Yield increasing effect of precision automatic fertilization and micro-spray irrigation for winter wheat-summer maize in large-scale

Abstract: To illustrate the agronomic and economic effects of precision automatic fertilization and micro-spray irrigation technology on the winter wheat and summer maize, 3 field experiments were conducted in Beimeng village(38°14′24.87′′N, 114°46′56.41′′E), Fengshang village(38°13′ 21.6′′N, 114°46′48′′E) and Wangxia village(38°2′44.17′′N, 115°25′32.98′′E) in Xinji City Gaocheng District from October 2016 to June 2018. Each experiments including 2 treatments of CK and precision automatic fertilization and micro-spray irrigation treatment, the plot area is 6.67 hm2 for each treatment with 3 replication at random arrangement. The study areas belongs to the typical winter wheat and summer maize rotation in the northern North China Plain, and belongs to the semi-humid climate in warm temperate zone. The average annual temperature is 12.4-12.6 ℃, the accumulated temperature is 4 181-4 863 ℃, the annual precipitation is 488.2-498 mm, and the frost-free period is 190-209 days. The winter wheat sown in mid-October, and harvested in next mid-June, the maize sown in mid-June and harvested from the end of September to the beginning of October. Totally 2 winter wheat-summer maize rotation seasons were included in this experiments. For CK treatment, the fertilization rates and allocation budgets were based on farmers' survey in the experiments areas. The winter wheat fertilization rates was N 216, 231 and 268.5 kg/hm2, P2O5 112.5, 120 and 105 kg/hm2, and K2O 112.5, 37.5 and 75 kg/hm2 respectively for each teat sites. All the P and K fertilizer applied before sowing, 52%-61% N as basal fertilizer applied before sowing and 39%-48% applied at shooting stage as topdressing. The summer maize fertilization rates were N 306, 318 and 294 kg/hm2, P2O5 36, 48 and 60 kg/hm2, K2O 36, 24 and 48 kg/hm2 respectively for each teat sites, all the P and K fertilizers applied as basal fertilizer, 53%-57% N as basal fertilizer applied before sowing and 43%-47% applied at 10 leaf stage as topdressing. The irrigation strategy for CK treatment was flooding irrigation. For precision automatic fertilization and micro-spray irrigation, fertilization rates and allocation budgets were based on agriculture experts knowledge. The winter wheat fertilization rates were N 157,180 and 180 kg/hm2, P2O5 90, 90 and 101.5 kg/hm2, K2O 52.5, 75 and 75 kg/hm2 for each teat site. The allocation proportion for N as basal fertilizer, jointing stage topdressing and booting stage topdressing was 42.5%, 42.5% and 15%, respectively. P2O5 was 65%, 5%, 30%, respectively. K2O was 60%, 20%, 20%, respectively. The summer maize fertilization rates were N 210, 240 and 270 kg/hm2, P2O5 37.5, 43.5 and 45 kg/hm2, K2O 52.5, 60 and 67.5 kg/hm2 for each teat sites. The allocation proportion for N as basal fertilizer, 10 leaf stage topdressing and flowering stage topdressing was 50%, 45% and 5% respectively, P2O5 was 60%, 20% and 20% respectively, K2O was 50%, 30% and 20% respectively. For this treatment, the precision automatic fertilization and micro-spray irrigation was used in the whole growth seasons, fertilizers were accompanied with the irrigation water through the automatic irrigation channel system. The results showed that large scale the precision automatic fertilization and micro-spray irrigation technology used on winter wheat and summer maize could increase the crop yield, decrease the N, P fertilizer application and irrigation water amount, improve the net benefit. Compared with CK, the precision automatic fertilization and micro-spray irrigation technology significantly increased winter wheat yield by 10.6%, increased net income by 43.77%, significantly reduced the production cost by 26.17%, reduced the amount of nitrogen and phosphorus by 24.20%, decreased the irrigation water by 57.45%. Correspondingly, precision automatic fertilization and micro-spray irrigation technology significantly increased summer maize yield by 13.73%, maize net benefits increased by 13.73%, reduced the production cost by17.09%, reduced the amount of nitrogen and phosphorus by 20.34%, decreased the irrigation water by 36.94% than the CK treatment. For the whole winter wheat and summer maize rotation season, the precision automatic fertilization and micro-spray irrigation technology significantly increased the crop yield by 12.26%, increased the net benefits by 37.39%, reduced the production cost by 21.85%, reduced the amount of nitrogen and phosphorus by 22.26%, reduced the irrigation water by 46.51%. This study confirmed the effect of precision automatic fertilization and micro-spray irrigation technology on winter wheat and summer maize, which can provides reference basis for the promotion of this new technology, thus promoting productivity and agricultural sustainable development.