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Wheat breeding programs are currently focusing on using non-destructive and cost-effective hyperspectral sensing tools to expeditiously and accurately phenotype large collections of genotypes. This approach is expected to accelerate the development of the abiotic stress tolerance of genotypes in breeding programs. This study aimed to assess salt tolerance in wheat genotypes using non-destructive canopy spectral reflectance measurements as an alternative to direct laborious and time-consuming phenological selection criteria. Eight wheat genotypes and sixteen F8 RILs were tested under 150 mM NaCl in real field conditions for two years. Fourteen spectral reflectance indices (SRIs) were calculated from the spectral data, including vegetation SRIs and water SRIs. The effectiveness of these indices in assessing salt tolerance was compared with four morpho-physiological traits using genetic parameters, SSR markers, the Mantel test, hierarchical clustering heatmaps, stepwise multiple linear regression, and principal component analysis (PCA). The results showed significant differences (p ≤ 0.001) among RILs/cultivars for both traits and SRIs. The heritability, genetic gain, and genotypic and phenotypic coefficients of variability for most SRIs were comparable to those of measured traits. The SRIs effectively differentiated between salt-tolerant and sensitive genotypes and exhibited strong correlations with SSR markers (R2 = 0.56–0.89), similar to the measured traits and allelic data of 34 SSRs. A strong correlation (r = 0.27, p < 0.0001) was found between the similarity coefficients of SRIs and SSR data, which was higher than that between measured traits and SSR data (r = 0.20, p < 0.0003) based on the Mantel test. The PCA indicated that all vegetation SRIs and most water SRIs were grouped with measured traits in a positive direction and effectively identified the salt-tolerant RILs/cultivars. The PLSR models, which were based on all SRIs, accurately and robustly estimated the various morpho-physiological traits compared to using individual SRIs. The study suggests that various SRIs can be integrated with PLSR in wheat breeding programs as a cost-effective and non-destructive tool for phenotyping and screening large wheat populations for salt tolerance in a short time frame. This approach can replace the need for traditional morpho-physiological traits and accelerate the development of salt-tolerant wheat genotypes. [ABSTRACT FROM AUTHOR]

Heat as an abiotic stress significantly impairs the sustainable productivity of wheat (Triticum aestivum L.). To determine the tolerance of genotypes to heat stress, a comprehensive approach should be used that integrates simultaneous phenotyping and genotyping analyses. The aim of this study is to identify local heat-tolerant genotypes using simple sequence repeat (SSR) markers and evaluate the selected genotypes under field conditions for their tolerance to heat stress. Of the 12 SSR markers that showed polymorphism, eight were associated with six important traits. The use of hierarchical cluster analysis (HC) based on SSR markers led to the identification of 13 genotypes that showed varying results and were grouped into three distinct heat tolerance classes: tolerant (T), moderately tolerant (MT), and sensitive (S). The results showed that heat stress had a significant effect on 19 traits under this study, with significant variation in tolerance to heat stress between genotypes. The tolerant genotypes exhibited a range of average thousand-kernel weight (TKW) values between 40.56 and 44.85, while the sensitive genotype (Yecora Rojo) had an average TKW of 35.45. Furthermore, the tolerant genotypes showed two to three times higher levels of antioxidants compared to the sensitive genotypes when exposed to heat stress. Among the traits analyzed, six showed a favorable combination of high heritability (>60%) and genetic gain (>20%). Through the integration of principal component analysis and stepwise multiple linear regression, it was determined that six traits (grain yield, 1000-kernel weight, plant height, intercellular carbon dioxide, flag leaf area, and grain filling duration) revealed differences between the 13 genotypes. HC analysis of the six traits resulted in the same division of genotypes into three main categories as observed in an HC analysis based on SSR markers. It is worth noting that Saudi wheat, including KSU106, KSU105, and KSU115 as local genotypes, in addition to the 16HTWYT-22 genotype, showed higher heat tolerance compared to the other genotypes tested, indicating its potential suitability for agriculture in Saudi Arabia. These results contribute to breeding programs focused on developing heat-tolerant wheat varieties and accelerate progress in wheat productivity improvement programs. [ABSTRACT FROM AUTHOR]

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts' biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant. [ABSTRACT FROM AUTHOR]

Drought stress is one of the biggest hardships in wheat cultivation because of the strong negative relationship between water deficit and crop yields owing to a lower grain weight, a shorter grain-filling period, a slower grain-filling rate, and reduced grain quality. Genotype–environment interaction (GEN:ENV) generates hardships in selecting wheat genotypes and ideotypes due to biased genetic estimates. Diverse strategies have been proposed to respond to the urgent need for concurrent improvements in yield performance and stability. This study's purpose was to appraise genetic variation and GEN:ENV effects on yield and yield components to discover drought-stress-tolerant genotypes and ideotypes. This study evaluated 20 genotypes in three consecutive seasons under non-stressful and drought-stress conditions in a total of six ENVs. The broad-sense heritability ranged from 0.54 to 0.82 based on expected mean squares and ranged from 0.60 to 0.90 based on plot mean, but in the other three ways, it was usually greater than 0.90. The high values of ( σ gen : e n v 2 ) revealed the effect that broad-sense heritability has on the expression of traits. G01, G03, G06, G07, G08, G10, G12, G13, G16, G17, and G18 were stable genotypes for grain yield (GY), according to additive main effects and a multiplicative interaction biplot for the six ENVs. Based on scores in the weighted average of absolute scores biplot (WAASB), G02, G04, G05, G08, G10, and G18 were selected as stable and high-performance for GY, and they were all selected as the best genotype groups using the WAASB-GY superiority index. From the results obtained from principal component analysis and hierarchical clustering and from the tolerance discrimination indices, G02, G04, G05, G18, and G19 are genotypes that produce a suitable yield under non-stressful and drought-stress conditions. In essence, combining approaches that take into consideration stability and high performance can contribute significantly to enhancing the reliability of recommendations for novel wheat genotypes. [ABSTRACT FROM AUTHOR]

Barley is indeed a versatile cereal crop, valued for its uses in food, animal feed, and increasingly in biofuel production. As interest grows in developing new barley genotypes that are better adapted to diverse environmental conditions and production systems, integrating agro-morphological evaluations with molecular marker analyses in barley breeding programs is essential for developing new genotypes. It is necessary to explore the genetic diversity of those germplasm to predicate their responses to targeted environments and regions. The current study explored the phenotypic and genotypic relations among Saudi advanced germplasm to facilitate the development of superior barley cultivars suitable for desert environments. Molecular microsatellites (SSR) markers revealed considerable wide genetic variation among Saudi germplasm and checks. Population structure analyses revealed four main groups. Those groups were validated using similarity analyses and coefficients. As well, principal components analysis (PCA) and heat map analyses separated the studied genotypes into four main groups. The improved Saudi germplasm, selected from the barley breeding program, revealed considerably wide genetic and phenotypic diversities, indicating the feasibility of selection to improve for semi-arid conditions. The improved line KSU-BR-C/G-2 had the highest grain yield and harvest index in the first season. Rihana/Lignee was followed by the KSU-BR-C/G-2 genotype, with a grain yield averaging 6734.07 (kg ha−1), in the first season. KSU-BR-88-29-10 yielded 20,000 kg ha−1 for biomass yield. In the second year, KSU-BR-30-7 had the highest biomass yield, with 27,037.04 kg ha−1. [ABSTRACT FROM AUTHOR]

While Egypt's canola production per unit area has recently grown, productivity remains low, necessitating increased productivity. Hydrogels are water-absorbent polymer compounds that can optimize irrigation schedules by increasing the soil's ability to retain water. Accordingly, two field experiments were conducted to examine hydrogel application to sandy soil on canola growth, biochemical aspects, yield, yield traits, and nutritional quality of yielded seeds grown under water deficit stress conditions. The experiments were conducted by arranging a split-plot layout in a randomized complete block design (RCBD) with three times replications of each treatment. While water stress at 75% or 50% of crop evapotranspiration (ETc) lowered chlorophyll a, chlorophyll b, carotenoids, and total pigments content, indole-3-acetic acid, plant development, seed yield, and oil and total carbohydrates of seed yield, hydrogel treatment enhanced all of the traits mentioned above. Furthermore, hydrogel enhanced to gather compatible solutes (proline, amino acids, total soluble sugars), phenolics content in leaves, seed protein, and crop water productivity, which increased while the plants were under water stress. The results revealed that the full irrigation (100%ETc) along with hydrogel compared to water-stressed (50%ETc) led to enhanced seed yield (kg ha), Oil (%), and Total carbohydrates (%) of rapeseed by 57.1%, 11.1% and 15.7%, respectively. Likewise, under water-stressed plots with hydrogel exhibited enhancement by 10.0%, 3.2% and 5.1% in seed yield (kg ha), oil (%), and total carbohydrates (%) of rapeseed by 57.1%, 11.1% and 15.7%, respectively compared to control. As a result, the use of hydrogel polymer will be a viable and practical solution for increasing agricultural output under water deficit stress situations. [ABSTRACT FROM AUTHOR]

The low solubility and enhanced fixation of zinc (Zn) in semi-arid and dry climates limits Zn uptake in plants. Zn deficiency in soil impairs crop production and human health, necessitating agricultural biofortification. A pot experiment was conducted to evaluate the effect of Zn and various types of manure on the Zn biofortification of lentils. The treatments, consisting of a control (Con), normal manure (NM), composted manure (CM), and acidified manure (AM), were applied under saline soil (EC 8.00 dS m−1) and non-saline soil (EC 1.48 dS m−1) conditions along with two levels of Zn, including Zn at 0 kg ha−1 (native soil Zn = 2.2 mg kg−1) and Zn at 25 kg ha−1 (62.2 mg Zn kg−1 soil was achieved). The AM was prepared by adding sulfur and sulfur-oxidizing bacteria to the composted manure. All the manures were applied at 1% (w/w), and ZnSO4 (33% Zn) was used as a Zn source. Lentil variety Masoor 2021 was cultivated as a test crop in five replications of each treatment arranged in a completely randomized design. Applying AM with Zn considerably increased the lentils' growth, yield, and Zn content under saline and non-saline conditions. Under non-saline soils, the treatment of AM + Zn significantly promoted the Zn content in the root (132.5%), shoot (91.7%), grain (49.1%), root length (79.7%), plant height (33.7%), and SPAD value (29.9%). Under saline conditions, application of AM + Zn promoted uptake of Zn in the root (218.5%), Zn content in the shoot (175.7%), Zn accumulation in the grain (107.7%), root length (109.7%), plant height (37.8%), and SPAD value (52.8%) compared to the control. According to the results, lentils should be grown with AM and Zn to increase their growth, yield, and Zn content significantly. This is a cost-effective and sustainable way to combat Zn deficiency in lentils. [ABSTRACT FROM AUTHOR]

Adequate soil moisture around the root zone of the crops is essential for optimal plant growth and productivity throughout the crop season, whereas excessive as well as deficient moisture is usually detrimental. A field experiment was conducted on cotton (Gossipium hirsuttum) with three water regimes (viz. well-watered (control); rainfed after one post-sowing irrigation (1-POSI) and rainfed after two post-sowing irrigations (2-POSI)) in main plots and application of eight osmoprotectants in sub plots of Split plot design to quantify the loss of seed cotton yield (SCY) under high and mild moisture stress. The DSSAT-CROPGRO-cotton model was calibrated to validate the response of cotton crop to water stress. Results elucidated that in comparison of well watered (control) crop, 1-POSI and 2-POSI reduced plant height by 13.5-28.4% and lower leaf area index (LAI) by 21.6-37.6%. Pooled analysis revealed that SCY under control was higher by 1,127 kg ha-1 over 1-POSI and 597 kg ha-1 than 2-POSI. The DSSAT-CROPGRO-cotton model fairly simulated the cotton yield as evidenced by good accuracy (d-stat = 0.92) along with lower root mean square error (RMSE) of =183.2 kg ha-1; mean absolute percent error (MAPE) =6.5% under different irrigation levels. Similarly, simulated and observed biomass also exhibited good agreement with =0.98 d-stat; =533.7 kg ha-1 RMSE; and =4.6% MAPE. The model accurately simulated the periodical LAI, biomass and soil water dynamics as affected by varying water regimes in conformity with periodical observations. Both the experimental and the simulated results confirmed the decline of SCY with any degree of water stress. Thus, a well calibrated DSSAT-CROPGROcotton model may be successfully used for estimating the crop performance under varying hydro-climatic conditions. [ABSTRACT FROM AUTHOR]

Drought is one of the critical limitations to agricultural soils and crop plants. Scarcity of water is increasing due to climate change that lead to increasing threats to global food security. Therefore, ecofriendly and cost effective strategies are highly desirable for mitigating drought stress along with sustainable and smart agricultural production. The aim of the study was to mitigate DS using seed priming and exogenous supplementation of ß-aminobutyric acid (BABA) in linseed (Linum usitatissimum L.). Different doses (0, 50, 100 and 150 µM) of BABA were used for seed priming agent and foliar spraying under three soil moisture levels viz., 25% (SM25), 45% (SM45) and 65% (SM65). The response variables of both experiments included different agro-botanical traits and oxidative stress indicators such as melondialdehyde content, free proline accumulation, and antioxidant defense in plants. The linseed plants showed water stress at SM25 that reduced plant height, number of branches per plant, time taken to flower initiation and heading, and root and shoot dry weights. Additionally, the number of capsules and seeds per capsule showed a significant decline at SM25, which led to a drastic reduction in 100-seed weight yield in linseed plants in both experiments. However, seed priming and foliar supplementation with of BABA (50-100 µM) significantly improved these morpho-agronomical attributes in linseed plants under DS. The results revealed that the BABA was fully active in linseed plants at SM25. Interestingly, the combination of SM25 with BABA significantly improved the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity, which significantly enhanced DS tolerance in linseed plants. These findings might be useful to oil seed breeders and farmers linseed for breeding program in linseed plants as well as sustainable agricultural production of oil seed crop plants. [ABSTRACT FROM AUTHOR]

One hundred twenty-five endophytic microorganisms were isolated from the roots, stems, and leaves of four prominent rice cultivars growing in temperate regions. Their potential to combat rice blast disease and promote plant growth was investigated. The dual culture tests highlighted the strong antagonistic activity of five fungal (ranging from 89%-70%) and five bacterial (72%-61%) endophytes. Subsequent examination focused on volatile compounds produced by selected isolates to counter the blast pathogen. Among these, the highest chitinase (13.76 µg mL-1) and siderophore (56.64%), was exhibited by Aspergillus flavus, and the highest HCN production was shown by Stenotrophomonas maltophilia (36.15 µM mL-1). In terms of growth promotion traits, Aspergillus flavus and Enterobacter cloacae excelled in activities viz, phosphorous solubilization, ammonia production, auxin and gibberellic acid production, and nitrogen fixation. The Identity of these endophytes was confirmed through molecular analysis as Trichoderma afroharzianum, Trichoderma harzianum, Penicillium rubens, Aspergillus flavus, Stenotrophomonas rhizophila, Stenotrophomonas maltophilia, Bacillus cereus, Enterobacter cloacae, and Bacillus licheniformis. Under greenhouse conditions, the highest disease control was shown by isolate Bacillus licheniformis and A. flavus with an inhibition of 79%, followed by S. rhizophila (77%) and T. afroharzianum (73%). The overall results of this study showed that Bacillus licheniformis and Stenotrophomonas rhizophila have great potential to be used as bio-stimulant and biocontrol agents to manage rice blast disease. [ABSTRACT FROM AUTHOR]