Normal Irrigation Research Articles

Application of Zinc Fertilizer and Mycorrhizal Inoculation on Physio-Biochemical Parameters of Wheat Grown under Water-Stressed Environment

Drought stress and poor zinc (Zn) are major constraints for commercial agriculture. Their detrimental effects significantly decrease crop’s growth and yield. Less water uptake disturbs the metabolic processes in plants. However, the deficiency of Zn leads to the inactivation of many enzymes. It is well documented that cereal crops, especially wheat, are susceptible to drought and Zn deficiency. Scientists suggest the supplementation of Zn along bio-fertilizers for the sustainable management of these issues. That is why the current experiment was conducted to explore the best combination of Zn and bio-fertilizer for wheat. There were two different recommended concentrations of Zn sulfate (Zinc level 1 (Zn1) = 20 and Zinc level 2 (Zn2) = 40 kg ha−1) applied under normal irrigation (75% field capacity = FC) and severe drought stress (40% FC). Sole and combined inoculation of arbuscular mycorrhizal fungi (AM) with Zn1 and Zn2 was also performed. Osmotic stress (40% FC) significantly decreased the examined growth parameters. It also significantly enhanced antioxidant and oxidative indicators in wheat. A significant increase in root fresh weight, root dry weight, and shoot length while a significant decrease in EL, SOD, POD over the control validated the efficacious role of Zn2 + AM. It is concluded that Zn2 + AM can improve wheat root fresh weight and root length wheat under 40% FC. Under different climatic zones, wheat varieties, and soil types, more investigations are recommended to declare Zn2 + AM as the best amendment for improving wheat growth attributes under osmotic stress.

The effect of exogenously applied plant growth regulators and zinc on some physiological characteristics and essential oil constituents of Moldavian balm (Dracocephalum moldavica L.) under water stress.

The online version contains supplementary material available at 10.1007/s12298-021-01084-1.

Shifts in biochemical and physiological responses by the inoculation of arbuscular mycorrhizal fungi in Triticum aestivum growing under drought conditions.

A decrease in rainfall is one of the main constraints on wheat production, although the association of wheat with arbuscular mycorrhizal fungi (AMF) may be an alternative for crop production under drought conditions. In the present study, we used three wheat cultivars (Purple, Ilustre and Maxi Baer) inoculated with two AMF strains, one obtained from the hyperarid Atacama Desert (northern Chile; Fm) and the other obtained from southern Chile (Cc). Plants were maintained under two irrigation conditions (normal irrigation and drought) and the physiological behaviour and enzymatic and nonenzymatic antioxidant activities in the shoots were determined. In addition, the phenolic compounds were identified by high-performance liquid chromatography-dioide array detection-electrospray ionization-tandem mass spectrometry and quantified. AMF colonization produced higher levels of efficiency of photosystem II and photosynthetic pigments. High values of catalase in Purple-Cc, ascorbate peroxidase in Purple-Cc, glutathione reductase in Maxi-Cc and superoxide dismutase in Purple-Cc, all under stress, were registered. Of the inoculated cultivars, Purple-Cc showed the highest flavonoid levels, whereas hydroxycinnamic acids were higher in Maxi-Fm without drought, with apigenin and luteolin being the most abundant. High levels of phenols were present in the Ilustre-Fm plants without drought. Under normal irrigation, high levels of antioxidant activity were registered in the AMF treatments, whereas, under stress conditions, in general, high values were observed under the Fm inoculation. Our results showed that the greatest antioxidant activity and phenolic content occurred in wheat plants inoculated with AMF, indicating their influence on coping with water stress, which is of importance in vast areas where global climate change is resulting in diminished rainfall. © 2021 Society of Chemical Industry.

Evaluation crop indices of canola spring genotypes in terminal drought stress conditions and foliar application of Potassium silicate

Introduction Drought is a restriction in crop production in arid and semiarid regions. It is forecast that climate change may cause droughts shortly. After oxygen, silicon (Si) is the second most common element in the soil. In reducing both biotic stress (e.g., plant diseases and pest damage) and abiotic stresses such as salinity, drought, aluminum toxicity, heavy metal toxicity, nutrient imbalance, lodging, radiation, high temperature, wounding, and freezing. Materials and Methods In order to study the effects of terminal drought stress and foliar application of potassium silicate on yield and canola spring genotypes components, a factorial split-plot test was conducted in Karaj, Iran in a full randomized block configuration with three replications for two years of cultivation (2016-2018). The irrigation was performed at two levels in this study, including routine irrigation (control) and interruption of irrigation from the pod formation stage. Potassium silicate foliar application at two levels comprised of 0 and 4 g liter-1 in factorial status in main plots and five Brassica napus L. genotypes including OG × AL, RGS × SLM, DALGAN, RGS003 and RGS × Okapi in subplots. SAS Ver 9.1 statistical analysis was used for variance analysis. Results Combined variance analysis showed that the impact of the year on some characteristics seed number in silique, silique length and seed yield was significant. Also, the effect of irrigation was significant on seed yield. The effect of genotype on plant height was significant indicating that the genotypes had different reactions. The interaction effect of irrigation × genotype on Harvest index was significant. The interaction effect of Irrigation × Potassium Silicate × Genotype on branch number, silique number, silique length, seed number in silique, seed weight, biological yield, seed yield, oil content and oil yield was significant. The mean comparison of irrigation and Potassium silicate interaction demonstrated that the most grain yield was observed in normal irrigation and the least value related to cut off irrigation at pod formation stage. The results indicated that, irrigation, foliar application of Potassium silicate and their interaction had significant effect on growth and agronomic traits and increased them. Conclusions Finally, our study showed the beneficial effects of Potassium Silicate in improving the drought tolerance of canola plants, especially at the end of the season. This can provide a basis for attempting new strategies to reduce the damage from drought and create a functional link between the role of silicon, physiological response and tolerance to drought stress in canola plants. According to the results, in the case of application of Potassium Silicate and normal irrigation, the promising genotype of OG×AL, with the highest seed and oil yield, is recommended as standard. Also, in the case of application of Potassium Silicate and late-season drought stress (restricted irrigation from the pod formation stages), RGS × SLM and DALGAN with the highest seed yield, is recommended.

Potassium fertilization improves growth, yield and seed quality of sunflower (Helianthus annuus L.) under drought stress at different growth stages.

Water scarcity is a major concern for sunflower production in the semi-arid and arid regions of the world. Potassium (K) application has been found effective to alleviate the influence of drought stress; however, the impact of drought stress on seed quality of sunflower has not been reported frequently. Therefore, a field experiment was performed to determine the optimum K requirement for mitigating the adverse effects of water stress and improving growth and seed quality of spring-planted sunflower. Sunflower plants were exposed to water stress at different growth stages, i.e., Io = no stress (normal irrigation), I1 = pre-anthesisi stress (irrigation skipped at pre-anthesis stage), I2 = anthesis stress (irrigation skipped at anthesis stage) and I3 = post-anthesis stress (irrigation skipped at post-anthesis stage). Potassium was applied at four different rates, i.e., Ko = 0, K1 = 50, K2 = 100 and K3 = 150 kg ha-1. The results revealed that water stress at pre- and post-anthesis stages significantly reduced plant height, head diameter, number of achenes, oleic acid contents, and phosphorus (P) uptake. However, pre-anthesis stress improved linoleic acid contents. Treatment IoK3 (stress-free with 150 kg ha-1 K) was optimum combination for 1000-achene weight, biological and achene yields, oil contents, protein contents, and N and P uptake. Results indicated that a higher amount of K and irrigation resulted in higher yield, whereas yield and yield components decreased with early-stage water stress. Nevertheless, potassium application lowered the impacts of waters stress compared to no application. Keeping in view these results, it is recommended that sunflower must be supplied 150 kg ha-1 K in arid and semi-arid regions to achieve higher yield and better seed quality.

Diallel Analysis for Area, Chlorophyll and Temperature of Flag Leaf in Bread Wheat under Well Watered and Drought Stress Conditions

To study genetic analysis of some physiological traits of drought stress in wheat using diallel techniques, an experiment was performed on ten bread wheat genotypes as parents and their 45 F1 hybrids in a randomized complete block design with three replicates under well-watered and drought stress conditions at the Research Farm of Faculty of Agriculture, Sohag University, Egypt during season of 2018/19. The results showed significant differences between the genotypes (G), Parents (P), F1 crosses, P vs. F1, GCA and SCA under well-watered and drought stress in the flag leaf area (FLA), flag leaf chlorophyll content (FLCC) and flag leaf temperature (FLT), except FLCC for F1 crosses exhibited insignificant differences. The significant differences were found in the interaction of SCA × Env., in all studied traits and GCA × Env., for FLT., indicating the involvement of both additive and dominance gene action in their inheritance. The most desirable heterotic effects were considered as the largest positive heterosis estimates for FLA and FLCC, and the lowest negative for FLT. The parent numbers P9, P8 and P3 were the best general combiner for FLA under normal irrigation and drought stress. While the parents P2, P7 and P9 were the best general combiner for FLCC, under normal irrigation and (P1, P2 and P3) under drought stress. Therefor the parents P1, P4 and P5 were the best general combiner for FLT under normal irrigation, also the P3, P4 and P5 were the best general combiner for FLT under drought stress conditions. Under normal irrigation and drought stress conditions as well as the combined data, the additive genetic components of variation (VA) in F1 ’s was much greater than dominance component (VD), as expressed by the (VA/VD) ratio which was more than unity for the FLA, and FLT under normal irrigation and their combined. This indicates that the additive gene effects in F1 crosses are more important than dominance and plays the major role in the inheritance of these studied traits.

Genetic parameters estimation for some wild wheat species and their F1 hybrids grown in different regions of Saudi Arabia

Wheat (Triticum aestivum L.) is the most important crop for human nutrition that underpins the food safety of Saudi Arabia. The investigation here was to determine heterosis effects using different genetic methods: heterosis over better, mid parents, the genetic advance, and genotype, phenotypic coefficient of variation for estimation some traits among six wheat landraces and their F1 hybrids. In 2019, these landraces were sown using hand and after 100 days, the emasculation and crossing were made among these six landraces using hand emasculation of anthers. In 2020, seeds for these genotypes (six wheat landraces and their F1) were sown under normal irrigation accordingly done in 2019. The results showed that the most important parent was Mabia resulted with the highest value in number of tiller/ plant, 1,000-grain weight, and fresh shoot weight. The highest value of plant height among six parents was Naqra while highest value at the same trait among F1 hybrids was P3 XP6. The estimations of heterosis showed that out of 15 crosses, one cross (P1XP5) was significantly better yield than all crosses for these four traits. The genotype coefficient of variation (GCV) ranged from 12.5% to 8.7% while phenotypic coefficient of variation ranged from 17.7% to 11.3%. The correlationcoefficients was found between fresh shoot weight and number of tiller and plant height and umber of tiller. Wild wheat still serve as a source of useful germplasm with proven adaption and productivity and thus assembles of the wild wheat assortments are the initial step of breeding program.

Drought Stress Alleviation by Potassium-Nitrate-Containing Chitosan/Montmorillonite Microparticles Confers Changes in Spinacia oleracea L.

Drought and low amounts of mineral nutrients in the soil are the two leading global constraints in arid and semiarid regions. Their detrimental effects on soils and crops can be alleviated by applying controlled release and biodegradable fertilizers to better and sustain the crops. On a global scale, spinach (Spinacia oleracea L.) is an essential leafy green vegetable that is biologically considered a reliable source of essential nutrients and minerals for human health. A comprehensive approach is needed to manage water stress to mitigate the impacts of stress-caused damage and to examine this for better and increased plant production. An experiment was conducted using potassium-nitrate-containing chitosan/montmorillonite microparticles (150 mg) under mild and severe drought stress (MDS: 50% and SDS: 35% FC, respectively). The treatments include control (no KNO3 and 70% FC as normal irrigation (NI)), KNO3 + NI, 50% FC as mild drought stress (MDS), KNO3 + MDS, 35% FC as severe drought stress (SDS) and KNO3 + SDS. Results revealed that drought stress decreased all studied physiological parameters and increased oxidative stress indicators in spinach. Applying KN significantly increased root (122%) and shoot length (4%), shoot fresh weight (32%) and shoot dry weight (71%), chlorophyll a (88%), carotenoids (39%), total soluble proteins (50%), soluble sugars (51%), potassium (80%), and phosphorous (32%) concentrations over No KN at severe drought. While stress indicators, like glycine betaine, malondialdehyde, hydrogen peroxide, electrolyte leakage, peroxidase, superoxide dismutase, and ascorbic acid levels, were increased in stress. Treatment KN was proved efficient and effective in improving spinach physiological status in both MDS and SDS.

English

Drought is one of the most damaging environmental stresses, which decreases the achene yield of sunflower (Helianthus annuus L.). The objectives of our experimentations were to determine the type of gene action in sunflower under drought stress, for the identification of the lines with higher achene yield for purpose of developing hybrid with higher achene yield. Thirty-two single cross hybrids from 12 inbred lines were developed through line × tester mating design through crossing 8 drought tolerant inbred lines with 4 drought susceptible lines. The evaluation experiment was performed under an alpha (0,1) lattice incomplete block design with three replications. The achene yield related traits like DF, DM, PH, NL/P, HD, SG, AY/P and TAW were evaluated under normal irrigation and drought stress conditions. Values of degree of dominance greater than one indicating that traits were under the control of dominant genetic effect. Based on GCA effects, L1 proved good combiner for early flowering, maturity and short stature; while L6 was a good combiner for NL/P, HD and AY/P while L8 for HD, SG, AY/P and TAW under drought stress condition. Based on SCA effects, Hybrid 20 was found a good SCA combiner for early flowering, early maturity, short stature, higher HD, AY/P and TAW under normal as well as drought stress conditions. It was suggested form our study that the lines L1, L6 and L8 can be further used to develop drought tolerant hybrids for higher yield and L5 × L12 (Hy 20) was proposed for general cultivation in irrigated as well as rainfed areas of Pakistan.

Estimation of Combining Ability and Heterosis for Wheat Yield and Its Components under Water Stress Conditions

DROUGHT is a worldwide problem which controls the crop productivity. Six Egyptian bread wheat varieties were crossed in a 6x6 half diallel in 2018/19 season. Parents and their fifteen F1 crosses were evaluated under normal irrigation (N), mid water stress (MS) and severe water stress (SS) during 2019/20 in three field experiments. Results showed that the analysis of variance were significant for all the studied traits. The highest mean values were recorded under all irrigation treatments as well as the combined analysis with the crosses P1x P2, P1 x P3, P1 x P5, P2 x P3, P3 x P5 and P5 x P6 for grain yield per plant. Mean squares for both general (GCA) and specific (SCA) combining ability estimates were highly significant for all studied traits. GCA/SCA ratio was greater than unity for most traits. The parental P1 exhibited positive and significant GCA effects for number of kernels per spike, grain yield per spike and grain yield per plant. The highest desirable SCA effects were obtained with the crosses P3 x P5 and P4 x P5 for grain yield per plant under stresses conditions. Positive significant heterosis were detected by the crosses P1 x P3, P2 x P3, P3 x P5, P4 x P5 and P5 x P6 for number of spikes per plant, number of kernels per spike, grain yield per spike, 1000-grain weight and grain yield per plant at N, MS, SS conditions and the combined data.

Molecular markers and GGE biplot analysis for selecting higher‐yield and drought‐tolerant maize hybrids

AbstractImproving maize (Zea mays L.) genotypes for higher productivity and tolerance to drought stress depends mainly on physiological and molecular markers. Therefore, this study aims at breeding maize for drought tolerance and high potentiality by selection based on molecular markers, photosynthetic parameters; and easy graphic methods that help in selecting elite genotypes across diverse environments. An 8 × 8 half diallel analysis was used at two locations involving drought and normal irrigation treatments to study parental genetic diversity (GD) and combining ability (general combing ability [GCA] and specific combining ability [SCA]) in F1 of maize. Fingerprinting of parents was made using simple sequence repeat (SSR) markers. Fifty‐eight alleles were ranged from two to five alleles per locus with an average of 0.63 alleles per locus. The average of polymorphic information content (PIC) was 0.63. Cuvette temperature (oc) was lowest by the cross L14 × L36. The cross L8 × L34 expresses the highest value for Quantum sensor (μmol m–2 s–1), net CO2 assimilation rate and chlorophyll content. As for leaf diffusive resistance (LDR) four crosses exhibited significant desirable LDR values. Concerning rate of leaf transpiration (LTR) (μg cm−2 S−1) the cross (L5 × L104) gave the lowest value. Most hybrids exhibited desirable values for drought susceptibility index. For grain yield plant–1, five F1 crosses, that is, L5 × L34, L8 × L14, L8 × L14, L30 × L104, and L36 × L104 expressed the most desirable SCA effects. These crosses are promising in maize breeding programs. Based on GGE biplot analysis, genotype nos. 8 and 10 exhibited the highest grain yield plant−1 and ranked the first across all environments.

Evaluation of synthetic canal lining materials in South Texas over 18 years—Final results and conclusions*

AbstractSince 1999, irrigation districts in Hidalgo, Cameron, Willacy, and Maverick Counties in South Texas have been experimenting with an assortment of canal lining materials installed in about 40 km of earthen and concrete canals. In 2005, the Texas A&M AgriLife Extension Service initiated a programme to track the long‐term effectiveness and durability of these materials and to document installation and maintenance procedures which will help ensure good performance. Each lining project was periodically inspected to document the effects of such factors as weather, animals, intentional and unintentional vandalism, farm machinery traffic, and normal irrigation district operational and maintenance activities. Evaluation forms were developed to document observations during inspections. The forms consisted of three elements: a general project description, a district operations questionnaire, and a field observation and rating survey. During inspection, the size and locations of holes and tares in the lining materials were identified, along with the most probable causes of the problems found. In this paper, we summarize results and provide recommendations on liner installation and maintenance obtained from evaluations which span about 18 years of material age. The lining systems which performed the best were synthetic liners overlaid with concrete.

The effect of drought stress of sorghum grains on the textural features evaluated using machine learning

This study aimed to determine the discriminatory power of textural features to differentiate the sorghum grains subjected to normal, mild deficit, and severe deficit irrigation. The studies were carried out with the use of image processing, discrimination analysis, analysis of variance and cluster analysis using the selected texture parameters calculate for images from individual color channels L, a, b, R, G, B, U, V, S, X, Y and Z. The results indicated that different levels of irrigation can discriminate the sorghum grain with an accuracy of up to about 100%. Most of the genotypes for each level of irrigation were different in the terms of values of textural features and formed separate homogeneous groups. Drought is one of the limiting factors contributing to a decrease in sorghum grain productivity and nutritional quality, especially when it is cultivated in a marginal area. Therefore, low-quality grains produced under water stress should be recognized before they enter into the food and feed chain. The application of image analysis based on textures of sorghum grain images proved to be useful for the discrimination of sorghum grains subjected to drought stress. The applied procedure provided the fast, objective results that may be applied in practice for screening distinguishing the sorghum grains with different irrigation levels.

Character Association and Path Coefficient Analysis of Certain Biometrical Traits among Fenugreek Genotypes under Different Environmental Conditions

Background: Fenugreek is grown under various agro-climatic conditions of the world as well as in India. However, overall yield and quality depends upon various quantitative characters that exist during crop growth period. Therefore, this study aimed to find out the character association and path coefficient analysis among the seed yield and yield contributing characters in fenugreek genotype. Methods: Thirty genotypes were sown with three replications under two environments namely normal (E1) and limited (E2) irrigation conditions during Rabi season 2019-20. The experiment was laid down in RBD. Result: The genotypic and phenotypic correlations were exhibited significantly positive for number of pods per plant (0.765, 0.725 and 0.670, 0.651), number of seeds per pod (0.705, 0.650 and 0.666, 0.640) and pod length (0.376, 0.348 and 0.351, 0.327) with seed yield per plant in both the environments i.e. E1 and E2. The highest direct effect on seed yield per plant was observed for number of pods per plant (0.693, 0.602 and 1.030, 0.754), number of seed per pod (0.396, 0.378 and 0.490, 0.421) and test weight (0.338, 0.304 and 0.405, 0.368) at genotypic and phenotypic levels in both environments i.e. E1 and E2.

Substrate Stratification: Layering Unique Substrates within a Container Increases Resource Efficiency without Impacting Growth of Shrub Rose

Nurseries rely on soilless substrates to provide suitable growing media for container grown crops. These soilless substrates have been developed to readily drain water to prevent issues with waterlogging and associated soil-borne disease. A negative consequence of high porosity and subsequent drainage throughout the container profile is the required high or frequent irrigation rates with poor retention of applied nutrients. Substrates with relatively high levels of moisture and nutrient retention placed on top of a coarse and freely draining substrate could further optimize water and nutrient retention, while allowing for needed gas exchange for plant establishment and growth. Containerized Red Drift® rose (Rosa ‘Meigalpio’ PP17877) plants were grown under 16 mm or 12 mm daily irrigation, utilizing a traditional pine bark substrate or stratified substrates with either a conventional bark, bark fines, or a bark–peat mixture on top of a coarse bark within a container. The stratified substrates received 20% less controlled-release fertilizer; however, the fertilizer in the stratified treatments was concentrated in the upper strata only. During the first growing phase or season, plants grown in stratified substrates outperformed those grown in conventional, non-stratified bark substrates under normal irrigation. The stratified substrates did not reduce growth under reduced irrigation regimes. Overall, crop growth was equal or superior for stratified substrates when compared to the non-stratified controls, even with a 20% reduction of fertilizer. This research suggests that stratified substrate systems can be used to reduce fertilizer and irrigation rates while producing crops of similar or superior quality to conventionally grown containerized crops.

Drought tolerance indices and path-analysis in long staple cotton genotypes (G. barbadense)

Drought stress is a serious abiotic factor adversely affects cotton yield and fiber properties. The objectives of this study were to screen several genotypes of cotton belong to Gossypium barbadense L. for drought tolerance, study drought indices, correlations, and path-coefficient analysis. Fourteen long staple cottons cultivated, and obsolete cultivars were screened for drought tolerance at normal irrigation and drought stressed experiments for two years. Mean squares indicated significant (p ≤ 0.01) differences among genotypes in separate and combined analysis. The effect of years showed significant (p≤ 0.05 to p≤ 0.01) differences in most cases. The interaction of genotypes by years were significant for all traits except few cases. The reduction % caused by drought stress in SCY/P ranged from 31.44 to 39.39 with an average of 33.93. Among ten tolerant indices STI, MP, GMP, HM and DI could be considered the best tolerant indices to detect both of tolerant and susceptible genotypes. The correlation of SCY/P under normal irrigation was high with LY/P, Lint %, NB/P, LI and BW, moderate with NS/B and upper half mean length, and low with DFF, Pressely index and negative with Micronaire reading. However, the picture was different under drought stress, in which drought affected lint rather than seeds. The direct and indirect effects of SCY/P components varied greatly under both environments, and LY/P, NB/P and NS/B should be considered as selection indices under normal irrigation, NB/P and NS/B under stress when selection practiced for SCY/P.

Grain and Oil Yields of Safflower (Carthamus Tinctorius L.) Affected By Water Deficit and Growth Regulators

Abstract In order to evaluate the effects of growth regulators on yield parameters and oil content of safflower (Carthamus tinctorius L.), a field experiment was conducted under different irrigation intervals in 2019. All plots were irrigated regularly until the seedling establishment and thereafter irrigation intervals were applied after 70, 100, 130, and 160 mm evaporation from class A pan, as normal irrigation and mild, moderate, and severe water deficits, respectively. Foliar sprays of water (control), putrescine (60 µg/L), and 24-epibrassinolide (25 µg/L) at a rate of 1,000 L/ha were applied slightly before flowering. The results revealed that means of plant biomass, grains per capitol, grains per plant, grain yield, harvest index, oil percentage, and yield were decreased under limited irrigations, but 1,000-seeds weight was only reduced under severe water deficit. However, fo-liar sprays of growth regulators, particularly putrescine, increased grains per plant, grain yield, and harvest index, leading to an improvement in oil yield per unit area under different levels of water supply. These results suggest that foliar application of putrescine is a superior treatment for improving the productivity of safflower plants under normal and stressful conditions.

Up-scaling of water saving technologies in rice cultivation under corporate social responsibility scheme

Field demonstrations were carried out in 25 locations each separately in Villupuram district of Tamilnadu for upscaling water saving technology in rice cultivation like System of Rice Intensification (SRI) and Alternate Wetting and Drying Irrigation(AWDI). The bio-metric observation data was recorded in the earmarked area in the demonstration field plot and the computed average mean data was used for analysis. In the demonstrations, the total water requirement, quantity of water required to produce one kilogram of rice and number of irrigations were significantly less in SRI compared to conventional planting system. There was water saving of 350 mm recording 29.16 percentage. Similarly, AWDI demonstrations revealed that, AWDI saved 270-350 mm more water per hectare than the normal irrigation system. Increase in the grain yields obtained with water saving made the farmers confident on these water saving technologies.

Canola Quality and Fatty Acids Composition as Influenced by Delayed Cropping and Late Season Drought Stress

To investigate the effects of drought stress and delayed planting on oil quality and fatty ‎acids composition of canola cultivars, a factorial split-plot test was conducted in a ‎randomized complete blocks design with three replications at Seed and Plant Improvement ‎Institute, Karaj, Iran for two years (‎2015-2017) ‎.Planting date at two levels of timely ‎planting (Oct. 27) and late planting (Nov. 27) and irrigation at two levels of normal ‎irrigation (control) and restricted irrigation from pod formation stage onwards were ‎considered the main factors. Canola cultivars including Kodiak, Traviata, Compass, ‎Diffusion, Mehr2, Elvise and Tassilo were the variables. The simple effects of planting date, ‎irrigation, and cultivar on all research parameters were significant. The interaction effect of ‎planting date × irrigation was significant on oil yield and oil content at the level of 5% and ‎in terms of linoleic and palmitic acids, and stomatal resistance, it was significant at the level ‎of 1%. The interaction effect of irrigation × cultivar was significant on palmitic acid, ‎glucosinolate and stomatal resistance at the level of 1%. Late season drought stress and late ‎planting dramatically reduced oil yield (58%), oil content (8%) and qualitative ‎characteristics of canola cultivars. Among the studied cultivars, Tassilo cultivar was ‎recommended for all conditions of this research with the seed yield (4407 kg ha-1), oil yield ‎‎(2007 kg ha-1), chlorophyll content (1.43 mg g-1fw), high oleic and linoleic fatty acids, as ‎well as low and standard erucic acid (0.41%) and glucosinolate (22.8 μmol g-1).‎

The effect of arbuscular mycorrhizal fungi on the phenolic compounds profile, antioxidant activity and grain yields in wheat cultivars growing under hydric stress.

Hydric stress affects the production of wheat (Triticum aestivum L.) worldwide, making some tools necessary to cope with the decrease in rainfall. A sustainable alternative is the use of arbuscular mycorrhizal fungi (AMF) as biofertilisers. Here, we analysed the effects of AMF strains adapted or non-adapted to hyper-arid conditions on the phenolic profiles and antioxidant activities of wheat grains from two cultivars with contrasting tolerance to osmotic stress (Ilustre, moderately tolerant; and Maxi, tolerant) grown with and without hydric stress. Eight phenolic compounds were detected, apigenin-C-pentoside-C-hexoside I being the most abundant and showing an increase of 80.5% when inoculated with the fungus Funneliformis mosseae (FM) obtained from Atacama Desert under normal irrigation with respect to non-mycorrhizal (NM) plants. NM treatments were associated with higher grain yields. FM showed a noticeable effect on most phenolic compounds, with an increase up to 30.2% in apigenin-C-pentoside-C-hexoside III concentration under hydric stress with respect to normal irrigation, being also responsible for high antioxidant activities such as ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) activities. Inoculation with FM adapted to hydric stress produced improvements in phenolics composition and antioxidant activities in grains from wheat plants growing under hydric stress conditions, improving their food quality and supporting the development of further studies to determine whether the use of adapted AMF could be a realistic tool to improve grain quality in a scenario of increasing hydric stress conditions. © 2021 Society of Chemical Industry.