[Effects of micro-sprinkling hose length and width on wheat field water condition and flag leaf chlorophyll fluorescence characteristics in different sampling districts].

A two-year field experiment was conducted in 2014-2015 and 2015-2016 wheat growing seasons to study the effects of micro-sprinkling hose length and width on field water condition, and flag leaf chlorophyll fluorescence characteristics in different sampling districts (D to D along with the hose laying direction). Six micro-sprinkling hose treatments were set: 60 m (T), 80 m (T) and 100 m (T) lengths under 65 mm width; 60 m (T), 80 m (T) and 100 m (T) lengths under 80 mm width. The results showed that after irrigation at jointing, the Christiansen uniformity coefficient (C) of T was significantly higher than T and T under 65 mm hose width. Under 80 mm hose width, T and T had the highest C compared to T. After irrigation at anthesis, the C showed T>T>T under 65 mm hose width, and T>T>T under 80 mm hose width. Under 65 mm hose width, the average relative soil water content of 0-40 cm soil layers after irrigation at anthesis, flag leaf Φ, NPQ and ETR at 20 and 30 d after anthesis and the grain yield of different sampling district did not differ in T; T showed the order of D, D>D>D>D; T showed D, D>D>D>D, D. The average Φ, NPQ and ETR at 20 and 30 d after anthesis, and the average dry matter at maturity of different sampling districts were presented as T>T, T. Under 85 mm hose width, no significant differences were observed in the average relative soil water content of 0-40 cm soil layers after irrigation at ahthesis, flag leaf Φ, NPQ and ETR at 20 and 30 d after anthesis and the grain yield of different sampling districts in T; in T, the indexes mentioned above in D, D and D sampling districts were significantly higher than those in D and D; in T, the decreasing order was D, D, D>D>D>T. The average Φ, NPQ and ETR at 20 and 30 d after anthesis, and the average dry matter at maturity of different districts showed the order of T, T>T. The ave-rage grain yield and water use efficiency of T, T and T were significantly higher than those in T, T and T, T and T had a better irrigation benefit than T. Under this experimental condition, T treatment under 65 mm hose width, T treatment under 80 mm hose width were the most recommendable treatments considering high yield and water saving, and T treatment was also recommendable under 80 mm hose width.