| Anastatus sp.(Hym.: Eupelmidae) is a dominant egg-parasitoid of Tessaratoma papillosa Drury (Hem.: Pentatomidae), which is one of the important pests of litchi and longan. Since the Chinese scientists firstly discovered it in early 1960's, studies on the bionomics, mass rearing and utilization of Anastatus sp. have been conducted. Great economical, ecological and social effects have been obtained in Guangdong and Fujian provinces. The artificial diet for mass rearing Anastatus sp. is an effective approach to solve the limitation of alternative host, perny silk worm, and enlarge the utilization of this egg-parasitoid. Although it showed some promising results, there are still some problems, such as the lower parasitism and instability etc. to be solved. Experiments had shown that chemical attractant, or called as kairomohe, was a fundamental element affecting the behaviors of parasitoids in their habitat orientation, host exploration and oviposition. In order to improve the mass rearing Anastatus sp. in artificial diet, some biological characters and its antennal sensilla were observed and reported in this paper.The general antennal structures and sensilla of Anastatus sp. in both male and female were observed under a light microscope and by scanning electron microscopy. The general antennal structures are commonly seen within other chalcid wasps except for a specialized 'explore area' on the ventral apex of female antenna. From the observation of antennal sensilla by scanning electron microscopy, 9 different types of antennal sensilla of Anastatus sp. have been found and described. The different antennal sensilla are: Sensilla trichodea, Sensilla chaetica, Sensilla placodea, Sensilla ampullacea, Sensilla campaniformia, Sensilla basiconica, Sensilla i-type, Sensilla falcate, Sensilla long cylindrate. The number and distribution of each type of sensilla is different between male and female.The test of orienting behavior, 2-armed airflow olfactometer was used. The material (or attractants) used in this experiment including: 5 species of plant leaves (litchi, longan, mango, Chinese olive and Magnolia), 4 kinds of acetone solutes of litchi stink bugs (grinding body, scent glands liquor, excrements and body shell), 6 kinds of egg substances from litchi stink bug and tussah (whole eggs, egg plasma and egg shell), 3 kinds of extracts from tussah eggs extracted by acetone, alcohol and n-hexane (the extracts called as: acetone-tussah egg extracts, alcohol-tussah egg extracts, n-hexane-tussah egg extracts). The results revealed that the lure effects of litchi leaves, longan leaves, 3 kinds of acetone solutes of stink bugs (grinding body, scent glands liquor, excrements), 3 kinds of substances from tussah eggs (whole eggs, egg plasma and egg shell) and 3 kinds of extracts from tussah eggs extracted by acetone, alcohol and n-hexane were obviously better than others.In the test of exploring and parasitizing behavior of Anastatus sp. in culture dishes, itis shown that acetone- tussah egg extracts has a best lure effect among the all materialtested besides the 2 host eggs of litchi stink bug and tussah. The effect of alcohol-tussah egg extracts and n-hexane-tussah egg extracts is taken second place. A similar parasitizing result has been obtained again in the experiment of artificial diet.In addition, some biological characters of Anastatus sp. reared from artificial diet were studied. The adult life spans and fecundities of Anastatus sp. showed a degressive trend in accordance with the longer time of cool storage. When the pupae of Anastatus sp. were kept at 10 for 0, 30, 60, 90 and 120 days, their adult life spans were 37.8, 17.2, 24.0, 1.39, 3.5 days in parthenogenesis and 38.7, 27.0, 26.3, 19.0, 2.2 days in gamogenesis, the fecundities were 169.2, 119.3, 38.2, 43.5, 2.3 eggs in parthenogenesis and 227.5, 175.2, 69.7, 48.7, 2.8 eggs in gamogenesis respectively. Their life spans and fecundities can also be affected by humidity and supplementary nutrition. Under the condition of 75% RH and 40% RH, t...
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