Effect of double ridges mulched with wide plastic film on crop yield and water use efficiency in semi-arid areas

A field experiment was carried out on cultivated land of dry farming in the Loess Plateau and spring maize was used as an indicating crop to study the effects of different plastic film mulching patterns,double ridges mulched with wide plastic film and then planting maize in double furrows(SL),wide plastic film mulching on the flat ground(QP),only one ridge mulched with narrow plastic film(TL),narrow plastic film mulching on the flat ground(TP) and non-mulching(CK)) on the soil moisture,on the economic traits and yield of spring maize and water use efficiency(WUE).The results showed that plastic film mulching improved the soil moisture of sowing row,crop economic traits and the ratio of grain yield and biomass remarkably.Among them the treatment SL performed the best in rainwater harvesting and soil moisture keeping.The yield of spring maize with plastic film mulching were all higher than those of non-mulching treatment,and the yield of SL was 6 129.0 kg·hm-2 which was the highest.The order of grain yield from high to low was SLQPTPTLCK.The technology of double ridges mulched with wide plastic film greatly improved the spring maize's water use efficiency which came to 28.95 kg·hm2·mm-1(counted with grain)and 135 kg·hm-2·mm-1(counted with biomass),which were 915.8 % and 156.4 % greater than CK,44.03 % and 42.41 % greater than QP,73.87 % and 24.48 % greater than TL,42.96 % and 22.45 % greater than TP,respectively.Film mulching(especially SL)changed the energy distribution during the middle-later period of crop growing,more energy was given to reproductive growth and higher grain yields were get accordingly.The relative grain yield(Gn/Bs value) of SL was 288.2 % greater than CK,and the order of the relative grain yield(Gn/Bs value) from high to low was SLQPTPTLCK.