Electrophysiological effects of methothrin and deltamethrin on theexcitatory junction potentials (EJPs ) of the Drosophila larval neuromuscular junction were recorded by using an intracellular microelectrode. M ethothrin (1.49 x10^-8mol/L) caused high frequency spontaneous EJP spikes and repetitive discharges, while deltamethrin (1.0 x 10^-8mol/L) did not. This study revealed that methothrin could produce hyperexcitation (Type I action) in the peripheral nervous system of the Drosophila larvae, but deltamethrin did not (Type II action ).Combined application of methothrin and deltamethrin resulted in a compositeaction type, which showed both Type I and Type II action on spontaneous or stimulated EJPs. The frequency and duration of repetitive discharges or spontaneous spikes in the combined treatment were changed according to the proportions of methothrin and deltamethrin. This suggests that there may be a noncompetitive interaction between methothrin and deltamethrin during their joint action on the peripheral nervous system of the Drosophila larvae.

The activities of three serine proteases in thc midgut of Helicoverpaarmigera larvae were partially characterized. The enzymes were an active alkalinetrypsin-like enzyme with maximal hydrolysis of benzoyl arginine p-nitroanilideat pH 10.50 or higher, a weak alkaline trypsin-like enzyme with maximalhydrolysis of tosyl-L-arginine methyl ester at pH 8.50～9.00, and achymotrypsin-like enzyme with maximal hydrolysis of benzoyl- L- tyrosine ethylester at pH 8.50～9.00.Total proteolysis, measured by using azocasein, hadamaximal activity at pH 10.50 or higher. Ca2+had no activation effect on larval proteases, but Mg2+activated the weak alkaline trypsin-like enzyme. The inhibition with phenyl methyl sulfonyl fluoride and tosyl- L- lysine chloromethyl ketoneto the weak alkaline trypsin-like enzyme activity was greater than that to the active alkaline trypsin- like enzyme activity. The tosyl- L - phenylalininechloromethyl ketone was not only the inhibitor of the chymotrypsin-like enzyme,but also the activator of the weak alkaline trypsin-like enzyme. Comparison between the insect protease and bovine counterpart protease revealed difference in inhibitor sensitivity. Ovomucoid trypsin inhibitor that inhibited bovine trypsin had no effect on insect trypsin-like enzymes. Soybean trypsin inhibitor had great inhibition on both insect and bovine proteases.

The generation of adult rectum and functional differentiation of rectalpapillary cells in the black cutworm (Agrotis ypsilon ) were studied with light andelectron microscopes. Attention has been paid on their histological and cytotogiralchanges in sixth instar larvae, prepupae, pupae and adults. The results are summarized as follows: 1. Adult rectum was generated after the larval cryptonephridial complexdegenerated. Larval rectal cells rapidly divided, reconstructed and differentiated during the prepupal and early pupa 1 stages so that adult flat rectum cells and discal rectum papillae were formed. 2. Adult rectum papilla was discal and consisted of five layers of cuticle intima, papillary cells, basal lamella, muscle and peritoneal membrane. Papillary cells were divided into four types: cap cell, tracheolar cell, netty cell and discal base cell. 3. In our study it is found that adult rectum expands owing to the papillary volume enlarging. A series of delicate constructure enable papillary cells to enlargein volume and provide oxygen and nutritent supply

Features of some sensory structures including sensory nodules and sensorypits of adults of 18 species belonging to 11 genera and their nymphs of 2 species ofTingidae (Hemiptera- Heteroptera ) are observed under the scanning electron microscope and compared among the genera. Based on the main features of the sensorystructures observed, the 11 genera under observation are differentiated into 6groups. Taxonomic significance of the differences of the sensory structures ingeneric level are further provided. These differences are considered to be new anduseful features in identification of the genera, and also of reference values in thatof some species within each genus. Phylogenetic development of the sensory structures of tingid insects are investigated and some proposals are made.

Rice variety could influence the development, survival and fecundity of the parasitoid Anagrus nilaparvatae directly through the physical structure of the plant or indirectly through the eggs of the parasitoid's host, I.e. the brown planthopper,Nilaparvata lugens (Stal). There was a highly significant negative correlation between the emergence rate and fecundity of the parasitoid and the silicious cell density on the back of leaf sheath of rice, and the fecundity andbody size were very significantly positively correlated with the egg size of N. lugens which was influenced by rice variety. The component analysis of the index of capacity for population increase of the parasitoid showed that the main factors affectingthe capacity for population increase of the parasitoid were different fimong rice vaileties. This implies that the effects of rice varieties on the parasitoid are resultedfrom multi- factors.

Imidacloprid, a nitromethylene analog1-(6-chloro-3-pyridylmethyl )N-nitroimidazolidin-2-ylideneamine, is a highly effective systemic insecticide,against the brown planthopper, Nilapavarta lugens (Stal), (BPH), as shownboth in laboratory and field tests. The LD₅₀ of Imidacloprid (technicalImidacloprid>96%) for contact activity against the 3rd and the 5th instarnymphs of BPH was 2.55 x 10^-5μg/nymph and 6.78 x 10^-5μg/nymph respectively.Regressions of mortality probit (Y) against logl0 of contact concentration (X) of the 3rd and the 5th instar nymphs were Y=5.6231+1. 0486X and Y=5. 2091+1.2389X respectively. Imidacloprid did not show only as a highly contact insecticide but also an excellent stomach toxicant against young and mature nymphs and adults of BPH. Field trials of foliar application in paddy fields of Jurong and Wujiang Counties with 10% Imidacloprid WP, at a rate of 15 or 30g a.I./hm².Against BPH, achieved stably high (>90% control effectiveness) population sup pression over 40 days after treatment. The high insecticidal fficacy withImidacloprid as foliar spray for BPH control in paddy fields was basically manifested into three effective aspects, including rapidity (1～3 days after treat ment),sustainability (4～10 days of treatment) and long residual effect (11 days after treatment). The field trials with Imidacloprid also displayed good selectivity between BPH and its natural enemies. It was specially safe to spider community in paddy fields.

The key to remove hidden danger of subterranean termites in dykesand dams is how to find out the nests. Our study indicates that the subteraneantermites nests can be exactly discovered for the underspace positions by usingGrand Penertrating Radar, mastered thief image features and the calculation forthief deepth and size. As the method has got a higher effieciency and a highergeometric resolving power, and image showing in right time, it is regarded abreak through in the field of the subteranean termites nests detection. It can beconsidered of great value for application, and has good prospect in its development.

Indian meal moth Plodia interpunctella larvae are freeze-susceptible.In winter, they avoid freezing by lowering supercooling point. It is wellknownthat ice nucleating active bacteria can significantly elevate the supercooling point ofplants, resulting in promoting frost injury. Our study also proved that bacterialice nucleators can significantly elevate the supercooling point of Indian meal mothlarvae. In the control group, the mean supercooling point is -17.6℃. After treatment with 0.Lg and lg of bacterial ice nucleators mixed to lkg of flour, the meansupercooling point elevate 12.8℃ and 13.6℃ above the control respectively. Results of this study support the idea that bacterial ice nucleators may be used for the control of freeze- susceptible insect pests in the winter.

This paper deals with the injuries caused by Tomicus piniperda to theshoots of Pinus yunnanensis in shoot-feeding period in Kunming region of China.Information on its biological characteristics including sex ratio, mating, feeding preference and habit, hibernating and ovary development is presented and discussed.The shootfeeding period in Kunming started during May and lasted to Marchthe next year, in which each beetle bored 3 to 6 shoots. Most damaged shootswere the current shoots with 7Drosophila (Drosophila)7～8.5mm diameter. The same shoot could bedamaged several times, but frequently two times. The entrance hole was about3～4 cm far from the shoot tip. Mating was observed during shootfeeding and the mating rate increased progressively with ovary development. The developmentduring the winter season slowed down due to low temperature. Successfulhibernation was observed for all stages.

Oestrus ovis is an insect of cosmopolitan distribution and nasal sheepmyiasis due to its larval injury widely occurs in the pastures of most countries of the world. We have carried out a series of studies on its bionomics since 1990.This report concerns some results of basic importance including the interrelation between adult emergence and the environment factors, the location of larvae in the soil, the pupation posture, the pupation in relation to the growth level of the larvae, the adult activity, its life- span and sex retio.

This paper describes a new species of grasshoppers from Shennongjia,Hubei province. The type specimens are preserved in the Department of Biology,Shandong University.

Two new species of Acridoidea from Guangxi, China are described in the paper. The type specimens are preserved in the Institute of Biology, GuangxiAcademy of Sciences.

In this paper a new species of Heterogastrinae is reported, I.e.Heterogaster alashanicus Liu et Zheng sp. Nov. The type specimens are kept inDepartment of Biology, Nankai University.

Phaonia fuscula

A new genus and a new species of M ycomyiinae are herein describedas new to science. The type specimens are deposited in the Insect Collectionsof Zhejiang Forestry College.

Aoki (1970) erected the genusCosteremus with C. ornata Aoki as the type species. Fujikawa and Fujita (1985)described the second species C.Yezoensis. The present paper deals with a new species of Costeremus from China.The genus is recorded for the first time from China, as well as from the outsidearea of Japan.

Insect immune response to bacterial infection results in the synthesis ofantibacterial proteins in its hemolymph. This paper reviews the recent progress inthis field, concentrating on the characterization of the antibacterial proteins and the potential significance of these proteins. The most potent character of the inducible antibacterial proteins is that they have the capacity to identify foreign objects, to attack them and protect the insect itself from being injured. Other progresses related to the nature of these proteins, such as their molecular iology, are also mentioned.