啮齿动物对水稻产量损失的模拟研究

SIMULATED RESEARCH ON THE RICE YIELD DAMAGED BY RODENT

在水稻的不同生长期进行机械损伤,模拟啮齿动物的危害.结果表明:产量损失的程度随破坏性的增加而加剧,速度与破坏程度呈协同趋势.不同的生长期所产生的影响各异.苗期啮齿动物的破坏不影响产量的减少.分蘖期具有轻度影响.孕穗期始表现明显,以后各期逐渐加剧.水稻生长期对损害有不同程度的补偿作用.依据有害动物管理经济学的观点,稻田灭鼠的理论时间定为孕穗期以后.

This research was carried out in Chengdu districts,China,from 1991 to 1992. The information about rodent damage is simulated by means of cutting rice in 180 samples of lm^2 to a 0%,5%,10%,30% 50% degrees at dif- ferent growing stages.The data represented in table 1(?)2;fig.1,2,3 on the damage to rice are calculated by a sta- tistical method of the analysis of variance and other mathematical analysis methods.The results show that the low- er yield the deeper the damage is.The different effect damaged by rodents occured in different rice growing peri- ods.In general,there is no injury in the shoot period but rice output happened to slight decrease at tillering stage. After booting stage,the yield decreases obviously and is least at mature stage.The results show that it has repara- tive function during a early-growing stage.That authors consider the optiamal time putting the rodenticide should be selected after the booting stage and it is not economical before.Using the formla:y=859. 214e^(-0. 768x),it can forecast a change in the yield (y) under different damaging degrees (x,0≤x≤1) .