[Objective] The study aimed at investigating the influence of enhanced UV-B radiation on photosynthesis of grapevine.[Method] The seedlings of Cabernet sauvignon were treated with different intensities of UV-B radiati...[Objective] The study aimed at investigating the influence of enhanced UV-B radiation on photosynthesis of grapevine.[Method] The seedlings of Cabernet sauvignon were treated with different intensities of UV-B radiation under outdoor conditions,and then the contents of photosynthetic pigments and flavonoids in leaves were determined by measuring the absorbance of leaves extracts at 663,645,470 and 300 nm,respectively.[Result] The content of photosynthetic pigments in the leaves of grapevine obviously increased with time under the treatments of different enhanced UV-B radiation.Compared with the control,the chlorophyll a,chlorophyll b,total chlorophyll and carotenoid were obviously increased by 5%,2%,4% and 3% in the enhanced UV-B radiation treatment of 10.8 μW/cm2（T1）,and in the treatment of 25.6 μW/cm2（T2） the corresponding levels were subsequently increased by 11%,9%,10% and 7% with a significant increase in the content of chlorophyll a.On the other hand,the flavonoids content in the leaves of grapevine were obviously increased by 13%,9% in T1 and T2.[Conclusion] The grapevine has strong adaptability to UV-B radiation,and appropriate enhanced UV-B radiation couldn＇t decrease the photosynthesis of grapevine leaves.展开更多
Harpins play a key role in inducing disease resistance in crops,and identifying their core functional regions and establishing a system for their efficient expression would be very valuable.In this study,large amounts...Harpins play a key role in inducing disease resistance in crops,and identifying their core functional regions and establishing a system for their efficient expression would be very valuable.In this study,large amounts of soluble fusion proteins of harpin HrpZ and its subpeptides were obtained via the optimized induction conditions(28C with 0.5 mmol$L1 IPTG for 6 h)in Escherichia coli BL21(DE3).Hypersensitive response(HR)assays demonstrated that the C-terminal 66 aa of HrpZ(HrpZ_C_2_2)elicited a strong HR in tobacco(Nicotiana benthamiana)and grape(Flame Seedless)leaves.Additionally,treatment with HrpZ,and particularly HrpZ_C_2_2,significantly reduced the disease incidence and severity index of field vine leaves and those inoculated with downy mildew.The determination of the physiological parameters indicated that HrpZ,and especially HrpZ_C_2_2,improved the photosynthesis-and chlorophyll fluorescence-related parameters,enhanced the activity of defense-related enzymes,including SOD,POD,CAT and PAL,and increased the H_(2)O_(2)level.Collectively,we efficiently expressed a core peptide of HrpZ and elucidated its strong ability to elicit a HR and resistance to downy mildew.This research provides insight into understanding the structure and function of HrpZ and will advance the application of HrpZ_C_2_2 to increase the resistance of grapevine to downy mildew.展开更多
文摘[Objective] The study aimed at investigating the influence of enhanced UV-B radiation on photosynthesis of grapevine.[Method] The seedlings of Cabernet sauvignon were treated with different intensities of UV-B radiation under outdoor conditions,and then the contents of photosynthetic pigments and flavonoids in leaves were determined by measuring the absorbance of leaves extracts at 663,645,470 and 300 nm,respectively.[Result] The content of photosynthetic pigments in the leaves of grapevine obviously increased with time under the treatments of different enhanced UV-B radiation.Compared with the control,the chlorophyll a,chlorophyll b,total chlorophyll and carotenoid were obviously increased by 5%,2%,4% and 3% in the enhanced UV-B radiation treatment of 10.8 μW/cm2（T1）,and in the treatment of 25.6 μW/cm2（T2） the corresponding levels were subsequently increased by 11%,9%,10% and 7% with a significant increase in the content of chlorophyll a.On the other hand,the flavonoids content in the leaves of grapevine were obviously increased by 13%,9% in T1 and T2.[Conclusion] The grapevine has strong adaptability to UV-B radiation,and appropriate enhanced UV-B radiation couldn＇t decrease the photosynthesis of grapevine leaves.
基金Major Project of Science and Technology of Shandong Province(Grant No.2022CXGC010605)Fruit Industrial Technology System of Shandong Province(Grant No.SDAIT-06-03)+1 种基金Key Research and Development Program of Shandong Province(Grant No.2022LZGCQY019)Agriculture Improved Variety Project of Shandong Province(Grant No.2020 LZGC008).
文摘Harpins play a key role in inducing disease resistance in crops,and identifying their core functional regions and establishing a system for their efficient expression would be very valuable.In this study,large amounts of soluble fusion proteins of harpin HrpZ and its subpeptides were obtained via the optimized induction conditions(28C with 0.5 mmol$L1 IPTG for 6 h)in Escherichia coli BL21(DE3).Hypersensitive response(HR)assays demonstrated that the C-terminal 66 aa of HrpZ(HrpZ_C_2_2)elicited a strong HR in tobacco(Nicotiana benthamiana)and grape(Flame Seedless)leaves.Additionally,treatment with HrpZ,and particularly HrpZ_C_2_2,significantly reduced the disease incidence and severity index of field vine leaves and those inoculated with downy mildew.The determination of the physiological parameters indicated that HrpZ,and especially HrpZ_C_2_2,improved the photosynthesis-and chlorophyll fluorescence-related parameters,enhanced the activity of defense-related enzymes,including SOD,POD,CAT and PAL,and increased the H_(2)O_(2)level.Collectively,we efficiently expressed a core peptide of HrpZ and elucidated its strong ability to elicit a HR and resistance to downy mildew.This research provides insight into understanding the structure and function of HrpZ and will advance the application of HrpZ_C_2_2 to increase the resistance of grapevine to downy mildew.
