THE STUDY ON GROWING LOSS ASSESSMENT OF YOUNG POPLAR CAUSED BY DOTHIORELLA GREGARIA
- Received Date: 1990-01-24
- Available Online: 2012-12-04
Abstract: According to the investigation of single tree, the study on assessment of growing loss of young poplars caused by Dothiorella gregaria was carried out. The proportion of area (X5) between disease spots and bark of tree under breast diameter was independent variable; the growth data of breast diameter (Y2) in a year were dependent variable. (X6) and (Y2) of the three species were studied by regression analysis.1.P. pyramidalis×559:Y2=-0.15406+118.52194/(102.9113+X52)2.P. canadensis: Y2=-0.4136+278.32113/(133.0115+X52)3.P. simonii×nigra: Y2=-0.08487+110.16972/(131.4548+X52)It is believed that the three holistic models are useful in grading and loss assessment of the disease.