Effects of soil fertilizer amendment on growth during critical growth stages and yield of winter wheat

Reasonable irrigation and fertilization are key factors of winter wheat production. Field experiments were conducted in 2009~2010 with “Xiaoyan 22” as materials. The effects of soil fertilizer amendment (SFA) on water content along soil profile and growth at critical growth stages and yield of winter wheat were investigated. The results show that yield under SFA treatments was 10%~30% higher than that under normal fertilization (NF) treatment. Optimum SFA increased with increasing irrigation amount. Theoretical maximum yield was 8 894.11 kg·hm^-2, which was under single irrigation with 1 350 kg·hm^-2 SFA. At the start of jointing stage, soil water content under SFA treatments initially increased steadily and then slowly decreased in a V-shaped distribution curve from surface to deep layer along soil profile, quite different from the W-shaped distribution curve under NF treatment. At grain-filling stage, the depth of max and min soil moisture content under SFA occurred much deeper than that under NF treatment. At tillering stage, plants under SFA treatments were low with relatively thick and short roots. This trend was more obvious at higher fertilizer application rates. At grain-filling stage, however, plant height was lowest, spike dry-matter and dry-weight of aboveground part were highest under middle SAF treatment. In the middle of SFA treatment, wheat filling rate was significantly higher than that under all other treatments. Thus SFA deepened the position of max and min soil moisture content along soil profile. Wheat growth rate under SFA was higher than under NF treatment. SFA treatment facilitated optimal production in low water conditions (jointing stage irrigation of 60 mm) than NF treatment.