病害对3个砂梨品种早期落叶的影响

由于一些侵染性病害的影响,浙江省主要梨产区出现早期落叶严重的现象,严重影响了砂梨产业的发展。通过对浙江省杭州市商业梨园主栽品种的田间调查发现,不同品种对病菌的抵抗能力不同。圆黄为黑斑病的易感品种,但对炭疽病的抗性较强;黄花和翠冠较抗黑斑病,但黄花炭疽病的发病率较高;3个品种的锈病发病率没有显著差异。病菌侵染和落叶时间的相关性分析表明,病菌侵染后翠冠和圆黄落叶较黄花早;受黑斑病菌侵染的叶片最易脱落,而梨炭疽病菌和梨锈病菌不易引起落叶,仅在后期形成穿孔。总体上圆黄早期落叶现象最为严重。受梨黑斑病菌侵染后,叶片诱导POD活性的增加来抵御病原菌的侵染。

Influence of Pathogen Infection on Early Leaf Abscission of Three Chinese Pear Cultivars (Pyrus pyrifolia Nakai)

Early leaf abscission caused by pathogen infections is becoming a serious problem in main pear production regions of Zhejiang province and has adversely influenced the development of the pear industry.Field survey on main cultivated pear cultivars was conducted in a commercial orchard in Hangzhou city.The results showed that the disease resistance varied between different cultivars.’Yuanhuang’ was susceptible to black spot disease but resistant to anthracnose;’Huanghua’ and ’Cuiguan’ were more resistant to black spot disease,but ’Huanghua’ was susceptible to anthracnose.There was no significant difference among the three cultivars in the resistance to rust disease.Correlation analysis between pathogen infection and leaf abscission time showed that the leaves of ’Cuiguan’ and ’Yuanhuang’ abscised earlier.Black spot disease was easier to cause leaf abscission than were anthracnose and rust disease,and infection with both diseases caused leaf perforations in the later stages of infection.In general,early leaf abscission of ’Yuanhuang’ pear was more severe.It was also found that POD activities in leaves infected by black spot disease were increased,which led to increased resistance of the infected plants to the disease.