| In order to provide better technical guidance for factory production and better theoretical foundation for controlling the Alternanthera philoxeroides Griseb by using Agasicles hygrophila Selmamet vogt,effect of temperature stress,humidity stress,photoperiod stress,nutrition stress,herbicide stress and the number of mating on the Agasicles hygrophila Selmamet vogt were tested in the paper.The results showed that:The A.hygrophila hatching eggs was affected under the low temperature stress and high temperature stress,even more significantly under the high temperature stress.The first stage of the A.hygrophila larvae was dead under 4-12 and 35-40℃.High temperature stress had produced a pupation inhibition to the larvae. The A.hygrophila females began to lay eggs under 12℃and inhibited when the temperature rose to 35℃or above.under 25℃,the females lay more eggs than under others temperature, with an average of 7397 eggs. The food ingestion of The A.hygrophila adult increased as the temperature rose from 4 to 25℃,and reached the largest at 25℃,but the adult stopped laying as the temperature rose to 40℃.The maximum life span of adult females and males were at 12℃,and were 53.5d and 44.2d.The temperature too high or too low had led to lower adult life span.Humidity had effect on the A.hygrophila eggs hatch rate, the larvae pupate rate and the adult fecundity,but had not on the A.hygrophila eclosion rate. The A.hygrophila eggs hatch rate and the larvae pupate rate increased as the humidity rose,even the food ingestion and the egg laying amount of the adult increased smartly.The females had more longer life span than the males at different humidity.at 98% RH,the A.hygrophila females and males reached the maximum life span,and were 44.7d and 39.7d;the egg laying amount was as more as 8300,and the food ingestion was 5883.5mg.Under 12L constant photoperiod, the egg hatching rate of the A.hygrophila,as the larvae pupation rate, the females egg laying amount, and the food ingestion and the life span of male and female,reached the maximum value. Photoperiod had little effect on the A.hygrophila eggs hatch rate, too long or too short had led to decrease the larvae pupate rate the A.hygrophila eclosion rate of pupae under the long-photoperiod was higher than short-photoperiod,and the A.hygrophila duration shortened 0.8d. the least egg laying amount was under OL,and the largest,as more as 8472,was under 12L.By using Starane,glyphosate and Penoxsulam, the tiptop security of A.hygrophila was Starane,and the optimum concentration was 0.75L/ha. After 2 days spray, the largest A. philoxeroides ingestion of A.hygrophila adult was sprayed by Starane;the larvae stopped ingestion After 3 days spray by Starane at 4.50L/ha and 6.00L/ha; After 5 days spray, females livability was lower than males livability, the most female fecundity was Starane and the least was glyphosate,the female fecundity was suppressed evidently by glyphosate.Nutrition stress had effect on the food ingestion of the A.hygrophila larvae and the adults, also on the the A.hygrophila females egg laying amount. Mixed leaf feeding, the larvae select high-and low-SPAD value of leaves as a 7.6:1 ratio,but the adults as a 4.0:1 ratio; the females egg laying amount was severely affected by feeding low SPAD value of leaves and food shortage,even did not lay any eggs under only providing 10-50% food;the females starvation endurance ability more stronger than the males,the mortality of A.hygrophila rose sharply as the decrease of food.Unmating females could also lay eggs,but the eggs could not hatch.In the lifetime, A.hygrophila females fecundity and hatching rate of eggs increased with the increasing in the number of mating; The life span of between mating females and unmating females existed a significant difference,the former would longer 17days; the food ingestion of mating females was significantly higher than unmating females,In the lifetime, the food ingestion of unmating females was only 1411mg,but normal mating female could reach 6425.2mg.
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