Yield-Increasing of Cotton in the Yellow River Basin

Objective) Raised-bed planting and plant density have been widely studied as a single practice in cotton production, but their combination to approach better yields and benefits was less studied. Since effective combination of raised-bed planting and plant density may further increase cotton yield, it is very important to conduct profound studies on interaction of plant density and raised-bed planting.(Method)A two-year field experiment was carried out to evaluate the effects of raised-bed planting and plant density on earliness, leaf area index, abscission rate of squares and young bolls, yield and yield components. A split-plot design with three replicates was used for the study. The main plots comprised two planting patterns (raised-bed planting and flat planting), while planting densities (3, 6 and 9 plants/m 2 ) constituted the subplots.(Result)Significant interaction was detected between planting pattern and plant density on cotton yield. Flat planting produced the highest cotton yield at medium plant density (6 plants/m 2 ), while raised-bed planting produced the highest and lowest cotton yield at 9 plants/m 2 and 3-6 plants/m 2 , respectively. Raised-bed planting at 9 plants/m 2 was 13.6% higher than traditional flat planting at 6 plants/m 2 . Both planting pattern and plant density significantly affected yield components. Boll weight and earliness under raised-bed planting were higher than those under the flat planting, and the number of bolls/m 2 was increased as plant density rose. Raised-bed planting significantly increased biological yield, ratio of seed cotton to stalk and leaf area index, but decreased the rate of rotted bolls and abscission of squares and bolls. (Conclusion)Planting pattern and plant density affected biological yield, harvest index and yield components individually or interactively, thus resulting in a significant effect on economic yield. It is thus suggested that raised-bed planting at high plant density