论文标题:黄瓜白粉病流行主导因素及病害防治的初步研究
Primary Study on Key Factors Influencing the Epidemic of Cucumber Powdery Mildew and Disease Control
论文作者 王爱英
论文导师 曹克强；朱之堉,论文学位 硕士,论文专业 植物病理学
论文单位 河北农业大学,点击次数 415,论文页数 56页File Size2036k
2003-05-01论文网 http://www.lw23.com/lunwen_2889942/ 黄瓜白粉病;病害流行;植物提取物;病害防治;生物测定;抗性机制
Cucumber powdery mildew; Plant extract; Disease epidemics; Disease control; Mechanism of resistance
本研究选择河北农业大学教学试验基地和保定市郊不同地点对生长季节露地黄瓜白粉病的流行规律进行了研究，对环境条件变化作了记载。品种选用长春密刺、津研-2号和津研-4号，发病后对调查株的新增病叶数进行记载，确定了多个病害严重发生日。生长季节每隔4天对黄瓜叶片进行接种，测定了不同时期病害的潜伏期。结合病害严重发生日和潜伏期找出多个病害严重侵染日。归纳这些严重侵染日的气象条件，得出黄瓜白粉病菌严重侵染的环境条件为：在持续1h降雨后的24h内，最低相对湿度不低于47％；温度在18℃～28.5℃之间，其中降雨是黄瓜白粉病流行的主导因素。 在室内外盆栽条件下对烯唑醇：Ts-109植物提取物按不同比例作了生测试验，结果表明，烯唑醇：Ts-109按有效成分比为2：1和3：1复配，并分别稀释600倍和1200倍时，其防效与12.5％烯唑醇WP3000倍达到了同一显著水平。在室外盆栽条件下，两种混配制剂分别把烯唑醇的用量降低到12.5％烯唑醇WP3000倍标准用量的5.6％和5.0％。 田间药效实验表明烯唑醇：Ts-109(3：1)复配液的1200倍和(2：1)的复配液600倍，田间药效与12.5％烯唑醇WP3000倍达到了同一显著水平，与发病对照相比，防效均达73％以上，且具有一定的保产作用。此混合用法可分别把烯唑醇用量降低到12.5％烯唑醇WP3000倍标准用量的10.0％和11.0％。 对黄瓜植株喷施Ts-109的600倍液可以使植株的叶绿素含量提高，从而促进植株生长，使植株健壮，提高了植株的光合作用和抗逆性。 喷施Ts-109的600倍液和12.5％烯唑醇WP3000倍液使接种后的黄瓜苗叶片内多酚氧化酶和过氧化物酶的活性增强，丙二醛含量降低，相对电导率降低。Ts-109对植物生理生化的影响显示出与化学药剂相似的趋势，但在程度上有一定差异。
Four experimental fields were chosen in the trial field of Agricultural University of Hebei and in the suburb of Baoding city. The epidemic of cucumber powdery mildew on three varietious (Changchunmici, Jinyan-2 and Jinyan-4) was studied in field condition. The weather data in field were recorded hourly by hygrothermograph and rain game. From the start of disease in field, the number of newly disease leaves was accounted everyday on investigation plants and the days with large number of disease occurrence were figured out. Inoculations were made every 4 days on healthy leaves far from diseased area, and the latent periods were measure during the whole growing season.The days with heavy infection were detected by mouing the days with large number of disease occurrence one latent period forward. The crucial weather conations for heavy infection of cucumber powdery mildew were summarized as follows: one hour of rainfall in the critical factor, followed by 24 hours with air relative humidity higher than 47%and temperature between 18 and 28.5 .Bioassay on mixtures of different proportions between diniconazole and plant extract Ts-109 was carried out on cucumber seedlings outside and inside greenhouse. Result showed that the proportions of 2: 1 and 3: 1 is better than the other. The mixtures of 2:1(600 dilution) and 3:1(1200 dilution), protective efficacies, which were at the same remarkable, level with the standard chemical 12.5% diniconazole WP (3000 dilution). Two mixtures only contained diniconazole 5.6% and 5.0% compared to original standard chemical use.Both mixtures showed protective efficacies, which is over 73% as good as 12.5% diniconazole WP(3000 dilution) under field conditions. The two mixtures reduced the amount of chemical diniconazole up to 90.0% of the original standard dosage.Physiological studies showed that Ts-109 extract could increase the account of chlorophyll of cucumber seedlings and made plant grow stronger, and more resistant to plant disease.After being fretted by Ts-109 extract and diniconazole, the activities oft some oxidize enzymes, such as SOD, POD and PPO. The MDA contents and relative were also influenced. POD and PPO were strengthened and MDA and relative conductance rate reduced. Ts-109 and diniconazole showed the same trend.
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