朱砂叶螨抗氧化乐果品系选育及遗传分析

OMETHOATE-RESISTANT CARMINE SPIDER MITE(TETRANYCHUS CINNABARINUS BOISDUVAL):SELECTION OF R-STRAIN AND GENTIC ANALYSIS

对采自棉田的朱砂叶螨（Ｔｅｔｒａｎｙｃｈａｓｃｉｎｎａｂａｒｉｎｕｓ）种群使用氧化乐果选择压（６６．６７－１３３．３３μｌ／ｌ）１６次筛选后，抗氧化乐果由８．３３倍上升到３６．９３倍。利用此抗性品系（Ｒ）和来自河南省固始县的敏感品系（Ｓ）杂交和回交，研究了朱砂叶螨抗氧化乐果的遗传方式。正交和反交（ＳＲ和ＲＳ）Ｆ＿１代的ＬＣ－Ｐ线介于Ｓ与Ｒ之间偏向Ｒ方，显性系数Ｄ＿（ＳＲ）和Ｄ＿（ＲＳ）分别为０．５６７９和０．５６５９，表明抗性是由不完全显性基因控制。对Ｆ＿１杂合子与亲本的回交（ＳＲ＿♀×Ｓ＿♂）Ｆ＿２代测定表明抗性由单个基因控制。

n omethoate-resistant strain of carmine spider mite(Tetranvchus cinnabarinus Boisdu-val)was obtained by laboratory selection of a colony collected from Henan cotton field after16 selections with omethoate in a concentration ranging from 66.67 to 133.33(μl/L)during16 generations and got a resistance to this insecticide increased from 8. 33 folds(before selec-tion)to about 36.93 folds。This was compared with a susceptible population collected fromGushi county in Henan province to ensure a homogeneous colony for the mode inheritancetests。LC-P lines of the reciprocal crosses(RS,SR)were closed to those of R strain,and thedegree of dominance(D)was estimated to be 0.5679 and 0.5659, respectively,suggestingthat there were no maternal effects and omethoate resistance in this mite was incompletelydominant.The results obtained from the backcross of SR_♀×S_♂ indicated that omethoate re-sistance was inherited as a single gene。