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1983—1985年,通过定株系统观测,对毛白杨幼苗由锈病造成的生长量损失做了数理分析,提出3个数学模型,可试用于计算不同病情(x)对单株胸径增长量(y)的影响,并可做为研究防治苗圃锈病的经济效益和防治指标的参考。用于1年生养干苗的模型为:y_1=0.2998e~(-0.08481x) 用于2年生养干苗的模型为:y_2=0.4208e~(-0.0457x2) 用于3年生养干苗的模型为:y_3=0.7913e~(-1.0282x3)
From 1983 to 1985, the growth of Populus tomentosa seedlings caused by rust was analyzed by the fixed-plant system. Three mathematical models were proposed to calculate the growth of individual DBH (y) ), And can be used as a reference to study the economic benefits of the prevention and treatment of nursery rust and control indicators. The model used for 1-year-old dry saplings was: y_1 = 0.2998e -0.08481x The model used for 2-year-old dry saplings was: y_2 = 0.4208e ~ (-0.0457x2) The model is: y_3 = 0.7913e ~ (-1.0282x3)