Search

Legumes play a crucial role in the restoration and utilization of salinized grassland. To explore the physiological response mechanism of Astragalus membranaceus and Medicago sativa seedlings to salt stress, salt stress culture experiments with five NaCl concentration treatments (0 mmol/L, 50 mmol/L, 100 mmol/L, 200 mmol/L, and 300 mmol/L) were conducted on these two legume seedlings. Morphological characteristics, physiological features, biomass, and the protective enzyme system were measured for both seedlings. Correlation analysis, principal component analysis (PCA), and membership function analysis (MFA) were conducted for each index. Structural equation modeling (SEM) was employed to analyze the salt stress pathways of plants. The results indicated that number of primary branches (PBN), ascorbate peroxidase (APX) activity in stems and leaves, catalase (CAT) activity in roots, etc. were identified as the primary indicators for evaluating the salt tolerance of A. membranaceus during its seedling growth period. And CAT and peroxidase (POD) activity in roots, POD and superoxide dismutase (SOD) activity in stems and leaves, etc. were identified as the primary indicators for evaluating the salt tolerance of M. sativa during its growth period. Plant morphological characteristics, physiological indexes, and underground biomass (UGB) were directly affected by salinity, while physiological indexes indirectly affected the degree of leaf succulence (LSD). Regarding the response of the protective enzyme system to salt stress, the activity of POD and APX increased in A. membranaceus, while the activity of CAT increased in M. sativa. Our findings suggest that salt stress directly affects the growth strategies of legumes. Furthermore, the response of the protective enzyme system and potential cell membrane damage to salinity were very different in the two legumes. [ABSTRACT FROM AUTHOR]

Background: Many arid and semi-arid areas endure from extensive salinization of agricultural land. Nevertheless, it must either develop salinity-tolerant varieties or use agronomic treatments to alleviate the symptoms of stress. Although the cultivated potato, Solanum tuberosum L., is relatively salt sensitive, salinity tolerance was demonstrated in several Solanum relatives. Knowledge of genetic variation for salinity tolerance across diverse species is required for breeding of salinity-tolerant cultivars. Higher osmotic pressures associated with salinity impede plant development and cause plant death; yet, the exogenous application of cellularly recognized molecules to withstand such stress might be a key method. Results: In vitro studies were performed to determine how much genetic variability for salinity tolerance exists in S. tuberosum (tbr), a tetraploid species and S. chacoense (chc), a diploid species in which 13 genotypes were evaluated under 100, 200 or 300 mmol L−1 NaCl and the average tested parameters were compared with the control (no stress). A further experiment was conducted to investigate the effect of exogenous application of osmoregulators and antioxidants, namely, glycine betaine (GB), proline (P) and salicylic acid (SA) at 400, 200 and 100 mg L−1, respectively, which applied solely to counteract the harmful effect of stress on potato plants. The results showed that when plants exposed to salinity, root characteristics, plantlet water content % (PWC), chlorophyll and K+ content, and callus formation all substantially reduced; however, Cl− and Na+ levels, as well as catalase and peroxidase activity, were elevated. In general, chc showed more tolerance compared to tbr with genetic diversity within and among species. Under stress, chc clones, 'A-6', 'C-8' and 'D-2' and tbr cultivars, 'Diamond' and 'Russet Burbank' were more tolerant and yielded the greatest salinity tolerance index. Under stress but with applied GB, SA and P, the adverse consequences of stress were relieved. GB was found to be a good treatment for enhancing all the examined traits. Conclusion: The results indicated that there is a significant genetic variation in salt tolerance between (tbr) cultivars and (chc) clones. GB followed by SA and P could completely or partly reverse the adverse impact of salinity stress on potato plants. [ABSTRACT FROM AUTHOR]

Abstract Background Many arid and semi-arid areas endure from extensive salinization of agricultural land. Nevertheless, it must either develop salinity-tolerant varieties or use agronomic treatments to alleviate the symptoms of stress. Although the cultivated potato, Solanum tuberosum L., is relatively salt sensitive, salinity tolerance was demonstrated in several Solanum relatives. Knowledge of genetic variation for salinity tolerance across diverse species is required for breeding of salinity-tolerant cultivars. Higher osmotic pressures associated with salinity impede plant development and cause plant death; yet, the exogenous application of cellularly recognized molecules to withstand such stress might be a key method. Results In vitro studies were performed to determine how much genetic variability for salinity tolerance exists in S. tuberosum (tbr), a tetraploid species and S. chacoense (chc), a diploid species in which 13 genotypes were evaluated under 100, 200 or 300 mmol L−1 NaCl and the average tested parameters were compared with the control (no stress). A further experiment was conducted to investigate the effect of exogenous application of osmoregulators and antioxidants, namely, glycine betaine (GB), proline (P) and salicylic acid (SA) at 400, 200 and 100 mg L−1, respectively, which applied solely to counteract the harmful effect of stress on potato plants. The results showed that when plants exposed to salinity, root characteristics, plantlet water content % (PWC), chlorophyll and K+ content, and callus formation all substantially reduced; however, Cl− and Na+ levels, as well as catalase and peroxidase activity, were elevated. In general, chc showed more tolerance compared to tbr with genetic diversity within and among species. Under stress, chc clones, ‘A-6’, ‘C-8’ and ‘D-2’ and tbr cultivars, ‘Diamond’ and ‘Russet Burbank’ were more tolerant and yielded the greatest salinity tolerance index. Under stress but with applied GB, SA and P, the adverse consequences of stress were relieved. GB was found to be a good treatment for enhancing all the examined traits. Conclusion The results indicated that there is a significant genetic variation in salt tolerance between (tbr) cultivars and (chc) clones. GB followed by SA and P could completely or partly reverse the adverse impact of salinity stress on potato plants. Graphical Abstract

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone 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.)

Epimedium brevicornu Maxim is a traditional Chinese medicinal plant with important value for curing several diseases, including liver cancer. Seed germination, field seedling emergence, and morphological and physiological traits were measured in developing seeds of E. brevicornu, which were collected at 7, 14, 21, 28, and 35 days after flowering. The results showed that with the fruit pericarp changing from lime green to dark red, the seed volume increased. Furthermore, the dry mass of seeds gradually increased from 0.011 g at 7 d to 0.275 g at 35 d, which was a significantly positive correlation with seed vigour (r = 0.980). The soluble protein content initially increased and then decreased to 11.09 mg/g and presented a maximum at 28 d; however, the soluble sugar content gradually declined to a minimum of 30.45 mg/g at 35 d, which was also significantly negatively correlated with seed vigour (r = −0.915). Furthermore, the unsaturated fatty acids (oleic acid and linoleic acid) increase with seed development. Abscisic acid (ABA) reached a maximum value of 18.45 ng/g at 28 d, and gibberellin (GA3), 3-Indoleacetic acid (IAA) and zeatin-riboside (ZR) initially increased and then decreased. These results suggest that the vigour of E. brevicornu seeds is closely associated with their stage of development, with the highest vigour observed at 28~35 d after flowering. [ABSTRACT FROM AUTHOR]

The investigation was conducted during two successive seasons (2019 /2020 and 2020/2021) on two young mango trees cvs. "Sediek" and "Ewais" to determine the impact of foliar spray with different levels of silicone which applied in form of potassium silicate "25% SiO2+10% k2O" (0.0%, 0.1% and 0.2%) and α-tocopherol "vitamin E" (0 ppm, 200 ppm and 400 ppm) alone or combined, to mitigate the harmful effect of low temperature and negative effect of soil salinity on young mango trees. growth characteristics (tree height, leaf area and shoot length) for trees of Sediek and Ewais mango cvs. negatively influenced by abiotic stresses. Meanwhile, foliar application of potassium silicate "P.S." and/or α-tocopherol "α-Toc." alone or in combination significantly improved the morphological and physiological characteristics compared with control. The foliar application of tocopherol alone was more noticeable compared to sprayed with potassium silicate alone particularly at the higher rates as it maintained the growth and plant performance under abiotic stresses. Abiotic stresses, including salinity, cold caused adverse effects on (RWC) and (MSI) of young mango trees under study. On the other hand, foliar application of P.S. and α-Toc. alone or together enhanced significantly these parameters. Negative relationship was detected among free proline content in leaves of young mango trees grown under adverse environmental conditions and foliar application of potassium silicate and α-tocopherol singular or together. [ABSTRACT FROM AUTHOR]

Abstract Background In this study, we aimed to test the hypothesis that magnesium (Mg) remobilization in citrus plants is regulated by Mg supply and contributes to differences in the growth of the parent and branch organs. Citrus seedlings were grown in sand under Mg deficient (0 mmol Mg2+ L−1, -Mg) and Mg sufficient (2 mmol Mg2+ L−1, + Mg) conditions. The effects on biomass, Mg uptake and transport, gas exchange and chlorophyll fluorescence, as well as related morphological and physiological parameters were evaluated in different organs. Results Mg deficiency significantly decreased plant biomass, with a decrease in total plant biomass of 39.6%, and a greater than twofold decrease in the branch organs compared with that of the parent organs. Reduced photosynthesis capacity was caused by a decreased in pigment levels and photosynthetic electron transport chain disruption, thus affecting non-structural carbohydrate accumulation and plant growth. However, the adaptive responses of branch leaves to Mg deficiency were greater than those in parent leaves. Mg deficiency inhibited plant Mg uptake but enhanced Mg remobilization from parent to branch organs, thus changing related growth variables and physiological parameters, including protein synthesis and antioxidant enzyme activity. Moreover, in the principal components analysis, these variations were highly clustered in both the upper and lower parent leaves, but highly separated in branch leaves under the different Mg conditions. Conclusions Mg deficiency inhibits the growth of the parent and branch organs of citrus plants, with high Mg mobility contributing to differences in physiological metabolism. These findings suggest that Mg management should be optimized for sustainable citrus production.

Epimedium brevicornu Maxim is a traditional Chinese medicinal plant with important value for curing several diseases, including liver cancer. Seed germination, field seedling emergence, and morphological and physiological traits were measured in developing seeds of E. brevicornu, which were collected at 7, 14, 21, 28, and 35 days after flowering. The results showed that with the fruit pericarp changing from lime green to dark red, the seed volume increased. Furthermore, the dry mass of seeds gradually increased from 0.011 g at 7 d to 0.275 g at 35 d, which was a significantly positive correlation with seed vigour (r = 0.980). The soluble protein content initially increased and then decreased to 11.09 mg/g and presented a maximum at 28 d; however, the soluble sugar content gradually declined to a minimum of 30.45 mg/g at 35 d, which was also significantly negatively correlated with seed vigour (r = −0.915). Furthermore, the unsaturated fatty acids (oleic acid and linoleic acid) increase with seed development. Abscisic acid (ABA) reached a maximum value of 18.45 ng/g at 28 d, and gibberellin (GA3), 3-Indoleacetic acid (IAA) and zeatin-riboside (ZR) initially increased and then decreased. These results suggest that the vigour of E. brevicornu seeds is closely associated with their stage of development, with the highest vigour observed at 28~35 d after flowering.

Background: In this study, we aimed to test the hypothesis that magnesium (Mg) remobilization in citrus plants is regulated by Mg supply and contributes to differences in the growth of the parent and branch organs. Citrus seedlings were grown in sand under Mg deficient (0 mmol Mg2+ L−1, -Mg) and Mg sufficient (2 mmol Mg2+ L−1, + Mg) conditions. The effects on biomass, Mg uptake and transport, gas exchange and chlorophyll fluorescence, as well as related morphological and physiological parameters were evaluated in different organs. Results: Mg deficiency significantly decreased plant biomass, with a decrease in total plant biomass of 39.6%, and a greater than twofold decrease in the branch organs compared with that of the parent organs. Reduced photosynthesis capacity was caused by a decreased in pigment levels and photosynthetic electron transport chain disruption, thus affecting non-structural carbohydrate accumulation and plant growth. However, the adaptive responses of branch leaves to Mg deficiency were greater than those in parent leaves. Mg deficiency inhibited plant Mg uptake but enhanced Mg remobilization from parent to branch organs, thus changing related growth variables and physiological parameters, including protein synthesis and antioxidant enzyme activity. Moreover, in the principal components analysis, these variations were highly clustered in both the upper and lower parent leaves, but highly separated in branch leaves under the different Mg conditions. Conclusions: Mg deficiency inhibits the growth of the parent and branch organs of citrus plants, with high Mg mobility contributing to differences in physiological metabolism. These findings suggest that Mg management should be optimized for sustainable citrus production. [ABSTRACT FROM AUTHOR]

Legumes play a crucial role in the restoration and utilization of salinized grassland. To explore the physiological response mechanism of Astragalus membranaceus and Medicago sativa seedlings to salt stress, salt stress culture experiments with five NaCl concentration treatments (0 mmol/L, 50 mmol/L, 100 mmol/L, 200 mmol/L, and 300 mmol/L) were conducted on these two legume seedlings. Morphological characteristics, physiological features, biomass, and the protective enzyme system were measured for both seedlings. Correlation analysis, principal component analysis (PCA), and membership function analysis (MFA) were conducted for each index. Structural equation modeling (SEM) was employed to analyze the salt stress pathways of plants. The results indicated that number of primary branches (PBN), ascorbate peroxidase (APX) activity in stems and leaves, catalase (CAT) activity in roots, etc. were identified as the primary indicators for evaluating the salt tolerance of A. membranaceus during its seedling growth period. And CAT and peroxidase (POD) activity in roots, POD and superoxide dismutase (SOD) activity in stems and leaves, etc. were identified as the primary indicators for evaluating the salt tolerance of M. sativa during its growth period. Plant morphological characteristics, physiological indexes, and underground biomass (UGB) were directly affected by salinity, while physiological indexes indirectly affected the degree of leaf succulence (LSD). Regarding the response of the protective enzyme system to salt stress, the activity of POD and APX increased in A. membranaceus , while the activity of CAT increased in M. sativa . Our findings suggest that salt stress directly affects the growth strategies of legumes. Furthermore, the response of the protective enzyme system and potential cell membrane damage to salinity were very different in the two legumes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mi, Ren, Shi, Wang, Wang, Pang, Kang and Wang.)

The experiment was carried out to study the effects of seedling-strengthening agent (SSA) on morphological and physiological characteristics of rice seedlings. Adult seedling rate, seedling height, dry matter weight and protective enzymes activity were studied with Yux-iangyouzhan. The results showed that under mode A (SSA applied at the bottom of the floppy disk) the seedlings showed the difference. While applying 10 g SSA to each dish under mode A, adult seedling rate reached 73.77%, significantly improved by 17.16% than CK; Seedling height was significantly shortened by 43.51%, and dry weight per unite plant height was significantly improved by 50.53%; SOD and POD activity in leaves were higher than other modes, thus increased antioxidant capacity, then strengthened the rice seedlings. [ABSTRACT FROM AUTHOR]

To examine cracking in pomegranate, fruit characteristics (skin thickness, fruit volume, skin-to-seed ratio, calcium and de-polymerized pectin) and skin biomechanical behavior of two known cultivars (Malas-e-Saveh, Yusef-Khani) were investigated. Malas-e-Saveh a sensitive cultivar was compared to Yusef-Khani which known to be very resistant to cracking. Samples of each cultivars were sorted into two categories cracked (code 1) and perfect fruits (code 0). Skin thickness, fruit shape and volume, 100-seeds with aril weight, skin weight, total fruit weight and skin calcium ion and pectin content were recorded for each fruit. Skin elasticity was tested at three different times (30 and 15 days before harvesting and at day of harvesting); failure strain, failure stress and secant modulus were calculated for the samples. Skin thickness was significantly different between the two cultivars, but no relation was observed between skin thickness and fruit cracking. A significant relationship was observed between fruit cracking, fruit volume, fruit shape, seeds weight ratio and skin weight ratio. Failure Strain of Yusef-Khani was significantly higher than Malas-e-Saveh. Secant modulus and toughness was higher in Malas-e-Saveh than Yousef-Khani. A bio-yield point was observed in Malas-e-Saveh as a main difference in biomechanical behavior between resistant and sensitive cultivars. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the isolation and characterization of long tail Thermus bacteriophage which can be found in the Tengchong hot springs in China. The study involves the use of sampling and phage isolation and electron microscopy during the investigation of the bacteriophage. It also concludes that the characteristics of thermophilic phage in China are the similar to Thermus siphoviruses P23-45 and P74-26.

Twenty-four isolates of Verticillium dahliae from various geographic regions and host origins were assigned to vegetative compatibility groups (VCG) based on complementation between nitrate-non-utilizing (nit) mutants. The VCG assignment was associated with clearly distinguishable morphological and physiological characteristics. Most isolates of VCG 2B produced deep black colonies, small conidia (3.62 ± 0.02 μm), and spherical microsclerotia. They exhibited polyphenol oxidase (PPO) activity, high sporulation rate in shake cultures, fluorescence on sanguinarine-amended PDA (snPDA) and excretion of dark pigment on Czapek Dox agar. The isolates assigned to VCG 4B had significantly longer conidia (4.73 ± 0.04 μm), spherical microsclerotia and white, fluffy colonies due to enhanced production of aerial mycelium. They excreted only traces of dark pigment, exhibited PPO activity, did not fluoresce on snPDA and had limited ability to sporulate in shake cultures. Except for lacking PPO activity the only heterokaryon self-incompatible isolate (HSI) was similar to VCG 4B. Ten isolates of Verticillium longisporum from cruciferous hosts did not produce nit mutants. They had clearly longer conidia (7.41 ± 0.05 μm), formed elongate microsclerotia, and only poorly sporulated in shake cultures. They did not excrete dark pigment, lacked PPO, and failed to fluoresce on snPDA. The results indicate a clear morphological and physiological differentiation not only between the two species V. longisporum and V. dahliae but also among the VCGs of V. dahliae. [ABSTRACT FROM AUTHOR]