A new model of calculating the economic threshold of plant disease and insect pest
1999
Hua Juling | Li Xiangmin (Jiangxi Provincial Academy of Agricultural Sciences, Nanchang (China). Inst. of Plant Protection) | Guo Yahui
On the basis of economic threshold model the retrieved loss equals control cost and equation that retrieved yield loss rate equals the contrast yield loss rate minus the yield loss rate of control, a new model of calculating the economic threshold of plant disease and insect pest was put forward in this paper. When the relationship between pest number (x) and yield loss [f(x)] was f(x)=ax+b, the traditional economic threshold calculating was x'=(C.F/N.E.P -b) x 1/a, the new model could be expressed by x=(C.F/N.E.P) x 1/a. Analysis and comparison showed that the new model was more rational
Показать больше [+] Меньше [-]