针对坪用质量、抗病虫性以及繁殖性能等性状,对有代表性的60份结缕草(Z oy sia spp.)加以评价。结果表明:不同性状变异系数排序为:繁殖性能(种子产量>生长速度)>抗病虫性(抗锈病>抗螨虫性)>坪用质量(旺盛生长季>缓慢生长...针对坪用质量、抗病虫性以及繁殖性能等性状,对有代表性的60份结缕草(Z oy sia spp.)加以评价。结果表明:不同性状变异系数排序为:繁殖性能(种子产量>生长速度)>抗病虫性(抗锈病>抗螨虫性)>坪用质量(旺盛生长季>缓慢生长季);快速生长季节(5-9月)草坪质量显著受锈病和种子产量的影响,而缓慢生长季节(10-4月)坪用质量受锈病和种子产量的影响不显著;而结缕草种子产量与其生长速度呈显著负相关;Z039、Z091以及Z016等9份种源是种子繁殖型优良选系,而Z097、Z002、Z036等10份种源是营养繁殖型优良选系。展开更多
Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive hig...Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive high-temperature adult-plant resistance gene and confers resistance to a broad spectrum of Pst races.We previously showed that WKS1 phosphorylates the thylakoid ascorbate peroxidase protein and reduces its ability to detoxify peroxides,which may contribute to the accumulation of reactive oxygen species(ROS).WKS1-mediated Pst resistance is accompanied by leaf chlorosis in Pst-infected regions,but the un-derlying mechanisms remain elusive.Here,we show that WKS1 interacts with and phosphorylates PsbO,an extrinsic member of photosystem Ⅱ(PS Ⅱ),to reduce photosynthesis,regulate leaf chlorosis,and confer Pst resistance.A point mutation in PsbO-A1 or reduction in its transcript levels by RNA interference resulted in chlorosis and reduced Pst sporulation.Biochemical analyses revealed that WKS1 phosphorylates PsbO at two conserved amino acids involved in physical interactions with PS Ⅱ and reduces the binding affinity of PsbO with PS Ⅱ.Presumably,phosphorylated PsbO proteins dissociate from the PS Ⅱ complex and then un-dergo rapid degradation by cysteine and aspartic proteases.Taken together,these results demonstrate that perturbations of wheat PsbO by point mutation or phosphorylation by WKS1 reduce the rate of photo-synthesis and delay the growth of Pst pathogen before the induction of ROS.展开更多
The influence of Cr on the initial corrosion behavior of low-alloy steels exposed to a CO2–O2–H2S–SO2 wet–dry corrosion environment was investigated using weight-loss measurements, scanning electron microscopy, N2...The influence of Cr on the initial corrosion behavior of low-alloy steels exposed to a CO2–O2–H2S–SO2 wet–dry corrosion environment was investigated using weight-loss measurements, scanning electron microscopy, N2 adsorption tests, X-ray diffraction analysis, and electrochemical impedance spectroscopy. The results show that the corrosion rate increases with increasing Cr content in samples subjected to corrosion for 21 d. However, the rust grain size decreases, its specific surface area increases, and it becomes more compact and denser with increasing Cr content, which indicates the enhanced protectivity of the rust. The results of charge transfer resistance(Rct) calculations indicate that higher Cr contents can accelerate the corrosion during the first 7 d and promote the formation of the enhanced protective inner rust after 14 d; the formed protective inner rust is responsible for the greater corrosion resistance during long-term exposure.展开更多
文摘针对坪用质量、抗病虫性以及繁殖性能等性状,对有代表性的60份结缕草(Z oy sia spp.)加以评价。结果表明:不同性状变异系数排序为:繁殖性能(种子产量>生长速度)>抗病虫性(抗锈病>抗螨虫性)>坪用质量(旺盛生长季>缓慢生长季);快速生长季节(5-9月)草坪质量显著受锈病和种子产量的影响,而缓慢生长季节(10-4月)坪用质量受锈病和种子产量的影响不显著;而结缕草种子产量与其生长速度呈显著负相关;Z039、Z091以及Z016等9份种源是种子繁殖型优良选系,而Z097、Z002、Z036等10份种源是营养繁殖型优良选系。
基金This research is supported by the National Key R&D Program of China(2016YFD0100500)the National Science Foundation of China(NSFC)(31772146,31972350)for J.G.J.D.acknowledges support from BARD and the Howard Hughes Medical Institute.We thank an open project for support from the National Key Laboratory of Wheat and Maize Crop Science,Henan Agricultural University.
文摘Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive high-temperature adult-plant resistance gene and confers resistance to a broad spectrum of Pst races.We previously showed that WKS1 phosphorylates the thylakoid ascorbate peroxidase protein and reduces its ability to detoxify peroxides,which may contribute to the accumulation of reactive oxygen species(ROS).WKS1-mediated Pst resistance is accompanied by leaf chlorosis in Pst-infected regions,but the un-derlying mechanisms remain elusive.Here,we show that WKS1 interacts with and phosphorylates PsbO,an extrinsic member of photosystem Ⅱ(PS Ⅱ),to reduce photosynthesis,regulate leaf chlorosis,and confer Pst resistance.A point mutation in PsbO-A1 or reduction in its transcript levels by RNA interference resulted in chlorosis and reduced Pst sporulation.Biochemical analyses revealed that WKS1 phosphorylates PsbO at two conserved amino acids involved in physical interactions with PS Ⅱ and reduces the binding affinity of PsbO with PS Ⅱ.Presumably,phosphorylated PsbO proteins dissociate from the PS Ⅱ complex and then un-dergo rapid degradation by cysteine and aspartic proteases.Taken together,these results demonstrate that perturbations of wheat PsbO by point mutation or phosphorylation by WKS1 reduce the rate of photo-synthesis and delay the growth of Pst pathogen before the induction of ROS.
文摘The influence of Cr on the initial corrosion behavior of low-alloy steels exposed to a CO2–O2–H2S–SO2 wet–dry corrosion environment was investigated using weight-loss measurements, scanning electron microscopy, N2 adsorption tests, X-ray diffraction analysis, and electrochemical impedance spectroscopy. The results show that the corrosion rate increases with increasing Cr content in samples subjected to corrosion for 21 d. However, the rust grain size decreases, its specific surface area increases, and it becomes more compact and denser with increasing Cr content, which indicates the enhanced protectivity of the rust. The results of charge transfer resistance(Rct) calculations indicate that higher Cr contents can accelerate the corrosion during the first 7 d and promote the formation of the enhanced protective inner rust after 14 d; the formed protective inner rust is responsible for the greater corrosion resistance during long-term exposure.
