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【Objective】 Maize is a main staple crop cultivated in central and Northern China but it requires irrigation at certain stages during its growth. In this paper, we present the findings of an experimental study on the effect of irrigation amount on photosynthesis and dry matter accumulation of the crop during its tasseling-silking stage. 【Method】 The field experiment was conducted in the long-term experiment established in 2018 at the experimental base of the academy of agricultural and animal husbandry sciences of Inner Mongolia Autonomous Region. The experiment compared six irrigation amounts: 315 m3/hm2 (W1), 645 m3/hm2 (W2), 945 m3/hm2 (W3), 1 275 m3/hm2 (W4), and 1 605 m3/hm2 (W5); the control was rain-fed (W0). During the experiment, we measured photosynthetic characteristics and dry matter accumulation of the crop in each treatment. The photosynthetic characteristics and its correlation with dry matter accumulation were calculated by fitting the response curve parameters to a non-right-angle hyperbolic model. 【Result】 The leaf SPAD in W3 was lower only than that in W4 in 2019, but in 2020 it increased by 3.96%, 5.12%, 11.10%, 12.64% and 19.90%, respectively, compared with that in W4, W2, W1, W5 and W0. In 2019 and 2020, the average daily net photosynthetic rate was the highest in W3, while in 2019, the dry weights of stems, leaves and ears in W3 were the second highest among all treatments. In 2020, the physiological indexes of the crop in W3 were higher than that in other treatments. There was no significant difference in leaf photosynthesis between W3, W4 and W5. 【Conclusion】 In central and western regions of Inner Mongolia, when the total rainfall during growing season of maize exceeded 365 mm, irrigating 945 m3/hm2 of water can effectively improve photosynthetic efficiency of the maize during its tasseling-silking stage, promote dry matter accumulation and increase grain yield.

【Objective】 The purpose of this paper is to investigate the effect of drip irrigation amount on dry matter accumulation and distribution, as well as the yield formation of the grain machine harvest maize. 【Method】 The study was based on the drip irrigation experiment established in 2018 in the Experimental Field of Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences. The experiment consisted of five irrigation treatments by irrigating 415 m3/hm2 (W1), 645 m3/hm2 (W2), 945 m3/hm2 (W3), 1 275 m3/hm2 (W4) and 1 605 m3/hm2 (W5), respectively. A rain-fed plot was taken as the control (CK). In each treatment, we measured the accumulation and distribution of above-ground dry matter in 2020 and 2021. Logistic model was used to describe the temporal change in dry matter accumulation, from which we further analyze the characteristics of dry matter accumulation and distribution, as well as the relationship of drip irrigation amount and yield under different treatments. 【Result】 Irrigation significantly increased the dry matter accumulation in the upper part of the plant; temporal change in the dry matter accumulation is well described by the logistic model, with R2>0.888. In 2020 and 2021, the maximum growth rate of the dry matter accumulation increased as the irrigation amount increased, with the increase in the CK being the least and the increase in W5 being the highest. The biological yield in W5 was the highest in both 2020 and 2021; the harvest index in W4 and W3 was the highest, being 0.51 and 0.50 respectively. Compared with CK, irrigation reduced dry matter distribution in the vegetative organs at maturity stage but increased dry matter accumulation in the grains. With the increase in irrigation amount, the economic yield in 2020 first increased, followed by a decline, maximizing in W4, reaching 14 282.42 kg/hm2 in 2021. The yield in W4 (15 480.33 kg/hm2) and W5 (15 892.52 kg/hm2) was significantly higher than that in other treatments. 【Conclusion】 Optimizing irrigation amount can significantly increase dry matter accumulation in the aboveground part, and promote distribution of dry matter in the grain. In drought years with average annual natural precipitation between 364.2 and 390.7 mm, the optimum drip irrigation amount is 1 275 m3/hm2 for grain machine harvest maize (planting density is 7.5×104 plants/hm2) in the arid and semi-arid areas in central and western Inner Mongolia.

Enhancing crop nitrogen use efficiency (NUE) in agricultural sciences is a pivotal challenge, particularly for high-demand crops like potatoes (Solanum tuberosum L.), the world's third most significant food crop. This study delves into the molecular responses of potatoes to low nitrogen (LN) stress, employing an integrative approach that combines transcriptomics and metabolomics to compare two cultivars with divergent NUE traits: XS6, known for its high NUE, and NS7, characterized by lower NUE. Our research unveils that XS6 exhibits higher chlorophyll and N content, increased tuber yield, and elevated N assimilation capacity under LN stress conditions compared to NS7. Through transcriptome analysis, we identified critical genes involved in C and N metabolism that had higher expression in XS6. A significant discovery was the high-affinity nitrate transporter 2.7 gene, which showed elevated expression in XS6, suggesting its key role in enhancing NUE. Metabolomics analysis further complemented these findings, revealing a sophisticated alteration of 1252 metabolites under LN stress, highlighting the dynamic interplay between carbon and N metabolism in coping with N scarcity. The integration of transcriptomic and metabolomic data underscored the crucial role of trehalose in mitigating N deficiency and enhancing NUE. This study provides novel insights into the molecular mechanisms governing NUE in potatoes, offering valuable perspectives for molecular breeding to enhance NUE in potatoes and potentially other crops. [ABSTRACT FROM AUTHOR]

Rotation fallow is an effective way to overcome the obstacles associated with continuous cropping, being beneficial for the growth and development of crops. Soil micro-organisms are closely related to soil fertility, plant productivity, soil pathogenic bacteria, and crop health in agricultural ecosystems. To explore the effects of different rotation fallow modes on the diversity and functions of the soil bacterial community, a study was conducted in an arid area in the western foothills of the Greater Khingan Mountains. Using spring wheat variety Longmai 36 as the research material, this study systematically analyzed the changes and functional differences in soil physicochemical and biological characteristics, as well as microbial communities (endosphere, rhizosphere, and bulk soil) in spring wheat fields under five rotation fallow modes: Wheat2016–Wheat2017–Wheat2018(WWW), Wheat2016–Rape2017–Fallow2018(WRF), Wheat2016–Potato2017–Fallow2018(WPF), Wheat2016–Fallow2017–Rape2018(WFR), and Wheat2016–Fallow2017–Potato2018 (WFP). The results indicate that, compared to WWW, the soil urease activity, microbial biomass nitrogen content, and microbial biomass phosphorus content were significantly increased in the WFP mode (p < 0.05). In particular, the soil moisture content, organic matter, and total potassium content were increased by 6.88%, 3.34%, and 25.57%, respectively. The Shannon index and chao1 index of bulk soil (BS) and rhizosphere (RS) bacteria were significantly higher than those of endosphere (ER) bacteria (p < 0.05). Both ecological niche and rotation fallow modes affected the relative abundance of dominant bacteria, and the relative abundance of beneficial bacteria, such as Bacteroidetes, Firmicutes, and Verrucomimicrobia, significantly increased in the rotation fallow modes. The complexity and stability of bacterial networks, and abundance of nitrogen-cycling-related functional taxa were significantly improved, while the abundance of pathogen-related functional taxa was significantly decreased. The differences in soil bacterial community structure were closely related to soil physicochemical properties. Compared to ER, BS and RS bacterial communities, which are more susceptible to soil physicochemical properties, and soil pH are key driving forces for bacterial community distribution. In summary, compared with continuous cropping, the rotation fallow mode is beneficial for conserving soil moisture and nutrients, stabilizing soil pH, (i.e., making the soil tend to be neutral), increasing the abundance of beneficial bacteria in the soil, enhancing the complexity and stability of microbial ecological networks, and increasing the abundance of nitrogen-cycling-related functional taxa, thus improving crop growth and development. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a crucial role in the response to global warming in terrestrial ecosystems. Soils with higher microbial diversity have more ecological functions, higher resistance to environmental stress and higher crop production capacity. At present, the research on the effect of temperature change on soil microorganisms mostly adopts the methods of outdoor infrared temperature measurement or exchange and transplantation of soil with different temperature zones. Here, we investigate how temperature gradients potentially affect soil bacterial communities to change. For this reason, we used indoor precise temperature control treatment and combined high-throughput sequencing with bioinformatics to systematically analyze the diversity and species composition of soil bacteria under different temperature gradients, and to clarify the variation trend and interaction relationships of different species with temperature gradients. The results showed that temperature significantly affected the Alpha diversity of soil bacterial communities (P

Global warming poses a serious threat to agriculture and natural systems, in part because of the change of soil moisture content, which changes soil microbial communities and ecological processes. Soil water content is the main factor limiting the growth of plants in soil. Microbial communities rely on soil water to complete their activities, and reveal the changes of underground microbial communities under different soil moisture content, which will help us to further understand the potential impact of climate change on soil ecosystem. To investigate the soil bacterial community structure, we established experiment indoor in the West foot of Daxing’an Mountains with manipulative water content treatments consisting of 20%, 15%, 10%, 5%, 0%. Results showed that bacterial community composition varied significantly with altered drought stress , but community richness did not. The relative abundance of Actinobacteria increased with the increase of drought stress, Proteobacteria, Acidobacteria and Gemmatimonadota decreased with the increase of drought stress, actinobacteria was more likely to accumulate or maintain stable under drought stress, bacterial communities can responding directly to changes in soil moisture.

Rhizosphere fungi play an important role in agricultural ecosystems. Their activities and interactions greatly affect various ecosystem processes related to nutrient cycling, soil borne diseases and crop health. The aim of this study was to investigate the effects of rotation fallow mode of spring wheat, potato, fallow and spring wheat, rape, fallow on rhizosphere fungi community structure and functional fungi composition of spring wheat. In this paper, high-throughput sequencing and bioinformatics were used to systematically analyze the diversity, composition and abundance of functional fungi in the rhizosphere of spring wheat at flowering stage. The results showed that: compared with WWW, rotation fallow mode could increase the diversity of rhizosphere fungi and eliminate a small number of specific fungi; The dominant phylum of spring wheat rhizosphere fungi were Ascomycota (32.72-47.99%), Basidiomycota (8.39-34.21%) and Mortierellomycota (2.05-18.42%). Rotation fallow mode significantly increased the relative abundance of Mortierellomycota and Chytridiomycota; The relative abundance of Basidiomycota decreased significantly (P

A controlled traffic no-till system is a cropping system that has a significant potential to improve soil health, sustainability and crop yield. A pilot experiment was conducted to compare soil chemical properties and crop yields between controlled traffic no-till and random traffic in an annual double-cropping area of the North China Plain from 2005 to 2010. The experiment was performed using three treatments: (1) controlled traffic no-till (NTCT); (2) random traffic no-till (NTRT); and (3) conventional tillage (CT). The NTCT treatment significantly improved soil organic matter and total N compared with both NTRT and CT treatments and remarkably increased available P compared with CT treatment in the surface soil layer (0-10 cm), but no significant differences were found in soil pH compared with both NTRT and CT treatments. However, in the 10-20- and 20-30-cm soil profiles, soil organic matter, total N and available P were reduced after NTCT treatment when compared with those obtained after CT treatment. At 0-10 cm soil depths, soil bulk density under NTCT and NTRT was higher than in CT, whereas the opposite was true at soil depths of 10-30 cm. Overall, it was found that the 6-year mean maize yield of NTCT and NTRT treatments was 10.9% and 1.1% higher respectively than the CT treatment, whereas the winter wheat yield was 1.1% and 3.0% higher respectively compared with the CT treatment. NTCT appears to be an improvement over current farming systems in an annual double-cropping area of the North China Plain. Additional keywords: available P, bulk density, C/N ratio, conventional tillage, pH, soil organic matter, total nitrogen. Received 29 August 2012, accepted 27 October 2015, published online 12 July 2016, Introduction Soil organic matter (SOM) represents the mineral and organic characteristics of soil (Alexandra and Jose 2005). It is also considered as a primary component of sustainable soil management and [...]