病区优树对杨树溃疡病抗性的研究

A Study on Measuring the Resistance of the Plus Tree to the Canker of Poplar

1984年从辽宁省溃疡病区选出不感溃疡病的优树11株。为验证选优效果,及早为病区提供抗病新无性系,经三年室内人工伤皮接种测定,用发病率、发病指数、发病速度指数综合考查优树抗病性差异,结果表明,全部优树均较北京杨感病轻,其中辽宁5号、11号为抗病无性系,其余优树为中抗、中感类无性系。

11 plus trees were selected in 1984 from canker disease regions of the natural hybrids of P. simonii × p. italica. In order to test the effects of plus selection and supply new resistant clones to disease regions as soon as possible, the differences of the plus trees' resistance to Dothiore-lla gregaria Sacc. were evacuated according to their pathogenic rate, pathogenic index and pathogenic velocity index in laboratory for three years by inoculating the disease on the artificially wounded bark. The results suggests that all of the plus tree are more resistible to the disease than P. pyr-amidalis × p. cathayana cv. 'Beijingensis', the most resistant clones of which are Liaoning No.5 and Liaoning No. 11.