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作 者:王永民[1] 刘国荣[1] 王志明[1] 佟影[2,3] 任万军
机构地区:[1]吉林省林业科学研究院 [2]吉林市林业科学研究所 [3]吉林省敦化市新开岭林场
出 处:《林业科学》1998年第3期74-79,共6页Scientia Silvae Sinicae
摘 要:落叶松褐锈病对林木当年生长无明显影响,但对第二年生长影响显著。连年发病损失量剧增;不同病情指数(X)每公顷材积生长损失量为Y=194/1+e549337-006893X;该病为害指标———病情指数为36。立木林价、防治效果和成本分别为C、Q、E时,防治指标方程为:194C[1/1+e549337-006893X-1/1+e549337-006893(1-Q)X]-E=0;前一年9月份降水量(X3)、当年5月份平均气温(X1)和8月份相对湿度(X2)为测报因子。预测区域平均病情指数Y=5185+32596X1-042105X2+008627X3±69。The larch needle brown rust ( Triphragmiopsis laricinum (Chou)Tai) is a common larch fungal disease in the east of Jilin Province, China. The Larch ( Larix olgensis) stands infected in the first year generaly grow normally, but in the second year they are affected seriously, the growth loss increases greatly in the stand infected lasting 2 years or over 2 years. Regresion equation was developed to predict disease index ( X ) and volume losses of growth/hm 2( Y):Y=1 94/1+e (5 49337-0 06893X) . The injury index was defined as 35. The equation of the economic threshold was developed to describe the relations among standing volume price( C ), the efficiency of control ( Q ) and the cost of control ( E):1 94C[1/1+e 5 49337-0 06893X -1/1+e 5 49337-0 06893(1-Q)X ]-E=0. The equation of forecasting the mean disease index was: Y=5 185+3 2596X 1-0 42105X 2+0 08627X 3±6 9(Y: mean disease index, X 1 :mean temperature in May of the current year, X 2 :mean relative humidity of the current year, X 3 :mean precipitation in September of the last year).
分 类 号:S763.712.2[农业科学—森林保护学]
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