冬季修剪对油茶抗软腐病能力的影响

Effects of winter pruning on soft rot disease resistant in Camellia oleifera

为降低油茶林软腐病感病率并提高产量,以7年生油茶的4个品种为对象开展冬季修剪,研究冬季修剪对油茶软腐病发生的影响。结果表明:修剪能有效降低油茶软腐病的感病率,修剪后的病情指数为3.75,而未修剪的病情指数高达30.63,是修剪后的8.2倍;4个品种的抗软腐病能力从高到低依次为G、92A、1B、1A,其中品种G修剪后株感病率为0;修剪能降低油茶的感病程度,修剪后的枝和叶的感病率分别比未修剪低18.5个百分点和18.2个百分点;修剪能显著降低因软腐病而引起的落叶,比未修剪的落叶率低18.4个百分点;当油茶叶面的感病程度达1/4以上时,叶片掉落;油茶软腐病主要发生在树冠中下部,修剪能显著降低树冠中下部的感染率。

In order to reduce infection rate of soft rot and to enhance yield, taking four varieties of Camellia oleifera at seven years old as research objects, effects of winter pruning on soft rot disease occurring in C. oleifera were researched. The results show that pruning can effectively reduce the infection rate of soft rot in C. oleifera. The disease index after pruning is 3.75, and that of no pruning CK is up to 30.63, which is 8.2 times compared with treated tree. The order of four varieties＇ soft rot resistance from high to low is G, 92A, 1B, 1A, and the plant infection rate of variety G is zero after pruning. Pruning can decrease the degree of susceptibility of C. oleifera, and branch and leave infection rate after pruning respectively are lower 18.5 and 18.2 percentage points than CK. Pruning can decrease number of fallen leaves caused by soft rot, and the rate of fallen leaves after pruning is lower 18.4 percentage points than CK. The leaf will drop when infection degree is over a quarter of surface. Pruning can significantly decrease infection rate of middle and lower parts of crown, which are the main parts of soft rot occuring.