Abstract:Soil - bag hydroponic culture was conducted together with ordinary soil pot experiment to study the relationship between rica oranging physiological disease and Si, Fe in red soil solution. It was found that compared with red soil solution without rice plant, Si/Fe of that with rice plant decreased while Si/Fe of soil-bag hydroponic culture increased. Electron probe analysis showed that the soil pot treated rice root had very high Fe peaks in outer cell wall of epidermis while very low or none Fe peaks were found in soil-bag treated rice root.Thecause for Si/Fe rising of soil - bag treatment and its role on correcting the physiological disease were discussed.

Abstract:In the presenl paper, two species of Scymnus kugelann from Hubei Province, China are described as new. Scymnus (Neopullus) thecacontus, Scymnas (Pullus)ancontoplyllus.

Abstract:本文记述云南省西双版纳的缨翅目(Thysanoptera)管蓟马亚科(Phlaeothripinae)共31种,其中发现1中国新记录种Xylaplothrips pictipcs(Bagnall)和2新种:Lecuuenia flavioornataZhang et Tong;Praepodothrips y?nanensis Zhang et Tong模式标本存华南农业大学昆虫标本室.

Abstract:This paper discusses the changes of tea plantation insect communities from January to December in Guangzhou by using the polar ordinal method (PO). Factors taken intoacoout included. Number of species, population density, diversity, degree of dominancy, uniformity of distribution, and similarity coefficient. The results showed that seasonal patterns of insect communities in tea plantations can be distinctly classified into four groups. The descending order of variations of insect communities was: January-February-March-December-November-August-April -October-September-July -May-June. The same conclusion was reached when applying Fuzzy clustering Analysis (FCA). This research indicated that FCA and PO used in forecasting changes of insect communities in tea plantations can reflect the real situatoin in the field.

Abstract:Based on life table and the interference iodex of population control,the effects of the different insecticides aod the different applications of Insecticides were evaluated in this paper. The effect of Dimehypo on the population of the paddy borer was the best,and Quinaphos was better than Dimilin- I.Tbe effects of different applications of Chlorodimeform was evaluated by the successive life table. The results showed that root-zone application was much belter than the spraying.

Abstract:In this paper, the state-space analysis method was used to study the effect of rice varietal resistance on the population system of the whitebacked planthopper, Sogatella furcifera (Horvath) (WBPH). The results in the experiment showed that the rice resistance to WBPH existed an adverse influence on nyraphal development, survival rate of the nymphs and on fecundity. Feeding on the various varieties, WBPH presented the different processes of oviposition. In rice field, the natural enemies made the adults died abnormally, and resulted in the decrease of the egg quantity of WBPH population dynamics could be forecasted by using the state-space analysis method. It was showed that rice resistance had an obvious suppression on the WBPH population, and that the effect of resistant rice varieties snduid be emphasised in Integrated Pest Management Programme.

Abstract:The tests of four essential oils against 4 species of storedproduct insects, Sitophilus zeamais, Tribolium casta-neum, Oryzuephilus surinamensis and Rhizopertha dominica,insimulated storehouse were carried out in Guangdong Province. The results showed that cassia oil at a dosage of 0. 2% by seed dressing kept the stored wheat free from damage by insects for as long as 8 months. Using a dosage of 0. 45 mg/cm2 to treat gunnysack, the essential oils from Illici-um verum and Clausena dunniana protected the wheat from being damaged by stored-product insects for 4 months, whereas cassia oil for as long as 8 months. The results of experiments in storehouse indicated that the combination of 15 ppm cassia oil caused 100% mortality of stored-product insects and 30 ppm malathion or 30 ppm cassia oil caused tested insects 89. 5% and 98. 5% mortalities, respectively.

Abstract:Eleven aggregation indices were used to analyze the spatial pattern of rice infested by the rice gall midge Orscolia oryzae (Wood -Mason)in paddy field in different Mages from July to August, 1990 in Debao county. The pat-lern dynamics were tested by Fuzzy clustering method. At the same time,the sampling techniques were also studied. The results showed that the distribution patterns were aggregated as the infested plant density was not more than 3 plants per hill .and became uniform distribution as the plant density was more than 3 plants per hill. The basic components of distribution were colonies and the distribution of the basic components was aggregate. It could be divided into mo kinds of spatial patterns:the low density is in early stages,and the high density is in late stages. The optimum sampling position is the tillering plants of rice. The Iwao's sequential sampling model and improved Iwao's sequential sampling model of the infested plants are:Where.T'0(n) ,T'0(n) is upper limit and lower limit of accumulated sillvershool numbers in the process of sequential sampling respectively ;n is sequential sampling n umber ;t is t-value for certain significant level.

Abstract:Diclazuril, a new anticoccidial drug, was studied for its efficacy against chicken coccidiosis in battery trials and floor-pen trials. The high anticoccidial activity of diclazuril against Eimeria tenella was confirmed by the anlicoc-cidial index (195. 6) in two baitery trials. The floor-pen trials indicated that diclazuril at a dosage of 1 ppm in the feed was highly effective against mixed infections of three major pathogenic species E.tenella, E. acervulina and E.maxima in preventing mortality, suppressing cecal lesions and oocyst shedding, and allowing for normal weight gains as well as feed conversion.

Abstract:This paper reports study on production factors such as type of condenser, the cutting-up of the branches and leaves, and their degree of dryness to determine how they affect the yield and quality of oil, in the process of cassia oil production.It was demonstrated that the oil yield was markedly affected by the type of condenser. Optimal conditions for distillation were to use N3 condensers, with semi-dried raw materials cut up in one-centimeter long pieces. The yield of oil was 1. 37 % , which had an aldehyde content of 90 %, while the type of condenser, how the branches and leaves were cut and their states of dryness fundamentally did not affect the aldehyde content.

Abstract:采用生物活性追踪法,从苦楝果实中分离得苦楝新醇(Ⅰ)、苦楝酮(Ⅱ)、苦楝醇(Ⅲ)、苦楝二醇(Ⅳ)、苦楝三醇(Ⅴ)、香草酸(Ⅵ)、香草醛(Ⅶ)和川楝素(Ⅷ),并根据波谱(1R,MS,′H—NMR,~(13)C—NMR)分析和理化常数测定确定其结构.其中Ⅱ、Ⅲ、Ⅳ和Ⅴ的21—H存在差向异构现象.生测结果表明,Ⅱ～Ⅴ和Ⅷ对菜青虫(Pieris rapae)有明显的拒食活性,Ⅷ还表现出明显的胃毒活性;Ⅰ、Ⅳ和Ⅶ仅表现出一定的拒食活性.

Abstract:Calli were induced from germinating seeds of indica rice ( Orgza saliva L. indica variety )" Qiuguiai 11" and the embryogenetic calli were selected and transferred to N6 liquid media in which embryogenetic cell suspension cultures were established after 6 months' subculture. Protoplasts were isolated from suspension cultures and imbedded in KpR agarose media. Without using nurse culture, the division frequency was 11.36%. The regenerated cell colonies were transferred onto N6 differentiation medium in which green plant formed. The plant regeneration frequency was 9. 4%.

Abstract:Changes of endogenous Cytokinins (CTK) during growth and development of Drassica parachinensis were investigated. The results showed that CTK existed in the growing tip, the flowering stalk and the it's base part. The content of CTK in the growing tip increased gradually to a small peak value before flower bud differentiation and then decreased gradually. At the beginning of the flowering stalk formation the CTK content in growing tip rapidly increased ;tgain reaching a big peak value during the early stage, and then decreased. The CTK content in the flowering stalk increased quickly from early to middle stage, and reached the biggest content. During this period, the plant and flowering stalk both grew rapidly.

Abstract:The initial results of the investigation on the vascular plant: resources of Ping Yuan County, Guangdong Province, are reported In this paper. There were found 183 families, 613 genera, 1182 species of vascular plants. A-mong them, there were I new species, 1 new variety and 23 precious, rare and endangered species. All sorts of economic plants were also analysed and described. It was concluded that the families with the most medicinal plants were more or less the same to the families with most species, the families with the most timber species were more or less the same as the typical families of the flora. The species which could be exploited and used were discussed too.

Abstract:Three species have been found new to Hainan Province while investigating weeds. They are:Alternantheru pungens H. B. K. , native to South America; Boerhavia erecta Linn. , reported from the Pacific islands and Xisha archipelago of China; Lindernia procumbens(Krock. ) Philcox, reported from the mainland of China. The plants grow on the cultivated areas. Alternanthera pmgens H. B. K. and Lindernia procumbens (Krock. ) Philcox are weeds. Their occurrence in Hainan Province warrants further studying.

Abstract:The present paper is a re poll of six new species and two new combinations of bamboo from Liangguang which Me Melocalamus gracilis, Bambusa semitecta, Sinocalamus recto-cuncatus , S. oldhamii f. revolutus, Sinarun-dinaiia papillosa, Phyllostachys cantonicnsis, Acidosasa bilamina, Pleioblastus palellatis.

Abstract:In this paper, the different effects of ail temperature and airflow velocity on the drying of sugar - preserved pineapple slices, were investigated by a convection airflow drying apparatus. A mathematical model for the dry-ing of sugar - preserved pineapple slices was developed.

Abstract:Chinese Chestnut Nongda No. 1 was bred from a mutant induced by fast neutron radiation of Chinese oil chestnut branches in Yangshan County. It had the good economic characters of a high and slaWe yieding variety which included early maturity, dwatfism and potyseetied involucre. The fruit ripening period was from late August to early-September. The average height and crown diameter of eight-year old VM1 trees were 3. 30 m and 2. 70 m respectively. The mean and maximum value of individual seed yield were 2. 8 kg and 10. 7 kg respectively. The fruit quality was excellent and the characters were stable. It was appraised as a provincial achievement in 1991 and has been planted to 100 hm2.

Abstract:Sinocalamus latiflora (Munro) McClure (Bamboo) has considerable economic importance. Its shoots can be eaten as food and its mature culms used as industrial material. Callus formation from explants of bamboo sprout sheath was induced on Murashige & Skoog basal medium supplemented with the 2, 4-D 4-8 mg/1 and kinetin 3 mg/l and agar 0.7%-0. 8%. Calli could grow continuously when they were subcuitured on the same medium or medium supplemented with other nutrients and hormones.

Abstract:The target -type seedling feeder, which is normally used in the rotary-vertical path type power rice transplanter when transplanting pulled-up seedlings, is simple in structure, but the path of the seedling feeder not so satisfactory. It is assumed now that the moving path of I he feeding fork is a curve of the linkage bar. The path equation is worked out according to the geometrical relationship between the bars of the crank and bar linkage mechanism. The mechanism achieving the path has been determined by using the random direction research method of the direct research method with constraints. The seedling feeding capability of the transplanter was improved.

Abstract:Based on the 59 references issued abroad in the past 25 years(1968-1991), this paper summarizes fully the history of development and the present status of research on veterinary echocardiography and introduces briefly detecting equipments, techniques and normal echocariography values of the horse, cattle, dog, cat, swine, and sheep. Brief description of the clinical application of echocardiography in diseases such as endocarditis in domestic animals and so on is also included.