Search

The occurrence of early spring and late frost damage brought severe challenges to the production of walnuts in China, seriously affecting their growth, development, yield and revenue. In order to clarify the harmful characteristics and influencing mechanisms of late frost on walnuts in China, the influencing factors of the degree of damage caused by late frost on walnuts, as well as the changes in physiological and biochemical indicators and molecular mechanisms in response to low temperature stress were reviewed. It was found that research on physiological changes focused on the three aspects including cell membrane system (relative conductivity), antioxidant system (malondialdehyde, superoxide dismutase, peroxidase and catalase) and osmoregulation substances (soluble sugars, soluble protein and proline), in addition, the expression levels of genes such as JrPAL, JrJAZ, JrGRAS, JrICE1, JrCBF/JrDREB1, JrCOR, JrWRKY, JrDHN, JrGST, and JrPUB were induced by low temperature stress. And prospects were put for future research directions, which provided scientific basis for further exploring the response mechanism of walnuts to late frost damage and adopting effective production measures. [ABSTRACT FROM AUTHOR]

Variation in fish temperature is determined by changes in the external aquatic environment, and temperature serves as a crucial regulatory factor for the behavior, physiology, and molecular processes of fish. A rapid decline in water temperature can elicit a strong stress response in fish, potentially inhibiting growth and even leading to mortality. Low temperature stress significantly impacts various life processes of organisms, including growth and development, energy metabolism, and reproductive development. In recent years, there has been increasing research on the effects of low-temperature stress on organisms, with a greater focus at the molecular level. Low temperatures induce a decrease in cellular activity and even growth arrest, resulting in apoptosis. Apoptosis is a form of programmed cell death ubiquitous in the biological world, and it plays a vital role in maintaining the normal physiological function of an organism. Once apoptosis occurs, it is irreversible and cannot be stopped. Temperature regulation is crucial for fish, and current knowledge of the role of leptin in fish primarily focuses on the regulation of feeding, lipid energy metabolism, and reproduction, with limited reports on its role in temperature regulation.Leptin, a protein hormone produced by adipocytes, has long been recognized as a product of the obese gene, which regulates organismal metabolism, neuroendocrine function, and other physiological processes. In animals, it exerts diverse physiological functions related to cell growth, proliferation, apoptosis, and metabolism. The homology of the leptin gene in fish is relatively low compared to that in mammals, and multiple leptin proteins encoded by multiple leptin genes can be produced due to genomic duplication events. Regarding the role of leptin in temperature regulation, more research has been conducted on mammals, mainly related to the regulation of energy metabolism and the influence on temperature adaptation evolution. There has been limited research on the regulatory mechanism of leptin in fish during cold stress.Dissostichus mawsoni belongs to the group of Antarctic vertebrates and has lived in the cold and isolated environment of the Southern Ocean at a temperature of –1.9 ℃ for ~30 million years. It has adapted to the extremely low temperatures of the surrounding Antarctic waters and is an excellent material and living fossil for studying temperature adaptation mechanisms in extreme environments. Compared with other fish species at the same depth, it has a large amount of lipid deposition in its subcutaneous and muscle tissues, mainly triglycerides (TGs). Predictions based on 3D structural models suggest that the partial absence of the lepB structure in D. mawsoni leads to only three α-helices, and lepA has four α-helices and a short and twisted E-helix as well as several irregular turns, forming a hollow barrel-like structure, which differs from the protein structure of all other known leptins. Moreover, previous studies have found a close correlation between lepA and temperature evolution, leading to speculation that Antarctic fish lepB may play an essential role in low-temperature adaptation.In this study, a eukaryotic expression vector of the Antarctic toothfish lepb gene was constructed and transfected into ZFL cells to establish a model of overexpression of the D. mawsoni lepb (DMLB) gene in the ZFL cells. After conducting a cell culture temperature experiment, 10 ℃ was selected as the significant difference temperature. Following 2 weeks of cold stimulation, the DMLB experimental group cells remained viable, whereas the control group cells died. The results indicated that the overexpression of the DMLB gene provided strong resistance to low-temperature conditions. By detecting changes in cell proliferation, apoptosis, reactive oxygen species (ROS) level, and ATP content under low-temperature stress, it was discovered that DMLB maintained cell growth and proliferation, reduced ROS production, and inhibited cell apoptosis. DMLB effectively maintained ATP levels in cells under low-temperature stress, which helps maintain the mitochondrial status and reduce the effects of apoptosis and necrosis caused by low-temperature stress, thereby protecting cells from cold stress. Additionally, the results of Oil red O staining and TG detection suggested that the DMLB gene may slow down the depletion of cell lipids under low-temperature stress, perhaps by lowering lipid metabolism to preserve lipids to cope with low-temperature damage. Consequently, the DMLB gene may be functional in the cold resistance of D. mawsoni by protecting cells from damage at low temperatures, but its specific molecular regulatory mechanism needs to be further explored. In this study, 10 ℃ was used as the key temperature, providing a basis for understanding the regulation of energy homeostasis by the lepb gene in D. mawsoni under low-temperature stress. This study explored the role of the lepB gene in the adaptation of D. mawsoni to extremely low-temperature environments and provided fundamental data for further study of the evolution of similar species in the Antarctic region. Furthermore, this study enriched the basic data related to low-temperature tolerance and provided reference materials for further investigation of the low-temperature tolerance mechanism of leptin in Notothenioids, as well as laid a foundation for further study of the mechanism of leptin in temperature regulation.

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to explore the photosynthesis-related cold-resistant genes in Mandragora chinghaiensis grown at high altitude and low temperature. [Method] Taking 0 °C low temperature stress Qinghai eggplant ginseng as the experimental material, the key time points were found through photosynthetic physiological experiments, and then transcriptomics analysis was carried out to screen photosynthetic related cold-resistant genes and perform real-time fluorescence quantitative analysis. [Result] The net photosynthetic rate, stomatal conductance, transpiration rate, maximum fluorescence, maximum photochemical efficiency of photosystem II, photochemical quenching coefficient, and electron transfer rate showed a gradual downward trend, while the intercellular CO2 concentration, initial fluorescence, and non-photochemical quenching coefficient showed an upward trend. Based on the comprehensive analysis of changes in photosynthetic and chlorophyll fluorescence parameters, the key time node was 12 hours. According to the analysis of transcriptome, seven genes were screened. Through qRT-PCR analysis, the expression of CP43 gene was up-regulated first and then down-regulated, showing an overall upward trend; The expression of CAB-8, САВ-11, СР24-10B, CH-02, FD-C2, and PSI-D2 genes was first down-regulated and then up-regulated, showing an overall downward trend. [Conclusion] The results of the study provided some theoretical support for the screening of photosynthesis-related cold resistance genes and the subsequent transgenic verification, the main purpose of screening genes has been achieved. [ABSTRACT FROM AUTHOR]

Aspartic protease (AP) is a pivotal hydrolase enzyme that assumes a critical role in plant growth, development, resilience against both biological and abiotic stressors. Foxtail millet (Setaria itlica) is the model crop for stress resistance study of C4 gramineous plants, but there are few studies on the gene function of AP (SiAPs) in foxtail millet. In order to further explore the functional role of the APs in foxtail millet, the members of the SiAPs were indentified based on whole-genome screening of SiAPs conserved Pfam sequences, and bioinformatics method was used to analyze their physical and chemical properties, subcellular localization, gene structure, conserved domain, phylogenetic development, promoter cis-acting elements and collinearity by bs. Meanwhile, fluorescence quantitative PCR technique was used to study its expression mode under abiotic stress. The results showed that there were 58 AP gene family members in foxtail millet genome. Phylogenetic tree analysis demonstrated that the gene family could be divided into 5 subfamilies, among which Group B encoded atypical AP, while other subfamilies encoded nucellin-like AP. The analysis of gene structure and conserved motifs revealed that members of the same subfamily of APs in foxtail millet were highly conserved. Collinearity analysis showed that there were a large number of homologous gene pairs between SiAPs and rice (Oryza sativa) and maize (Zea mays) AP genes. The study of promoter cis-acting elements indicated that most members of SiAPs contained cis-acting elements related to abiotic stress and biohormone response, such as cis-acting elements in response to drought and low- temperature stress, and salicylic acid response elements. Further quantitative PCR results uncovered that SiAPs were differentially expressed in the root, stem, leaf and panicle of foxtail millet. The expressions of SiAP3, SiAP9 and SiAP48 genes significantly increased under low temperature stress. Under drought stress and SA treatments, the change trend of some gene expression was basically the same. SiAPs play an important role in regulating foxtail millet response to abiotic stress. The results of this study may provide reference for stress resistance analysis of SiAPs. [ABSTRACT FROM AUTHOR]

Environmental conditions regulate the growth and reproduction of fish. The increase in sea temperature during winter may have adverse effects on Takifugu rubripes. To study the mechanism of low-temperature tolerance of T. rubripes, the expression of antifreeze protein (AFP) gene, cold-induced RNA binding protein (CIRP) gene, high mobility group protein box-1 (HMGB1) gene, and Y-box binding protein (YB-1) gene in the liver, spleen, kidney, brain, heart, intestine, muscle, gonad, and skin tissues of T. rubripes obtained from different temperatures (18℃, 13℃, 8℃, and 5℃) was analyzed by quantitative real-time PCR. The results showed that the AFP gene was widely expressed in tissues, with the highest expression in the muscle (P < 0.05). With the decrease in temperature, the expression of the AFP gene in each tissue showed a significant increasing trend, reaching the highest value in the 5℃ group. The expression of the CIRP gene was the highest in the muscle (P < 0.05). With a decrease in temperature, the trend of CIRP gene expression in various tissues was different. The CIRP gene expression levels of liver, kidney, brain, heart, intestine, and skin showed a trend of initial increase, followed by a decrease, and then an increase. The expression levels in the spleen, muscle, and gonads showed an upward trend, reaching the highest value in the 5℃ group. The expression of the HMGB1 gene was the highest in muscle (P < 0.05), followed by that in the brain, liver, heart and skin. As the temperature decreased, the expression of the HMGB1 gene in all tissues except the liver increased first and then decreased, and reached the maximum value in the 8℃ group, which was significantly higher than that of the other groups (P < 0.05). The expression of the YB-1 gene was the highest in the muscle (P < 0.05), with the lowest expression level in other tissues. As the temperature decreased, the expression level of most tissues (brain, heart, intestine, kidney, liver, muscle, and spleen) increased first, then decreased, and then increased, reaching the minimum value in the 8℃ group (P < 0.05). These results show that the expression levels of the four genes are different at different temperature, reflecting the functional specificity of these four genes. Under low-temperature stress, these genes responded positively. Their expression changed to varying degrees, suggesting that the four genes may have potentially important roles in the adaptation of T. rubripes to low temperatures. In addition, by analyzing the law of gene expression, 8℃ may be the key regulatory point for T. rubripes to deal with low-temperature stress. Too low temperature may cause its regulation disorder. The results of this study can provide a relevant basis for studying the regulation mechanism of the low-temperature response of T. rubripes.

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Screening and identification the low-temperature resistant materials and genes can greatly promote the cultivation of the low-temperature resistant varieties of sorghum. 631 sorghum materials，from the whole world，were treated by the method of 8 ，6 ，4 and 2 d stepwise selection. Meanwhile，we discussed the relationship between sorghum grain color and low-temperature resistant property and the infection rate. 7 higher low-temperature resistant materials were obtained，and 1 broom sorghum from China had the higher relative germination rate and relative seedling-emergence rate after 2 d low-temperature treatment for 14 d. Compared with yellow sorghum and red sorghum，white sorghum is easiest to infect bacteria at the seed germination stage. Red sorghum is most difficult to infect bacteria. More low-temperature resistant materials have different grain color. 6 d or lower temperature treatment will have very significant effect on the germination rate and seedling-emergence rate. With the deepening of sorghum grain color，the infection rate is gradually reduced. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study is to explore exogenous S3307 on alleviating low-temperature stress of coix seedlings. The coix cultivar, "No 5 Yiliao", was selected as the plant material, through nutrient solution cultivating in greenhouse, the effect of different S3307 concentrations(1, 3, 5, 7, 9 mg·L~(-1)) on coix seedlings traits and physiological indicators were explored under low-temperature stress. The results showed, under low-temperature 5 mg·L~(-1) S3307 could significantly increase coix seedlings stem diameter and biomass, which stem diameter and above-ground biomass, low-ground biomass separately were enhanced 11.90%, 13.59%, 10.99%. Leaf width and lateral root number separately were enhanced 7.63%, 37.52%. Meanwhile, addition of 5 mg·L~(-1) S3307 could significantly reduce relative conductivity and MDA, separately being reduced 23.33%, 17.42% compared to CKL. S3307 could also significantly increase soluble sugar and proline content, which leaf soluble sugar and proline content separately were enhanced 17.16%, 11.87%, which root soluble sugar and proline content separately were enhanced 20.00%, 33.42%. Additionally, S3307 could alleviate the cells destroy in ultra-structure level by improving cell membrane structure and chloroplast capsule layer structure. 5 mg·L~(-1) S3307 could enhance the low temperature tolerance of coix seedlings by regulating the growth and physiological indexes, and thus alleviate the damage caused by low-temperature to the coix seedlings.

The leaves of four evergreen plants, i.e., Fatsia japonica, Nerium indicum, Mahonia bealei and Acer cinnamomifolium were used as the experimental materials. By measuring the changes of in vitro leaf in soluble sugar, soluble protein, free proline, POD activity, chlorophyll content and relative electrolytic conductivity under aritificial simulated low temperature, combining the measurements of SPAD, leaf surface features and anatomical changes in organizational structure in the process of natural wintering, the cold resistance of four evergreen tree species was evaluated comprehensively. The results showed that in the process of artificial low temperature stress, the chlorophyll content of the leaves of four evergreen species decreased, the content of soluble protein pea-ked at -20 ℃, and the soluble sugar, free proline, POD activity and relative electrolytic conductivity showed an overall upward trend. The semilethal temperatures of four species were -8.0, -13.4, -19.4 and -14.8 ℃, respectively. During the winter, the leaf SPAD of the four species changed markedly, reflecting that the change of relative chlorophyll content was related to the change of temperature. Meanwhile, the leaf thickness, cutin layer thickness, stockade tissue thickness and tightness of four species increased and the plasmolysis occurred thereafter. Also the content of starch grains and calcium oxalate cluster crystal increased. The typical stomatal pits and the intensive non-glandular trichome within the pits of N. indicum and the sclerenchyma of M. Bealei could improve the cold resistance of plants to some extent. In addition, the phenomena like the breakage of wax layer in leaf surface, the fracture of epidermal hair and the deformation of palisade tissue indicated that plants were damaged to a certain extent by low temperature.