| Herse convolvuli Linne is a kind of pest on sweat potatoes, and it has characteristics of fast growing, enormous propagating, and short week and full of abundant proteins.lt is a kind of excellent protein resource that needs to be industrially exploited. The study on some characteristics of Herse convolvuli Linne's biology and artificial rearing techniques is firstly carried out, and the main results are as following.1. Through the microscope we measured helmet breadth of Herse convolvuli Linne's larva, and the result showed that proportions of every two helmet breadths of neighboring instars are respectively as following. 1.687 (the second instar to the first instar), 1.650 (the third instar to the second instar), 1.828 (the fourth instar to the third instar), 1.787 (the fifth instar to the fourth instar), and the average is 1.738. The data above demonstrate that helmet breadth of Herse convolvuli Linne's larva is increasing on geometrical number.2. We measured body length of Herse convolvuli Linne's larva on precise ruler, and proportions of every two body lengths of neighboring instars are respectively as following. 2.03 (the beginning of the second instar to the beginning of the first instar), 1.85 (the beginning of the third instar to the beginning of the second instar), 1.63 (the beginning of the fourth instar to the beginning of the third instar), 1.92 (the beginning of the fifth instar to the beginning of the fourth instar), 1.87 (the end of the fifth instar to the beginning of the fifth instar), and the average is 1.86. The result shows that body length of Herse convolvuli Linne's larva is increasing at a certain proportion.3. Herse convolvuli Linne's larva weight is measured on electronic analytical scale, and the result shows that weight of the end of the fifth instar is ten thousand of that of the beginning of the first instar. The changes of weight are more evident at the fourth instar and the fifth instar. The proportions of every two weights of neighboring instars are respectively as following. 5.88 (the beginning of the second instars to the beginning of the first instar), 6.64 (the beginning of the third instar to the beginning of the second instar), 4.88 (the beginning of the fourth instar to the beginning of the third instar), 7.29 (the beginning of the fifth instar to the beginning of the fourth instar), 8.70 (the end of the fifth instar to the beginning of the fifth instar). Because Herse convolvuli Linne's larva begins to enter into the gluttony period after the fourth instar, and the appetite in the fourth instar is 11.13% of the gross appetite and the appetitein the fifth instar is 85.39% of the gross appetite.4. The soil about 10 to 15cm depth is put into the big glass crock to pupate for Herse convolvuli Linne's larva. We found that most of the pupa rooms are distributed at the 2 to 7cm depth under the ground, and the shape of the pupa room is elliptical and is slightly greater than the pupa. The long diameter and the short diameter are respectively 4.5 to 5cm and 3 to 4cm, and the density of the wall of the pupa room is evidently greater than the other soil surrounded, and inner-wall is slightly smooth. The pupa room has no apparent tunnel to the outside and is likely to be sealed.5. There are some description about the color pattern of Herse convolvuli Linne's larva, but it is mainly for the fifth instar larva. The paper probes into the color pattern of Herse convolvuli Linne's larva of all five instars, and we summed up the characteristics of the color pattern.6. The paper firstly reports two parasitic bees which have rather high parasitic rate on Herse convolvuli Linne's larva period at Changsha district, and they are respectively Charops bicolor (Szepligeti) and a species in Apanteles Foerster. The parasitic rate on the second generation of Herse convolvuli Linne is 85.0%, and the parasitic rate on the fourth generation come up to 97.6%. The species of the parasitic natural enemy, the parasitic course and symptom and the parasitic rate are...
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