Studies on Determining Control Action Threshold by Frass drop Amount of Sucra jujuba
- Received Date: 1996-06-02
- Available Online: 2012-03-17
Abstract: From 1992 to 1995,systematic studies had been made on the frass-drop amount and leaf eating amount of Sucra jujuba, the leaf yield of jujube tree,and the influences of different leaf losing levels on fruit output of jujube trees. The mathematic model of frass-drop amount and average temperature,the estimatic survey model of leaf yield of jujube tree,and the dynamic control action threshold model according to frass-drop amount in per time and per area were set up as: F=0.562 9+0.016 2T,(Total leaf yield area)=(total spur of jujube)×(average jujube deciduous spur of per spur)×(average leaves of per jujube deciduous spur)×(average leaf area), Y=(226.194X3-373.754 6)X3-2(0.565 9+0.016 2T)respectively.The results of field examinations showed that the accuracy of all these models was over 90%.