苗期棉花抗黄萎病性品种筛选及光合特性的差异研究
毕业论文关键词： 棉花；黄萎病；气孔限制；非气孔限制；光合特性
Screening of cotton Verticillium wilt resistant cultivars and research ofdifference of photosynthetic characteristics in seeding stage
Abstract： Verticillium wilt in cotton caused by Verticillium dahliae is a plant fungal soil-borne disease,which results in serious loss in yield yearly. Owing to lack of upland cotton anti-source of high resistanceand effective chemicals to defend the disease, this study aims to find out the resistance mechanism andfrom which some suggestions can be inferred in the disease protection. In this study, the photosynthesis andchlorophyll fluorescence characteristics of cotton in eight conventional cotton varieties from YangtzeValley were examined. The net photosynthetic rate, stomatal conductance and intercellular CO2concentration of SM-3 were reduced, while limited stomatal value and non limited stomatal value wereincreased. It suggested significant difference among all the indexes except the intercellular CO2concentration and limited stomatal value.As for the ND-601 under the light stress, the net photosyntheticrate and limited stomatal value were increased, stomatal conductance remained the same level, theintercellular CO2 concentration was decreased. There were no significant difference among all the indexesexcept the net photosynthetic rate. Under the severe stress, ND-601 was consistent with the trend of SM-3,which showed the difference is significant, but the decline was less than SM-3 under severe stress.Thestress of Verticillium wilt led the two cultivars Fv/Fm, Fv/F0, Y(II) and qL to decrease, NPQ to increase,but in ND-601 the range of these indexes was less than SM-3. The result indicated that the reason why theVerticillium wilt caused the decrease in the net photosynthetic rate was the result of the limited stomatalvalue and non limited stomatal value.Owing to the Verticillium wilt stress, the PSⅡ reaction center in twocultivars was damaged, but the degree in ND-601 was less than that of SM-3.
Key words: cotton; Verticillium wilt; limited stomatal value; non limited stomatal value; photosyntheticcharacteristics
目录
摘要1
关键词1
Abstract1
Keywords1
引言1
1材料与方法2
1.1供试材料2
1.2试验设计2
1.2.1苗期水培筛选试验2
1.3测定指标与方法3
1.3.1黄萎病病情分级标准及调查方法3
1.3.2光合、荧光测定方法3
1.3.3数据处理4
2结果与分析4
2.1黄萎病的发生情况4
2.2黄萎病胁迫对不同抗性棉花品种光合作用参数的影响4
2.2.1净光合速率（Pn）4
2.2.2气孔导度（C）4
2.2.3胞间CO2浓度（Ci）4
2.2.4气孔限制值（Ls）4
2.3黄萎病胁迫对不同抗性棉花品种荧光动力学参数的影响4
2.3.1光系统Ⅱ的最大光合效率（Fv/Fm）4
2.3.2光系统Ⅱ的潜在活性（Fv/F0）5
2.3.3光系统Ⅱ的实际光合效率（Y(II)）5
2.3.4非光化学淬灭系数（NPQ）5
2.3.5光化学淬灭系数（qL）5
3结论与讨论5
3.1黄萎病胁迫对棉花光合特性的影响5