Effect Of Deficit Irrigation Research Articles

Effect of water deficit irrigation and bio-fertilizers on growth, yield and quality of sugar beet

Effect of water deficit irrigation and bio-fertilizers on growth, yield and quality of sugar beet

New approaches to the effects of Si on sugarcane ratoon under irrigation in Quartzipsamments, Eutrophic Red Oxisol, and Dystrophic Red Oxisol

BackgroundC:N:P homeostasis in plants guarantees optimal levels of these nutrients in plant metabolism. H However, one of the causes to the effects of deficit irrigation is the loss of C:N:P homeostasis in leaves and stems that causes reduction in the growth of sugarcane. Being able to measure the impact of water deficit on C:N:P homeostasis in plants from the stoichiometric ratios of the concentrations of these nutrients in leaves and stems. This loss causes a decrease in nutritional efficiency, but can be mitigated with the use of silicon. Silicon favors the homeostasis of these nutrients and crop productivity. The magnitude of this benefit depends on the absorption of Si by the plant and Si availability in the soil, which varies with the type of soil used. Thus, this study aims to evaluate whether the application of Si via fertigation is efficient in increasing the absorption of Si and whether it is capable of modifying the homeostatic balance of C:N:P of the plant, causing an increase in nutritional efficiency and consequently in the production of biomass in leaves and stems of sugarcane ratoon cultivated with deficient and adequate irrigations in different tropical soils.ResultsWater deficit caused biological losses in concentrations and accumulation of C, N, and P, and reduced the nutrient use efficiency and biomass production of sugarcane plants cultivated in three tropical soils due to disturbances in the stoichiometric homeostasis of C:N:P. The application of Si increased the concentration and accumulation of Si, C, N, and P and their use efficiency and reduced the biological damage caused by water deficit due to the modification of homeostatic balance of C:N:P by ensuring sustainability of the production of sugarcane biomass in tropical soils. However, the intensity of attenuation of such deleterious effects stood out in plants cultivated in Eutrophic Red Oxisols. Si contributed biologically by improving the performance of sugarcane ratoon with an adequate irrigation due to the optimization of stoichiometric ratios of C:N:P; increased the accumulation and the use efficiency of C, N, and P, and promoted production gains in biomass of sugarcane in three tropical soils.ConclusionOur study shows that fertigation with Si can mitigate the deleterious effects of deficient irrigation or potentiate the beneficial effects using an adequate irrigation system due to the induction of a new stoichiometric homeostasis of C:N:P, which in turn improves the nutritional efficiency of sugarcane cultivated in tropical soils.

Effects of postharvest deficit irrigation on sweet cherry (Prunus avium) in five Okanagan Valley, Canada, orchards: II. Phenology, cold hardiness, fruit yield, and quality

Irrigated agriculture in semi-arid regions is expected to increase in the future, which puts greater demands on scarce water resources. Sustainable irrigation strategies in semi-arid regions will support agricultural resilience to climatic change. The response of “Sweetheart”/Mazzard sweet cherry trees ( Prunus avium L.) to postharvest deficit irrigation (PDI), as a water conservation method, was studied over three seasons (2019–2022) in the semi-arid Okanagan Valley of British Columbia, at five commercial orchards. The following irrigation treatments were applied; ( i) a control of full irrigation, irrigated according to conventional growers’ practice at each orchard, ( ii) PDI-30: 27%–33% reduction in irrigation volume, after harvest (67%–73% of control), and ( iii) PDI-50: 47%–52% reduction in irrigation volume, after harvest (48–53% of control). Spring phenology (the timing of flower bud development, from side green to full bloom), flower bud moisture content and cold hardiness, and fruit yield and quality (before and after cold storage and shelf-life conditions) were assessed to determine if PDI altered fruit development over the subsequent growing season. Neither PDI-30 nor PDI-50 caused changes in the timing of flower bud phenology, cold hardiness or moisture content relative to the control. PDI treatments also had no effect on fruit yield or fruit quality at harvest or after storage and shelf-life conditions. These results suggest PDI could be used to reduce irrigation water use in semi-arid regions, like the Okanagan Valley, without affecting sweet cherry production or fruit quality.

Basic economics on deficit irrigation and water quality dynamics for horticulture production in a greenhouse environment

The objective of this paper is to examine the impact of varying deficit irrigation level and water quality scenarios on economic responses of tomatoes (Solanum lycopersicum cv. Izmir) produced in a greenhouse environment. Groundwater, recycled wastewater and a blend of both were selected as water qualities. Four irrigation scenarios were maintained including soil moisture at 60%, 70%, 80% and 100% of field capacity. The treatment maintaining soil moisture at 100% field capacity was control in this study for each water quality. The selected irrigation method and the soil texture were the drip and loamy sand respectively. The effects of deficit irrigation and water quality on the benefit-cost ratio, revenue generated per m3 of water usage, cost function and net financial return were examined. Benefit-cost ratio was a maximum of 1.37 for the control treatment of recycled wastewater. All the selected deficit irrigation treatments produced the benefit-cost ratio more than one except 60% field capacity level. Revenue generation per m3 of water usage was found the highest in treatments maintaining soil moisture content at 80% field capacity despite of water quality. Based on the benefit-cost ratio, cost function and revenue generated per cubic meter of water use, this study recommended the deficit irrigation level at 80% field capacity as the most cost-effective and water efficient strategy for greenhouse grown tomatoes.

Effect of Deficit Irrigation On Yield, Water Productivity, Energy Indices and Economic Productivity in Eggplant Cultivation

Effect of Deficit Irrigation On Yield, Water Productivity, Energy Indices and Economic Productivity in Eggplant Cultivation

Effects of biochar addition and deficit irrigation with brackish water on yield-scaled N2O emissions under drip irrigation with mulching

Biochar has been proven to have great potential for mitigating greenhouse gas emissions and improving crop growth. However, the effects of biochar addition on yield-scaled N2O emissions in a mulched and drip-irrigated maize field using different irrigation water qualities and quantities remain unclear. A two-year field experiment was conducted to examine the effects of biochar addition, irrigation level and water salinity on soil N2O emissions, maize yield and grain N uptake in Northwest China. Eight treatments in total included the combination of two biochar addition rates of 0 t/ha (B0) and 60 t/ha (B1), two irrigation levels of full (W1) and deficit irrigation (W2, W2 = 1/2 W1) and two water salinity levels of freshwater (S0, 0.71 g/L) and brackish water (S1, 4 g/L). The soil properties, N2O emission fluxes, maize yield and grain N uptake, along with the abundances of N-cycle functional marker genes were measured during the two growing seasons. Soil water-filled pore space (WFPS), soil NH4+-N and NO3--N contents accounted for the majority of the variation in the dynamic changes of N2O fluxes. Deficit irrigation had lower N2O emissions compared with full irrigation, which was more pronounced in the second year. Relative to freshwater irrigation, brackish water irrigation increased N2O emissions under W1, but freshwater and brackish water irrigation had similar N2O emissions under W2 in both years. Biochar addition effectively mitigated N2O emissions by 29.4–31.0% and 17.9–29.2% under different irrigation treatments in 2020 and 2021, respectively. The continuous drought induced by deficit irrigation weakened the effectiveness of biochar in reducing N2O emissions. The differences in N-cycle functional marker genes could not reflect the variation in cumulative N2O emissions among treatments. Under all irrigation treatments excluding W2S1, biochar addition improved the total maize yield and grain N uptake over the two-year period by 4.06–10.74% and 5.57–8.63%, respectively. Brackish water and deficit irrigation increased grain and grain N yield-scaled N2O emissions, whereas biochar addition reduced both of them. Overall, these findings suggest that biochar addition can effectively reduce N2O emissions and increase yield and grain N uptake under brackish water and deficit drip irrigation with mulching in a maize field system, and thus adding biochar can help with achieving the sustainability of agricultural production in areas with limited freshwater resources.

Managing Drought Risk on Lentil Using Deficit Irrigation in Arid Zones

Grain legumes (pulses) are important crops for global food security, especially in developing countries. They also play an important role in enhancing sustainability through intensification and diversification of agricultural production systems. Meanwhile, the deficit irrigation strategy is one of the most important options for reducing water losses and maximizing water use efficiency in arid zones. A 2-year field experiment was conducted in the Agricultural Research Station, Higher Education Complex of Saravan during the growing seasons of 2018 and 2019. The experiment was split plot based on a randomized complete block design (RCBD) with four replications. The main plots included four levels of irrigation (60, 80, 100, and 120%). Subplots were two different landraces from Iran for lentil crop (Baluchestan and Kurdestan). The results revealed that the effect of deficit irrigation was significant on grain yield, biological yield, harvest index, and water use efficiency. Apart from the landraces, with increasing water consumption, the grain yield of control treatment (100%) grew by 107% in comparison to 60% irrigation treatment, but this elevation was not significant at 120% level in comparison to the control treatment. Further, 120% irrigation treatment led to reduction in water use efficiency. The highest water use efficiency (2.9 kg ha-1 mm-1 ) was obtained in 80% irrigation treatment with 10% reduction in grain yield compared with control treatment. The highest harvest index was observed in the interaction of Baluchestan zones × 80% water treatment (0.24). Although the interaction of Baluchestan landrace × 80% water treatment had 10% grain yield lower than control treatment, its biological yield decreased by 27% compared to control treatment, which eventually led to 20% rise of the harvest index. Thus, our study revealed that deficit irrigation was a useful method to protect the water resources and could be used in cultivation of other plants in arid zones.

The effects of arbuscular mycorrhizal fungi and deficit irrigation on the yield and sugar content of watermelons (Citrullus lanatus)

Many studies have demonstrated that arbuscular mycorrhizal fungi (AMF) and deficit irrigation (DI) have positive effects on the fruit yield or quality. This study aims to test whether the watermelon sugar content and yield can be improved by appropriate amounts of AMF and DI methods and to clarify the underlying physiological mechanism. Diploid and triploid watermelon cultivars and their pumpkin rootstock-grafted seedlings were treated with AMF, DI and DI + AMF in a randomised complete block design with five replications. The results showed that DI significantly reduced the relative water content (RWC), PN, alkaline α-galactosidase activity, but increased the insoluble acid invertase (IAI), sucrose synthase (SuSy) and sucrose phosphate synthase (SPS) activities compared with the well-watered (WW) treatment, which led to a decrease in the fruit yield and an increase in the fruit sugar content. Although the AMF improved the RWC, PN and alkaline α-galactosidase, IAI, SuSy and SPS activities in all the watermelon lines under both the DI and WW conditions, the improvement magnitude of these parameters was more pronounced in the pumpkin-root watermelon lines than the corresponding own-root watermelon lines, especially under the DI condition. The integrated application of AMF and DI increased the fruit yield to a level similar to the WW value in the pumpkin-root watermelon lines and sugar content to an optimal level in all the watermelon lines.

Effects of Deficit Irrigation and Fertigation on Growth, Yield and Water Productivity of Greenhouse-Grown Cucumber

Low water productivity has caused the wastage of water in agricultural production. Water productivity can be increased by using drip irrigation for vegetables on raised beds in greenhouses. For this purpose, a greenhouse study was conducted on sandy loam soil at the Experimental Research Station of the Asian Institute of Technology, Thailand. The experiment was designed in randomized complete block design having ten treatments using three irrigation levels [100%, 80%, 60% of actual evapotranspiration (ETc)] and three recommended dose of fertilizer (RDF) levels [100%, 80%, 60%]. Furrow irrigation with 100% of RDF was used as a control treatment. Data of crop and water productivity were recorded; the results showed that treatment T5 (W80%ETc F80%RDF) under deficit irrigation and fertigation recorded the highest mean fresh fruit yield of 66.71 t/ha while the full irrigation treatments T1 (W100% ETc F100% RDF) and T2 (W100%ETc F80%RDF) recorded the lowest mean fresh fruit yield of 12.9 t/ha and 13.9 t/ha, respectively, as against 9.6 t/ha for the control plot. Also, T5 recorded the highest water productivity of 14.47 kg/m3 while full irrigation treatments (T1 and T2) recorded the lowest water productivity of 2.52 kg/m3 and 2.73kg/m3, respectively, as against 1.37 kg/m3 for the control plot. A deficit irrigation level of 80% of ETc with a fertilizer level of 80% of RDF was found most suitable for sandy loam soil to improve crop growth, yield and water productivity for greenhouse-grown cucumber under the drip irrigation system. The results also suggest that a 20% deficit irrigation and fertilizer approach may be a good strategy for increasing water productivity when full irrigation is not possible due to limited water supplies.

On-Farm Adaptation to Climate Change: Assessment of Effects of Groundwater-Based Deficit and Supplementary Irrigation on Soil Quality Under Semi-Arid Ecosystems

Agriculture is one of the sectors most affected by climate change, especially through the reduction in the number of rainy days in semi-arid areas, which require deficit supplementary irrigation (DSI) to minimise crop failures. Few studies have utilised soil quality indices (SQIs) to evaluate the quality changes of soils under DSI practices in semi-arid agricultural ecosystems. This paper examines the effects of DSI activities on soil quality in the Ingawa area of Nigeria’s semi-arid region. Plots subjected to different years of DSI (3, 5, 6, 8, 10, 11, 14 and 15 years) practices were chosen to serve as the controls. Soil samples were collected from each of the nine sites at depths ranging from 0 cm to 20 cm and 25 cm to 40 cm. The collected samples were analysed for physico-chemical properties. Soil quality change was estimated by computing percentage equivalence values that define the extent to which mean values of soils under DSI vary from those of the control. The results obtained show that the practices have caused significant negative changes in the levels of most of the properties considered, with significant deleterious effects on the selected physical and chemical indicators of soil quality to extents that might preclude sustainable agriculture on the soils. Potassium, organic carbon, organic matter, and some other essential nutrients needed for plant growth and soil stability have dropped a lot in irrigated farms compared to control farms, but salinization hasn't happened much. It was suggested that the right steps be taken to prevent the loss of important nutrients that crops need to grow well.

Effect of deficit irrigation and soil fertility management on wheat production and water productivity in the Upper Blue Nile Basin, Ethiopia

In the Ethiopian Upper Blue Nile Basin, like in other regions in the world, agricultural productivity is declining due to water scarcity owing to longer dry seasons coupled with soil acidity−induced fertility problems. Wheat is one of the major food security crops in Ethiopia but its productivity is reduced due to water scarcity, especially during the irrigation season. Addressing these problems might be essential to increase productivity. This study explores the effect of deficit irrigation (DI) combined with lime, manure and inorganic fertilizer on wheat production and water productivity (WP) in the Koga irrigation scheme, Ethiopia. Four levels of DI strategies (100% ETc or 0% deficit as a control, 80%, 60% and 50% ETc) were applied for two irrigated seasons. Five levels of soil fertility management were applied for four consecutive cropping seasons: (i) 0.86 t ha−1 lime combined with 3 t ha−1 manure and full dose urea and NPS−B (hereafter referred to as inorganic fertilizer) (L3); (ii) 1.15 t ha−1 lime combined with 3 t ha−1 manure and full-dose inorganic fertilizer (L2); (iii) 1.43 t ha−1 lime combined with 3 t ha−1 manure and full dose inorganic fertilizer (L1); (iv) 3 t ha−1 manure combined with full dose inorganic fertilizer (M); and (v) full dose inorganic fertilizer alone (C). The grain yield and biomass data were collected at harvest from a sample area of 2 m × 3 m from each plot with three replicates. The effect of DI and liming, as well as manuring on average grain yield and biomass, were highly significant. Under all irrigation scenarios, higher grain yield and biomass were found at L1, L2, L3 and M (in that order), compared with C. The highest WP was obtained at 50% ETc irrigation dose, compared with 60%, 80% and 100% ETc (in that order). Yet, the lowest WP was found at C under all irrigation scenarios compared with L1, L2, L3 and M. The WP increased when the amount of water supply decreased and liming doses increased. The application of full dose lime and manure combined with 50% ETc DI resulted in comparable grain yield, biomass and WP as 100% ETc full irrigation at L3 and M. It could be concluded that liming and manuring could be used to mitigate the yield penalty effect of DI in the study area. In scenarios where farmers have to pay for water, profitability rises as the irrigation water supply reduces. Thus, under such conditions, a 50% ETc irrigation scenario is more profitable than scenarios with 60%, 80% and 100% ETc irrigation.

Effect of deficit irrigation on some growth parameters, yield and water productivity of broad bean crop

Effect of deficit irrigation on some growth parameters, yield and water productivity of broad bean crop

Deficit irrigation and reflective mulch effects on peach quality and storage performance

Deficit irrigation and reflective mulch effects on peach quality and storage performance

Irrigation and Crop Load Management Lessen Rain-Induced Cherry Cracking.

The combined effects of deficit irrigation and crop load level on sweet cherry (Prunus avium L.) physiological and agronomic response were evaluated during the 2019 season in a commercial orchard located in southeastern Spain. Two irrigation treatments were imposed: (i) control treatment (CTL) irrigated above crop water requirements at 110% of crop evapotranspiration (ETC) and (ii) a deficit irrigation treatment (DI) irrigated at 70% ETC. Within each irrigation treatment, crop load was adjusted to three levels: 100% (natural crop load-high), 66% (medium crop load), and 33% (low crop load). The water relations results were more affected by the irrigation strategies applied than by the crop load management. The deficit irrigation strategy applied reduced soil water availability for DI trees, which led to a continuous decrease in their gas exchange and stem water potential. At harvest, the fruit water potential and osmotic potential of cherries from the DI treatment resulted in significantly lower values than those measured in cherries from CTL trees. On the other hand, both the irrigation strategies imposed and the crop load management used impacted fruit quality. Trees with the lowest level of crop load had fruits of greater size, regardless of the irrigation treatment assayed, and in the DI treatment, cherries from the trees with the lowest crop load were darker and more acidic than those from the trees with the highest crop load. Our results emphasize the different effects that rainfall before harvest has on mature cherries. Thus, cracked cherries at harvest represented 27.1% of the total yield of CTL trees while they were 8.3% of the total yield in DI trees. Cherries from CTL trees also showed a greater cracking index than those from DI trees. Moreover, a linear relationship between crop load and fruit cracked at harvest was observed, particularly for the CTL treatment; thus, the lower the crop load, the greater the proportion of cracked cherries.

Effects of postharvest deficit irrigation on sweet cherry (Prunus avium) in five Okanagan Valley, Canada, orchards: I. Tree water status, photosynthesis, and growth

The timing and availability of water supply are changing in the Okanagan Valley, and the availability of irrigation water in the late summers is a growing concern. Postharvest deficit irrigation (PDI) is a strategy that can be used to reduce water demands in sweet cherry orchards; previous studies in this region have reported no change in plant physiology or tree growth with irrigation volume reductions of up to 25%, postharvest. However, the effects of more severe postharvest reductions in irrigation volume remain unknown. We compared the effects of full irrigation (100% of conventional grower practice through the growing season) with 27%–33% reductions in irrigation postharvest (∼70% of conventional grower practice) and 47%–52% reductions in irrigation postharvest (∼50% of conventional grower practice) over a 3-year period (2019–2021) in five commercial sweet cherry orchards that ranged in elevation and latitude across the Okanagan Valley, BC, Canada. In the growing season following treatment application, PDI had no effect on stem water potential or photosynthesis in any year and at any site; there were also no effects of PDI treatment on tree growth. Findings from this study suggest that postharvest stem water potentials from −0.5 to −1.3 MPa, and one-time stem water potentials as low as −2.0 MPa, have no lasting effects on future plant water status, rates of photosynthesis, or plant growth. PDI shows potential as an effective water-saving measure in sweet cherry orchards in the Okanagan Valley.

The Alleviation Effects of Biostimulants Application on Lettuce Plants Grown under Deficit Irrigation

Τhe aim of this study was to examine the potential of using biostimulants for the amelioration of deficit irrigation effects on field-grown lettuce plants growth parameters (cv. Doris (Romaine type) and cv. Manchester (Batavia type)). Therefore, five biostimulatory products that differed in their composition were evaluated, including seaweed extracts, amino acids, humic and fulvic acids, macronutrients, Si, and vegetable proteins, while a control treatment with no biostimulants applied on plants was also considered. Plants were subjected to three irrigation regimes, e.g., rain-fed plants (RF), deficit irrigation (I1; 50% of field capacity) and normal irrigation (I2; 100 of field capacity). The results indicate that the application of seaweed extracts, macronutrients, and amino acids (SW treatment) alleviated the negative effects of deficit irrigation on plant growth and chlorophyll content of Romaine-type plants. On the other hand, Batavia-type plants were more susceptible to water stress, since the highest crop yield plant was observed under the full irrigation treatment and the application of vegetal proteins and amino acids (VP treatment). In general, the application of biostimulants on the Romaine type improved plant growth under water shortage conditions compared with fully irrigated plants in almost all measurements, whereas the Batavia-type plants appeared to be more sensitive to deficit irrigation. Therefore, the ecofriendly practices of deficit irrigation and biostimulant application could be useful in leafy vegetable production on a genotype-depended manner.

Effect of deficit irrigation on water status, metabolic characters, fruiting, yield, and quality of clementine trees under Tunisian semi-arid conditions

Effect of deficit irrigation on water status, metabolic characters, fruiting, yield, and quality of clementine trees under Tunisian semi-arid conditions

Interactive effects of deficit irrigation and vermicompost on yield, quality, and irrigation water use efficiency of greenhouse cucumber

Interactive effects of deficit irrigation and vermicompost on yield, quality, and irrigation water use efficiency of greenhouse cucumber

Fruit growth, carbon allocation, and related enzymes in tomato under different irrigation and potassium application regimes

AbstractBackgroundThe increasing concentration of atmospheric CO2 not only affects the growing environment of crops but also aggravates the global greenhouse effect and further aggravates the problem of water shortage. The combined effect of water deficit and potassium (K) application has not been widely studied.AimsA pot experiment was conducted to investigate the effect of deficit irrigation (DI) and K application at different growth stages on carbon allocation and enzyme activities related to sugar metabolism.MethodsTomatoes were transplanted and planted on April 26, 2017 and harvested on August 15, 2017. Four irrigation regimes were implemented with two water levels (full irrigation‐W and DI‐W/2) in different growth stages, and each water treatment was equally divided into two subgroups: with K (K1) and without K (K0). Fruits from the first to fourth trusses of the tomato plants were sampled. Tomato growth, carbon allocation, and related enzyme activities were measured.ResultsThe fresh weight (FW), dry weight, and relative growth rate of dry mass were sensitive to irrigation amount under K fertilization, enhancing the promotion effect of irrigation on fruit. Meanwhile, carbon allocation was sensitive to irrigation amount under K regime. Sucrose synthase (SuSy), acid invertase (AI), and sucrose phosphate synthase (SPS) were also highly sensitive to irrigation amount under K application condition. Starch phosphorylase displayed a quadratic parabola for irrigation amount, and adenosine diphosphate glucose pyrophosphorylase (AGPase) was highly sensitive to irrigation amount without K fertilization. Carbon in the form of other carbohydrates, carbon in the form of soluble sugar (Csol), and fruit water content were the factors that had the greatest influence on the principal components. Classification by K‐means algorithm and canonical correlation analysis showed that FW, fructose, sucrose, and starch could be used as significant indicators of the dry matter components of the fruit for the treatment without K. In the case of K regime, SuSy, AGPase, AI, and Csol could be used as a significant indicator of the correlation analysis of carbon metabolism activity.ConclusionsThe factors related to the improvement of fruit quality and carbon allocation by deficient irrigation and K application were explored. Water stress changed the distribution of photosynthetic carbon between starch and soluble sugar. K application further changed the balance between soluble sugars and other compounds. In particular, it significantly increased the carbon content of soluble sugars and decreased that of other compounds. AI and SuSy are key enzymes affecting carbon metabolism under water‐deficient conditions.

Deficit mulched drip irrigation improved yield and quality while reduced water consumption of isatis indigotica in a cold and arid environment.

Deficit irrigation is an effective alternative to traditional irrigation, as it improves crop productivity and conserves water. However, crops may be sensitive to deficit irrigation-induced water stress at different periods. To access the effect of deficit irrigation on the growth, water consumption characteristics, yield, and quality of Isatis indigotica (woad), we performed a three-year (2017-2019) mulched drip irrigation field experiment. Woad plants were provided adequate water supply at the seedling stage but were subjected to mild (65–75% field water capacity FC), moderate (55–65% FC), and severe (45–55% FC) water deficit at the vegetative growth, fleshy root growth and fleshy root maturity stages, respectively; plants supplied with adequate water throughout the growth period served as a control (CK, 75–85% FC). The water consumption characteristics, agronomic traits, dry matter content and distribution, yield, and quality of these plants were measured at various growth stages. The results showed that the total water consumption in water deficit was significantly less than that in CK by 4.44–10.21% (P< 0.05). The dry matter content of plants treated with moderate (WT2 and WT5) and severe (WT3) water deficit was reduced by 12.83–28.75%. The economic yield of mild water deficit-treated plants was higher during vegetative growth (WT1) and fleshy root growth (WT4), while the water use efficiency of these plants was significantly increased by 7.84% and 6.92% at the two growth stages, respectively. Continuous mild water deficit (WT4) enhanced the contents of indigo, indirubin, (R,S)-goitrin, polysaccharides, and soluble proteins during vegetative growth and fleshy root growth, while moderate and severe water deficit were detrimental to the quality of woad plants. Thus, continuous mild water deficit during vegetative and fleshy root growth periods (WT4) is optimal for the cultivation of woad in the cold and cool irrigation district of the Hexi Oasis region.