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We evaluated the toxicity of chlorantraniliprole against Pieris rapae (L.) (Lepidoptera:Pieridae) on cabbage (Brassicae oleracea variety eapitata L.),and examined the persistence of chlorantraniliprole on field-aged cabbage leaf residues against 5-day-old larvae.Efficacies of chlorantraniliprole and other insecticides to P.rapae (L.) were tested under field conditions for two seasons in Hunan province,south-central China.The LC50 values of chlorantraniliprole by contact for the first to second instar (early) and the third to fourth instar (late) P.rapae were 7.92 and 11.34 mg/l,respectively.The LC50 values of ehlorantraniliprole through ingestion for early and late instar P.rapae were 0.95 and 4.32 mg/l,respectively.The toxicity of chlorantraniliprole on 0 to 28 day-old leaf residues declined gradually under the field conditions.Almost all larvae died on day 5 after being fed with 0 to 21-day-old leaf residues,and the mortalities were as high as 83.3% and 72.5% after being fed with 21-and 25-day-old leaf residues,respectively.With one application,chlorantraniliprole suppressed P.rapae (L.) larvae below the economic threshold for 21-28 days.The results of two field trials showed that chlorantraniliprole applied at 52 mg active ingredient (a.i.)/1 was effective against P.rapae (L.) larvae on cabbage.In addition,we showed that chlorantraniliprole was as effective as indoxacarb and spinosad,and was significantly more effective than emamectin benzoate.These results indicated that it is possible to provide marketable cabbages with three applications of chlorantraniliprole per season.