| The red palm weevil, Rhynchophorus ferrugineus (Olivier) was first discovered in 1891 in India. It is becoming an international insect pest. The basic biology and ecology-the behavior of artificial rearing, effects of temperatures on the population growth and effects of artificial diets on development of R. ferrugineus were studied. The main findings were as follows:(1) The mating and oviposition behavior of R. ferrugineus was observed in laboratory. Mating behavior was examined in the whole day, but a peak period of mating occurred in the half hour of the beginning of dark period. Moreover, mating duration and probability were not influenced by body size. Without external interference, mating duration may be more than 1 minute. After the copulation, females bored a hole, and laid an egg each hole. In addition, larval and pupal behaviors were also studied, such as feeding, fighting, exuviating and cocooning. With the development from the young to old larvae, the feeding and drilling were from centre to periphery of palms. Through the behavior of red palm weevil in shaking of cocoon and combination with the observation of the color and texture of the cocoon, the three stages of cocoon could be distinguished.(2) The effect of temperature on the developmental time, survival, and reproduction of R. ferrugineus (Olivier) reared on sugarcane was studied at seven constant temperatures (16, 20,24,28,32,36 and 40℃). The developmental threshold temperatures and effective accumulated temperatures for the whole generation were 17.41℃and 1590.72 DD (degree days), respectively. One generation had the highest survival rate (26.67%) at 28℃. The egg failed to survive at 16℃and 40℃. The number of eggs laid per female (239.47) was the highest at 28℃. The population trend index (I=38.22) and net reproductive rate (Ro=38.3) were the highest at 28℃. The net reproductive rate (Ro=3.36), intrinsic rate of increase (rm= 0.0028) and finite capacity of increase (λ=1.0028) were the lowest at 20℃. The mean generation time (To=85.82) was the shortest at 36℃. The population double time (PDT= 27.08) was the shortest at 32℃. Based on these studies, we concluded that the temperatures from 28℃to 32℃were the most suitable temperatures for the development of R. ferrugineus. (3) The effect of artificial diets on developments of R. ferrugineus reared on palm stems, sugarcanes and semiartificial diets included the main ingredients of palm stems were studied. The cocoon assisted by coconut husk was reported in this paper. The developmental time from larva to adult on Oreodoxa regia, Archontophoehix Alexandra, Cocos nucifera and sugarcane was shown to be 95.79 d,105.72 d,109.04 d, and 152.37 d, respectively. But the development on the artificial diet included the main ingredients of O. regia, A. Alexandra, C. nucifera was shown to be 124.24 d,131.84 d,134.87 d at the same stage, respectively. The body size of adult of R. ferrugineus reared on semiartificial diets (24-30 mm) was more uniform than fed on natural stems. But the weight of eggs was not significant difference. Then the survival of egg stage was shown to be 92.29%. Although this survival rate was lower than fed on natural stems, there were not significant differences. The survival of larval stage was only 44.44%. But there was lower survival on palm and sugarcane stems, and it was shown to be 37.78,30.71, respectively. The survival of pupal stage (97.50%) on semiartificial diets was higher than natural stems. Based on these studies, we concluded that the natural stems for artificial rearing of R. ferrugineus could substitute for semiartificial diets.
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