梨品种对黑星病的抗病性研究

不同的梨品种对黑星病的抗病性差异很大,西洋梨不感染,日本梨较中国梨抗病。黑星菌以侵染钉直接穿透叶片角质层侵入。幼叶感病,当达到成熟叶龄后,即使人工接种也不发病。免疫或抗病品种均不同程度地抑制其叶片上分生孢子的萌发和附着胞形成。虽然穿透作用仍能发生在免疫品种上,但接种后三天其叶内游离酚含量显著增加,抑制了侵入菌丝在体内的进一步扩展。

STUDIES ON RESISTANCE OF PEAR VARIETIES TO PEAR SCAB (VENTURIA NASHICOLA)

The ability of different pear varieties to resist pear scab varies. European varieties are not damaged while Japanese pears are more resistant than Chinese ones. Younger leaves are more sensitive to the disease, but mature ones are not infected, The germination of the conidia and formation of appresoria on the surface of immune or resistant varietie are inhibited in different degree. Although the penetration through the cuticle takes place on the immune varieties, the hyphae fail to develop further, The contents of free phenols in the young leaves of the immune varieties, which inoculated 3 days-before, are much higher than in the check ones. The change has not been found in susceptible varieties.