Drip irrigation systems are becoming more and more mature, and are presently extensively applied to increase crop yield and water use efficiency. In order to investigate the effects of irrigation quota on maize growth, the grain yield, and the water use efficiency (WUE), a field experiment with four irrigation quotas (T1 420 mm, T2 480 mm, T3 540 mm, and T4 600 mm) was conducted from 2013 to 2021 in Xinjiang, China. The results showed significant changes in maize growth, yield, and WUE in response to different irrigation quotas. The plant height, leaf area index, soil and plant analyzer development (SPAD), dry matter accumulation, yield, and harvest index of maize at different irrigation quotas all showed a ‘single peak curve’, and its change was closely related to the irrigation level. The growth index, dry matter accumulation, yield, and irrigation water use efficiency with T3 were the highest. The dry matter transfer efficiency, contribution of dry matter translocation to grain, and the harvest index with T3 showed a significant increase of 13.86%, 26.06%, 29.93%, and 7.62% compared to T1, respectively. In comparison to T1, T2, and T4, the yield of T3 increased by 32.17%, 13.54%, and 11.27%, respectively, and the WUE increased by 16.56%, 6.49%, and 23.70%, respectively. The significant correlations established between the maize yield and irrigation quotas could be simulated by a Kuznets-style relation. The maize yield was negatively correlated with irrigation quotas. When the irrigation quota (x) was 539.12 mm, the maize yield (y) was 16043.92 kg·hm⁻². These results demonstrate that the optimized irrigation quota (540 mm) can effectively improve the growth, yield, and WUE of drip irrigation maize in northwest China. Meanwhile, it can provide a theoretical reference and data support for the optimal amount of irrigation for drip irrigation maize in Xinjiang China.

Mulching is a widely used agricultural water conservation measure in the semiarid regions of Northwest China. In order to explore the response process of different film mulching methods to soil microorganisms, we characterized the effect of different film mulching methods on soil microbial diversity and community structure characteristics in the root zone of drip-irrigated maize during the heading and maturity stages using high-throughput sequencing of 16SrDNA and ITS amplicons combined with bioinformatics analysis. Full mulching (FM) was contrasted to controls of no mulching (NM) and half-mulching (HM), yielding an order of microbial diversity, abundance, and evenness scores of HM > FM > NM. The HM and FM treatments reduced the relative abundance of Proteobacteria and Actinobacteria (the most abundant bacteria) in the bacterial community structure but increased that of Acidobacteria and Chloroflexi. In the fungal community structure, HM decreased the abundance of Sordariomycetes but increased that of Eurotiomycetes (the most abundant fungi). The abundance and community structure of bacteria were significantly correlated with soil temperature and those of fungi with pH. HM improved network complexity and competitive relationships among bacteria, while FM increased the relationship between fungal groups and the symbiosis of fungal communities. HM significantly increased maize yield (20.37% and 6.01% above NM and FM, respectively). In summary, full mulching was more favorable than no mulching for soil microbial diversity and community structure composition, but soil microbial diversity and yield responded better to half-mulching. These results provide a background for improving the yield of drip-irrigated maize and protecting the microbial ecosystems of farmland soils.

Drip irrigation systems are becoming more and more mature and are present extensively applied to increase crop yield and water use efficiency in Xinjiang, northwest China. To investigate the effects of irrigation quota on maize growth, the grain yield, and the irrigation water use efficiency (IWUE), a field experiment with four irrigation quotas (T1 4200m3·hm-2, T2 4800m3·hm-2, T3 5400m3·hm-2 and T4 6000m3·hm-2.) were conducted from 2013 to 2021 in Xinjiang China. The re-sults showed significant changes in maize growth, yield, and irrigation water use efficiency in response to different irrigation quotas. The plant height, leaf area index, SPAD, biomass, yield and harvest index of maize at different irrigation quotas all showed a “single peak curve”, and its change was closely related to the irrigation level. The growth index, dry matter accumulation, yield and irrigation water use efficiency with T3 were the highest. The dry matter transfer effi-ciency, contribution of dry matter translocation to grain and the harvest index with T3 showed significant increase of 13.86%, 26.06%, 29.93% and 7.62% compared to T1, respectively. In com-parison to T1, T2 and T4, the yield of T3 increased by 32.17%, 13.54% and 11.27% respectively, and the irrigation water use efficiency (IWUE) increased by 2.80%, 0.93% and 23.63% respectively. The significant correlations established between the maize yield and irrigation quotas could be sim-ulated by kuznets-style relation. The maize yield was negative correlated with irrigation quotas, When the irrigation quota (x) was 5376.73m3·hm-2, the maize yield (y) was 15841.00m3·hm-2. These results demonstrate that the optimized irrigation quota (5400m3·hm-2 treatment) can effectively improve the growth, yield and irrigation water use efficiency of drip irrigation maize in North-west China. In the meanwhile, it can provide theoretical reference and data support for the op-timal irrigation amount of drip irrigation maize in Northwest Xinjiang.