人工接种后次代抗松材线虫松树的抗病性

为了解抗病松树后代对松树线虫的抗性，采用人工接种松树线虫，相隔一定时间调查其枯死情况，用3％酸性染料染色研究了抗性松与普通松水分输导情况，线虫的数量，结果表明，普通黑松3个月后枯死率为91．1％，次代抗性赤松枯死率为4．46％，除中央髓部的水分输导受影响外周边木质部和形成层未受影响；次代抗性黑松除两株水分严重受阻外，其他与赤松相似，接种线虫1周后从次代抗性松树上分离线虫最多，以后逐渐下降，5周后则很少。

Studies on the Resistance of the Second Generation Resistance Pine to Pine Wood Nematode

The death rate of susceptible Japanese black pine was 91.1% after 3 months inoculated with Bursaphelenchus xylophilus.The death rate of second generation resistance Japanese red pine inoculated with different concentration was only 4.46%,no death for second generation resistance Japanese black pine. The results showed that resistance pine had high resistance to pine wood nematode,and resistance had no positive relevance with the inoculation number of pine wood nematode.The occurrence of cavitation had been seen in the pulp of the second generation resistance Japanese red pine inoculated,the cambia and the outer xylem had unaffected.The second generation resistance Japanese black pine had similarity with the second generation resistance Japanese red pine except that 2 tested pines had serious cavitation.There was the greatest number of pine wood nematode isolated from the second generation resistance pine after 1 week and the pine wood nematode could be isolated in the middle of pine stem.