西瓜枯萎病抗性机制的研究

THE MECHANISM OF RESISTANCE TO FUSARIUM WILT OF WATERMELON

西瓜幼苗主根中导管的分布,中央导管数目及其木质纤维壁的加厚程度,与西瓜对枯萎病的抗性密切相关。植物体内多酚氧化酶、过氧化物酶活性与西瓜枯萎病的抗性之间不存在显著相关,而抗坏血酸氧化酶活性与枯萎病抗性之间存在着极显著相关。这可作为鉴定和筛选抗病性个体的生化指标。研究还发现抗病品种与感病品种在某些特定氨基酸的含量上有较明显的差别。

The results showed that the distribution of vessels and number of central vessels of root system and the thickness of their cell wall xylem are related to the ability of resistance to Fusarium wilt of watermelon varieties. There was no significant correlation between the activity of poly phenol oxidase and pero-xidase and the resistance, but there was a remarkable correlation between activity of vitamin C oxidase and the resistance. Thus for the activity of vitamin C oxidase can be used as a biochemical parameter for screening watermelon varieties with resistance to Fusarium wilt. The Fusarium wilt disease resistant watermelon varieties have the higher contents of glycine, serine, alanine, threonine, proline and arginie and the Fusarium wilt disease susceptible watr-melon varieties have the higher contents of leucine, methionine and tyrosine.