[Effects of micro-sprinkling hose irrigation with different hose lengths on soil water distribution, dry matter accumulation, and grain yield of wheat fields].

To explore the optimal hose length of micro-sprinkling hose irrigation in wheat fields, a field trial taking JiMai 22 as test material was carried out in two growing seasons (2015-2016 and 2016-2017). Three lengths of micro-sprinkling hoses with 80-mm width were used, including 60 m (T1), 80 m (T2) and 100 m (T3). The length of trial plot was equal to the hose length. The trial plots were divided to different sample sections every 20-m length along the irrigation direction, which were named as A, B, C, D and E sections, respectively, to examine the effects of micro-sprinkling hose irrigations with different hose lengths on soil water distribution, dry matter accumulation and grain yield of wheat fields. The results showed that: 1) After irrigation at the jointing and anthesis stages in the two growing seasons, the relative soil water content in the 0-40 cm soil layer showed T1<T2<T3 in the A section, T1, T2<T3 in the B section, T1>T2, T3 in the C section and T2>T3 in the D section. The CV of relative soil water content in different sections in the same treatment showed T1<T2<T3. 2) Leaf area index and the rate of canopy photosynthesis active radiation interception at 20 d and 30 d after anthesis, and dry matter accumulation amount after anthesis and at the maturity stage had no significant differences in the A or B section among different treatments. Those indices showed T1>T2, T3 in the C section and T2>T3 in the D section. Leaf area index and rate of canopy photosynthesis active radiation interception at 20 d and 30 d after anthesis and dry matter accumulation amount after anthesis showed T1, T2>T3, and dry matter accumulation amount at the maturity stage showed T1> T2>T3. 3) In the two growing seasons, grain yield in the A and B sections had no significant differences among different treatments, and that showed T1>T2, T3 in the C section and T2>T3 in the D section. Grain yield of each treatment showed T1, T2>T3. 4) The grain yield and water use efficiency showed T1> T2>T3, and the irrigation water use efficiency showed T1>T2>T3 among different treatments in the two growing seasons. Considering grain yield and water use efficiency, hose irrigation with micro-sprinkling hose at 80-mm width and 60-m length was optimal treatment for water-saving and high-yield irrigation, and the suboptimal length was 80 m under this condition. The results could provide theoretical basis for water-saving and high-yield irrigation with micro-sprinkling hose in wheat fields in Shandong Province.