[Objective] The paper was to study the disease grading criterion and assess the yield loss caused by maize rough dwarf disease. [Method] The ear lengths and yields of each healthy and infected plant of 5 cultivars wer...[Objective] The paper was to study the disease grading criterion and assess the yield loss caused by maize rough dwarf disease. [Method] The ear lengths and yields of each healthy and infected plant of 5 cultivars were measured during 2009 and 2010. The severity grading criterion was deduced according to the ear length ratios. [Result]When the ratios were 0.92-1.00, 0.67-0.91, 0.41-0.66, 0.10-0.40 and 0, its corresponding disease grading criterions were 0, 1, 3, 5 and 7, respectively. The severity grading criterion was closely correlated to the yield loss. By analyzing the data of disease indexes and yield loss rates of 27 cultivars with DPS （Data Processing System）, the regression equations were established respectively. According to the comparison with each other, the Weibull Model was proved to have the highest fitting degree. Validating with the disease indexes of 27 cultivars in 2010, the equation supported the feasibility of the equation to predict the yield loss caused by maize rough dwarf disease. [Conclusion] The paper provided theoretical basis for further study on maize rough dwarf disease.展开更多
The ultrastructural alteration of maize plants infected with the maize rough dwarf virus (MRDV) was studied with transmission electron microscopy. The results revealed that aggregates of virus particles , with a diame...The ultrastructural alteration of maize plants infected with the maize rough dwarf virus (MRDV) was studied with transmission electron microscopy. The results revealed that aggregates of virus particles , with a diameter of 60nm, were found in the root cell, and always distributed near the vacuole membrane. However, no such particles were checked in leaf cells. Moreover, no virus was observed in choroplasts, mitochondria nuclei, plasmodesmata or intercellular canal of all kinds of infected cells of maize, either. Structures of various organelles changed in the infected leaf and root cells of maize. An inward collapse and localized splitting of the tonoplast were observed, the chloropoast structure was destroyed by MRDV, and the number of destroyed or dysplasia chloroplast in leaf cells with serious symptoms was more than that in leaves without symptoms. The matrix of mitochondria in cells infected by MRDV decreased and some of them expanded and destructed. Nuclei was abnormal and the nuclear membrane was broken. In addition, the infected cells were characterized by a voluminous cytoplasm containing hypertrophied endoplasmic reticulum, with rich ribosome content and lots of starch grain.展开更多
基金Supported by "the Eleventh Five Year" Science and Technology Project of Anhui Province(08010302172)
文摘[Objective] The paper was to study the disease grading criterion and assess the yield loss caused by maize rough dwarf disease. [Method] The ear lengths and yields of each healthy and infected plant of 5 cultivars were measured during 2009 and 2010. The severity grading criterion was deduced according to the ear length ratios. [Result]When the ratios were 0.92-1.00, 0.67-0.91, 0.41-0.66, 0.10-0.40 and 0, its corresponding disease grading criterions were 0, 1, 3, 5 and 7, respectively. The severity grading criterion was closely correlated to the yield loss. By analyzing the data of disease indexes and yield loss rates of 27 cultivars with DPS （Data Processing System）, the regression equations were established respectively. According to the comparison with each other, the Weibull Model was proved to have the highest fitting degree. Validating with the disease indexes of 27 cultivars in 2010, the equation supported the feasibility of the equation to predict the yield loss caused by maize rough dwarf disease. [Conclusion] The paper provided theoretical basis for further study on maize rough dwarf disease.
文摘The ultrastructural alteration of maize plants infected with the maize rough dwarf virus (MRDV) was studied with transmission electron microscopy. The results revealed that aggregates of virus particles , with a diameter of 60nm, were found in the root cell, and always distributed near the vacuole membrane. However, no such particles were checked in leaf cells. Moreover, no virus was observed in choroplasts, mitochondria nuclei, plasmodesmata or intercellular canal of all kinds of infected cells of maize, either. Structures of various organelles changed in the infected leaf and root cells of maize. An inward collapse and localized splitting of the tonoplast were observed, the chloropoast structure was destroyed by MRDV, and the number of destroyed or dysplasia chloroplast in leaf cells with serious symptoms was more than that in leaves without symptoms. The matrix of mitochondria in cells infected by MRDV decreased and some of them expanded and destructed. Nuclei was abnormal and the nuclear membrane was broken. In addition, the infected cells were characterized by a voluminous cytoplasm containing hypertrophied endoplasmic reticulum, with rich ribosome content and lots of starch grain.
