Evaluation of heterosis and its association among morpho-physiological traits of ten wheat genotypes under water stress

The physiological and morphological responses to water stress induced by polyethylene glycol (PEG) or by withholding water were investigated in Aegilops biuncialis Vis. genotypes differing in the annual rainfall of their habitat (1050, 550 and 225 mm year–1) and in Triticum aestivum L. wheat genotypes differing in drought tolerance. A decrease in the osmotic pressure of the nutrient solution from –0.027 to –1.8 MPa resulted in significant water loss, a low degree of stomatal closure and a decrease in the intercellular CO2 concentration (Ci) in Aegilops genotypes originating from dry habitats, while in wheat genotypes high osmotic stress increased stomatal closure, resulting in a low level of water loss and high Ci. Nevertheless, under saturating light at normal atmospheric CO2 levels, the rate of CO2 assimilation was higher for the Aegilops accessions, under high osmotic stress, than for the wheat genotypes. Moreover, in the wheat genotypes CO2 assimilation exhibited less or no O2 sensitivity. These physiological responses were manifested in changes in the growth rate and biomass production, since Aegilops (Ae550, Ae225) genotypes retained a higher growth rate (especially in the roots), biomass production and yield formation after drought stress than wheat. These results indicate that Aegilops genotypes, originating from a dry habitat have better drought tolerance than wheat, making them good candidates for improving the drought tolerance of wheat through intergeneric crossing.

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Genetic Dissection of Wheat Genotypes Using Morpho-Physiological Traits for Terminal Heat Tolerance

International Journal of Current Microbiology and Applied Sciences ◽

10.20546/ijcmas.2018.702.048 ◽

2018 ◽

Vol 7 (2) ◽

pp. 367-372

Author(s):

Amarjeet Kumar ◽

Swa ti ◽

Anil Kumar ◽

Sneha Adhikari ◽

Birendra Prasad

Keyword(s):

Heat Tolerance ◽

Physiological Traits ◽

Genetic Dissection ◽

Wheat Genotypes

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IDENTIFICATION OF DROUGHT TOLERANT WHEAT GENOTYPES UNDER WATER DEFICIT CONDITIONS

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v4.i2.2016.2830 ◽

2016 ◽

Vol 4 (2) ◽

pp. 206-214 ◽

Cited By ~ 1

Author(s):

Zaid Chachar ◽

N. A. Chachar ◽

Q.I. Chachar ◽

S.M Mujtaba ◽

G.A Chachar ◽

...

Keyword(s):

Water Stress ◽

Seed Germination ◽

Osmotic Stress ◽

Root Length ◽

Dry Weight ◽

Shoot Length ◽

Wheat Genotypes ◽

Maximum Reduction ◽

Drought Tolerant

Climate change is emerging phenomena and causing frequent drought which lead to scaricity of water, which ultimately nagetively affecting wheat (Triticumaestivum L.) yield all around the world. The aim of this study was to explore the potential deought tolerant wheat genotypes for candidate genes exploration. This study was conducted during the year 2014-2015 at Plant Physiology Division, Nuclear Institute of Agriculture (NIA) Tandojam. The six wheat genotypes (cv. MT-1/13, MT-2/13, MT-3/13, MT-4/13 Chakwal-86 and Khirman) were investigated for their response at germination and seedling stage under different water stress treatments (0, -0.5, -0.75 and -1.0 MPa) in controlled conditions. The results of experiments with reference to genotypes revealed that genotype Chakwal-86 shows maximum seed germination (82.58 %), while the genotype Khirman shows maximum shoot length (7.23 cm), root length (15.1 cm), shoot fresh wt. (5.85 g 10-1shoots), root fresh wt. (3.45 g 10-1roots), shoot dry wt. (1.33 g 10-1shoots), root dry wt. (0.69 g 10-1roots). Among the genotypes tested Khirman and MT-4/13 are the tolerant genotypes had the potential to perform better under drought conditions, whereas MT-4/13 and Chakwal-86 were moderate tolerant under water stress conditions. Moreover, the genotypes i.e. MT-1/13 and MT-2/13 are the sensitive genotypes under drought environment. It is concluded from present in-vitro studies that osmotic stress significantly reduced the seed germination shoot/root length fresh and dry weight in all six wheat genotypes. The maximum reduction was found at higher osmotic stress induced by PEG-6000 (-1.0 MPa) significantly.

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Combining Ability for Agromorphological and Physiological Traits in Different Gene Pools of Common Bean Subjected to Water Deficit

Agronomy ◽

10.3390/agronomy9070371 ◽

2019 ◽

Vol 9 (7) ◽

pp. 371 ◽

Cited By ~ 2

Author(s):

Isabella Mendonça Arruda ◽

Vânia Moda-Cirino ◽

Alessandra Koltun ◽

Douglas Mariani Zeffa ◽

Getúlio Takashi Nagashima ◽

...

Keyword(s):

Water Stress ◽

Drought Tolerance ◽

Grain Yield ◽

Common Bean ◽

Water Deficit ◽

Seed Quality ◽

Plant Performance ◽

Physiological Traits ◽

Gene Pools ◽

Group I

Water stress is one of the main limiting factors for common bean crops, negatively affecting grain yield and seed quality. Thus, the objective of this study was to evaluate the inheritance of agromorphological and physiological traits related to drought tolerance in order to identify promising combinations. The experiment was carried out in a greenhouse with a partial diallel scheme between three drought-tolerant genotypes (IAPAR 81, BAT 477. and SEA 5), and nine cultivars widely grown in Brazil (BRS Estilo, IAC Alvorada, IPR Campos Gerais, IPR Uirapuru, IPR Nhambu, BRS Esteio, IPR Garça, BRS Radiante, and DRK 18), in a randomized block design with four replicates. The plants were grown in pots with substrate under 80% of pot capacity until they reached the stage R5, when water supply was restricted to 30% for 20 days in the pots under stress treatment. A wide variability for the agromorphological and physiological traits was observed. Water deficit reduced plant performance for most agromorphological traits and altered their physiological metabolism. Additive and non-additive effects are involved in the genetic control of the majority of agromorphological and physiological traits both under water stress and control (well-watered) conditions. The parental genotypes BAT 477 (group I) and IAC Alvorada, IPR Uirapuru, and BRS Esteio (group II) may be included in breeding programs aiming at improving drought tolerance in common bean since they present high positive general combining abilities for agromorphological traits. The crosses IAPAR 81 × IPR Campos Gerais, and SEA 5 × BRS Radiante resulted in the best combinations considering grain yield per plant and total dry biomass, when cultivated under water deficit.

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