Effects of straw returning combining with sulfur fertilizer on yield, sulfur accumulation and distribution in spring maize

Objective  To explore the effects of straw returning combining with sulfur fertilizer on the yield and sulfur accumulation, distribution and transportation of spring maize, and provide theoretical bases for exploring the accumulation and transportation laws of sulfur fertilizer in spring maize as well as rational application of sulfur fertilizer.

Method  Two-factor split block design was used, the main plot was divided into straw returning and no straw returning, the subplot was divided into sulfur fertilizer application and no sulfur fertilizer, which formed five treatments of CK (no fertilizer), no straw returning and no sulfur fertilizer, no straw returning and sulfur fertilizer, straw returning and no sulfur fertilizer, straw returning and sulfur fertilizer. The effects of straw returning combining with sulfur fertilizer application on the accumulation, distribution and transportation of sulfur in spring maize were studied through the field experiment.

Result  Straw returning combining with sulfur fertilizer had a certain degree of increasing the yield. The maize yield of straw returning and sulfur fertilizer was 11.98% higher than that of straw returning and no sulfur fertilizer, and 20.34% higher than that of no straw returning and no sulfur fertilizer. Straw returning combining with sulfur fertilizer could significantly increase the accumulation of sulfur in spring maize. The sulfur accumulation amount of straw returning and sulfur fertilizer was 13.37% higher than that of no straw returning and sulfur fertilizer, and 52.67% higher than that of no straw returning and no sulfur fertilizer. Sulfur fertilizer application could increase the accumulation of sulfur in plant organs. The sulfur accumulation amount of sulfur fertilizer application treatment was averagely 36.07% higher than that of no sulfur fertilizer application treatment. The sulfur accumulation amount in each organ generally behaved as grain > leaf > stem > ear. Compared with the treatment of no straw returning and no sulfur fertilizer, total sulfur transport amount of straw returning and sulfur fertilizer treatment increased by 74.54%, reaching the highest of 15.29 kg·hm ⁻², and total contribution rate of sulfur transport amount to grain increased by 17.27%.

Conclusion  Straw returning combining with sulfur fertilizer can promote the accumulation of sulfur in spring maize and the transportation of sulfur from vegetative organs to grains, and ultimately improve the yield of spring maize.