Magnesium Application Promotes Rubisco Activation and Contributes to High-Temperature Stress Alleviation in Wheat During the Grain Filling

Inhibited photosynthesis caused by post-anthesis high-temperature stress (HTS) leads to decreased wheat grain yield. Magnesium (Mg) plays critical roles in photosynthesis; however, its function under HTS during wheat grain filling remains poorly understood. Therefore, in this study, we investigated the effects of Mg on the impact of HTS on photosynthesis during wheat grain filling by conducting pot experiments in controlled-climate chambers. Plants were subjected to a day/night temperature cycle of 32°C/22°C for 5 days during post-anthesis; the control temperature was set at 26°C/16°C. Mg was applied at the booting stage, with untreated plants used as a control. HTS reduced the yield and net photosynthetic rate (Pn) of wheat plants. The maximum carboxylation rate (VCmax), which is limited by Rubisco activity, decreased earlier than the light-saturated potential electron transport rate. This decrease in VCmax was caused by decreased Rubisco activation state under HTS. Mg application reduced yield loss by stabilizing Pn. Rubisco activation was enhanced by increasing Rubisco activase activity following Mg application, thereby stabilizing Pn. We conclude that Mg maintains Rubisco activation, thereby helping to stabilize Pn under HTS.

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Wheat (Triticum aestivum L.) TaHMW1D Transcript Variants Are Highly Expressed in Response to Heat Stress and in Grains Located in Distal Part of the Spike

Plants ◽

10.3390/plants10040687 ◽

2021 ◽

Vol 10 (4) ◽

pp. 687

Author(s):

Chan Seop Ko ◽

Jin-Baek Kim ◽

Min Jeong Hong ◽

Yong Weon Seo

Keyword(s):

Heat Stress ◽

High Temperature ◽

Temperature Stress ◽

Storage Proteins ◽

Seed Storage ◽

Seed Storage Proteins ◽

Grain Filling ◽

High Temperature Stress ◽

Two Dimensional Gel Electrophoresis ◽

Transcript Variants

High-temperature stress during the grain filling stage has a deleterious effect on grain yield and end-use quality. Plants undergo various transcriptional events of protein complexity as defensive responses to various stressors. The “Keumgang” wheat cultivar was subjected to high-temperature stress for 6 and 10 days beginning 9 days after anthesis, then two-dimensional gel electrophoresis (2DE) and peptide analyses were performed. Spots showing decreased contents in stressed plants were shown to have strong similarities with a high-molecular glutenin gene, TraesCS1D02G317301 (TaHMW1D). QRT-PCR results confirmed that TaHMW1D was expressed in its full form and in the form of four different transcript variants. These events always occurred between repetitive regions at specific deletion sites (5′-CAA (Glutamine) GG/TG (Glycine) or (Valine)-3′, 5′-GGG (Glycine) CAA (Glutamine) -3′) in an exonic region. Heat stress led to a significant increase in the expression of the transcript variants. This was most evident in the distal parts of the spike. Considering the importance of high-molecular weight glutenin subunits of seed storage proteins, stressed plants might choose shorter polypeptides while retaining glutenin function, thus maintaining the expression of glutenin motifs and conserved sites.

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Alterations of Endogenous Hormones, Antioxidant Metabolism, and Aquaporin Gene Expression in Relation to γ-Aminobutyric Acid-Regulated Thermotolerance in White Clover

Antioxidants ◽

10.3390/antiox10071099 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1099

Author(s):

Hongyin Qi ◽

Dingfan Kang ◽

Weihang Zeng ◽

Muhammad Jawad Hassan ◽

Yan Peng ◽

...

Keyword(s):

Gene Expression ◽

High Temperature ◽

Temperature Stress ◽

White Clover ◽

High Temperature Stress ◽

Aminobutyric Acid ◽

Endogenous Hormones ◽

Gaba Level ◽

Antioxidant Metabolism ◽

The Impact

Persistent high temperature decreases the yield and quality of crops, including many important herbs. White clover (Trifolium repens) is a perennial herb with high feeding and medicinal value, but is sensitive to temperatures above 30 °C. The present study was conducted to elucidate the impact of changes in endogenous γ-aminobutyric acid (GABA) level by exogenous GABA pretreatment on heat tolerance of white clover, associated with alterations in endogenous hormones, antioxidant metabolism, and aquaporin-related gene expression in root and leaf of white clover plants under high-temperature stress. Our results reveal that improvement in endogenous GABA level in leaf and root by GABA pretreatment could significantly alleviate the damage to white clover during high-temperature stress, as demonstrated by enhancements in cell membrane stability, photosynthetic capacity, and osmotic adjustment ability, as well as lower oxidative damage and chlorophyll loss. The GABA significantly enhanced gene expression and enzyme activities involved in antioxidant defense, including superoxide dismutase, catalase, peroxidase, and key enzymes of the ascorbic acid–glutathione cycle, thus reducing the accumulation of reactive oxygen species and the oxidative injury to membrane lipids and proteins. The GABA also increased endogenous indole-3-acetic acid content in roots and leaves and cytokinin content in leaves, associated with growth maintenance and reduced leaf senescence under heat stress. The GABA significantly upregulated the expression of PIP1-1 and PIP2-7 in leaves and the TIP2-1 expression in leaves and roots under high temperature, and also alleviated the heat-induced inhibition of PIP1-1, PIP2-2, TIP2-2, and NIP1-2 expression in roots, which could help to improve the water transportation and homeostasis from roots to leaves. In addition, the GABA-induced aquaporins expression and decline in endogenous abscisic acid level could improve the heat dissipation capacity through maintaining higher stomatal opening and transpiration in white clovers under high-temperature stress.

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Untangling irrigation effects on maize water and heat stress alleviation using satellite data

10.5194/hess-2020-627 ◽

2021 ◽

Author(s):

Peng Zhu ◽

Jennifer Burney

Keyword(s):

Heat Stress ◽

High Temperature ◽

Surface Temperature ◽

Temperature Stress ◽

Land Surface ◽

Grain Filling ◽

High Temperature Stress ◽

Temperature Stresses ◽

Stress Alleviation ◽

Irrigation Effects

Abstract. Irrigation has important implications for sustaining global food production, enabling crop water demand to be met even under dry conditions. Added water also cools crop plants through transpiration; irrigation might thus play an important role in a warmer climate by simultaneously moderating water and high temperature stresses. Here we use satellite-derived evapotranspiration estimates, land surface temperature (LST) measurements, and crop phenological stage information from Nebraska maize to quantify how irrigation relieves both water and temperature stresses. Our study shows that, unlike air temperature metrics, satellite-derived LST detects significant irrigation-induced cooling effect, especially during the grain filling period (GFP) of crop growth. This cooling is likely to extend the maize growing season, especially for GFP, likely due to the stronger temperature sensitivity of phenological development during this stage. The analysis also suggests that irrigation not only reduces water and temperature stress but also weakens the response of yield to these stresses. Specifically, temperature stress is significantly weakened for reproductive processes in irrigated crops. The attribution analysis further suggests that water and high temperature stress alleviation contributes to 65 % and 35 % of yield benefit, respectively. Our study underlines the relative importance of high temperature stress alleviation in yield improvement and the necessity of simulating crop surface temperature to better quantify heat stress effects in crop yield models. Finally, untangling irrigation effects on both heat and water stress mitigation has important implications for designing agricultural adaptation strategies under climate change.

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Effects of zinc fertilizer and short-term high temperature stress on wheat grain production and wheat flour proteins

Journal of Integrative Agriculture ◽

10.1016/s2095-3119(18)61911-2 ◽

2018 ◽

Vol 17 (9) ◽

pp. 1979-1990 ◽

Cited By ~ 5

Author(s):

Zhi-qiang TAO ◽

De-mei WANG ◽

Xu-hong CHANG ◽

Yan-jie WANG ◽

Yu-shuang YANG ◽

...

Keyword(s):

High Temperature ◽

Temperature Stress ◽

Wheat Flour ◽

High Temperature Stress ◽

Grain Production ◽

Wheat Grain ◽

Short Term ◽

Zinc Fertilizer

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Dampak Suhu Tinggi terhadap Pertumbuhan dan Hasil Tanaman Padi

Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) ◽

10.24831/jai.v47i3.24892 ◽

2020 ◽

Vol 47 (3) ◽

pp. 248-254

Author(s):

Usamah Jaisyurahman ◽

Desta Wirnas ◽

Trikoesoemaningtyas ◽

Dan Heni Purnamawati

Keyword(s):

High Temperature ◽

Temperature Stress ◽

Growth And Development ◽

Rice Variety ◽

Grain Filling ◽

High Temperature Stress ◽

High Temperature Treatment ◽

Tolerance Index ◽

Grain Number ◽

Grain Number Per Panicle

Global warming becomes a pressure in food production sustainability because it affected crop growth and development. The purpose of this study was to obtain information on the effect of high-temperature stress on the growth and development phase of rice and to evaluate the genotype for tolerance to high-temperature stress. Two environment conditions were used in the field and greenhouse of IPB Cikabayan experimental field, IPB University from August 2016 until February 2017. The study used varieties of IPB 4S, IPB 6R, Mekongga, and Situ Patenggang. High-temperature treatment was done by transferring the rice plants to the greenhouse at 50 days after transplanting. Observations were made on the generative phase in two different environmental conditions. The results showed that the total tillers number, filled grain number per panicle, unfilled grain number per panicle, total grain number per panicle, grain filling rate, percentage of filled grain and filled grain weight per plant had different responses among rice genotypes due to high-temperature stress. High-temperature decreased pollen fertility in all genotypes, which classified IPB 4S as a sensitive genotype and Mekongga as a tolerant genotype. This information could be useful for development and improving rice variety to anticipate high-temperature stress. Keywords: Climate change, fertility, pollen, stress tolerance index

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High-Temperature and Drought Stress Effects on Growth, Yield and Nutritional Quality with Transpiration Response to Vapor Pressure Deficit in Lentil

Plants ◽

10.3390/plants11010095 ◽

2021 ◽

Vol 11 (1) ◽

pp. 95

Author(s):

Noureddine El Haddad ◽

Hasnae Choukri ◽

Michel Edmond Ghanem ◽

Abdelaziz Smouni ◽

Rachid Mentag ◽

...

Keyword(s):

High Temperature ◽

Drought Stress ◽

Vapor Pressure ◽

Grain Yield ◽

Protein Content ◽

Temperature Stress ◽

Nutritional Quality ◽

Vapor Pressure Deficit ◽

High Temperature Stress ◽

The Impact

High temperature and water deficit are among the major limitations reducing lentil (Lens culinaris Medik.) yield in many growing regions. In addition, increasing atmospheric vapor pressure deficit (VPD) due to global warming causes a severe challenge by influencing the water balance of the plants, thus also affecting growth and yield. In the present study, we evaluated 20 lentil genotypes under field conditions and controlled environments with the following objectives: (i) to investigate the impact of temperature stress and combined temperature-drought stress on traits related to phenology, grain yield, nutritional quality, and canopy temperature under field conditions, and (ii) to examine the genotypic variability for limited transpiration (TRlim) trait in response to increased VPD under controlled conditions. The field experiment results revealed that high-temperature stress significantly affected all parameters compared to normal conditions. The protein content ranged from 23.4 to 31.9%, while the range of grain zinc and iron content varied from 33.1 to 64.4 and 62.3 to 99.3 mg kg−1, respectively, under normal conditions. The grain protein content, zinc and iron decreased significantly by 15, 14 and 15% under high-temperature stress, respectively. However, the impact was more severe under combined temperature-drought stress with a reduction of 53% in protein content, 18% in zinc and 20% in iron. Grain yield declined significantly by 43% in temperature stress and by 49% in the combined temperature-drought stress. The results from the controlled conditions showed a wide variation in TR among studied lentil genotypes. Nine genotypes displayed TRlim at 2.76 to 3.51 kPa, with the genotypes ILL 7833 and ILL 7835 exhibiting the lowest breakpoint. Genotypes with low breakpoints had the ability to conserve water, allowing it to be used at later stages for increased yield. Our results identified promising genotypes including ILL 7835, ILL 7814 and ILL 4605 (Bakria) that could be of great interest in breeding for high yields, protein and micronutrient contents under high-temperature and drought stress. In addition, it was found that the TRlim trait has the potential to select for increased lentil yields under field water-deficit environments.

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