Effects of homobrassinolide application on plant metabolism and grain yield under irrigated and moisture-stress conditions of two wheat varieties

The objectives of the present study were to evaluate heterosis for grain yield and yield components in durum wheat, and to assess the prediction potential of amplified fragment length polymorphism (AFLP) based and agronomic trait based genetic distances (GD and MD, respectively) to F1 performance, mid parent heterosis (MPH), and specific combining ability effects (SCA) under well-watered and moisture stress conditions. Six parental genotypes with different responses to moisture stress and their 15 F1 crosses were evaluated for their responses to moisture stress conditions in a glasshouse. Some cross combinations showed significant MPH for grain yield and yield components. The expression of heterosis for grain yield was greater under moisture stress conditions than under well-watered conditions. Cluster analysis of the parental lines based on agronomic performance under stress conditions was similar to cluster analysis result based on AFLP marker profiles. F1 performance was strongly correlated to both SCA effects and MPH under both stress and well water conditions. The correlation between SCA and MPH was very high under both treatment conditions for all traits. Correlation between GD and MD was significant only under stress conditions. Positive correlation was found only for the association between GD v. F1 performance and GD v. SCA effects for harvest index (HI) under well-watered conditions. None of the correlations between MD and SCA effects were significant. The absence of association between GD and heterosis for yield and most agronomic traits implied that heterozygosity per se diversity is not a good predictor of heterosis or F1 performance under both well-watered and stressed conditions.

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The Drought Effect on Morphophysiological Parameters and Crop Performance Indicators of the Studied Local Wheat Genotypes

Bulletin of Science and Practice ◽

10.33619/2414-2948/71/06 ◽

2021 ◽

Vol 7 (10) ◽

pp. 45-56

Author(s):

T. Tamrazov

Keyword(s):

Grain Yield ◽

Triticum Aestivum L ◽

Base Station ◽

Stress Conditions ◽

Wheat Varieties ◽

Drought Effect ◽

Plant Yield ◽

Wheat Genotypes ◽

Relative Water ◽

Experimental Base

Drought stress is the most important factor and an increasingly serious problem limiting the growth of wheat (Triticum aestivum L. / Triticum durum) in the world. Wheat possesses physiological mechanisms that allow it to adapt to the stress of drought and can vary depending on the genotype. The studies were carried out on wheat genotypes at the Absheron Experimental Base Station of the Azerbaijan Scientific Research Institute of Crop Husbandry. The experiment was designed in a factorial design with two treatments (irrigated and non-irrigated) and three repetitions during the 2020–2021 harvest season. Analysis of variance revealed significant differences between treatments and between varieties. The treatment × cultivar interaction was also significant for all traits, with the exception of grain per plant yield. Significant interactions showed that varieties performed differently under stressful conditions, but consistently with respect to grain yield. The studied varieties Giymatly-2/17, Gunashly and Tale-38 showed a minimal decrease in physiological characteristics, as well as in yield characteristics under stress during flowering, however, a decrease from low to high was observed under stress conditions compared with no stress. Correlations between morphological, physiological, and morphophysiological traits such as plant height, number of grains per ear, seed index, grain yield per plant, yield index, relative water content, stomatal conductance, leaf area and ear fertility have generally been reliable indicators for screening for drought tolerant wheat varieties and potentially higher yields. In addition, it is observed that improvement in any of these traits will lead to an increase in grain yield under water stress conditions.

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Identification of effective Rhizobium isolate(s) for efficient symbiosis with soybean under moisture stress conditions

10.37281/drcsf/2.2.4 ◽

2021 ◽

pp. 116-121

Keyword(s):

Grain Yield ◽

N Uptake ◽

Dry Weight ◽

Moisture Stress ◽

Stress Conditions ◽

Nitrogen Accumulation ◽

Shoot Dry Weight ◽

Rhizobium Isolate ◽

Phosphorus Accumulation ◽

Physiological Tests

The objective of the paper is to observe the effectiveness of Bradyrhizobial species on symbiosis with soybean under moisture stress conditions. In physiological tests, treatment T3: B. daqingense (under irrigated condition) showed significant amount of leghaemoglobin content (1.82 mg). Proline content was recorded highest (2.8 mg g-1 seed) in T8 B. liaoningense in stress. Highest chlorophyll content (1.84 mg/LFW) was recorded in T4 B. liaoningense under irrigated condition. The highest N-uptake in plant shoot, root and grain was obtained in B. daqingense under irrigated condition. Similarly, highest was obtained in in treatment T3 B. daqingense under irrigated condition. At R8 stage, grain yield was significantly highest (6.48 g) in treatment T3 (B. daqingense under irrigated condition). In both irrigated and moisture stress conditions bradyrhizobial strains B. daqingense (treatment T3 and Treatment T7) were most effective in terms of nitrogen fixation, nitrogen accumulation, phosphorus accumulation, shoot dry weight, root dry weight and grain yield as compared to the other treatments.

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Variation in water use and transpiration efficiency among durum wheat genotypes grown under moisture stress and non-stress conditions

The Journal of Agricultural Science ◽

10.1017/s0021859603003356 ◽

2003 ◽

Vol 141 (1) ◽

pp. 31-41 ◽

Cited By ~ 10

Author(s):

K. F. SOLOMON ◽

M. T. LABUSCHAGNE

Keyword(s):

Grain Yield ◽

Durum Wheat ◽

Water Use ◽

Harvest Index ◽

Moisture Stress ◽

Stress Conditions ◽

Transpiration Efficiency ◽

High Positive Correlation ◽

Wheat Genotypes ◽

Selection For

Durum wheat genotypes with different responses to moisture stress were studied in a glasshouse under moisture stress and non-stress conditions to investigate differences in water use and transpiration efficiency and interrelationships among water use and transpiration efficiency and associated traits. Significantly high genotypic variability in the cumulative amount of water used before (ETba) and after (ETpa) anthesis was observed. Susceptible genotypes used higher amounts of water before anthesis and lower amounts after anthesis. In contrast, tolerant genotypes used a higher proportion of water during the post-anthesis period. Significantly high variability among the genotypes was observed for various measures of water use and transpiration efficiency, total dry matter and harvest index. Ranking of cultivars for water use efficiency based on grain yield (WUEG) and transpiration efficiency based on grain yield was consistent with ranking of cultivars for drought susceptibility indices. Drought susceptibility index was significantly but negatively correlated with harvest index, WUEG and grain yield. However, it was positively and significantly correlated with the ETba[ratio ]ETpa ratio. A high positive correlation of WUEG with harvest index and grain yield with harvest index was found. It was concluded that selection for lower ETba[ratio ]ETpa ratios up to about 0·8 could indirectly lead to improved WUEG and HI, hence improved grain yield. Selection for increased WUEG and/or grain yield would increase yield in water-limited environments.

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Performance of Dry-Seeded Rice Genotypes under Varied Soil Moisture Regimes and Foliar-Applied Hormones

Plants ◽

10.3390/plants9040539 ◽

2020 ◽

Vol 9 (4) ◽

pp. 539

Author(s):

Rajinder Pal ◽

Gulshan Mahajan ◽

Virender Sardana ◽

Bavita Asthir ◽

Bhagirath Singh Chauhan

Keyword(s):

Soil Moisture ◽

Grain Yield ◽

Plant Hormones ◽

Foliar Application ◽

Moisture Stress ◽

Stress Conditions ◽

Stay Green ◽

Moisture Regimes ◽

Rice Genotypes ◽

Sink Size

Plant hormones influence various physiological processes during the growth and development of plants, but their critical roles in influencing yield and antioxidant activities in dry-seeded rice (DSR) have not been adequately explored. This study aims to analyze the performance and antioxidant activity of contrasting genotypes of DSR in response to soil moisture regimes and foliar-applied hormones. The study comprised sixteen treatments that were evaluated under field conditions as per split-plot design in three replications. Treatments comprised combinations of two soil moisture tension regimes (10 kPa and 20 kPa) and two genotypes (PR-111, non-stay-green type and PR-123, stay-green type) applied to the main plots and foliar application of three hormones (gibberellic acid (GA3) 40 mg kg−1, abscisic acid (ABA) 20 mg kg−1, and cytokinin (CK) 40 mg kg−1)) and a control (unsprayed) to subplots. The non-stay-green genotype (PR-111) resulted in 34.6% more grain yield (6.48 t ha−1) than the stay-green genotype (PR-123) at the lower soil moisture tension regime (SMTR) (10 kPa) due to the increased number of filled grains per panicle and improvement in harvest index (HI). At the higher SMTR (20 kPa), the stay-green genotype (PR-123) produced 26.4% more grain yield (5.21 t ha−1) than non-stay green genotype (4.12 t ha−1) and showed enhanced superoxide dismutase (SOD) and peroxide dismutase (POD) activity that may have contributed in maintaining sink size through improved chlorophyll content. Grain yield (6.35 t ha−1) with foliar-applied GA3 (40 mg kg−1) at SMTR of 10 kPa was higher by 12.2% and 24.0% than with foliar-applied ABA (20 mg kg−1) and unsprayed treatments, respectively. Irrigation application at SMTR of 20 kPa and foliar application of ABA gave 24.1% higher grain yield (5.15 t ha−1) than the unsprayed treatment, but it was similar to foliar-applied GA3 and CK. This study implied that the stay-green genotype (PR-123) was more suitable under moisture stress conditions (20 kPa) in DSR, as it maintained sink size even under moisture stress conditions by improving dry matter translocation and enhancing SOD and POD activity. The study suggests the need to find out the endogenous level of these plant hormones in rice genotypes under a range of water regimes to develop high yielding and water use efficient genotypes of DSR.

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