Effects of topdressing depth and row spacing on the SPAD and plant height of winter wheat

Abstract. The objective of this study is to evaluate the effect of depth of topdressing fertilization on the SPAD value and plant height during whole growth stage of winter wheat. Experiments were conducted for one growing season under field conditions with three different kinds of row spacing (10+20) cm, (12+18) cm and (15+15) cm were chosen based on wheat agronomy in north China. The topdressing depth of (3-4, 5-6, 7-8 and 9-10 cm) was applied in (10+20) cm and (12+18) cm row spacing block, fertilizer was scatered on the surface in block (15+15) cm as control group. The results showed that row spacing did not significantly affect the SPAD but significantly affect plant height of winter wheat, depth of fertilization had a significant effect on SPAD and plant height. Plant height measured in block of (10+20) cm row spacing was higher than block (12+18) cm. The SPAD and plant height had a higher value at deth 7-8 cm than other depth treats in block (10+20) cm and (12+18) cm, which also higher than block (15+15) cm. Thus, row spacing set as (10+20) cm, depth of topdressing fertilization at 7-8 cm was the best treats in this study.