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【Objective】 Drip irrigation combined with fertilization has become a standard practice in grape production in Xinjiang, China. The purpose of this paper is to study the effect of different combinations of irrigation and fertigation on growth and fruit yield and quality of grape. 【Method】 The experiment conducted in a vineyard; it compared three irrigation amounts: 10 950 m3/hm2 (W1), 9 150 m3/hm2 (W2) and 7 800 m3/hm2 (W3), and three fertilizations: 750 kg/hm2 (N1), 450 kg/hm2 (N2) and 300 kg/hm2 (N3). Each treatment had three replicas arranged randomly in the field. In each treatment, we measured the growth, traits of fruit yield and quality. 【Result】 Rational combination of irrigation and fertilization improved fruit appearance, 100-fruit weight, and fruit yield and quality. Among all treatments, W2+N2 was optimal in improving fruit appearance, 100-grain weight, fruit yield, soluble solids and hardness of the grape, but less than W2+N3 in increasing the solid-acid ratio in the grape despite the insignificant difference between them. W1+N1 was most effective in increasing vitamin C, and the difference from other treatments was significant. 【Conclusion】 Experimental data obtained from all treatments showed that irrigating the grape by 9 150 m3/hm2 of water combined with 450 kg/hm2 of nitrogen fertilization was optimal. Further analysis of the experimental data using the binary quadratic regression optimization model showed that the optimal fertigation can be further fine-tuned to irrigation amount of 9 723 m3/hm2 and fertilization of 557 kg/hm2, which increases the fruit yield to 38 636.53 kg/hm2.

【Objective】 In order to explore the management mode of water, fertilizer and salt under mulched saline water drip irrigation in southern Xinjiang. 【Method】 Freshwater and saline water were mixed at volumetric ratio of 1∶0, 4∶1 and 2∶3, respectively, for irrigation. For each irrigation treatment, there were three nitrogen applications: 400 kg/hm2 (over applied), 300 kg/hm2 (used by local farmers) and 200 kg/hm2. Freshwater irrigation combined with 300 kg/hm2 of N fertilization was taken as the control. During the experiment, we measured the uptake of ions and nutrients by the crop, as well as dry matter distribution and accumulation 【Result】 With the increase in irrigation water salinity, the amounts of ions (Na+, Cl- and Ca2+) taken up by the cotton increased, especially Na+ and Cl- . Most of these ions were found in leaves, followed by stems. Increasing irrigation water salinity reduced the uptake of N, P and K, while increasing nitrogen fertilization promoted dry matter accumulation in the roots and uptake of nutrients and ions, thereby boosting plant growth. It was found that increasing nitrogen fertilization enhanced absorption of Na+ and Cl- by the cotton. A moderate accumulation of Na+ and Cl- in stems and leaves associated with 4∶1 of freshwater and saline water suppressed vegetative growth and distributed more nutrients to the buds and bolls, thereby leading to a yield increase. However, over-adsorption of Na+ and Cl- by the crop due to the increase in portion of the saline water could inhibit nutrient uptake and its translocation to the reproductive organs, leading to a yield reduction. Compared with CK, mixing freshwater and saline water at 4∶1 ratio combined with high nitrogen fertilization increased dry matter accumulation by 1.5% without compromising yield (6 829.80 kg/hm2). 【Conclusion】 Mixing freshwater and saline water at 4∶1 combined with an increase in nitrogen fertilization can promote uptake of ions and nutrients by the crop, as well as translation of dry matter to reproductive organs, without compromising cotton yield. It can thus be used as a guidance for cotton production in southern Xinjiang, China.

Introduction: In arid areas, exploring new "dry sowing wet emergence (DSWE)" water-saving irrigation techniques may become one of the most important ways to reduce agricultural irrigation water use and improve economic efficiency. Methods: The study was conducted in a two-year field trial in 2021 and 2022, setting up three seedling emergence rates (W1: 6 mm, W2: 10.5 mm, W3: 15 mm) and two drip frequencies (D1: 2 times, D2: 4 times) for a total of six irrigation combinations. Results and discussion: The results indicate that under the "DSWE" irrigation pattern, in contrast to the low frequency treatment, the photosynthetic efficiency of cotton leaves in the high-frequency treatment is significantly higher. The stomatal conductance of cotton leaves has increased by 6.67% within two years, and the net photosynthetic rate has risen by 12.22%. Compared with the CK treatment, there is no remarkable difference in the photosynthetic indicators of the W3D2 treatment, while the net photosynthetic rate has increased by 1.68%. The population physiological indicators of each treatment group exhibit a trend of initially increasing and then decreasing as the growth period prolongs. The differences in the group population physiological indicators of cotton at the seedling stage among different seedling water treatments are relatively minor. The high frequency treatment maintains a relatively high level throughout the growth period. Compared with the low-frequency treatment, the yields of lint cotton and seed cotton in the high-frequency treatment have increased by 14.77% and 20.89%, respectively. Compared with the winter irrigation technology, there are no significant differences in the cotton yield and quality indicators of the "DSWE" high-frequency and high-seedling water treatment (W3D2). Over two years, the average unit yields of lint and seed cotton have decreased by 1.95% and 3.01%, respectively. Nevertheless, irrigation water during the growth period declined by 38.46%. The appropriate "DSWE" irrigation technology (W3D2) can significantly enhance the physiological indicators of cotton, ensuring crop yield and quality while significantly reducing the amount of agricultural irrigation water. [ABSTRACT FROM AUTHOR]

The lack of trace element iron has become a key factor restricting vegetable yield and quality improvement. To address the low production efficiency of water–fertilizer coupling in agricultural production, we used a combination of experimental research, theoretical analysis, and mathematical modeling to systematically determine the effects of magneto-electric water irrigation with iron application on spinach growth and physiology, its yield and quality, and soil water transport characteristics. Compared with conventional water irrigation, under magneto-electric water irrigation, the water volume and applied iron concentration average increased the total accumulation of nitrogen, carbon, and iron in the aboveground part of spinach by 3.71%, 10.16%, and 14.14%, respectively, and the aboveground part of spinach had the highest total accumulation of nitrogen and carbon when irrigation water was 3300 m3 ha−1 and iron fertilizer application at 0.15%. Additionally, magneto-electric water irrigation increased spinach aboveground fresh weight and soluble sugar and protein content by an average of 13.34, 18.26, and 11.61%, respectively. Based on a comprehensive quantitative evaluation and analysis of aboveground nutrient accumulation in spinach, aboveground fresh weight, water use efficiency, and soluble sugar and protein content, we determined the optimal irrigation water and iron fertilizer application for spinach growth. [ABSTRACT FROM AUTHOR]

The problem of poor water and fertilizer retention in sandy soils can lead to physiological growth restriction and yield and quality decline in apples. Sodium carboxymethyl cellulose (CMC) formula can improve the soil structure and increase the water- and fertilizer-holding capacity of the soil, and Biogenic Stimulant (BS) can improve the drought stress resistance of crops and promote the physiological growth of crops. Considering that CMC and BS may improve the physiological characteristics of sandy soil apples, in this study, CMC was coupled with BS in sandy apples, and the effects on the physiological characteristics, yield, and quality of apples were systematically investigated. The results showed that CMC and BS could increase leaf N, P, and K content, with the greatest increases seen in the Y2C2 treatment (9.28, 0.61, and 0.56 g kg−1, respectively) compared with the CK treatment. The SPAD values of leaves following the coupled CMC and BS treatment compared to the CK treatment were elevated in the range of 4.47–24.29% at the flowering and fruiting stage, 2.84–26.50% at fruit expansion stage, and 6.64–19.41% at maturation stage. In the light response data of different treatments, the maximum net photosynthetic rate occurred in the Y2C2 treatment, and the net photosynthetic rate, transpiration rate, and stomatal conductance were all the highest in the Y2C2 treatment during the fruit expansion stage, with the net photosynthetic rate being higher than that of the CK treatment by 5.09 µmol m−2 s−1. The combination treatments of CMC and BS increased apple yield by 10.69 to 27.62% as compared to the CK treatment, and also increased soluble reducing sugar, soluble solids, and VC and reduced the titratable acid content. There was no correlation between the SPAD value during fruit expansion (p > 0.05) and the other physiological indexes (p < 0.05). Through the established functional relationship between the application rate of CMC and BS and apple yield, the recommended BS application rate of 27 kg ha−1 and CMC application rate of 20.625 kg ha−1 could yield up to 43,357.8 kg ha−1. [ABSTRACT FROM AUTHOR]

In this study, willow catkins/MoS2 nanoparticles (denoted as WCMSs) have been prepared using a hydrothermal method. The WCMSs were modified with oleic acid (OA) to improve dispersion in base oil. The friction and wear properties of WCMSs in liquid paraffin (LP) for steel balls were investigated using a four-ball wear tester. The results have shown that at a high reaction temperature, willow catkins (being used as a template) and urea (being used as a nitrogen resource) can effectively decrease the wear scar diameters (WSDs) and coefficients of friction (COFs). At a concentration of 0.5 wt.%, the WSD and COF of steel balls, when lubricated using LP containing modified WCMS with urea, decreased from 0.65 mm and 0.175 of pure LP to 0.46 mm and 0.09, respectively. The addition of urea and hydroxylated catkins can generate a significant number of loose nano-sheets and even graphene-like sheets. The weak van der Waals forces, decreasing the shear forces that the steel balls must overcome, provide effective lubrication during rotation. On the other hand, the tribo-films containing MoS2, FeS, azide, metal oxides and other compounds play important roles in reducing friction and facilitating anti-wear properties. [ABSTRACT FROM AUTHOR]

To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control, three different emergence water volumes（60, 105, and 150 m³/hm²）, two different frequencies（high frequency and low frequency） and one double film cover winter irrigation control treatment（CK: 2 250 m³/hm²） were set up to analyze the spatial distribution patterns of soil water and salt environment and root density in dry sown and wet emerged cotton fields under diffe-rent moisture control conditions. The results show that the soil water content and water infiltration range gradually become larger with the increase of seedling water quantity, and the larger the seedling water quantity, the higher the soil water content. With the same seedling water quantity, the soil water content of the high-frequency（HF） treatment becomes obviously larger. The soil conductivity of each treatment tends to decrease gradually with the increase of seedling water and drip frequency, among which the distribution of soil conductivity of S6 treatment is closest to that of CK. With the increase in soil depth, the soil conductivity tends to increase first and then decrease. Compared with the low-frequency（LF） treatment, the high-frequency treatment shows a significantly deeper soil salt accumulation layer. The root length density（RLD） of cotton gradually increases with the amount of seedling water and the frequency of dripping. The soil layer of root distribution gradually deepens with the amount of seedling water in the vertical direction, and the RLD value in the horizontal direction is significantly greater in the mulched area than that in the bare area between films. This research can serve as a solid scientific foundation for the use of dry sowing and wet emergence techniques in cotton fields in southern Xinjiang. [ABSTRACT FROM AUTHOR]