Abstract:Some inducible antibacterial peptide (AP) were developed from the haemolymph of Chinese oak silkworm,Aniheraea pernyi pupae.The AP had broad-spectrum inhibition on bacteria such as wilt disease,Pseudomonas solanacearum of tobacco etc.The AP-D has been isolated and its amino acid sequence has been determined (36 peptides).We designed the nucleotides sequence of AP-D gene (122 bp) and synthesized by by DNA synthesizer.The M13 mp8 DNA was ligted with AP-D gene and transformed into E.soft JM103.The recombinant plasmid cut with Sai 1 and co24 plasmid containing CaMV 35S promotor cut with Xho I were ligated and transformed into Agrobacterium tuonefaciens by triple mating method.A Selected medium containing Km,Cm,Spc and Str was used to select the colonies which bad insert with AP-D gene.A.turnefaciens containing AP-D gene was used to infect the leaf dics of tobacco.After 4 weeks,we found some plantlets differentiation at the redges of leaf dics.These plants were resisted to Km,the nopaline detecton and Southern blot hybridization with AP-D gene probe showed that AP-D gene had been integrated into tobacco plant.The expression product should detected with its monoclonal antibody.We are now studying this in order to introduce the AP-D gene into to bacco plant.

Abstract:The influence of labeled 15N urea applied respectively with different kinds of organic materials (lignin,cellulose ,starch and rice straw ) on rice growth and nitrogen uptake by rice was studied in a rice pot experiment with soil pre-flooded for 30 days.When urea was applied,1.with lignin,no undesirable rice growth (spike number,straw or panicle dry weight) was observed and the response of rice was not related to the C/N ratios of mixtures) 2.with carbobydrates (cellulose,starch) and rice straw,the retarding effects on rice growth were indeed.Under same C/N ratio conditions,as for these retarding effects,the performance of rice straw was similar to that of cellulose) but the starch presented stronger one than cellulose did although the effects of cellulose plus urea in high C/N ratio were bigger than those in lower C/N ratio.When urea was applied alone,its nitrogen recovered by rice plants or residual in soils were respectively observed as 49.9%or 26.22%.These values were not correspondingly much different with those obtained by mixation of urea and lignin.The addition of other organic materials ,however,would enable urea-N to obtain incerase of its residual in soils and decrease of its recovery by rice plants or losses (except CcN-10:1) although the mixation of rice straw presented the highest urea-N residual (58.8%) in soils,or the lowest value of its recovery (26.8%) and losses (14.4%).In addition,the comparison of organic materials resulted in undesirable urea-N recovery by rice plants was observed as rice straw (C/N ratio 25)>cellulose (C/N ratio 25),starcn (C/N ratio 10)>cellulose (C/N ratio 10).Application of all fertilizers would increase soil-N uptake by rice.When urea was applied alone,437.3mg/pot of soil-N (as 59.5%of total N in rice plants) was absorbed by rice.This value was not significently diferent with those in the treatment of urea plus lignin ,as well as in the urea plus rice straw treatment though its soil-N uptake reached 72.3% of total N in rice plants.Nevertheless,mixation of cellulose or starch would reduce soil-N uptake by rice and increase its proportion of total N in rice plants a little.

Abstract:When urea was the only source of nitrogen for hydroponic culture of vegetables,1.under controlled temperature ,no significant transformation of ruea was observed in the deionized water-made nutrient solution when no crops were grown ,but significant one was presented in the same solution after growing vegetables.The higher was the temperature,the faster was the urea transformation.The solution's pH was ranged between 5.0-6.3 during this period;2.under room temperature,the urea was significantly transformed and its ammonification and nitrification were almostly presented at the same time in the nutrient solution made by tap water or deionized water,respectively.At the end fo the 3rd week,about 90%of supplied urea-N was transformed into MM4+-N and NO3--N,each one was accounted for about one half of the transformed urea while the pH of both nutrient solutions were ranged between 4.2-6.9.when lettuce (Lactuca saliva L.) and water spanich (Ipoinoea aquatica) were respectively grown in the nutrient solution with urea as its only N constituent,1.no undesirable response of water spanich was obtained,but damaged symptom was appeared in the lettuce body;2.the pH of solution could be dropped down to below 4.0;3.the urease activity in the roots of water spanich was lower than that of lettuce.

Abstract:The present paper is a review of Chinese Scymnus Kugelann.The subgenus S.(Colendonus) Bielawski (1973) and 7 species are synonymized here,and the validity of the subgenus S.(Parapullus) Yang (1978) is recoginzed.Up to the present,82 species have been known to China,of which 3 are new records for China.Finally it provides a list of China species with their distributions.

Abstract:During the study of the numerical taxonomy,60 OTUs and 18 characters have been studied and analyzed by means of Q-classification and R-classification,respectively,3 methods of numerical taxonomy and 11 operations have been analyzed.The best method for Q-cluster of Meloidogyne is the median cluster based on the distant of Tschebyscheff,by which the phenetical relationships of the species are graphically summerized and directly perceived and for R-cluster is median cluster based of distance of P.C.Mahalanobis,by which the phenetical relationship between the quantitative characters,the qualtative ones and between the quantitative and the qualitative are well expressed.It has a similar result as the one of the stuby on weights.The study results of Q-cluster show that there is no differenciation of genus among 60 OTUs between unit distances (interspecies) ,the genus Hypsoperine should belong to genus Meloidogyne.Next,H.acronea and M.acronea not gathering in a group until D=400,probably should not be the same species but two individuals.In addition,M.incognita wartellei and M.incoginta meet in a group only on D=20,that means they have an rather close relationship.

Abstract:Some inducible antibacterial peptides were developed from the immunized haemolymph of Chinese oak silkworm ,Autheroca pernyi by injecting with Escherichia coll.Antibacterial peptid hed a strong inhibitory effect on the pathogen of rice leaf bacterial blight disease,Xanthomomas compestris pv aryzaeObservated the ultra structure of X.Oryzoe treated with antibacterial peptide by electromicroscope.The results showed the primary target of antibacterial peptide was against the membrane of cells,after 10-30 min the cell wall was be-stroied and the intercellular substances were pressed out of cell subsequently.Different ratio (1:10-200) mixture between the immunized haemolymph;suspension of X.oryzae(106cell/ml) were used to infect the leave of seedling or booting stage of rice.After 20 days,investigated the average lenght of leaf spot infection and counted with variance analysis.The results showed antibacterial peptide from immunized haemolymph had a distinct infectivity effect on the X.oryzae

Abstract:A bioassay of the crude extracts,as well as its fractions of different organic solvens partitions of A.nipponensis against four species of insect pests were carried out in the laboratory.The results showed that the methanol extract and its chloroform fraction presented a significant activity of growth and ecdysis inhibitory as well as antifecdant action against the larvae of Pieris rapae L.Plutella xylostella L,Prodexia likra and Mythimna separata Walder.As to the 5th-instar larvae of P.rapae,their antifeeding median concentrations (AFC50)of the methanal extract and its chloroform fraction were 0.31 %and 0.12%,respectively by the methed of the leaf disc tests,and their effective median dosage (ED50)of growth and ecdysis inhibition were 1.36mg/g and 0.34mg/g,respectively in quantitative feeding tests.For the 3-4th instar larvae of P.xylostella which are very resistant to the conventional insect-cides,the chloroform fraction of the crodc extract were very effective and its AFC50was 0.23% ,and its EC60 were 0.29% by feeding and C.22% by topical application.The servival adults were inhibited in oviposition.This study indicates that the main insecticidal priciples of the extracts exist in the weak pole parts.

Abstract:The resistance to Nilaparoda(BPH)in 4 rice varieties at 30,45,60-days old plants and the correlations between the content of various free amino acids taken in rice sheath and 4 resistant parametrics including damage rating,amount of honeydew excreted;nymph survival and fecundity were studies.The results indicated that the total content and the content of mainly free amino acids in susceptible variety TN1 were higher than resistant variety 7105 in different growth ages.Generally the total content of free amino acids in the moderate resistant varieties Baosyan 2 and Fubaoai 21 were higher than in 7105 but lower than in TN1.The positive correlations significantly existed between the content of 4 amino acids (phenylalanine,Valine,glutamic acid and boleucine) and 4 resistant pararnetrics,also existed between the content of other 3 amino acids (asparagine,aspartic and leucine ) and 3 resistant pararnetrics.Otherwise,the result of feeding test showed that 5 kinds amino acids (asparagine,valine,leucine,serime and phenylalanine) have a significant pgagostimulative effect on the BPH fedding.

Abstract:Based on the studies of life tables of diamondback moth (DBM),Pbatella xylostella (L.),"perasitization" at the pupae stage were established as the most important mortality factor for the population of DBM.The new style of insecticides (chitin synthesis inhibiting insecticide) IKI-7899 which was sprayed at the concentration of 50 ppm were promised to be favourable to the parasites,and could provide effective control of the DBM,with 98.80%of the control efficency for the larvae and 0.0009 of the population trend index (I),while conventional insecticides cypermethrin (200 ppm) and dichlorvos (1600 ppm),which were mixed used for four sprays at an interval of 4-5 days,in the whole generation were harmful to the enemies and could not effecctively control the DBM,with 62.82% of the control efficency and 9.2769 of the trend index (I).

Abstract:By mesns of rotation composite design of quadratic regression,5 mathematical models were constructed in the present paper to study the relationship between the preyed numbers of the rice leaf roller and its predators.The models had also been corrected with several years data investigated in the paddy field.According to these models,the preyed numbers of the rice leaf roller could be estimated by its densities and each predator.Therefore they could be used to forecast the population dynamics of the rice leaf roller.

Abstract:The control suitable occasion of the diamondback moth (DBM) was studied in Guangdong province.By means of rotation composite design of quadratic regression ,two methematical models were constructed to study the influence of the DBM on yield and quality of false pakchoi.The results showed that the sensitizing phase of false pakchoi to DBM was in the 6 to 9 lesf-stage.The results in experiment of the DBM selectively laying eggs showed that the most eggs were found in the 4 to 5 leaf-stage of false pakchoi.Therefore,the 6-9 leaf of false pakchoi was considered as suitable occasion for controlling DBM.

Abstract:The most important nematodes on the Banana plantation of south China Agricultural University were reniform nematodes (Rotylenchulus reniformis),rhabditids (Rhabdictis spp.) and spiral nematodes (Helicotyleuchus dihystera).There were different trends on the vertical distribution of varide species of nematodes in the soil.Rhabdictid distributed mainly fron o-10cm and spiral nematodes from 11-20cm,but reniform nematodes from31-50cm.Reniform nematodes showed distinctly seasonal fluctuation.The highest population density of them occurred in early May and the lowest in laterFebruary.Population fluctuation was closely correlated with the accumulated temperature and soil moilture content.Rhabditids and spiral nematodes did not appear a distinct,seasonal fluctuations.

Abstract:The imterations between artificial vegetable community texture and the searching behavior of the dia-mondback moth (DBM),Plutella xylocella were discussed with chemical ecology association in this paper.The texture implies the individual crucifers density,dispersion,and species richness.An understanding of DBM searching mechanism may be used in current DBM management practice to disign agricultural systems that are less likely to be attacked by this pest.

Abstract:This paper is a review article outlining the present state of research into the biotypes cf brown planthopper (DPH),in which the following aspects of these studies are described:1) Occurence of biotypes:2) Specificity of biotypes:3) Formation of biotypes.While cultivation of resistant rice varieties has proved to be highly effective on the BPH.their long-term stability is threatened by the appearance of prolific biotypes which can destory these varieties.Therefore,both major and minor resistant genes will be used in the present rice breeding researches for effective pest suppression.

Abstract:Genetic improvement of plant nutritional characters provides a new approach towards increasing the crop yields in unfavorable soil environments.The possibility of successfully breeding crops for nutritional characters depends on the knowledge of the genetics of the charaaters and their physiolegical-biechemical basts and the appecpri-ate application of breeding methodologies.This article briefly reviews the research developments of these aspects.The author also describe the perspectives of genetic improvemnt of plant nutritional characters and suggest possible research approaches for the future.

Abstract:This trial was proceeded in the experimental dairy farm at South China Agricultural University in 1991 and the primary coefficient of female control was successfully reached to 81.8%at an advanced level between the internal and outside the country.As a result of the trial,11 calves were born by 10 cows,including a twin of sexuallity at birth.It is of immense values to biological science and economy for this trial.It was found that it is possible for realizing of sexing sperm by treating of bovine semen with H-y antiserum IgG.It was also an evidence of using Density Gradient Centrifugation of Sucrose solution and Fluorescent Staining for inspectation of the effectiveness of H-Y antiserum IgG.We observed that the H-Y antiserum IgG showed marked effect of inhibition on Y-bearing sperm,so that we can achieve a good result of sexing control in dairy cattle.

Abstract:从四川省阆中市蚕区捕捉的蓝叶甲(P(?)Baly)中分离到一种大型微孢子虫,孢子大小为4.75±0.40μm×2.85±0.25μm,孢子的超微结构及在家蚕体内的发育周期符合Nosema属的特征,对家蚕有强的食下传染,感染家蚕后的经卵传染频率很低。

Abstract:This experiment deals With the Studies on degummibng loes of cocoon shell of Boabyx mari in terms of heredity and breeding ,and the results showed that there were differences between the various voltines,varieties and male and female silkworms among the same variety.There was no uniform tendency for the cotelation between the degumming loss of cocoon shell and whole cocoon weight,cocoon shell weight and cocoon shell ratio According to the estimation by Heymen model,the pararameters of degumming lossS of cocoon shell were D=1.8344.H1=0.2793,H2=0.2690.F=0.0798;in the besedicery cemponents of degumming loss of cocoon shell.additive componeat was the major one;ist derminant effect was controled by an iacomplese dorminat,major gene or by a group of them;its generalized heretability was 91.16%.while its special one was 82.21%.There was a significant difference between its general combining ability and apecial conbinging ability.Generally,it appeared to be negative to heterosis.Through the systemic hreeding and hybridisation in the selection test of degumming loss of cocoon,it was known that selection was effective,And the more idealistic method was to use the latter oae

Abstract:IP.this paper were investigated soil fertility factors,such as the quantity of microorganisms,the biochemical and enzymatic activities and the nutrient in the mixed forest of Picus massoniman and Caslanopsis fissa of Zengeheng Forest Farm,Guangdong Province.Among the 18 fertility factors investigated the annual average of 14 factors in the mixed forest is higher than those in pure forest of P.massoniaus.This shows that the mixed forest gets obviously higher fertility level of soil than the pure forest does.Comparing the mixed forest with the pure forest,the seasonal quantity and activities of microorganisms in soil are nearly equal to each other,but the nutrient and the enzymatic activities very differ.

Abstract:Based on the field experiment,the description of the vertical distribution of immature staffs of the dia-mondback moth,Phtella xylosella within some cruficerous vegetables that are flowering Chinese cabbage,Chinese kale and broccoli was given.The results showed that the eggs were mainly laid on the 2nd leaf and the larvae concentrated in the growth point and the youngest leaves,while the pupae were all distributed within the plants.In the other hand,the movement behaviors of this pest within plants and its mechanism were disscussed in this paper.