Effect Of Intercropping Patterns On Water And Nutrient Use In Maize/Soybean Intercropping Systems In Loess Hilly-gully Region

Water shortage is the main factor limiting crop yields on the Loess Plateau. Selectingrational planting patterns to improve water use efficiency (WUE) is an important means toincrease yields in this area. Intercropping had widespread application in the semiaridconditions on the Loess Plateau, but research about the utilization of water and nutrient underdifferent intercropping patterns still less. The field trial selected two maize cultivars(zhengdan958and yuyu22) and two soybean cultivars (zhonghuang24and zhonghuang13)under monoculture and intercropping (2:2and4:2ratios) respectively, to explore the effect ofmaize and soybean growth、yields、water use and nutrient use under different planting patterns.The results as follows:Among different patterns, intercropping2:2is more advantageous to the growth of maizeand soybean. In the maize/soybean intercropping2:2, the plant leaf area and stem diameter ofmaize and the plant height of maize and soybean were higher than intercropping4:2, maizeand soybean have higher luminous energy utilization rate, in favour of the accumulation ofphotosynthetic products, in the full ripeness period, the dry matter accumulation of maize andsoybean under intercropping2:2were higher than intercropping4:2.Zhengdan958and zhonghuang13under intercropping2:2has obviously yield advantage.The land equivalent ratio (LER) under maize/soybean intercropping greater than1, andintercropping2:2greater than4:2, indicate that2:2has greater intercrop advantage. Themaize yield under zhengdan958and zhonghuang13intercropping2:2higher than othertreatments, and the soybean yield under zhengdan958and zhonghuang24intercropping2:2higher than other treatments. The composite yield of zhengdan958and zhonghuang13intercropping2:2was highest in all intercropping treatments.Zhengdan958and zhonghuang13under intercropping2:2has obviously WUE advantage.The water equivalent ratio (WER) under maize/soybean intercropping greater than1, andintercropping2:2greater than4:2, indicate that2:2has greater intercrop advantage. The maize WUE under zhengdan958and zhonghuang13intercropping2:2higher than othertreatments, and the soybean WUE under zhengdan958and zhonghuang24intercropping2:2higher than other treatments. The LER of zhengdan958and zhonghuang13intercropping2:2was highest in all intercropping treatments.In the aspect of N utilization, yuyu22and soybean intercropping, in the0-30cm soil layer,the soil total N content of maize and soybean were higher than each monoculture, andintercropping4:2higher than2:2, but the soybean aboveground organs showed thatintercropping2:2higher than4:2, illustrated that yuyu22and soybean intercropping4:2promoted the N fixation, and yuyu22had stronger competition ability of N underintercropping4:2.The P and K utilization in maize and soybean depended to the different varieties. Thetwo maize varieties intercropped with zhonghuang24, the total P content of maize andsoybean aboveground organs were intercropping2:2higher than4:2, but there were differentwhen intercropped with zhonghuang13. In each intercropping treatments, the total K contentof maize aboveground organs were intercropping2:2higher than4:2, among them, the total Kcontent of maize stem and leaf under zhengdan958and soybean intercropping were higherthan yuyu22, and intercropping higher than monoculture; the total K content of soybeanaboveground organs were different due to varieties. It can declared that total P and total Kcontent of maize aboveground organs has advantage under intercropping2:2, and soybeanwere vary from varieties.