关键词: 冬小麦, 硫, 控释肥, 硫加树脂包膜尿素, 干物质积累与分配

Abstract: A field experiment was conducted to study the effects of sulfur plus resin-coated urea fertilizer on the winter wheat dry matter accumulation and allocation and grain yield. Four treatments were installed, i.e., sulfur plus resin-coated urea (SRCU), resin-coated urea (RCU), sulfur-amended conventional urea (SU), and conventional urea (U). The coated urea fertilizers were applied as basal, and the conventional urea fertilizers were 50% applied as basal and 50% applied as topdressing. There were no significant differences in the plant dry matter accumulation and grain yield between treatments RCU and U. Under the conditions the available S content in 0-20 cm soil layer was 43.2 mg·kg^-1 and the S application rate was 91.4 kg·hm^-2, treatments SRCU and SU had no significant differences in the dry matter accumulation and allocation after anthesis and the grain yield, but the amount of the assimilates after anthesis allocated in grain, the grain-filling rate at mid grain-filling stage, the 1000-grain weight, and the grain yield in the two treatments were significantly higher than those in treatment RCU. When the available S content in 0-20 cm soil layer was 105.1 mg·kg^-1 and the S application rate was 120 kg·hm^-2, the grain yield in treatment SRCU was significantly higher than that in treatment SU, but had no significant difference with that in treatments RCU and U. These results suggested that from the viewpoints of dry matter accumulation and allocation and grain yield, the nitrogen released from SRCU had the same regulation effect as the conventional urea 50% applied as basal and 50% applied as topdressing, while the regulation effect of the sulfur released from SRCU was controlled by the available S content in 0-20 cm soil layer. When the soil available S content was 43.2 mg·kg^-1, the released sulfur could promote the dry matter accumulation after anthesis and the grain-filling, and increase the grain yield significantly; when the soil available S content was 105.1 mg·kg^-1 the released sulfur from SRCU had no significant effect in increasing grain yield. Excessive S-amendment could even induce the decrease of grain yield.

Key words: winter wheat, sulfur, controlled release fertilizer, sulfur plus resin-coated urea, dry matter accumulation and allocation