不同茬地中樟子松幼苗猝倒病发病及危害规律初探

Study on the Occurrence of Damping-off withPinus sylvestnis var. mongolica Litv.Seedlings Grown in Different Stub Fields

在陕西省横山县对不同茬地樟子松苗期猝倒病发病规律进行了研究,表明农耕茬地樟子松幼苗猝倒病始发期较新开垦地早10 d左右,呈穴状或片状猝倒,发病率为10.90%,显著高于新开地的0.355%。育苗时应尽可能选择新开地。

Pinus sylvestnis var.mongolica Litv.seedlings were grown in different farming stub fields.The occurrence of damping-off were examined and studied.The result showed that damping off taking place in stub field was about10 days earlier than in newly-reclaimed farm land and most occurred in a circle or plot pattern,infection rate to be 10.90% which is 0.355% over the infection rate in newly-reclaimed land.Seedling breeding,therefore,is better to be conducted in the newly-reclaimed land.