Irrigation Conditions Research Articles

Evaluating Water Stress Adaptation in Cotton: Multivariate Analysis in F6–F7 Generations for Yield, Fibre Quality and Variety Selection

AbstractThe impact of drought stress on productivity of cotton (Gossypium hirsutum L.) is a well‐known challenge in agricultural production, and concurrently, the question of whether using the same or different selection criteria in well‐watered and water‐deficit conditions to select drought‐tolerant cotton varieties remains unclear. This study aimed to comprehensively assess the single plant progeny lines within the F6 and F7 generations for determine response to DS and select the tolerant lines within the F7 generation. Single plant progeny rows were established, with the deficit water condition comprising 108 and 136 single plants for the F6 and F7 generations, respectively, and the WW condition consisting of 120 and 156 single plants for the F6 and F7 generations, respectively, with four blocks in Augmented experimental design. These progeny rows have length of 12 m, incorporate five control varieties (Karizma, Gloria, Carla, Candia and Claudia) to facilitate a comprehensive comparison. The study findings showed that fibre length, boll number and lint percentage were identified as the most crucial selection criteria under both WW and deficit irrigation conditions through principal component analysis. These indicators are highly beneficial for evaluating cotton's drought tolerance and screening potential drought‐tolerant lines under both irrigation scenarios. According to the decision tree analysis, FL and BN have emerged as the most critical decision‐making parameter in both irrigation conditions. Furthermore, the analysis revealed that each selection criterion has different impact in the comprehensive selection process. Also, as a result of all statistical analysis results and breeder observations, a total of 10 cotton lines were selected in the F7 generation. These selected genotypes hold promise for future cotton breeding programmes, providing an avenue to enhance drought tolerance and elevate cotton yield and productivity.Clinical Trial Registration: This study does not involve a clinical trial, and therefore, clinical trial registration is not applicable.

Assessing the climate adaptive potential of imported Chili in comparison with local cultivars through germination performance analysis

BackgroundThe study offers insightful information about the adaptability of local and imported Chili cultivars. This experiment examines how three different chili cultivars Tanjung, Unpad, and Osaka perform in the germination and early growth phases while considering a wide range of environmental conditions. Research conducted in Jatinangor, Sumedang Regency, Indonesia, highlights the differences between cultivars and the varied possibilities for adaptability each variation possesses.ResultsAmong them, Tanjung stands out as the most promising cultivar; its robust performance is demonstrated by its high germination index 91.7. Notable features of Osaka include the highest biomass output (1.429 g), the best water usage efficiency (WUE) at 0.015 g/liter, and the best distribution uniformity (91.2%) and application efficiency (73.6%) under different irrigation conditions. Tanjung’s competitiveness is further evidenced by the fact that it trails Osaka closely on several metrics. Lower performance across criteria for Unpad suggests possible issues with flexibility.ConclusionThe value of this information becomes apparent when it comes to well-informed breeding programs and cultivation techniques, especially considering uncertain climate patterns and global climate change. This research contributes significantly to the body of knowledge, enabling well-informed choices for environmentally dynamic, sustainable chili farming.

Adaptation strategies for cumin in Sabzevar, Iran: planting date and irrigation management

ABSTRACT The current study aimed to investigate the effect of planting date and irrigation on some characteristics of cumin cultivated in Iran. The experimental characteristics included three planting dates and five irrigation regimes. Irrigation at flowering + seed filling stage and full irrigation had the highest essential oil content (3.6%) and plant height (16.71 cm), respectively. On all planting dates, irrigation enhanced the total chlorophyll and carotenoids content, relative water content, umbel number plant−1, seed number umbel−1, 1,000-seed weight, and seed yield but reduced the proline content and water-use efficiency (WUE). The highest chlorophyll content (1.54 mg g−1 fresh weight (FW)), carotenoids content (0.35 mg g−1 FW), umbel number plant−1 (18.03), seed number umbel−1 (21.16), 1,000-seed weight (4.12 g), seed yield (1002.7 kg ha−1), and essential oil yield (22.13 kg ha−1) were obtained on 19 January and irrigation at the flowering + seed filling stages. The greatest amount of WUE (0.53 kg m−3) was measured on 9 January under no irrigation condition. Therefore, to produce cumin under similar climatic conditions, early planting of cumin in early January, along with two irrigations at the flowering and seed filling stages, is recommended.

Global Bibliometric Analysis of Research on the Application of Unconventional Water in Agricultural Irrigation

The development and utilization of unconventional water resources has become a strategy to alleviate the agricultural water crisis in many countries and regions. To understand the research progress, hot spots, and future trends in the field of unconventional water agricultural irrigation (UWAI), this paper systematically analyzes 6738 publications based on the core database of Web of Science 1990–2023 using the scientific bibliometric analysis software CiteSpace, VOSviewer, and Scimago Graphica. The results showed that the research on UWAI is always rapidly developing. Soil science, crop science, and bioengineering are the main disciplines involved. Most research on WUAI has occurred in China and the United States. Countries with higher levels of development tend to have more influence. Collaboration among authors is fragmented, and collaboration between authors and states needs to be strengthened. Through keyword analysis, the research hotspots are summarized as follows: (1) The effects of traditional and emerging pollutants brought by unconventional water irrigation on soil physicochemical properties, crop growth, and groundwater quality; (2) the health threats caused by pollutants entering the food chain and groundwater; (3) unconventional water utilization technologies, including rainwater harvesting agriculture, precision agriculture, and urban agriculture. Future research hotspots will focus on the mechanisms of pollutant solute transport and transformation in the water–soil–crop system under non-conventional water irrigation conditions and crop physiological responses. We suggest that the research on traditional and emerging pollutants in unconventional water should be strengthened in the future, and the risk control system of unconventional water irrigation should be improved. International cooperation should be strengthened, especially with poor countries in arid regions, to promote the formation of unified international standards and guidelines for non-conventional water irrigation in agriculture.

BA-Optimized Variable Domain Fuzzy PID Control Algorithm for Water and Fertilizer Ratio Control System in Cotton Field

Due to the time-varying, hysteresis and nonlinear characteristics of fertilizer concentration control in the water–fertilizer ratio control system, common control algorithms such as PID and fuzzy PID cannot obtain the expected control effect. In order to accurately control the cotton field water–fertilizer ratio regulation system drip irrigation process of the water–fertilizer ratio that will be controlled within a reasonable range, it is needed to design a bat-optimized variable-domain fuzzy PID water–fertilizer ratio control strategy, through the use of bat algorithm to find out the optimal expansion factor and the best domain of the current conditions, and then according to the changes in working conditions to automatically adjust the fuzzy control of the domain, through the control of the valve openings to change the fertilizer pump back to the amount of water. Realize the fast and precise control of fertilizer concentration in the water–fertilizer ratio control system. Comparative tests were conducted to verify the traditional PID, fuzzy PID, variable domain fuzzy PID and bat-optimized variable-domain fuzzy PID control algorithms. The results show that: if the water–fertilizer ratio is adjusted to 50:1 from the startup, the adjustment time required to reach the target water–fertilizer ratio under the bat-optimized variable-domain fuzzy PID control is 15.29 s, and the maximum overshooting amount is 16.28%, which is a smaller adjustment time and overshooting amount; if the water–fertilizer ratio is adjusted to 40:1 from 50:1, the advantages of bat-optimized variable-domain fuzzy PID are more obvious, with the best balance of response speed, overshooting amount and optimal control effect. In terms of response speed, overshooting amount and regulation time, the optimal balance is achieved, showing the optimal control effect. It is proved that the performance of the water–fertilizer ratio regulation system in cotton field under bat-optimized variable-domain fuzzy PID control designed in this paper can meet the actual production requirements, and these findings can help to develop precise irrigation technology for cotton cultivation under drip irrigation conditions.

Unveiling Drought-Resilient Latin American Popcorn Lines through Agronomic and Physiological Evaluation.

Water stress can lead to physiological and morphological damage, affecting the growth and development of popcorn. The objective of this study was to identify the yield potential of 43 popcorn lines derived from a Latin American germplasm collection, based on agronomic and physiological traits, under full irrigation (WW) and water deficit conditions (WS), aiming to select superior germplasm. The evaluated agronomic traits included the ear length and diameter, number of grains per row (NGR) and rows per ear (NRE), grain yield (GY), popping expansion (EC), volume of expanded popcorn per hectare (VP), grain length (GL), width, and thickness. The physiological traits included the chlorophyll, anthocyanin, and flavonoid content in the leaves. The genetic variability and distinct behavior among the lines for all the agronomic traits under WW and WS conditions were observed. When comparing the water conditions, line L292 had the highest mean for the GY, and line L688 had the highest mean for the EC, highlighting them as the most drought-tolerant lines. A water deficit reduced the leaf greenness but increased the anthocyanin content as an adaptive response. The GY trait showed positive correlations with the VP, NGR, and GL under both water conditions, making the latter useful for indirect selection and thus of great interest for plant breeding targeting the simultaneous improvement of these traits.

Effects of Biochar and Straw Return on Soil Microbial Community Characteristics and Functional Differences in Saline Water Drip Irrigation Cotton Fields

In arid areas, fresh water resources are insufficient, and agricultural water mainly depends on shallow saline groundwater. However, long-term saline irrigation will cause soil salt accumulation and soil environment deterioration, which is not conducive to crop growth. In this study, based on the long-term irrigation of fresh water (0.35 dS·m-1, FW) and saline water (8.04 dS·m-1, SW), biochar (3.7 t·hm-2, BC) and straw (6 t·hm-2, ST) were added to the soil by an equal-carbon design. The aim was to clarify the effects of biochar and straw returning on the physical and chemical properties and microbial community structure of salinized soil. The results showed that saline irrigation significantly increased soil water content, electrical conductivity, available phosphorus, and total carbon content but significantly decreased pH value and available potassium content. The contents of available phosphorus, available potassium, and total carbon in soil were significantly increased by biochar and straw returning, but the conductivity value of soil irrigated with saline water was significantly decreased. The dominant bacteria in each treatment were Proteobacteria, Actinomycetes, Acidobacteria, Chloromycetes, and Blastomonas. Saline water irrigation significantly increased the relative abundance of Blastomonas and Proteobacteria but significantly decreased the relative abundance of Acidobacteria and Actinobacteria. Under the condition of fresh water irrigation, the relative abundance of Chlorocurvula was significantly reduced by the return of biochar. Straw returning significantly increased the relative abundance of Proteobacteria but significantly decreased the relative abundance of Acidobacteria, Actinomyces, Chloromyces, and Blastomonas. Under saline irrigation, the relative abundance of Chlorocurvula and Blastomonas were significantly reduced by biochar return to field. Straw returning significantly increased the relative abundance of Proteobacteria but significantly decreased the relative abundance of Acidobacteria, Actinomyces, Chloromyces, and Blastomonas. LEfSe analysis showed that saline irrigation decreased the potential markers and functional numbers of soil microorganisms.Under saline irrigation, biochar returning increased the number of potential markers and functions of soil microorganisms. Straw returning to field increases the number of potential markers of soil microorganisms. RDA results showed that soil microbial community and functional structure were significantly correlated with EC1:5, SWC, and pH. Saline water irrigation will deteriorate the soil environment, which is not conducive to agricultural production, among which EC1:5, SWC, and pH are important factors driving changes in soil microbial community and functional structure. Using biochar and straw to return to the field can reduce the harm of salt to soil and crops, laying a foundation for improving agricultural productivity.

Phenotypic Dissection of Drought Tolerance in Virginia and Carolinas within a Recombinant Inbred Line Population Involving a Spanish and a Virginia-Type Peanut Lines

Peanut (Arachis hypogaea L.) is a rainfed crop grown in both tropical and subtropical agro-climatic regions of the world where drought causes around 20% yield losses per year. In the United States, annual losses caused by drought are around $50 million. The objective of this research was to (1) identify genetic variation for the normalized difference vegetation index (NDVI), canopy temperature depression (CTD), relative chlorophyll content by SPAD reading (SCMR), CO2 assimilation rate, and wilting among recombinant inbred lines (RILs) derived from two diverse parents N08086olJCT and ICGV 86015, to (2) determine if the physiological traits can be used for expediting selection for drought tolerance, and (3) experimental validation to identify lines with improved yield under water-limited conditions. Initially, 337 lines were phenotyped under rainfed production and a selected subset of 52 RILs were tested under rainout shelters, where drought was imposed for eight weeks during the midseason (July and August). We found that under induced drought, pod yield was negatively correlated with wilting and CTD, i.e., cooler canopy and high yield correlated positively with the NDVI and SPAD. These traits could be used to select genotypes with high yields under drought stress. RILs #73, #56, #60, and #31 performed better in terms of yield under both irrigated and drought conditions compared to check varieties Bailey, a popular high-yielding commercial cultivar, and GP-NC WS 17, a drought-tolerant germplasm.

Using Deficit Irrigation Strategies and Adding Sugarcane Waste Biochar as a Sustainable Material to Sandy Soils for Improving Yield and Water Productivity of Cucumber

This study investigates the potential of biochar to mitigate drought stress in crops. Biochar amendments are increasingly recognized for their ability to enhance soil properties that promote water retention and plant resilience during dry periods. In a study conducted in Egypt, impacts of the application of sugarcane biochar on cucumber production, water productivity, and quality characteristics under deficient irrigation conditions were evaluated. Increasing the biochar application rate under arid region conditions resulted in significant improvements in cucumber yield, water productivity, vitamin C, soluble sugar content, and total soluble solids. The activated sugarcane biochar exhibited desirable properties, including a large surface area (250 m2g−1) and pore size (0.28 cm3g−1), with a microporous nature. The positive effects observed can be attributed to reduced water volume leaving the root zone, enhanced nutrient absorption, increased water holding capacity, and augmented nutrient availability. Based on the results, it is recommended to implement under-irrigation at 75% of full irrigation and apply a biochar rate of 10 tons per hectare to mitigate the environmental impacts of water scarcity and support the development of sustainable agricultural systems. In conclusion, biochar emerges as a valuable soil amendment for bolstering cucumber production and water use efficiency (WUE) under limited irrigation scenarios. Its potential lies in promoting improved soil moisture retention, enhancing nutrient availability for cucumber plants, and potentially mitigating plant stress.

Improved water use efficiency and yield of drip-irrigated pepper under full and deficit irrigation conditions

Improved water use efficiency and yield of drip-irrigated pepper under full and deficit irrigation conditions

Enhancing seed yield and seed quality of wheat (Triticum aestivum L.) through foliar fertigation of micronutrients under restricted irrigation conditions

Enhancing seed yield and seed quality of wheat (Triticum aestivum L.) through foliar fertigation of micronutrients under restricted irrigation conditions

Volatile Characterization of Recovery Minority Grape Varieties from Castilla-La Mancha Region (Spain).

Nowadays, the identification and characterization of grapevine cultivars resilient to climate and water stress while preserving quality traits is crucial for the wine industry. Therefore, the objective of this work was to characterize according to their aromatic potential nine white and six red minority cultivars recently recovered from Castilla-La Mancha region (Spain), subjected to two different water-deficit regimes: rainfed, with subsistence irrigation, and irrigated. For this, the varietal aromatic potential index (IPAv) and the detailed aromatic composition were analyzed via HS-SBSE-GC/MS in extracts of two different pHs. For IPAv values, red varieties did not show a clear trend with respect to irrigation. However, in white minority varieties, higher values were obtained under irrigation conditions. Thus, a clear differentiation of the minority varieties in comparison to the references was observed, primarily attributed to the content of esters and acids, in both white and red varieties. A notable contrast was observed at different pHs, indicating a greater extractability of certain compounds like linalool, under more acidic conditions. This suggests that some recovered minority cultivars could be promising for cultivation in semi-arid regions with limited water, contributing to the sustainability of the wine sector in the future.

Internal Fruit Quality Is Maintained in Eggplant under Mild Long-Term Salt Treatment

Modern Solanum melongena varieties have been developed to improve the content of phenolics, sugars, and nutritionally relevant minerals in fruit. However, fruit composition might be altered due to abiotic stresses like salinity. Physiological and fruit quality traits were evaluated in four eggplant landraces under usual irrigation and moderately salty irrigation conditions (80 mM NaCl). Growing parameters measured included root length, leaf surface, and fresh weight, while fruit composition traits included sugars, phenolics, and mineral content determinations. Few differences were observed for agronomic traits, probably due to the mild tolerance of eggplant to salinity. Some varieties showed signs of salt tolerance like an increase in primary root length to overcome salt stress. Glucose was the metabolite more affected by the salt treatment in the fruit, while phenolic compounds and other metabolites studied were not altered. Significant differences were observed in the main minerals Na, K, Ca, P, and Mg, both between genotypes and treatments. Although salinity produced changes in some physiological and developmental traits, the composition of the fruit was not significantly modified for the accessions tested. Mineral, sugar, and phenolic contents were not particularly altered in unripe fruits, indicating tolerance of eggplant varieties to salinity in terms of fruit quality.

Interactive Effect of Fertilization and Biochar on the Growth of Juniperus scopulorum under Various Shading and Irrigation Conditions

The global demand for landscape trees has been amplified with the increasing anthropogenic activity. South Korea has also witnessed a surge in demand for landscape plants, among others, Juniperus scopulorum gaining popularity for its ecological, economic, adaptability, and management attributes. However, the optimum management practice for high-quality Juniperus seedling production in South Korea remains unknown. This research was conducted on the one-to-two-years-old two cultivars of J. scopulorum, namely Blue Angel and Blue Heaven seedlings, to investigate the combined impacts of varying fertilizer concentrations (0 ppm, 150 ppm, 300 ppm) and biochar content (0% and 20%) under contrasting shading intensities (0%, 35%, 55%) and irrigation levels (200 ml, 400 ml, 800 ml). The study revealed that biochar and fertilizer amendment significantly (p < 0.01 and p < 0.05) enhanced the height and root collar diameter growth in Blue Angel and Blue Heaven in light shade intensity (0–35%) and higher irrigation (400–800 ml) conditions. Similarly, seedlings planted in 20% biochar and 300 ppm fertilizer yielded higher foliar, stem, and root biomass in low shade and higher irrigation conditions. The amount of shade and irrigation and their interactions significantly affected the morphological growth of seedlings for both cultivars, causing positive interaction with soil amendment (biochar and fertilizer application). These findings suggest that efficient seedling production of J. scopulorum management should focus primarily on light shading and moderate irrigation under biochar and higher fertilizer application. The research contributes valuable insights toward optimizing management practices and reducing costs associated with J. scopulorum seedling production in the region. Keywords: biochar, fertilizer, irrigation, Juniperus scopulorum, shading

Comparative characteristics of the durum wheat newest samples based on a complex of agrobiological characteristics

In 2020–2022 at the Dagestan experimental station of the VIR branch 30 samples of durum wheat of different ecological and geographical origins (Russia, Austria, Mexico, Syria, Egypt) were studied under irrigation conditions under winter sowing. The k-66674 Odari, k-67482 Yarina (Krasnodar Territory) and k-32453 Derbentskaya Chernokolosaya (Republic of Dagestan) varieties were sown as standard samples. Over three years of study, a field and laboratory assessment were given for the following characteristics: length of the growing season, resistance to fungal diseases (powdery mildew, brown and yellow rust) and lodging, grain weight per unit area (1 m2), weight of 1000 grains, number of grains in one ear and the mass of grain from one ear. The varieties are recommended as sources of breeding valuable traits (earliness, productivity, large grain size) for further use in breeding and genetic programs for the creation of new adaptive varieties.

Assessing Soil Quality, Wheat Crop Yield, and Water Productivity under Condition of Deficit Irrigation.

Wheat is one of the most important cereal crops in Egypt and all over the world. Its productivity is adversely affected by drought due to deficient irrigation to provide nutrients required for plant growth. In a field experiment, silicon foliar applications at concentrations of 0, 200, and 400 mg L-1 were performed at different irrigation rates ranging from 1000 to 4000 m3 ha-1 to assess water irrigation productivity and wheat crop yield in a calcareous soil under arid climate conditions. Increased irrigation rates led to a significant increase in soil nutrient dynamics, as well as in the number and weight of grains per spike, leaf area index, grain yield, straw yield, and biological yield, with the exception of the weight of 1000 grains. Spraying with sodium silicate had a significant impact on grain yield and harvest index but did not significantly impact the other traits. Furthermore, the interaction between irrigation and silicate application rates showed significance only for grain yield, the number of spikes/m2, and the harvest index. Applying three times irrigation could produce the highest nutrient retention, wheat yield, and water irrigation productivity. No significance was observed between 3000 m3 ha-1 and 4000 m3 ha-1 irrigation, indicating a saving of 25% of applied irrigation water. It can be concluded that applying irrigation at 3000 m3 ha-1 could be a supplemental irrigation strategy. High wheat grain yield can be achieved under deficit irrigation (3000 m3 ha-1) on the northwestern coast of Egypt with an arid climate by spraying crops with sodium silicate at a rate of 400 mg L-1.

Improvement of elements of zonal agro-technology of sweet pepper cultivation on seeds under irrigation conditions of Astrakhan region

Relevance. The purpose of the research was to improve the elements of zonal agricultural technology for cultivating a new variety of sweet pepper Zarnitsa, to study the possibility of increasing productivity, reducing production costs during its seed production through the use of a non-seedling method of cultivation in irrigated conditions and the plant growth regulator Zircon, R.Methodology. Experimental studies were carried out on the experimental field of All-Russian Research Institute of Irrigated Vegetable and Melon Growing (Astrakhan region) in 2022-2023. The establishment of the field experiment and the carrying out of records and observations in the experiment were carried out in accordance with generally accepted methods.Results. It was found that with the seedless method of growing sweet pepper, the period from sowing to the start of fruit harvesting was 12 days shorter. Sweet pepper plants in the seedling method during the fruiting phase had advantages: in plant height by 9.3%, in the number of lateral shoots by 21.2%, in leaf weight by 7.0%, in average fruit weight by 6.1%. The highest yield, on average 31.6 t/ha, was obtained using the seedling method; when sowing seeds in the ground, it was 3.8% lower. Replacing the seedling method of cultivation with a non-seedling method contributed to a reduction in production costs by 74.7 thousand rub./ha, production costs by 1.9 thousand rub./t, production profitability by 1.2 times, due to savings in labor resources and working capital for growing and planting seedlings. Replacing the seedling method of cultivation with a non-seedling method helped reduce production costs by 74.7 thousand rub./ha, production costs by 1.9 thousand rubles/t, the profitability of production of sweet pepper products and seeds by 1.2 times, due to savings labor resources, working capital for growing, planting seedlings. A single treatment with the plant growth regulator Zircon, P (30 ml/ha) at the beginning of flowering contributed to a significant increase in plant biometric parameters: height by 12.2%, number of lateral shoots by 30.8%, leaf weight by 14.3%, yield by 2.4 t/ha (7.9%), compared to the control (30.4 t/ha), an increase in sugar content by 0.2%, vitamin C by 4 mg% and seed yield by 9 kg/ha (8.7%). The sowing qualities of sweet pepper seeds in all variants of the experiment met the standard requirements and were – 94-95% in terms of germination and – 92-94% in terms of germination energy. The highest level of profitability of 204.9% was obtained as a result of using a growth regulator; in the option without treatment it was lower by 14.4%.

Colonization of Solanaceous crops by endophytic and rhizospheric plant growth-promoting bacteria from the native Solanaceae Solanum hindsianum Benth

Plant-associated bacteria are an important tool for sustainable agriculture since the have been shown to play a significant role in the health and productivity of plants through various mechanisms. However, commercial inoculants often fail to produce desired effects due to colonization issues and lack of adaptation to local conditions. In this study, we aimed to evaluate the potential of plant growth-promoting bacteria (PGPB) isolated from Solanum hindsianum, a native plant from the Sonoran Desert, to colonize and promote growth in Solanaceae crops under different irrigation conditions. First, endophytic bacteria were screened for various plant growth-promoting traits, and selected strains were identified as Bacillus, Brevibacillus, Pseudomonas, Acinetobacter, and Siccibacter. Then, endophytic and rhizospheric Pseudomonas isolates, were tested for their tolerance to salinity and osmotic stress and for their ability to induce auxin-responsive gene expression and promote plant development in Arabidopsis. All strains induced strong expression of an auxin reporter gene, while significantly improving root and plant morphology, and showed tolerance to osmotic and salinity stress. In colonization experiments, these strains successfully colonized the root crown and rhizosphere of chili, tomatillo, and tomato plants. However, the endophytic strain showed better colonization ability, especially under low irrigation conditions. Overall, this study demonstrates the potential of native PGPR strains to colonize and promote growth in Solanaceae crops under specific environmental conditions.

Nursery cultural practices influence morphological and physiological aspen seedling traits: implications for post-fire restoration

Aspen forests are threatened by the impacts of a changing climate and are showing large-scale mortality with meager natural regeneration to restore these loses. Therefore, there is an increasing demand for high-quality aspen seedlings to assist with forest restoration efforts. Nursery cultural practices can be used to alter aspen seedling traits to improve adaptability to dry planting conditions. In this study, the effects of container size (SC10 and D30; 158 and 490 mL, respectively) and nursery irrigation treatment (high and low irrigation; 90% and 70% container capacity, respectively) on seedling growth and a suite of morphological and physiological traits were investigated. The combination of large container size and low irrigation treatment resulted in seedlings with lowest height-to-diameter ratio and specific leaf area, which are desired traits for seedling performance on dry sites. Additionally, seedlings exposed to low irrigation conditions at the nursery stage had a lower (more negative) osmotic potential at full turgor, suggesting a higher likelihood of drought tolerance. Overall results from this study provide insight into utilizing nursery cultural practices to produce seedlings with target characteristics that may ultimately lead to establishment on harsh, dry planting sites in large-scale reforestation projects.

Deficit Irrigation-Based Improvement in Growth and Yield of Quinoa in the Northwestern Arid Region in China

Given the current global water scarcity issues, which particularly affect arid regions such as northwestern China, it is crucial to find crop planting patterns that result in efficient water resource utilization. Quinoa, as a drought-resistant and highly nutritious crop, has garnered significant attention from agricultural researchers in recent years. From 2019 to 2020, a series of experimental studies were conducted under non-mulching drip irrigation conditions to investigate the growth adaptability and the response to different irrigation levels of quinoa in an arid region in northwestern China. A comparative analysis of quinoa’s dry matter accumulation, yield, thousand-grain weight, harvest index, and water use efficiency under varying irrigation levels revealed that increasing irrigation significantly enhanced quinoa’s dry matter accumulation and yield. By optimizing the irrigation strategies, we found that the water-saving practice of initiating moderate irrigation in the sensitive water-demanding stages (flowering and fruiting) of quinoa increased the yield. The experiment results showed that, in 2020, the optimal irrigation amount was 3675 m3·ha−1 during a 14-day irrigation cycle, meeting quinoa’s growth requirements while improving water resource utilization efficiency. This study not only provides a scientific basis for the efficient cultivation of quinoa in the arid regions of northwestern China, but also offers new insights into and technical support for agricultural water resource management in the region, contributing to the sustainable development of agriculture in arid areas.