1989 Vol. 10, No. 2
A new micro-spreading technique for demonstrating synaptonemal complexes (SC) has been described.This method gives more consistent results than the routine spreading technique.Furthermore,the ease and speed should allow succssful application of this new simple method to field cytogenetic work.In addition,our results also indicated that both fresh and long-time frozen spermatocytes in liquid nitrogen can be used for preparing SC.
The cortical cirral-base-associated fibers (CF) in Euplotes sp.are:anterior longitudinal fibers (AF),posterior longitudinal fibers (PF),and radiating fibers (RF).Among them,the PF of frontoventral cirri (FVC) base are generally longer and thicker;while the AF are smaller;and,the RF are the thinnest and smallestones.The AF of transverse cirri (TC) base almost spread through the whole cortical region of frontoventral and transverse cirri (FVTC);and their RF are thinner- and smaller.Similar fibers,base-associated with different FVC,are different in size and shape.They extend from their cirral-base in various orientations,towards crtical cytoplasm,with apparent polarity and asymmetry.The fibers from FVTC base are heavily entangled,forming a strong net-work of base-associated fibers in their cortical region.During morphogenesis of Euplotes sp.,when the primordia of TC developed a bundle of thick cilia buds,extending towards the cortical fissure,the AF buds of TC primordia,PF buds of FVC primordia,and their RF buds,were developed successively.The fiber buds of left column cirral primordia developed first,then,developed those of the right column.The order of fiber material growth in coincidence with the development and differentiation of new cirri primordia.Also,in the formation of PF of FVC bases and AF of TC bases,polarity and orientation are displayed,I.e.,the directions of fiber material growth are opposite to thar of their corresponding new cirri migration.Old CF are doomed to degenerate during morphogenesis of Euplotes.It is supposed that their degenerating process are related to the gradual lose of old cirris functions during cell differentiation.
The present paper describs a new species of Protura,which is representing a new genus of Berberentomidae.All the specimens were collected from Zunyi,Guizhou Province,by Tang and Jin in Oct.1985.The types are preserved in the collection of Shanghai Institute of Entomology,Academia Sinica.
1989, 10(2): 107-114.
1989, 10(2): 115-122.
Combining cell synchronization in vitro and bromodeoxyuridine (BrdU) incorporation in early synthesis phases and late synthesis phase of cells of Ctenopharyngodon idellus,two kinds of chromosome patterns of replication banding,R- and G-bands were gained after chromosome preparation were irradiated in warm CaCI solution by UV and were stained with Giemsa.Some spreads lengthcncd in late-prophase and prometaphase show more numbers of bands and characteristics of higher resolution.Analysis of G-banded karyotype showe that there are four pairs of chromosomes with satellite.A tentative idiogrammatic representation of G-banded karyotype of Gtenopharyngodon idellusis proposed.The significance,techniques and possible meehanism of chromosome banding of fish are discussed.
This paper established new formulas for determining group density of female adult lac insect based on its characteristics of group distribution on host:(1)N=4/Πd2,(2)N=1/D2,(3)N/(4+π)/2πD2,those formulas can calculate the confidence interval and average value of group density of female adult lac insect.Test results has shown new those formulas ane more accurate,more simple and convenient than the traditional method for determining group density.
1989, 10(2): 133-138.
Activities of phosphomonoesterase and nucleases hydrolysing RNA and DNA were presented in a solution of the crude venom from a spider (Lycosa singoriensis) collected in Xinjiang Region,China.The substrates for assaying these enzymes were 4-nitrophenyl phosphate disodium salt,3 terminally 32plabellod RNA and nonlabelled DNA respectively.After incubation of RNA and DNA with the venom solution,the products were detected by polyacrylamide gel or agarose gel electrophoresis.
This paper deals with a preliminary analysis on the cestodofauna of birds from Bai-Yang-Dien Lake,Hebei Province and Tai-Hu Lake,Jiangsu Province,China.Some conclusions are drawn as follows:1.There is a close relationship between the faunal distribution of the cestodes of birds and that of their hosts,since quite a number of cestodes show higher host-specificity.2.Kunds of hosts having nearer relation are parasitized by the same kinds of cestodes of kinds of cestodes having nearer relation.Based on this fact,we supposed that the host affinity can be demonstrated according to the hosts having same species of cestodes or having sibling species of cestodes.On the contrary,we can also infer the evolutionary advance of the cestodes form the evolution of their hosts accordingly.3.Comparisons are made of the cestodofauna of birds of the order Anseriformes collected from the two regiong-Bai-Yang-Dien Lake and Tai-Hu Lake.The results show thas kinds of cestodes of birds at the overwintering area (Tai-Hu Lake) are much more in number than those in the migratory area (Bai-Yang-Dien Lake).4.In Tai-Hu area there are 20 species of cestodes of birds,8 species of them are northern form,11 species are stochastical form,and one remains undecided.Ggographical distribution of the cestodes of birds in this area indicates that 4 species are local kinds,4 species are cosmopolitan,and one is widespread species in the Eastern Hemisphere.
The present paper deals with the biology of wasps Vespa velutina auraria Smith,V.tropica ducalis Smith.In Kunming they could have three generations a year and overwinters in the holes of trees and soil.These Wasps complete their life cycle in laboratory at 14-15℃,the relative humidity at 43-89% between 33-53 days,in which the egg stage 9-15 days,the larval stage 10-18 days,and pupal stage 15-20 days.The longivity of workers is 24-142 days,and 4-60 days for males.The queens emerge in March and nest-building in April-May.They only do two times of nest-building in their life cycles,first,is bencath soil surface,usually in abandoned rodent burrow,second,on the tree,but for somes,their life-cycles and all within the soil.Nests are typically built in the spring by a single female.The first offspring are all workers,mating of the new queen with the males in October-November,and then the inseminated queens hibernate in the last ten-days of November.The Wasps could build their nests under the control of artificial conditions.Their important natural enemies are the parasites,Stylopidae and Tachinidae.
1989, 10(2): 163-168.