Mitigation of drought stress effects on soybean gas exchanges induced by Azospirillum brasilense and plant regulators

ABSTRACT Drought stress is a limitation for the agricultural production, having as a primary effect the reduction of plant gas exchanges, and the continuity of its incidence results in a lower yield. This study aimed to evaluate the photosynthetic responses and the soybean yield, concerning the seed inoculation and foliar spray with Azospirillum brasilense and plant regulator containing auxin, gibberellin and cytokinin. A randomized complete block design was used under greenhouse conditions, with five treatments: four under drought stress (control, seed inoculation and foliar spray with A. brasilense and plant regulator) and one irrigated treatment. The soil gravimetric moisture, relative water content, CO2 net assimilation rate, apparent quantum efficiency, light compensation point and grain yield were evaluated. The water deficiency reduced the relative water content by 76.96 % and the soybean gas exchanges by 860.43 %, in the drought stress control. However, when using A. brasilense or plant regulator, the reduction of these values was mitigated, with maximum reductions of 52.40 % in the relative water content and 361.99 % in the gas exchanges. Thus, the mitigation of these effects was directly correlated with the grains yielded by plants, where the use of foliar spray with A. brasilense or plant regulator presented averages 19 % higher than the drought stress control. The applications of foliar spray with A. brasilense and plant regulator mitigate the effects of drought stress on the soybean photosynthesis and culminate in lower yield losses.

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Heritability and mode of gene action determination for grain filling rate and relative water content in hexaploid wheat

Genetika ◽

10.2298/gensr1201025g ◽

2012 ◽

Vol 44 (1) ◽

pp. 25-32 ◽

Cited By ~ 3

Author(s):

Ahmad Golparvar

Keyword(s):

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Stress Condition ◽

Gene Action ◽

Grain Filling ◽

Stress Conditions ◽

Filling Rate ◽

Grain Filling Rate ◽

Relative Water

Mode of gene action, heritability and determination of the effective breeding strategy for improvement of physiological and traits specifically in drought stress conditions is very important. Therefore, this study was conducted by using two drought susceptible and tolerant wheat cultivars. Cultivars Sakha8 (tolerant) and Pishtaz (susceptible) as parents along with F1, F2, BC1 and BC2 generations were sown in a randomized complete block design with three replications in drought stress conditions. Results of analysis of variance indicated significant difference between generations as well as degree of dominance revealed over-dominance for the both traits. Fitting simple additive-dominance model designated that this model was not able to account for changes of traits relative water content and mean of grain filling rate. It was revealed that m-d-h-i-j model for relative water content and m-d-h-i model for mean of grain filling rate are the best models. Estimation of heritability and mode of gene action indicated that selection for improvement of traits studied in stress condition and specifically in early generations have medium genetic gain. In conclusion, grain filling rate is better than relative water content as indirect selection criteria to improve plant grain yield in drought stress condition.

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In vitro screening of rice genotypes using polyethylene glycol under drought stress

Progressive Agriculture ◽

10.3329/pa.v27i2.29321 ◽

2016 ◽

Vol 27 (2) ◽

pp. 128-135 ◽

Cited By ~ 1

Author(s):

J Akte ◽

S Yasmin ◽

MJH Bhuiyan ◽

F Khatun ◽

J Roy ◽

...

Keyword(s):

Water Stress ◽

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Dry Weight ◽

Proline Accumulation ◽

Shoot Length ◽

Fresh Weight ◽

Relative Water

Five rice varieties viz. Binadhan-4, Binadhan-5, Binadhan-6, Binadhan-10 and Iratom-24 were evaluated in vitro under different water stress conditions. Several parameters such as germination percentage, shoot length, root length, shoot-root ratio, fresh weight, dry weight, turgid weight, relative water content and proline accumulation were studied. Drought condition was created by MS medium supplemented with five treatments of PEG, with a control such as 0%, 1%, 2%, 3% and 4% of PEG. The highest germination (100%) was found in the variety Binadhan-10 under low water stress conditions induced by 1% PEG. Similarly, the highest percentage of germination was found in all varieties under control condition (0% PEG). The lowest percentage of germination was obtained in the variety Iratom-24. But under severe stress (4% PEG), the highest percentage of germination was found only in the variety Binadhan-10. Moreover, the variety Binadhan-10 was found to be the best at 4% PEG for shoot length, root length, shoot-root ratio, relative water content and also the best at 1% PEG for fresh weight, dry weight, turgid weight. Water stress decreased relative water content and increased proline accumulation in rice. The highest relative water content was recorded in the variety Binadhan-10 and the lowest value recorded in the variety Binadhan-5. The highest proline content was obtained from the binadhan-6 at the highest treatment (4% PEG). Binadhan-10 showed the best performance almost in all the parameters under drought stress because of its own nature of tolerancy.Progressive Agriculture 27 (2): 128-135, 2016

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Aphid fecundity and defenses in wheat exposed to a combination of heat and drought stress

Journal of Experimental Botany ◽

10.1093/jxb/eraa017 ◽

2020 ◽

Vol 71 (9) ◽

pp. 2713-2722 ◽

Cited By ~ 4

Author(s):

Haicui Xie ◽

Jianqin Shi ◽

Fengyu Shi ◽

Haiyun Xu ◽

Kanglai He ◽

...

Keyword(s):

Abscisic Acid ◽

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Nutritional Quality ◽

Defense Responses ◽

Net Reproductive Rate ◽

Aphid Infestation ◽

Grain Aphid ◽

Relative Water

Abstract Plants are routinely subjected simultaneously to different abiotic and biotic stresses, such as heat, drought, and insect infestation. Plant–insect interactions in such complex stress situations are poorly understood. We evaluated the performance of the grain aphid (Sitobion avenae) in wheat (Triticum aestivum L.) exposed to a combination of heat and drought stresses. We also performed assays of the relative water content, nutritional quality, and responses of phytohormone signaling pathways. Lower relative water content and accumulation of soluble sugars and amino acids were observed in plants exposed to combined heat and drought stress. These conditions increased abscisic acid levels in the absence of aphids, as well as leading to higher levels of jasmonate-dependent transcripts. The grain aphid infestation further increased abscisic acid levels and the abundance of jasmonic acid- and salicylic acid-dependent defenses under the combined stress conditions. Aphids reared on plants grown under drought stress alone showed lower net reproductive rates, intrinsic rates of increase, and finite rates of increase compared with aphids reared on plants in the absence of stress. The heat-treated plants also showed a decreased aphid net reproductive rate. These findings demonstrate that exposure to a combination of stresses enhances plant defense responses against aphids as well as altering nutritional quality.

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Evaluation of diverse cowpea [Vigna unguiculata (L.) Walp.] germplasm accessions for drought tolerance

Legume Research - An International Journal ◽

10.18805/lr-428 ◽

2019 ◽

Author(s):

K.D. Nkoana ◽

Abe Shegro Gerrano ◽

E.T. Gwata

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Water Content ◽

Relative Water Content ◽

Evaluation Method ◽

Moisture Stress ◽

Proline Content ◽

Drought Tolerant ◽

Relative Water ◽

Germplasm Accessions

The genetic potential for drought tolerance in cowpea within the small holder sector has not been fully exploited in South Africa. Thus, a drought evaluation experiment was conducted at the ARC-VOP to evaluate 28 cowpea germplasm accessions including two controls viz. IT96D-602 (drought tolerant) and TVU7778 (susceptible to drought) in the drought screening house using plastic box evaluation method in January, 2017. Genotypes raised for three weeks were subjected to 5 weeks of water stress treatment to determine their physiological response through leaf wilting index, relative water content and proline content followed by re-watering to determine genotype (s) with ability to recover from drought stress. Analyses of variance showed highly significant differences in response to moisture stress among the cowpea accessions for the selected physiological traits except for leaf wilting index at week two of drought stress. Stem greenness and recovery appeared to be a reliable indicator of drought tolerant genotypes which was readily observed in Acc1257, Acc1168, Acc2355, IT96D-602 and Acc5352 which also correlated significantly and positively with relative water content and proline content. The genotypes responded differently to drought stress indicating that there is sufficient genetic variability that can be utilized further in breeding for drought stress within the cowpea species.

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Effects of drought stress and rewatering on antioxidant systems and relative water content in different growth stages of maize (Zea maysL.) hybrids

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2014.943198 ◽

2014 ◽

Vol 61 (4) ◽

pp. 493-506 ◽

Cited By ~ 13

Author(s):

Maryam Goodarzian Ghahfarokhi ◽

Syrus Mansurifar ◽

Ruhollah Taghizadeh-Mehrjardi ◽

Mohsen Saeidi ◽

Amir Mohammad Jamshidi ◽

...

Keyword(s):

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Antioxidant Systems ◽

Growth Stages ◽

Relative Water ◽

Effects Of Drought ◽

Different Growth Stages

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Effect of nitrogen application on the phytochemical production in Jatropha curcas L. (Angiosperms: Euphorbiaceae) during drought conditions

Plant Science Today ◽

10.14719/pst.2019.6.2.523 ◽

2019 ◽

Vol 6 (2) ◽

pp. 183-189

Author(s):

Adewole Adebusola ◽

Odjegba Victor ◽

Iwuala Emmanuel ◽

Afroz Alam

Keyword(s):

Drought Stress ◽

Water Content ◽

Jatropha Curcas ◽

Relative Water Content ◽

Protective Mechanism ◽

Stem Cuttings ◽

Jatropha Curcas L ◽

Relative Water ◽

Simulated Drought ◽

And Control

Nitrogen is an important nutrient for the successful metabolism of plants, but its occurrence in soil is always very limited. This nutrient has a significant role to preserve plants during various stress conditions by altering the production rate of phytochemicals as defense weapons. Hence, this study was carried out to analyze the effect of nitrogen supply on the phytochemical composition and relative water content in Jatropha curcas L. under a simulated drought condition. The selected seedlings were grown from stem cuttings and categorized into different treated three groups along with the control. After the completion of the experiment, the growth pattern and phytochemical production were investigated. An increased malondialdehyde activity (MDA) was reported with a reduction in relative water content (RWC) of the leaf and in the biomass of seedlings under drought stress. A significant decrease in the levels of alkaloids, phenol, flavonoids and tannins with an increase in saponins and terpenoids was also observed in only simulated drought stressed plants. While a significant increase in the levels of total alkaloid, tannins, flavonoids and phenols was observed in those plants where exogenous nitrogen was supplied before the start of drought periods, unlike in treated and control plants. Therefore, it was revealed that application of Nitrogen enabled the plants to possess protective mechanism through the production of phytochemicals that facilitate the cell membrane to reduce the detrimental effects caused by drought stress.

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Effects of Foliar Spray on Morpho-Physiological Parameters under High Temperature Stress in Cotton (Gossypium hirsutum L.)

Madras Agricultural Journal ◽

10.29321/maj.000496 ◽

2021 ◽

Vol 108 (june) ◽

pp. 1-4

Author(s):

Devi M ◽

◽

Vincent s ◽

Babu Rajendra Prasad ◽

Anandham R ◽

...

Keyword(s):

High Temperature ◽

Elevated Temperature ◽

Calcium Carbonate ◽

Ambient Temperature ◽

Water Content ◽

Leaf Area ◽

Relative Water Content ◽

Foliar Spray ◽

Canopy Temperature ◽

Relative Water

High temperature is a critical barrier in most cotton growing areas, limiting cotton growth and development. The present study aimed to evaluate the effects of foliar spray on KC 3 cotton variety grown under ambient (32.66°C) and high temperature (37.21°C) stress in open-top chamber (OTC) with a temperature of 5°C from the ambient temperature for 10d from flowering to boll development stage. Foliar spray of kaolin @ 3% and calcium carbonate @ 5% were sprayed separately to the set of pots both in ambient and elevated temperature on 70th day of flowering. Observations on morphological and physiological parameters were recorded on viz., plant height (cm plant-1), leaf area (cm2 plant-1), relative water content (%), canopy temperature (°C), SPAD, chlorophyll fluorescence (Fv/Fm ratio). Kaolin @ 3% foliar spray significantly increased the plant height, leaf area, relative water content, chlorophyll content and reduced the canopy temperature both in high temperature and ambient temperature conditions. Among these treatments, T2 - kaolin 3% (Ambient) followed by T5 - Kaolin 3% (elevated temperature of 5 °C) recorded higher values as compared to calcium carbonate treatment both in ambient temperature and high temperature condition.

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Hasil, Kualitas Fisik Polong dan Biji Beberapa Genotipe Kacang Tanah menurut Ragam Lengas Tanah pada Fase Generatif

Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) ◽

10.24831/jai.v46i1.11402 ◽

2018 ◽

Vol 46 (1) ◽

pp. 71 ◽

Cited By ~ 1

Author(s):

Agustina Asri Rahmianna ◽

Dan Joko Purnomo

Keyword(s):

Drought Stress ◽

Moisture Content ◽

Water Content ◽

Soil Water ◽

Water Availability ◽

Relative Water Content ◽

Pod Yield ◽

Relative Water ◽

Leaf Relative Water Content ◽

Generative Stage

Drought stress during generative stage affected pod yield, yield components, seed and pod qualities of groundnut (Arachis hypogaea L.). The reseach was carried out to assess the effect of drought stress at various soil water availabilities during generative stage on pod yield, pod and seed physical qualities. The experiment was conducted at Muneng Experimental Farm, Probolinggo District during July-October 2012. Five genotypes were arranged in a RCB design, with 3 replicates. The replications were nested into four treatments of soil water availability (0-100, 0-85, 0-70,0-55 days after sowing/DAS). The pods were harvested at 102 days after sowing. The result showed that the shorter the water availability, the lower the leaf relative water content, pod and seed water contents, number of mature pods, seed size, and intact seeds weight. Pod yield reduced when water was available upto 55 DAS only. Turangga variety had the highest pod yield (1.626 ton ha-1) with low pod and seed physical qualities. GH-51 yielded in 1.076 ton ha-1 with superior pod and seed physical qualities. Despite of its lowest pod yield (0.964 ton ha-1), J-11 produced the same pod and seed physical qualities as GH 51 did. ICGV 86590 was superior on its pod yield (1.338 ton ha-1) with low pod and seed physical qualities. Kancil variety did not perform any superiority.<br /><br />Keywords: intact seeds, leaf relative water content, pod moisture content, seed moisture content

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Differential characterization of physiological and biochemical responses during drought stress in finger millet varieties

10.1101/603944 ◽

2019 ◽

Author(s):

Asunta Mukami ◽

Alex Ngetich ◽

Cecilia Mweu ◽

Richard O. Oduor ◽

Mutemi Muthangya ◽

...

Keyword(s):

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Finger Millet ◽

Drought Tolerant ◽

Early Seedling Growth ◽

Relative Water ◽

Early Seedling ◽

Physiological And Biochemical ◽

Selection Of

AbstractDrought is the most perilous abiotic stress that affects finger millet growth and productivity worldwide. For the successful production of finger millet, selection of drought tolerant varieties is necessary and critical stages under drought stress, germination and early seedling growth, ought to be fully understood. This study investigated the physiological and biochemical responses of six finger millet varieties (GBK043137, GBK043128, GBK043124, GBK043122, GBK043094 and GBK043050) under mannitol-induced drought stress. Seeds were germinated on sterile soil and irrigated with various concentrations of mannitol (200, 400 and 600 mM) for two weeks. Comparative analysis in terms of relative water content (RWC), chlorophyll, proline, and malondialdehyde (MDA) contents were measured the physiological and biochemical characteristics of drought stress. The results showed that increased level of drought stress seriously decreased germination and early seedling growth of finger millet varieties. However, root growth was increased. In addition, exposition to drought stress triggered a significant decrease in relative water content and chlorophyll content reduction the biochemical parameters assay showed less reduction of relative water content. Furthermore, oxidative damage indicating parameters such as proline concentration and MDA content increased. Varieties GBK043137 and GBK043094 were less affected by drought as shown by significant change in the physiological parameters. Our findings reveal the difference and linkage between the physiological responses of finger millet to drought and are vital for breeding and selection of drought tolerant varieties of finger millet. Further investigations on genomic and molecular to deeply insight the detail mechanisms of drought tolerance in finger millet need to explored.

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