In order to determine the physiological mechanism of drought resistance of northern wheat in China,six drought resistant wheat and one sensitivity to drought wheat were planted in pots.They were subjected to drought t...In order to determine the physiological mechanism of drought resistance of northern wheat in China,six drought resistant wheat and one sensitivity to drought wheat were planted in pots.They were subjected to drought treatment and normal water when the plants grew to the 3-leaf stage.Samples were collected at 10,20,30,and 40 days after the drought treatment,respectively.The electrical conductivity,photosynthetic parameters,chlorophyll fluorescence parameters,sugar content,proline content,protein content,and active oxygen scavenging enzyme activity of the plants were detected,and the agronomic traits of the wheat varieties were investigated at maturity.The results indicated that the phenotype and yield-related factors of Darkhan 144 changed little under the drought stress.The relative electrical conductivity of Kefeng 6 and Darkhan 166 was lower under the drought stress,and their cell membrane was less damaged.The Darkhan 144 and Darkhan 166 had higher drought resistance coefficients,and were the wheat varieties with stronger drought resistance.However,the physiological mechanisms of drought resistance of these three wheat were different:Darkhan 144 maintained a higher photosynthetic activity under the drought stress;Darkhan 166 maintained a higher protein content,photosynthetic activity and active oxygen scavenging enzyme activity.In addition,other drought-resistant varieties Kefeng 6,Kefeng 10 and Longmai 26 had a higher content of osmoregulatory substances under the drought stress.展开更多
Forestation in the increasingly urbanized area generates a huge demand for ornamental tree stocks, requiring new approach to promote the cultural efficiency of highly valued seedlings. Chitosan oligosaccharide(COS) is...Forestation in the increasingly urbanized area generates a huge demand for ornamental tree stocks, requiring new approach to promote the cultural efficiency of highly valued seedlings. Chitosan oligosaccharide(COS) is one of biodegradable natural plant growth modifier derived from chitin and an abundant water insoluble biopolymer. In this study, Buddhist pine(Podocarpus macrophyllus)(PM) and Northeast yew(Taxus cuspidata)(TC) were cultured with or without COS addition from 1 July to 17 November 2016. Relative to the TC seedlings, the PM seedlings had greater growth of height and biomass which was found to be negatively correlated with the changes of nitrogen(N) and phosphorus(P) concentrations in shoot during the culture. Only those TC seedlings treated without COS addition had higher proportion of decline in the initial N concentration than that in the PM seedlings. Root P concentration declined less in Buddhist pine seedlings than that in Northeast yew seedlings treated with COS. By 17 of November 2016, both N and P seemed to have been diluted in the PM seedlings and exceed the demand in the TC seedlings. In conclusion, COS had the potential to be used for the culture of ornamental tree seedlings to promote nutrient utilization for shoot biomass accumulation, but more specific effect on nutrient allocation and utilization need to be confirmed by more studies.展开更多
基金the National Ministry of Science and Technology Key Project(2018YFE0123300)the National Modern Agricultural Wheat Industry Technology System Keshan Comprehensive Test Station(CARS‒03‒54)the Collaborative Innovation and Extension System of Modern Agricultural Wheat in Heilongjiang Province。
文摘In order to determine the physiological mechanism of drought resistance of northern wheat in China,six drought resistant wheat and one sensitivity to drought wheat were planted in pots.They were subjected to drought treatment and normal water when the plants grew to the 3-leaf stage.Samples were collected at 10,20,30,and 40 days after the drought treatment,respectively.The electrical conductivity,photosynthetic parameters,chlorophyll fluorescence parameters,sugar content,proline content,protein content,and active oxygen scavenging enzyme activity of the plants were detected,and the agronomic traits of the wheat varieties were investigated at maturity.The results indicated that the phenotype and yield-related factors of Darkhan 144 changed little under the drought stress.The relative electrical conductivity of Kefeng 6 and Darkhan 166 was lower under the drought stress,and their cell membrane was less damaged.The Darkhan 144 and Darkhan 166 had higher drought resistance coefficients,and were the wheat varieties with stronger drought resistance.However,the physiological mechanisms of drought resistance of these three wheat were different:Darkhan 144 maintained a higher photosynthetic activity under the drought stress;Darkhan 166 maintained a higher protein content,photosynthetic activity and active oxygen scavenging enzyme activity.In addition,other drought-resistant varieties Kefeng 6,Kefeng 10 and Longmai 26 had a higher content of osmoregulatory substances under the drought stress.
基金supported by the National Natural Science Foundation of China(31600496)The National Key Research and Development Program of China(2016YFC0500307)
文摘Forestation in the increasingly urbanized area generates a huge demand for ornamental tree stocks, requiring new approach to promote the cultural efficiency of highly valued seedlings. Chitosan oligosaccharide(COS) is one of biodegradable natural plant growth modifier derived from chitin and an abundant water insoluble biopolymer. In this study, Buddhist pine(Podocarpus macrophyllus)(PM) and Northeast yew(Taxus cuspidata)(TC) were cultured with or without COS addition from 1 July to 17 November 2016. Relative to the TC seedlings, the PM seedlings had greater growth of height and biomass which was found to be negatively correlated with the changes of nitrogen(N) and phosphorus(P) concentrations in shoot during the culture. Only those TC seedlings treated without COS addition had higher proportion of decline in the initial N concentration than that in the PM seedlings. Root P concentration declined less in Buddhist pine seedlings than that in Northeast yew seedlings treated with COS. By 17 of November 2016, both N and P seemed to have been diluted in the PM seedlings and exceed the demand in the TC seedlings. In conclusion, COS had the potential to be used for the culture of ornamental tree seedlings to promote nutrient utilization for shoot biomass accumulation, but more specific effect on nutrient allocation and utilization need to be confirmed by more studies.