泡桐丛枝病诱导抗性的研究Ⅰ．病原物的诱导抗性

Study on Induced Resistance of Paulownia to Witches'BroomⅠ.Resistance Induced by Inoculating the Patkogenic MLO_s

通过对种根采用根接、苗木采用皮接的方法，进行了泡桐丛枝病病原物诱导抗性试验。结果表明，根接后的当年苗木和皮接后第２年的苗木丛枝病发病率明显提高。其中根接当年苗木发病率为４．２８％～１３．０％，皮接第２年苗木发病率为５．３４％～１１．７６％，对照为０．８３％～１．４５％和１．１４％。用经过根接和皮接诱导后的苗木造林，泡桐幼树丛枝病发病率显著降低。经根接处理后，幼树４ａ生丛枝病发病率均为零，皮接１次诱导后４ａ幼树发病率为０～４．１７％，而对照发病率为１９．８％～３１．５％。本项研究结果初步证明，利用嫁接的方法进行病原物诱导，可提高泡桐幼树的抗病力。

As a challenge inoculating ,Paulownia seedlings were induced by inserting scionon stems or splice graft on roots with the diseased stem and root.The results showed thatthe rate of disease of the inoculated seedling increased significantly in the late of the sameyear(root graft,at 4.28～13.0%)or the next year (stem insert scion,5. 34～11. 76%),compared with the ck's(at the rate of 0.83%～1. 45%and 1. 14%).The second or thirdgeneration of inoculated seedlings were planted in the next year. Through four years, therate of disease of the young trees was 0～4.17%,which was much lower than the 19.8%～31.5%of the ck's. The results demonstrated that the induced resistance of Paulownia towitches' broom could be stimulated by graft inoculating with the diseased stem and root.