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Abstract: A pot experiment was conducted to investigate the effect of three drip irrigation methods (i.e. conventional drip irrigation (CDI), both sides of the root-zone irrigated with full watering, alternate drip irrigation (ADI), both sides of the root-zone irrigated alternatively with half of the full watering, and fixed drip irrigation (FDI), only one side of the root-zone irrigated with half of the full watering) on growth, physiology, root hydraulic conductance and water use of young apple tree under different nitrogen (N) or phosphorus (P) fertilization (i.e. CK (no fertilization), N1 (0.2gN/kg), N2 (0.4gN/kg), P1 (0.2gP2O5/kg) and P2 (0.4gP2O5/kg)). Results show that compared to CDI, ADI and FDI reduced mean root dry mass, daily transpiration, root hydraulic conductance (K r ), leaf photosynthesis rate, transpiration rate and stomatal conductance of young apple tree by 6.9 and 27.7, 29.3 and 45.0, 6.8 and 37.9, 2.5 and 4.8, 32.6 and 33.0, 22.1 and 22.3%, but increased leaf water use efficiency (WUE) by 31.3 and 29.8%, respectively when they saved irrigation water by 50%. Compared to the CK, N or P fertilization significantly increased K r , and K r was increased with the increased N or P fertilization level. There were parabolic correlations between K r and root dry mass, daily transpiration and stomatal conductance. Our results indicate that ADI reduced transpiration rate significantly, but it did not reduce photosynthesis rate and K r significantly, thus alternate drip irrigation improved WUE and the regulation ability of water balance in plants. [Copyright &y& Elsevier]

• Water, N and year significantly affect dry matter accumulation, fruit yield, quality, water and N productivity. • The Entropy Weight-TOPSIS method was adopted to achieve the multi-objective optimization of water and N fertilizer. • I80N360 (80% ET 0 - 360 kg N ha−1) is the ideal water and N management strategy for greenhouse cherry tomato. In the context of climate-change and shortage of fresh water resources, improving agricultural productivity has become a major challenge globally, especially in China with large population. In this study, the purpose was to achieve the optimal combination of water and nitrogen (N) rates for greenhouse cherry tomato based on fruit yield, quality, net income and water-N productivity. Herein, during 2019–2021, three irrigation levels (I100: 100% ET 0 ; I80: 80% ET 0 ; I60: 60% ET 0 , where ET 0 was the reference evapotranspiration) and five N rates (450, 360, 270, 180 and 0 kg N ha−1, defined by N450, N360, N270, N180 and N0, respectively) with 15 treatments were set up. The 3-year ANOVA analysis indicated that irrigation, N fertilizer and year had significant effects on dry matter accumulation, fruit yield, quality, water and N productivity of greenhouse cherry tomato. Both the highest fruit yield (56.72 t ha−1, average of 3-year) and net income (60.8 × 104 CNY ha−1) were occurred under I80N360 treatment, though peak N partial factor productivity (PFPN, 294.88 kg−1) was observed under I80N180 treatment. The combined application of water and N fertilizer increased water productivity (WP) by 15.64% (average of 3-year) compared to I60N0 treatment, with I80N360 and I60N270 treatments having the highest WP. N fertilizer addition significantly increased fruit yield and WP irrespective of irrigation level, but the differences between N360 and N450 treatments were not significant in 80% ET 0 and 100% ET 0 irrigation level treatments, and between N270, N360 and N450 treatments in 60% ET 0 irrigation level treatments. Nevertheless, PFPN decreased significantly as the N rate increased. In addition, fruit quality could be improved at some extent under deficit irrigation relative to full irrigation regardless of N rate. More specifically, compared with the full irrigation treatment (I100), the I80 treatment increased the content of total soluble solid (TSS) by an average of 6.68%, soluble sugar (SS) by 11.96%, organic acid (OA) by 4.91%, sugar acid ratio (SAR) by 11.28%, vitamin C (VC) by 14.55%, lycopene by 30.06% and firmness by 7.60%; meanwhile, the I60 treatment increased TSS by an average of 11.17%, SS by 18.60%, OA by 12.04%, SAR by 10.02%, VC by 27.55%, lycopene by -7.93% and firmness by 13.14%, respectively. The increase of N rate largely increased TSS, SS, SAR, VC and lycopene, while these indicators decreased when N rate exceeded a threshold. Nevertheless, OA and firmness increased with increasing N rate, while firmness showed a slight decrease when N rate increased from N360 to N450 treatment. Generally, in a greenhouse cherry tomato production agroecosystem, the optimal amount of N fertilizer applied for each indicator varies with the availability of irrigation water. Furthermore, the Entropy-Weight TOPSIS method was adopted and the results indicated that the optimization of irrigation and N fertilizer supply schedule (I80N360 treatment: 80% ET 0 –360 kg N ha−1) was conducive to increase fruit yield, net income and water-N productivity whilst maintaining fruit quality in greenhouse cherry tomato cultivation. [ABSTRACT FROM AUTHOR]

• Reasonable irrigation and fertilization strategies significantly improved the nutrient content, bacterial diversity, and community abundance of Panax notoginseng soil. • The relationships among soil physical and chemical properties, bacterial diversity, community structure and community function were elucidated. • W2F4 treatment significantly improved soil physicochemical properties, bacterial diversity, community structure and community function, and was the optimal irrigation fertilization strategy. Improper irrigation and fertilization can result in soil compaction, solidification, and acidification, consequently disrupting the equilibrium of the soil microbial community. The objective was to enhance the microbial environment in Panax notoginseng soil, augment bacterial diversity, increase community abundance, and establish a scientific and theoretical foundation for Panax notoginseng cultivation. Panax notoginseng field planting experiment was carried out from 2019 to 2021, involving two controlled variables: irrigation (W) and fertilizer application (F). Three irrigation levels were established, denoted as W1 (0.6 FC), W2 (0.75 FC), and W3 (0.9 FC). A total of 1440 kg•hm−2 of soluble organic fertilizer was applied throughout the entire growth cycle, with varying proportions allocated to each growth stage. Four fertilization levels were designated as F1 (rooting stage: seedling stage: flowering stage: fruiting stage = 25 %: 25 %: 25 %: 25 %), F2 (20 %: 25 %: 30 %: 25 %), F3 (15 %: 30 %: 30 %: 25 %), and F4 (10 %: 40 %: 20 %: 30 %), total 12 treatments. Non-irrigated and non-fertilized CK treatments were employed as control. Soil physicochemical attributes, bacterial diversity, community structure, and functional characteristics across various water and fertilizer treatments were comprehensively assessed utilizing the quotient-weighted TOPSIS method. The results showed that coupled irrigation and fertilization treatments had a significant impact on various soil parameters of Panax notoginseng, including total nitrogen, nitrate nitrogen, ammonium nitrogen, organic carbon, pH, water content, and bacterial alpha diversity (P < 0.05). Moreover, coupled irrigation and fertilization treatments had a highly significant influence on soil water content during the rooting stage, seedling stage, and fruiting stage (P < 0.01). Total nitrogen, nitrate nitrogen, ammonium nitrogen, water content, and pH emerged as the primary environmental factors significantly shaping the structure of the soil bacterial community. In the W2F4 treatment, soil total nitrogen, organic carbon content, pH, Chao1, Shannon index, and functional abundance in categories such as chemoheterotrophy, aerobic chemoheterotrophy, nitrogen fixation, nitrate reduction, nitrogen respiration, and nitrate respiration were notably higher compared to other water-fertilized treatments. Furthermore, the W2F4 treatment ranked first in the TOPSIS comprehensive evaluation. Consequently, the W2F4 treatment emerged as the optimal irrigation-fertilization strategy for enhancing soil microbial activity and fertility in Panax notoginseng cultivation. This study establishes a theoretical foundation for enhancing the microbiological environment of Panax notoginseng soils, augmenting soil bacterial diversity, increasing community abundance, and ultimately elevating soil fertility for the efficient and high-quality cultivation of Panax notoginseng. [ABSTRACT FROM AUTHOR]

• Entropy weight method was used to determine the best water saving method for mango. • Sugarcane leaf mulching was significantly increased fruit yield and IWUE. • Sugarcane leaf mulching decreased the titratable acid by 31.3%. • Sugarcane leaf mulching with 50% ETC had the best fresh fruit quality. Rational application of field-management technology can not only improve mango (Mangifera indica L.) fresh fruit yield and quality but also improve irrigation water use efficiency (IWUE). However, few studies have involved the simultaneous use of mulch and irrigation-management techniques in hot and dry environments to achieve a relatively good level of performance. We used the entropy weight method (EWM) to explore an optimal mulching and irrigation-management technology for mango production in a dry hot environment. Three irrigation levels [FI, 100% mango evapotranspiration (ET C); DI 75 , 75% ET C ; DI 50 , 50% ET C ] were designed with (SM) and without (NM) sugarcane leaf mulching in 2018 and 2019 in a dry hot environment. The results showed that the photosynthetic rate, stomatal conductance, transpiration rate, leaf water-use efficiency, and carboxylation efficiency in the SM treatment were 12.5% to 83.7% higher than those in the NM treatment in both years. Compared with the NM treatment, the SM treatment increased the fresh fruit yield and IWUE by 45.7% and 49.7% in 2018 and by 46.1% and 63.2% in 2019. The solid-to-acid ratio and sugar-to-acid ratio in the SM treatment were 48.5% and 50.4% higher than those in the NM treatment, respectively, but the titratable acid content decreased by 31.3%. Compared with FI, DI 75 increased carotenoid content, total soluble solids, solid-to-acid ratio and sugar-to-acid ratio by 8.4%–40.7%, while it reduced titratable acid by 22.8%. Compared with FI, DI 50 reduced fresh fruit yield by 24.3% and 21.9% in 2018 and 2019, respectively, while it increased IWUE by 13.6% and 17.7%. The fresh fruit yield of SMDI 75 was the highest, which was 1.42 and 1.44 times that of NMFI in both years, respectively. A comprehensive evaluation by EWM also showed that the SMDI 50 treatment had the highest comprehensive scores of mango yield, quality and water-use efficiency, which could provide a basis for the scientific management of mango fertiliser in dry and hot areas of China. [ABSTRACT FROM AUTHOR]

• Micro-moistening irrigation (MM) significantly increased dry mass (DM) accumulation and water-fertilizer use efficiency of young mango tree. • Moderate fertilization rate (F M) had the highest leaf net photosynthetic rate (P n), hydraulic conductivity and healthy index (H i). • MMF M treatment was the suitable coupling mode of irrigation and fertilization management for young mango tree. Unsuitable irrigation and soil nutrient deficiency affect the normal physiology and growth of mango (Mangifera indica L.) of tropical fruit tree in Southwest China. To obtain optimal fertigation mode for mango, the effects of three micro-irrigation methods (i.e., micro-sprinkler irrigation (SI), drip irrigation (DI) and micro-moistening irrigation (MM)) on photosynthetic characteristics, hydraulic conductivity, growth and water-fertilizer use efficiency of young mango tree were investigated under four fertilization rates (i.e., 0 g plant−1 (F N), 9.3 g plant−1 (F L), 18.6 g plant−1 (F M) and 27.9 g plant−1 (F H), a compound water-soluble fertilizer) using a randomized block design experiment. The results indicated that DI and MM increased net photosynthetic rate (P n) by 17.50 and 28.95%, root hydraulic conductivity (K r) by 39.65 and 52.69%, shoot hydraulic conductivity (K sh) by 48.63 and 82.38%, total dry mass (DM) by 27.44 and 47.13%, water use efficiency (WUE ET) by 43.27 and 73.17%, fertilizer agronomic efficiency (FAE) by 45.92 and 95.41%, and partial factor productivity of fertilizer (PFP) by 33.96 and 54.44%, but reduced transpiration rate (T r) by 6.61 and 16.38%, leaf with petiole hydraulic conductivity (K l+p) by 13.11 and 30.32%, and water consumption (ET) by 10.38 and 14.85% when compared with SI. Compared with F N , enhancing fertilization rate significantly increased P n , T r , total hydraulic conductivity (root to leaf), total DM , healthy index (H i) and WUE ET , and their maximum values appeared in the F M. FAE firstly increased and then decreased, while PFP gradually reduced with the increase of fertilization rate. MMF M had the highest total DM and WUE ET , 2.32 and 2.58 times of SIF N (CK), and the largest FAE of 4.95 kg−1. Thus, MMF M (micro-moistening irrigation with moderate fertilization rate of 18.6 g plant−1) significantly promoted growth and improved water-fertilizer use efficiency of young mango tree, which was the best coupling mode of irrigation method and fertilization rate. [ABSTRACT FROM AUTHOR]