斑枯病对罗布麻光合生理特征的影响及严重度分级  

Effects of spot blight on photosynthesis of Apocynum venetum and the scale system of the disease severity

作　　者：高鹏[1] 南志标[1] 段廷玉[1] 张峰[1] 刘起棠 孟繁杰 

机构地区：[1]兰州大学草地农业生态系统国家重点实验室,兰州730020 [2]戈宝绿业有限公司,广东深圳518001

出　　处：《植物保护学报》2015年第4期531-537,共7页Journal of Plant Protection

基　　金：新疆维吾尔自治区援疆项目(201191135)

摘　　要：为明确斑枯病对罗布麻光合生理特征的影响,并据此制定其斑枯病严重度分级标准,在田间条件下研究了斑枯病不同严重度罗布麻叶片的光合生理特征。结果表明：健康罗布麻叶片净光合速率为15.65μmol·m-2·s-1、气孔导度为0.283 mol·m-2·s-1、蒸腾速率为7.98 mmol·m-2·s-1、胞间CO2浓度为467μmol/mol,回归方程计算所得健康叶片的净光合速率与实测值接近。随着罗布麻斑枯病严重度增加,叶片净光合速率、气孔导度和蒸腾速率呈显著指数下降趋势,胞间CO2浓度呈上升趋势;严重度指标与净光合速率、气孔导度、蒸腾速率、胞间CO2浓度回归方程的决定系数从大到小依次为相对变色面积〉相对病斑面积〉病斑数,三者与净光合速率的决定系数依次为0.849、0.796和0.537。根据净光合损失率分别为0、0.1%~10%、10.1%~20%、20.1%~50%、50.1%~80%、80.1%~90%和90.1%~100%及其对应的相对病斑面积和相对变色面积,可将斑枯病严重度分为7级。The spot blight caused by Septoria apocyni is an important disease of Apocynum venetum. The disease had caused a large amount of leaf yellowing and leaf-fall,and serious damage to plant phloem. In this research,field and laboratory experiments were conducted to clarify the effects of spot blight on photosynthesis of A. venetum and to establish the disease severity scale system based on the relative index of photosynthesis and lesion area or chlorotic leaf area. The results showed that the net photosynthetic rate,stomatal conductance,transpiration rate and intercellular carbon dioxide concentrations of healthy leaves were 15. 65 μmol·m- 2·s- 1,0. 283 mol·m- 2·s- 1,7. 98 mmol·m- 2·s- 1and 467 μmol / mol,respectively. S. apocyni infection decreased the photosynthesis index but increased intercellular carbon dioxide. The regression equation coefficients of determination with photosynthetic physiological characteristics rank from high to low were relative chlorotic area（ 0. 849）,relative lesion area（ 0. 796）and lesion numbers（ 0. 537）. A seven severity scale system was established based on the relative lesion area or relative chlorotic area when the net photosynthetic loss rate were 0,0. 1%- 10%,10. 1%-20%,20. 1%- 50%,50. 1%- 80%,80. 1%- 90% and 90. 1%- 100%.

关 键 词：罗布麻壳针孢 罗布麻斑枯病 光合生理特征 严重度分级 

分 类 号：S563.7[农业科学—作物学]