Inhibition of the degradation of chloroplast membranes during senescence in nuclear 'stay green' mutants of soybean

The bean bug, Riptortus pedestris, is a major pest of soybeans. In order to assess the critical stages of soybean damage by R. pedestris, we tested the damage to soybeans at different growth stages (R2, R4, and R6) caused by five densities of R. pedestris (1, 2, 3, 4, and 5) through a field cage experiment. The results show that the R4 stage was the most sensitive stage in terms of suffering R. pedestris injury damage, followed by the R6 stage and then the R2 stage. The number of stay green leaves was 7.04 per plant, the abortive pod rate of the soybeans was 56.36%, and the abortive seed rate of the soybeans was 46.69%. The dry weight of the soybeans was 14.20 g at the R4 stage; these values of R4 were significantly higher than at the R2 and R6 stages. However, the dry weight of soybean seed was 4.27 g and the nutrient transfer rate was 27.01% in the R4 stage; these values were significantly lower than in the R2 and R6 stages. The number of stay green leaves, abortive pod rates, and abortive seed rates were all increased significantly with increasing pest density at each stage of soybean growth. However, the nutrient transfer rate was significantly decreased with the increase in the pest density. Soybean nutrition factors changed after they suffered R. pedestris injury; the lipid content of the soybean seed decreased and the lipid content of the soybean plant increased compared to controls, when tested with a density of five R. pedestris in the R4 stage. These results will be beneficial to the future management of R. pedestris in soybean fields.

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Molecular Dynamics of Chloroplast Membranes Isolated from Wild-Type Barley and a Brassinosteroid-Deficient Mutant Acclimated to Low and High Temperatures

Biomolecules ◽

10.3390/biom11010027 ◽

2020 ◽

Vol 11 (1) ◽

pp. 27

Author(s):

Iwona Sadura ◽

Dariusz Latowski ◽

Jana Oklestkova ◽

Damian Gruszka ◽

Marek Chyc ◽

...

Keyword(s):

Molecular Dynamics ◽

Temperature Stress ◽

High Temperatures ◽

Biological Membrane ◽

Hydrophobic Core ◽

Wild Type ◽

Chloroplast Membranes ◽

Paramagnetic Resonance ◽

Photosynthetic Membranes

Plants have developed various acclimation strategies in order to counteract the negative effects of abiotic stresses (including temperature stress), and biological membranes are important elements in these strategies. Brassinosteroids (BR) are plant steroid hormones that regulate plant growth and development and modulate their reaction against many environmental stresses including temperature stress, but their role in modifying the properties of the biological membrane is poorly known. In this paper, we characterise the molecular dynamics of chloroplast membranes that had been isolated from wild-type and a BR-deficient barley mutant that had been acclimated to low and high temperatures in order to enrich the knowledge about the role of BR as regulators of the dynamics of the photosynthetic membranes. The molecular dynamics of the membranes was investigated using electron paramagnetic resonance (EPR) spectroscopy in both a hydrophilic and hydrophobic area of the membranes. The content of BR was determined, and other important membrane components that affect their molecular dynamics such as chlorophylls, carotenoids and fatty acids in these membranes were also determined. The chloroplast membranes of the BR-mutant had a higher degree of rigidification than the membranes of the wild type. In the hydrophilic area, the most visible differences were observed in plants that had been grown at 20 °C, whereas in the hydrophobic core, they were visible at both 20 and 5 °C. There were no differences in the molecular dynamics of the studied membranes in the chloroplast membranes that had been isolated from plants that had been grown at 27 °C. The role of BR in regulating the molecular dynamics of the photosynthetic membranes will be discussed against the background of an analysis of the photosynthetic pigments and fatty acid composition in the chloroplasts.

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Rising Atmospheric Temperature Impact on Wheat and Thermotolerance Strategies

Plants ◽

10.3390/plants10010043 ◽

2020 ◽

Vol 10 (1) ◽

pp. 43

Author(s):

Adeel Khan ◽

Munir Ahmad ◽

Mukhtar Ahmed ◽

M. Iftikhar Hussain

Keyword(s):

High Temperature ◽

Industrial Revolution ◽

Foliar Application ◽

Pollen Viability ◽

Grain Filling ◽

Crop Productivity ◽

Potassium Nitrate ◽

Agricultural Crop ◽

Stay Green ◽

Seed Formation

Temperature across the globe is increasing continuously at the rate of 0.15–0.17 °C per decade since the industrial revolution. It is influencing agricultural crop productivity. Therefore, thermotolerance strategies are needed to have sustainability in crop yield under higher temperature. However, improving thermotolerance in the crop is a challenging task for crop scientists. Therefore, this review work was conducted with the aim of providing information on the wheat response in three research areas, i.e., physiology, breeding, and advances in genetics, which could assist the researchers in improving thermotolerance. The optimum temperature for wheat growth at the heading, anthesis, and grain filling duration is 16 ± 2.3 °C, 23 ± 1.75 °C, and 26 ± 1.53 °C, respectively. The high temperature adversely influences the crop phenology, growth, and development. The pre-anthesis high temperature retards the pollen viability, seed formation, and embryo development. The post-anthesis high temperature declines the starch granules accumulation, stem reserve carbohydrates, and translocation of photosynthates into grains. A high temperature above 40 °C inhibits the photosynthesis by damaging the photosystem-II, electron transport chain, and photosystem-I. Our review work highlighted that genotypes which can maintain a higher accumulation of proline, glycine betaine, expression of heat shock proteins, stay green and antioxidant enzymes activity viz., catalase, peroxidase, super oxide dismutase, and glutathione reductase can tolerate high temperature efficiently through sustaining cellular physiology. Similarly, the pre-anthesis acclimation with heat treatment, inorganic fertilizer such as nitrogen, potassium nitrate and potassium chloride, mulches with rice husk, early sowing, presoaking of a 6.6 mM solution of thiourea, foliar application of 50 ppm dithiothreitol, 10 mg per kg of silicon at heading and zinc ameliorate the crop against the high temperature. Finally, it has been suggested that modern genomics and omics techniques should be used to develop thermotolerance in wheat.

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Overexpression of RNA ‐binding bacterial chaperones in rice lead to stay‐green phenotype, improved yield and tolerance to salt and drought stresses

Physiologia Plantarum ◽

10.1111/ppl.13369 ◽

2021 ◽

Author(s):

Guddimalli Rajasheker ◽

Somanaboina Anil Kumar ◽

Palle Surender Reddy ◽

Sujatha Edupuganti ◽

Divya Kummari ◽

...

Keyword(s):

Rna Binding ◽

Stay Green ◽

Salt And Drought Stresses

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Degradation of the photosystem II core complex is independent of chlorophyll degradation mediated by Stay-Green Mg2+ dechelatase in Arabidopsis

Plant Science ◽

10.1016/j.plantsci.2021.110902 ◽

2021 ◽

pp. 110902

Author(s):

Ying Chen ◽

Wataru Yamori ◽

Ayumi Tanaka ◽

Ryouichi Tanaka ◽

Hisashi Ito

Keyword(s):

Photosystem Ii ◽

Chlorophyll Degradation ◽

Core Complex ◽

Stay Green

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Genome-wide association study and gene network analyses reveal potential candidate genes for high night temperature tolerance in rice

Scientific Reports ◽

10.1038/s41598-021-85921-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Raju Bheemanahalli ◽

Montana Knight ◽

Cherryl Quinones ◽

Colleen J. Doherty ◽

S. V. Krishna Jagadish

Keyword(s):

Grain Size ◽

Candidate Genes ◽

Gene Network ◽

Genome Wide Association ◽

Potential Candidate ◽

Genetic Loci ◽

Stay Green ◽

Yield And Quality ◽

Genome Wide ◽

Wide Range

AbstractHigh night temperatures (HNT) are shown to significantly reduce rice (Oryza sativa L.) yield and quality. A better understanding of the genetic architecture of HNT tolerance will help rice breeders to develop varieties adapted to future warmer climates. In this study, a diverse indica rice panel displayed a wide range of phenotypic variability in yield and quality traits under control night (24 °C) and higher night (29 °C) temperatures. Genome-wide association analysis revealed 38 genetic loci associated across treatments (18 for control and 20 for HNT). Nineteen loci were detected with the relative changes in the traits between control and HNT. Positive phenotypic correlations and co-located genetic loci with previously cloned grain size genes revealed common genetic regulation between control and HNT, particularly grain size. Network-based predictive models prioritized 20 causal genes at the genetic loci based on known gene/s expression under HNT in rice. Our study provides important insights for future candidate gene validation and molecular marker development to enhance HNT tolerance in rice. Integrated physiological, genomic, and gene network-informed approaches indicate that the candidate genes for stay-green trait may be relevant to minimizing HNT-induced yield and quality losses during grain filling in rice by optimizing source-sink relationships.

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