To explore the germination mechanism of salt-stressed rice improved by exogenous proline, and provide a theoretical basis to rice direct sowing technology for salinized soil, the effects of soaking with proline on ger...To explore the germination mechanism of salt-stressed rice improved by exogenous proline, and provide a theoretical basis to rice direct sowing technology for salinized soil, the effects of soaking with proline on germination status, amylase activity and isoenzyme were studied in this paper. The results showed that germination status including germination energy（GE）, germination rate（GR）, relative germination energy（RGE） and relative germination rate（RGR） significantly decreased as the same as the activities of alpha-amylase, beta-amylase and the total amylase under salt stress. Soaking with exogenous proline improved the germination status of rice under salt stress. Moreover, GE and RGE of salt-stressed rice were improved with increasing of proline concentration at the range of 5-45 mmol ·L-1. Soaking with 15 mmol ·L-1 and 30 mmol ·L-1 proline significantly improved the amylase activities（e.g. alpha-amylase, beta-amylase and total amylase） of rice under salt stress. Salt stress inhibited the express of beta-amylase isoenzyme temporarily, but had few impacts on alpha-amylase isozyme. Soaking with 30 mmol ·L-1 proline brightened District I and increased the width of ＇i＇ brand in District II of alpha-amylase isoenzyme, but had few impacts on beta-amylase isoenzyme. In a word, soaking with proline could effectively alleviate the inhibitory effects of salt stress on seed germination.展开更多
Background Cotton is extremely affected by severe natural stresses.Drought is one of the most serious abiotic stress that adversely influences cotton growth,productivity,and fiber quality.Previous studies indicate tha...Background Cotton is extremely affected by severe natural stresses.Drought is one of the most serious abiotic stress that adversely influences cotton growth,productivity,and fiber quality.Previous studies indicate that basic leucinezipper(bZIP)transcription factors are involved in the response of plants to various stresses.However,the molecular function and regulatory mechanism of GhVIP1 in response to drought stress are still unknown.Results In this research,GhVIP1 was cloned from a drought-tolerant variety.Expression of GhVIP1 was up-regulated in response to multiple abiotic stresses,especially under drought stress.And GhVIP1 was highly expressed in the root,stem,and 10 days post-anthesis ovule.Inhibiting the expression of GhVIP1 in cotton using the virus-induced gene silencing method resulted in higher electrical conductivity in leaves,but lower water content under drought stress compared with the WT plant.Overexpression of GhVIP1 in Arabidopsis enhanced plant drought tolerance through increasing the seed germination rate and improving the development of root.The exogenous expression of GhVIP1 up-regulated the transcription of genes associated with drought response and proline biosynthesis during drought stress in Arabidopsis.Conclusion In summary,these results indicated that GhVIP1 played a positive role in plants’response to drought stress.The use of GhVIP1 via modern biotechnology might facilitate the improvement of drought tolerance in cotton cultivars.展开更多
In this experiment,the drought-tolerant soybean variety Heinong 44 and the sensitive soybean variety Heinong 65 were used as experimental materials to study the effects of drought stress and re-watering on the osmotic...In this experiment,the drought-tolerant soybean variety Heinong 44 and the sensitive soybean variety Heinong 65 were used as experimental materials to study the effects of drought stress and re-watering on the osmotic adjustment ability and yield of soybean.The results showed that given a normal water supply,the proline and soluble protein contents of Heinong 44 and Heinong65 showed an increasing trend during the growth process,while the soluble sugar content increased and then decreased.The contents of proline,soluble protein and soluble sugar increased significantly with increasing drought stress,and the magnitude of increase of Heinong 44 was higher than that of Heinong 65.The osmotic adjustment ability of the drought-tolerant variety was significantly higher than that of the sensitive variety and showed consistent performance at different stages.After re-watering,the proline and soluble sugar contents of the flowering and pod-setting stages and the soluble protein content of the seedling stage were restored to the control levels.Drought stress resulted in a decrease in the effective pod number,pod number per pod,100-grain weight and yield.Severe drought had the greatest impact by increasing stress and decreasing soybean yields,which were followed by the flowering,bulging and seedling stages.展开更多
Background： Hypoxia tolerance studies in cotton are very rare in Pakistan. Unpredicted and excessive rainfalls result in severe losses to cotton crop in many regions of the country due to lack of hypoxia tolerance in...Background： Hypoxia tolerance studies in cotton are very rare in Pakistan. Unpredicted and excessive rainfalls result in severe losses to cotton crop in many regions of the country due to lack of hypoxia tolerance in current cotton varieties. The genotypes that can tolerate flooding are not reported earlier. The studies were conducted to explore hypoxia tolerance in local germplasm which will help to develop hypoxia tolerant cotton varieties. Method： An experiment with randomized complete different cotton varieties. The genotypes were given conditions. blocks was designed to study the hypoxia tolerance in two treatments i.e., water logged and non-water logged Results： The genotypes showed significant variability for yield, fiber and physiological traits. The hypoxia studies revealed that there is significant reduction for plant height in water sensitive genotype LRA-5166. The genotype MNH-786 showed better yield and MNH-556 showed superior ginning outturn percentage under water logged conditions. Staple length, strength and micronaire values also decreased under hypoxia. Similar pattern of negative effects were observed for Chlorophyll a, b contents and chl a/b ratio. Two hypoxia tolerant cultivars CIM-573 and MNH-564 had significantly higher chlorophyll a （1.664, 1.551） than other cultivars under both normal and waterlogged conditions. There was a significant decrease in total free amino acids in all genotypes/cultivars due to waterlogging. Free amino acid contents were significantly higher in two waterlogging sensitive cultivars, CEDIX and N-KRISHMA, than other cultivars under both non-waterlogged and waterlogged conditions. Waterlogging caused a significant reduction in shoot soluble proteins and increase in shoot proline. The genotype LRA-5166 was the highest in shoot soluble proteins content and showed significant decrease in shoot proline. Conclusions： With respect to yield MNH-786 showed better results and regarding ginning outturn percentage MNH-556 exhibited superior performance. The genotypes CIM-573 and MNH-564 showed higher chlorophyll a values. The above said genotypes may be exploited for further studies related to hypoxia tolerance.展开更多
基金Supported by the Project of Twelfth Five-year Plan for Sci & Tech Research of China in Rural Areas(2011BAD35B02-01)Program of Sci & Tech Research of China(2011BAD16B11)
文摘To explore the germination mechanism of salt-stressed rice improved by exogenous proline, and provide a theoretical basis to rice direct sowing technology for salinized soil, the effects of soaking with proline on germination status, amylase activity and isoenzyme were studied in this paper. The results showed that germination status including germination energy（GE）, germination rate（GR）, relative germination energy（RGE） and relative germination rate（RGR） significantly decreased as the same as the activities of alpha-amylase, beta-amylase and the total amylase under salt stress. Soaking with exogenous proline improved the germination status of rice under salt stress. Moreover, GE and RGE of salt-stressed rice were improved with increasing of proline concentration at the range of 5-45 mmol ·L-1. Soaking with 15 mmol ·L-1 and 30 mmol ·L-1 proline significantly improved the amylase activities（e.g. alpha-amylase, beta-amylase and total amylase） of rice under salt stress. Salt stress inhibited the express of beta-amylase isoenzyme temporarily, but had few impacts on alpha-amylase isozyme. Soaking with 30 mmol ·L-1 proline brightened District I and increased the width of ＇i＇ brand in District II of alpha-amylase isoenzyme, but had few impacts on beta-amylase isoenzyme. In a word, soaking with proline could effectively alleviate the inhibitory effects of salt stress on seed germination.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(32101797)Central Public-interest Scientific Institution Basal Research Fund(No.1610162023020).
文摘Background Cotton is extremely affected by severe natural stresses.Drought is one of the most serious abiotic stress that adversely influences cotton growth,productivity,and fiber quality.Previous studies indicate that basic leucinezipper(bZIP)transcription factors are involved in the response of plants to various stresses.However,the molecular function and regulatory mechanism of GhVIP1 in response to drought stress are still unknown.Results In this research,GhVIP1 was cloned from a drought-tolerant variety.Expression of GhVIP1 was up-regulated in response to multiple abiotic stresses,especially under drought stress.And GhVIP1 was highly expressed in the root,stem,and 10 days post-anthesis ovule.Inhibiting the expression of GhVIP1 in cotton using the virus-induced gene silencing method resulted in higher electrical conductivity in leaves,but lower water content under drought stress compared with the WT plant.Overexpression of GhVIP1 in Arabidopsis enhanced plant drought tolerance through increasing the seed germination rate and improving the development of root.The exogenous expression of GhVIP1 up-regulated the transcription of genes associated with drought response and proline biosynthesis during drought stress in Arabidopsis.Conclusion In summary,these results indicated that GhVIP1 played a positive role in plants’response to drought stress.The use of GhVIP1 via modern biotechnology might facilitate the improvement of drought tolerance in cotton cultivars.
基金Supported by the National Key R&D Program of China(2018YFD1000903)。
文摘In this experiment,the drought-tolerant soybean variety Heinong 44 and the sensitive soybean variety Heinong 65 were used as experimental materials to study the effects of drought stress and re-watering on the osmotic adjustment ability and yield of soybean.The results showed that given a normal water supply,the proline and soluble protein contents of Heinong 44 and Heinong65 showed an increasing trend during the growth process,while the soluble sugar content increased and then decreased.The contents of proline,soluble protein and soluble sugar increased significantly with increasing drought stress,and the magnitude of increase of Heinong 44 was higher than that of Heinong 65.The osmotic adjustment ability of the drought-tolerant variety was significantly higher than that of the sensitive variety and showed consistent performance at different stages.After re-watering,the proline and soluble sugar contents of the flowering and pod-setting stages and the soluble protein content of the seedling stage were restored to the control levels.Drought stress resulted in a decrease in the effective pod number,pod number per pod,100-grain weight and yield.Severe drought had the greatest impact by increasing stress and decreasing soybean yields,which were followed by the flowering,bulging and seedling stages.
文摘Background： Hypoxia tolerance studies in cotton are very rare in Pakistan. Unpredicted and excessive rainfalls result in severe losses to cotton crop in many regions of the country due to lack of hypoxia tolerance in current cotton varieties. The genotypes that can tolerate flooding are not reported earlier. The studies were conducted to explore hypoxia tolerance in local germplasm which will help to develop hypoxia tolerant cotton varieties. Method： An experiment with randomized complete different cotton varieties. The genotypes were given conditions. blocks was designed to study the hypoxia tolerance in two treatments i.e., water logged and non-water logged Results： The genotypes showed significant variability for yield, fiber and physiological traits. The hypoxia studies revealed that there is significant reduction for plant height in water sensitive genotype LRA-5166. The genotype MNH-786 showed better yield and MNH-556 showed superior ginning outturn percentage under water logged conditions. Staple length, strength and micronaire values also decreased under hypoxia. Similar pattern of negative effects were observed for Chlorophyll a, b contents and chl a/b ratio. Two hypoxia tolerant cultivars CIM-573 and MNH-564 had significantly higher chlorophyll a （1.664, 1.551） than other cultivars under both normal and waterlogged conditions. There was a significant decrease in total free amino acids in all genotypes/cultivars due to waterlogging. Free amino acid contents were significantly higher in two waterlogging sensitive cultivars, CEDIX and N-KRISHMA, than other cultivars under both non-waterlogged and waterlogged conditions. Waterlogging caused a significant reduction in shoot soluble proteins and increase in shoot proline. The genotype LRA-5166 was the highest in shoot soluble proteins content and showed significant decrease in shoot proline. Conclusions： With respect to yield MNH-786 showed better results and regarding ginning outturn percentage MNH-556 exhibited superior performance. The genotypes CIM-573 and MNH-564 showed higher chlorophyll a values. The above said genotypes may be exploited for further studies related to hypoxia tolerance.
