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Straw return is the simplest and the most economic method to improve soil structure. Slow decomposition rate limits straw return in sandy fields, which has becoming one of the obstacles in sandy land reclamation. Ammonification of straw before return accelerates straw decomposition, but it requires the use of extra N fertilizer, however, little is known about N fertilizer management in fields with ammoniated straw incorporation. So, a 3‐year field experiment was conducted with different proportions of N fertilizer aimed to maize straw ammonification and field broadcasting, and evaluated straw decomposition proportion, straw N release, soil organic carbon content, soil aggregates, soil water and N availability, and grain yield. Total N application rate was 300 kg per hectare, with five N input amounts for straw per hectare ammonification: 0 (SN0), 40 (SN40), 80 (SN80), 120 (SN120), and 160 (SN160) kg, and the rest of N broadcasted in soil during maize growing season. Ammonification accelerated straw decomposition and N release, and these effects showed no significant difference between SN80, SN120, and SN160. After straw decomposition for 150 days, the decomposition proportion was 62.1%, 53.0%, and 39.2% in SN80, SN40, and SN0, respectively. After 3 years of straw return, SN80 exhibited a significantly higher mean weight diameter of soil aggregates (35.6% higher), organic carbon content (18.4% higher), water‐holding capacity (17.4% higher), and soil water storage (17.2% higher) than SN0. Additionally, SN80 and SN120 showed the most significant effect on "N slow‐release" in soil. The above effects resulted with more available soil water and N used for crop growth, and increased grain yields (18.1% higher) and water use efficiency (18.6% higher) in SN80, compared with SN0. Hence, we conclude that a proper N allocation between straw and soil can synergistically enhance soil structure and crop productivity in sandy farmlands. This founding would provide scientific and technological support for straw return in sandy fields and is beneficial to sustainable development of oasis. [ABSTRACT FROM AUTHOR]

The growth status of mango (Mangifera indica L.) seedlings directly affects the yield and quality of mango, but there are few reports on water management at the growth stage of mango seedlings. The objective of this study was to identify an optimal water-saving irrigation method for mango seedlings. Taking surface drip irrigation as the control (CK), the effects of alternate infiltration irrigation (AII) on the photosynthetic characteristics, growth, and irrigation water use efficiency (IWUE) of mango seedlings were studied. The AII systems used three irrigation levels: 90% (AII90), 70% (AII70), and 50% (AII50) of the irrigation quota of CK. The results indicated that compared with CK, AII70 and AII50 increased the average leaf water use efficiency by 10.54% and 11.77%, respectively. However, compared with CK, AII50 decreased the average stomatal conductance and transpiration rate by 13.89% and 13.76%, respectively. There was a significant linear relationship between dry mass increment and net photosynthetic rate. The dynamic TOPSIS method indicated that AII70 provided optimal comprehensive photosynthetic benefits. The incremental dry mass and IWUE of AII70 were significantly higher than those of the other treatments. Therefore, we recommend applying a moderate water deficit through alternate infiltration irrigation (AII70) for water management in mango seedling cultivation. [ABSTRACT FROM AUTHOR]

Panax notoginseng cultivation planting conditions are harsh and require high soil moisture and slope of cultivated land, plus it takes 3–7 years from planting to harvesting. At present, the continuous crop barrier of Panax notoginseng has not been solved, which makes the arable land suitable for planting significantly reduced. And yet, there is almost no report on the impact of coupling water and slope on the growth of Panax notoginseng. Therefore, this study aims to explore the effects of different irrigation levels and slopes on soil water content (SWC) in the root zone, soil nutrient content, root characteristics, yield, water use efficiency (WUE), partial fertilizer productivity (PFP) and economic benefits of Panax notoginseng. During 2018–2020, a field experiment was conducted in the Panax notoginseng growing seasons with three irrigation levels (I 1 : 70–75% θ FC , I 2 : 75–80% θ FC , I 3 : 80–85% θ FC) and three slopes (S 1 : 2.43°, S 2 : 6.38°, S 3 : 16.38°). The results evidenced that soil water and nutrient content increased with increasing irrigation and decreased with increasing slope. The yield of Panax notoginseng , root morphological characteristics, WUE, PFP, and economic benefits showed a trend of increasing first and then decreasing with the increase of irrigation amount and slope, which increased with the increase of planting years. These parameters reached their maximum at the irrigation I 2 (75–80% θ FC) and slope S 2 (6.38°) treatments. Thus, based on the results of this study, medium irrigation I 2 (75–80% θ FC) and slope S 2 (6.38°) should be considered as the best slope and water management strategy to obtain both high Panax notoginseng yield and economic benefits. Through establishing a multi-objective optimization model with binary quadratic regression analysis. It was indicated that Panax notoginseng yield, WUE, PFP, and economic benefits simultaneously reached ≥ 98% of their maximum values when irrigation interval was 152–193 mm and slope interval was 5.4–9°. In summary, the results obtained in this study have important practical significance for the water management of Panax notoginseng cultivation in slope farmland in Yunnan Province, China. [Display omitted] • Water regulation technology for Panax notoginseng cultivation on sloping land was proposed. • Soil nutrient content and Soil water content gradually decreases with increasing slope. • I 2 S 2 treatment obtain maximum yield and economic efficiency. • Irrigation interval of 152-193 mm and slope interval of 5.4-9° determined to make yield, economic benefits, PFP and WUE reach ≥ 98% maximum. [ABSTRACT FROM AUTHOR]

Panax notoginseng (Burk) F. H. Chen, called Sanqi, is a valuable herbal plant and is widely used in Chinese medicine. However, the yield and saponin content cannot be guaranteed due to irrational irrigation and fertilizer management in low-latitude regions in southwestern China. To obtain suitable irrigation and organic fertilizer modes for improving the yield and saponin content of the plant, a shelter experiment was conducted using a randomized complete block design with a factorial arrangement of treatments with three replications. Three irrigation regimes, D L , D M and D S (irrigation upper/lower limit: 65–50% θ f , 50–35% θ f , and 35–20% θ f , respectively, where θ f is the field capacity), three organic fertilizer levels, F L , F M and F H (33, 48 and 63 t ha−1, respectively), and a control group, CK (65–50% θ f and 3 t ha−1), were applied in the two-year and eight-month growth cycles. With the paired comparison design, the results indicated that the flower dry yield, root dry yield and Panax notoginseng saponins (PNS) were significantly affected by different water deficit irrigation and organic fertilizer treatments, and they first increased and then decreased with increased water deficit or organic fertilizer. Compared with D L F H , D M F M reduced water use by 42.39% and fertilizer use by 23.81%, and the flower dry yield, root dry yield, PNS , water use efficiency and partial factor productivity of fertilizer increased by 19.67%, 22.52%, 54.33%, 149.72% and 91.83%, respectively. Under the D M F M treatment, the dry root yield and saponin content for 3-year-old P. notoginseng were 3039.19 kg ha−1 and 10.85%, respectively, which were higher than those resulting from other treatments. Additionally, the PNS resulting from D M F M exhibited the highest comprehensive score and comprehensive index based on principal component analysis and the TOPSIS model. This combination could create a higher yield of flowers and roots, provide a scientific management for planting, and improve the economic benefits for planters and the local government. • Study highlights role of deficit irrigation and organic fertilizer on Panax notoginseng growth. • Fertigation with highest irrigation and fertilizer amount increase root disease incidence and decrease root dry yield. • Severe drought stress significantly increased the water use efficiency for P. notoginseng. • Organic fertilizer schedule with water irrigation amount of 50~35% θf is proposed. [ABSTRACT FROM AUTHOR]

Cotton is the most widely planted fiber crop in the world and plays an important role in the national economy. Climate change alters the environmental elements of crop growth such as sunlight, moisture, and soil through changes in temperature and precipitation, which in turn affects the phenology period, growth potential, and cropping system of cotton, and ultimately affects yields. Studying the feedback of cotton growth to climate change is of great practical significance for cotton planting planning and yield increase and stabilization. Crop growth is affected by both climate and management measures, but most studies often ignore the impact of management measures, resulting in the inability to accurately assess the impact of climate. And existing research is mostly based on single sites or some provinces, lacking regional research on the main cotton producing areas in China. This study calibrated the AquaCrop model using data from 40 sites from three major cotton growing regions in China collected over different time periods between 1978 and 2018 and simulated the climate change impact on cotton for the subsequent years. The model showed good applicability in simulating the growth process of cotton in the study areas. The above-ground biomass (Bio), potential yield (Py) and water use efficiency (WUE) of cotton under the influence of climate change showed an increasing trend of 98% (39/40), 98%, and 93% of the sites, while the actual evapotranspiration (ET a) mainly decreased. Elevated CO 2 concentration increased cotton yield. The main climatic variables affecting cotton growth were wind speed, solar radiation, sunshine hours, and minimum and maximum temperature. Climate variables explained the changes in ET a , Bio , Py , and WUE by 65.1–95.5%, 9.7–74.5%, 14.8–68.3%, and 15.2–90.4%, respectively. Overall, cotton growth showed close relation to changes in W s , R s , T min , and T max. The study quantitatively analyzed and identified the main climatic factors affecting cotton growth and found that climate change and elevated CO 2 concentrations have a positive impact on cotton production. The simulations conducted in this study using multi-site data provided reliable regional information that can help develop future management strategies to maintain current and meet future demand for cotton in China, and provide recommendations and guidance for environmental regulation and sustainable discovery of the cotton growing process. [Display omitted] • The applicability of the AquaCrop model in the three major cotton producing regions in China was evaluated. • The effects of climate change on cotton growth and yield in china were analyzed under with unchanged management measures. • Cotton growth and yield changes under constant and elevated CO 2 concentration scenarios were comparatively analyzed. [ABSTRACT FROM AUTHOR]

It is still a long-term challenge to decrease root rot and improve saponin content of Panax notoginseng , thus economic benefits in Guangxi and Yunnan provinces, China. The objective of this study was therefore to propose a promising abiotic stresses strategy: deficit irrigation combined with sodium chloride (DISC) to cope with the challenge. A two-year field experiment was conducted to explore the effects of deficit irrigation combined with sodium chloride on physiological traits, yield, quality attributes, water use efficiency, and economic benefit of Panax notoginseng in 2018 and 2019. Experiment treatments consisted of two deficit irrigation levels [ D L , light deficit level: irrigation upper∼lower limit (80–65 %) θ FC ; D M , moderate deficit level: irrigation upper∼lower limit: (70–55 %) θ FC , where θ FC represents field capacity] and five NaCl application rates [0 (C 0), 15 (C 1), 30 (C 2), 45 (C 3), and 60 (C 4) mmol L−1], respectively. All treatments were designed using a randomized complete block with three replications. The results indicated that DISC could significantly promote the physiology and growth of Panax notoginseng and improve yield, quality and economic benefits under micro-sprinkler irrigation and shaded conditions in 2018 and 2019. Compared with the D M C 0 and D L C 0 treatments, D L C 1 treatment significantly improved net photosynthetic rate (Pn), stomatal conductance (Gs), root (k r), shoot (k sh), and canopy (k c) hydraulic conductance of Panax notoginseng. The D L C 1 treatment significantly increased root length, surface area, average diameter, and volume of root of Panax notoginseng compared with the D M C 0 and D L C 0 treatments. The D L C 1 treatment significantly improved rood dry matter, yield, saponin content of Panax notoginseng , water use efficiency, and economic benefits by decreasing the incidence of root rot, but reverse results were observed in the D L C 2 , D L C 3 , and D L C 4 treatments. Therefore, this study suggested that deficit irrigation amount [ D L , (80–65 %) θ FC ] combined with NaCl concentration (C 1 , 15 mmol L−1) should be recommended as an appropriate agronomic management strategy to alleviate root rot and improve water use efficiency, saponin content, economic benefits of Panax notoginseng in the seasonally arid region of Southwest China. [Display omitted] • Deficit irrigation combined with sodium chloride (DISC): a strategy to improve Panax notoginseng production. • The DISC decreased root rot and improved physiological features of plant. • The DISC improved yield, quality, and economic benefits of Panax notoginseng. • The DISC [ D L , (80–65 %) θ FC and C 1 , (15 mmol L−1)] should be recommended to promote production of Panax notoginseng. [ABSTRACT FROM AUTHOR]

Excessive water and fertilizer management strategy was main factor restricting high-quality production of edible Rose s. The objective of this study was therefore to explore a combination of micro-irrigation method and bio-organic fertilizer application amount suitable for high-quality production of edible Rose s. A two-year greenhouse experiment was conducted to investigate the effects micro-irrigation method and bio-organic fertilizer application on soil environment, photosynthetic characteristics, yield, and nutritional quality of edible Rose in 2019 and 2020. The experiment treatments consisted of three micro-irrigation methods [micro-sprinkler irrigation (SI), drip irrigation (DI), and micro-moistening irrigation (MI)] and four bio-organic fertilizer supplementation levels (0, 5000, 10000, and 15000 kg ha−1, labeled as BF 0 , BF L , BF M , and BF H). The results indicated that MIBF M significantly improved soil water content, soil organic matter, pH, and the number of bacteria, fungus, and actinomycetes in the edible Rose field among all treatments. The MIBF M could improve net photosynthetic rate and leaf instantaneous water use efficiency of edible Rose compared with MIBF H. The flower weight, average flower diameter, and edible Rose yield were larger in MIBF M than those of MIBF H in 2019 and 2020. The MIBF M improved total sugar, flavonoids, vitamin C, and total amino acids of edible Rose compared with MIBF H. According to analyzing the relationships between photosynthesis, soil environment, flower yield, and quality among all treatments, we found MIBF M promoted edible Rose production by improving soil environment. The membership function method was used to comprehensively evaluate the nutritional quality of edible Rose s, we recommended that the combination of micro-moistening irrigation (MI) combined with bio-organic fertilizer application amount (10000 kg ha−1) (BF M) would be an adaptive irrigation and fertilization management strategy for improving soil environment and edible Rose production in Southwest China. • The MIBF M could improve soil environment and edible Rose productivity. • The MIBF M improved soil water storage, soil nutrients and soil microorganism. • The MIBF M improved yield and nutritional quality of edible Rose. [ABSTRACT FROM AUTHOR]

Mango (Mangifera indica L.) is one of the widely grown fruit crops and brings remarkable economic benefit in the xerothermic regions of southwest China. However, mango yield and quality can not be guaranteed due to the severe seasonal drought, low precipitation and extensive management of water and fertilizer. To investigate the effects of irrigation amount and fertilizer regime on mango yield, fruit quality, water use efficiency (WUE) and partial fertilizer productivity (PFP), an orthogonal experiment [L 9 (3)4] was conducted on mango under drip fertigation during 2018–2019. The four factors were irrigation amount (IA) and fertilization rate at the flowering (F Ⅰ), fruit expansion (F Ⅱ) and fruit ripening (F Ⅲ) growth stages. There were three irrigation amounts, i.e., full irrigation (FI: 100%ET c), mild deficit irrigation (DI M : 75%ET c) and severe deficit irrigation (DI S : 50%ET c), and three fertilization rates, i.e., 75 (F 75), 50 (F 50) and 25 (F 25) kg ha−1 using a compound water-soluble fertilizer (N:P 2 O 5 :K 2 O=20%:20%:20%). The results showed the order of factors influencing fruit yield and WUE in terms of their importance was IA, F Ⅱ , F Ⅰ and F Ⅲ , that influencing water, vitamin C and carotenoid contents in fruit was IA, F Ⅲ , F Ⅱ and F Ⅰ , and that influencing soluble solids and total sugar contents was IA, F Ⅲ , F Ⅰ and F Ⅱ. The WUE of DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 was highest. FIF Ⅰ25 F Ⅱ75 F Ⅲ50 achieved the highest fruit yield, PFP and contents of soluble solid, vitamin C and carotenoid. DI M F Ⅰ25 F Ⅱ50 F Ⅲ75 had the highest total sugar content and the lowest titratable acid content. Based on the comprehensive scoring method, DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 achieved the optimum score in terms of fruit yield and water–fertilizer use efficiency, while FIF Ⅰ25 F Ⅱ75 F Ⅲ50 was optimum for fruit quality. Further, the TOPSIS method indicated DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 had the optimal comprehensive benefit. To obtain high yield, quality and water–fertilizer use efficiency, the recommended water and fertilizer scheduling was irrigation with 75% ET c and fertilization with 50, 75 and 25 kg ha−1 at the flowering, fruit expansion and fruit ripening stages, respectively. The research results provided a scientific reference for identified optimum combination irrigation and fertilizer in the xerothermic environment of southwest China. • Fruit yield, WUE, PFP and quality were more sensitive to irrigation than staged fertilization. • Increasing fertilizer allocation at fruit expansion stage, FI elevated fruit yield and PFP, while DI M increased WUE. • Improving fertilizer allocation at the later growth, FI increased SS, VC and CC, while DI M increased TS. • Optimal strategy of irrigation and split fertilization for mango was revealed. [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]