Abstract:In 1982, based on three specimens (Y. H. Li 23096, 6052, K. T. Tao 15885)collected from Yunnan (Mengla Xian, Menglum), P. T. Li and Y. H. Li described a new species of the genus Marsdenia . Recently, after dissecting a flower of the hololtype and performing phytochemical analysis, we realized that this species was erroneously placed in Marsdenia , differring from the latter in a series of important morphological characters, and in fact represents a new genus ( Sinomarsdenia ) of the tribe Marsdenieae, which is described in the present paper.

Abstract:By means of state-space population model, the population dynamics and population control of Diamondback Moth(DBM) Plutella xylostella (L.) was simulated by adding the biological agents. In the vegetable field,by releasing Trichogramma( Trichogramma confusum Viggiani(= T. chilonis, Nagaraja,nec. Ishii), or spraying DBM granulosis virus(PxGV), or spraying Bacillus thuringiensis(B.t.), the indeces of population control( IIPC ) of DBM decreased in 0.2, 0.24, and 0.29 against the control respectively, but the index of population trend of DBM in control was as high as 29.3, the population of DBM still increased by control each one of the biological agents. In the field of spraying B.t. and releasing Trichogramma showed the complementary effect. In the field releasing Trichogramma, spraying PxGV and B.t. the population dynamics of DBM were simulated. The results showed that the DBM population were decreased in a low level even in the high index of population trend in control(table 2).

Abstract:Eucalytus exserta and E. urophylla are two important tree species of man-made forests in South China. Leaf volatiles of them had significant inhibitions on seedling growth of Raphanus sativa, Lactuca sativa,Leucaena leucocephala and Acaia mangium. In comparsion of allelopathic effects of the three fractions from the distillation of fresh leaves, the declining order was: water soluble unvolatile chemicals > volatile oil > water soluble volatile chemicals. Volatile oils of the two Eucalytus could completely inhibite the seedling growth of A. mangium when volatile oil concentrations are 0.2 milliliter per culture dish. Allelopathic effects of volatile oil decompositing in soil would decline very quickly within 15 days. After that, it would maintain a certain level with significant inhibition. The aqueous extracts of fresh leaves of the two plants showed inhibitory effects on seedling growth of radish and luttuce. The aqueous extracts of E. exserta also inhibited the seedling growthg of A. mangium. The aqueous extracts of E. urophylla inhibited the seedling growth of L. leucocephala.

Abstract:The allelopathic effects of aqueous extract of leaf and root exudates of Ilex macrophylla Bl. on the germination and seedling growth of 6 accepter plants,i.e. tea plant, radish, rice, cucumber, manybean, cabbage were studied. The study indicated that there are allelochemicals existed in aqueous extract of leaf and root exudates. Allelochemicals accumuted in soil can inhabite the growth of nearby plants if the concentration is high enough.

Abstract:Twenty kinds of extracts from 8 species of Asteraceous plants were tested for their light-activated toxicities against mosquito larvae in the conditions of the presence and absence of near-UV light.The results showed that the extracts from Tagetes erecta were highly phototoxic:The methanol extract,ethanol extract,both obtained by maceration, and the petroleum ether extract from the root,whole plant and the flower caused 100% of mortality to the fourth instar larvae of Aedes albopictus at the concentration of 0.1 g/L in the presence of near UV light while the mortalities caused were 70%,20% and 0 respectively in the absence of near- UV light. Similar results were obtained on performing the experiment with the fourth instar larvae of Culex quinquefasciatus .It was noteworthy that the methanol extract, obtained by Sohxlet method from the root was effective in either the presence or absence of near-UV light and caused 100% of mortality in the concentration of 0.1 g/L under both conditions.

Abstract:通过对斯氏线虫科Ｓｔｅｉｎｅｒｎｅｍａｔｉｄａｅ的ＳｔｅｉｎｅｒｎｅｍａｃａｒｐｏｃａｐｓａｅＡ２４品系及Ｓ．ｃａｕｄａｔｕｍ连续两年室内及２０ｈｍ２田间多点试验的研究结果表明：这两种昆虫病原线虫对钻蛀为害多种果树、林木、花卉的荔枝拟木蠹蛾Ｌｅｐｉｄａｒｂｅｌａｄｅａ、龟背天牛Ａｒｉｓｔｏｂｉａｔｅｓｔｕｄｏ和光盾绿天牛Ｃｈｅｌｉｄｏｎｉｕｍａｒｇｅｎｔａｔｕｍ幼虫具有明显的防治效果。Ａ２４线虫能对钻蛀性害虫作寻向移动，日平均水平移动距离（４０３±０７２）ｃｍ，进入害虫体内２～３ｄ可导致害虫死亡。线虫在虫尸内能够繁殖，在１４～２３℃、相对湿度８５％～９５％的室内条件下，每一个生活史周期６～８ｄ，其后代可继续找寻并攻击新目标。海绵吸附法田间施放昆虫病原线虫新技术，具有安全、高效、简单、易行的特点。

Abstract:１９９４年，在深圳发现兰花叶枯病，该病害对兰花的危害极大，通过对兰叶病组织的分离、培养、纯化、接种及交互感染试验，根据病原菌的形态特征和致病性测定结果，鉴定其病原为李属柱孢霉。

Abstract:Most members of cybocephalid beetles are predators which feed on the armored scales on fruit and forest trees. 8 species of Cybocephalus Erichson ( Cybocephalus nipponicus Endrdy Younga 1971, C. Pangi Yu et Tian 1995, C. dissectus Yu 1994, C. concavus Yu et Tian 1995, C. explansus Yu 1994, C. chinensis Yu 1995, C. mashanus Yu 1994 and C. guilinensis Yu 1995) collected from Hainan Island, China, were described and illustrated in this paper.

Abstract:The extant Guangdong flora should be treated as a relict of Late Cretaceous or Early Tertiary floras, which has endured a long history of geological development. The fossil plants were very rich in different strata of geological age, such as Bennettites, Baiera, Ginkgo, Cycas and Gigantopterides, etc. Meanwhile from the Late Cretaceous to Tertiary stratum of Guangdong (and SW Guangxi), ample plant fossil( or pollen fossil) were also found, such as Celtis, Betula, Carpinus, Pinus , Abies, and Cedrus ,etc., accompanied by features of broad leaved trees and needle leaved trees, all of them being indisputably related to the geological history of Guangdong. Thus it naturally indicated that they probably originated from subtropical mountain regions, or it may be traced back to Cretaceous, or earlier, and Guangdong was undoubtedly one of the cradles of the Cathaysian flora or the flora of East Asia.

Abstract:采用差速离心法纯化了鸭胚尿囊液中的减蛋综合征（ＥＤＳ－７６）ＷＰＤＶ２０５病毒并提取了病毒基因组核酸。选用ＥｃｏＲⅠ和ＢａｍＨⅠ两种限制性内切酶对病毒基因组ＤＮＡ进行双酶切处理，结果产生７个片段，在这７个片段中，只具有ＢａｍＨⅠ酶切位点的片段有２个，只具有ＥｃｏＲⅠ酶切位点的片段有３个，具有双酶切位点的片段有２个。将其中的５个片段分别插入到ｐＵＣ１８相应多克隆位点中，建立了ｐＥＤＳＶＢＥ１、ｐＥＤＳＶＢＥ２、ｐＥＤＳＶＢ１、ｐＥＤＳＶＢ２、ｐＥＤＳＶＥ５个重组子，并对这５个重组子进行了酶切鉴定

Abstract:对广东肾变病型鸡中分离致弱的ＩＢＶ Ｄ４１株Ｓ１基因ＰＣＲ产物作了Ｈａｅ Ⅲ酶切分析，发现其酶切产物与ＩＢＶ Ｍ４１的一样，而与美国肾变型标准株Ｇｒａｙ、Ｈｏｌｔｅ不同。根据国外用ＲＦＬＰ区分ＩＢＶ血清型的判定标准，Ｄ４１株应归属于马萨诸塞血清型，综合此分离株的其它特性，说明华南地区存在着ＩＢＶ变异株的流行。

Abstract:Aflatoxin contaminated groundnut cake ( GNC) was treated with sodium hypochlorite for detoxification.The treatment was at 0.25%,0.50% and 1.0% levels and samples stored at 25% moisture level and ambient temperature in sealed polyethylene bags. The durations of treatment was 24, 48 and 72 hours.The present experiment showed that sodium hypochlorite is an effective reagents for destroying aflatoxin in GNC. Both the level of chemical and treatment time were not important factors for detoxification in this trial and there were no significant difference between the different level of chemical and duration of treatment ( P >0.05). The treatment with 0.25 % sodium hypochlorite for 24,48 and 72 hours could reduce aflatoxin by 93.32%, 95.51% and 96.27% respectively.The destruction of aflatoxin in GNC was 94.82%, 93.82% and 96.65% for 1.00% of sodium hypochlorite treatment for the three treatment duration respectively.

Abstract:The acrid leaf meal form Alocasia macrorrhiza (ALM) contained 244.1 g/kg of protein, 11.9 g/kg of lysine, 4.4 g/kg of methionine, 140.4 g/kg of crude fibre, and 4.92 MJ/kg of metabolizable energy(poultry, AME) on dry matter basis. The acridity of ALM was reduced considerably by treatment with acetone. The acetone-treated ALM(AALM) did not differ significantly from ALM in proximate composition, metabolizable energy and amino acid composition except for acridity. Two 3-week feeding experiments with starter broilers were conducted. Treatment for Experiment 1 consisted of a commercial basal diet (control) and four diets containing basal diet partially replaced by ALM at 40, 60, and by wheat bran at 40 and 60 g/kg respectively. Experiment 2, a control and a test diet supplemented with AALM free of acridity at 40 g/kg were used. The body weight gain of broilers fed ALM diets was reduced significantly against that of control and that of those fed bran diets ( P <0.01 ) because of their lower feed intake, but the performance of the birds fed AALM diet was not depressed ( P >0.05). These results indicated that the utilization of ALM by animals was limited by its acridity, but AALM free of acridity could be used as a feedstuff for animals.

Abstract:研究了水稻白叶枯病单株平均病斑长与病原菌接种前后过氧化物酶活性变化值遗传相关与回归关系，遗传相关系数ｒｇ＝０．８６６。酶活性变化值随病斑长变化的线性回归方程为ｙ∧＝－５１．５１７＋１８．７７８ｘ－０．８７９ｘ２。这表明，感病越强的遗传型，酶活性升高值越大；但高抗病的遗传型，酶活性反而因病原菌侵染而降低。通过病斑长对酶活性变化值作间接选择，相对效率Ｑ＝０．９１０，无助于提高选择效果

Abstract:Nine combinations were obtained by crossing nine mele sterile lines of three types of male sterile cytoplasms Y, CW, WA with their restorer T54, respectively. The differenced of effects of male sterile cytoplasms on F 1 hybrids with homonucleus backround were compared in a randomized bolck experiment. The effects of three types male sterile cytoplasms on the number of panicles, panicle length and grain yield in the F 1 hybrids were significant. The cytoplasms of Y and CW types were superior than that of WA type. But the effects were controlled by the nuclear gentypes and uncleo-cytoplasmic intoraction. Correlation-path anatysis indicated that the number of panicles, seed seting rate and the number of spikelets per panicle had direct influence on the single plant grain yield significantly. For developing strong superior hybrid rice, superior male sterile cytoplasms and the male sterile lines wtih bigger panicle, strong tiller,more number of panicles and high ability of restoration should be selected. The prollems on exploitation of Y type and CW type cytoplasm and the ability of restoration for make sterile lines were also discussed. It suggested that the fertility restoration may be different between the homoplasmus-allonucleus male sterile lines. This is an important prollem to breeding three lines hybrid rice.

Abstract:呼吸代谢的自组织功能表明在，底物自驱动的同化功能，固有的振荡性质，以及呼吸代谢类型对生长发育的调控。提出了呼吸代谢可能起源于Ｃ６－Ｃ３振荡以及遗传密码可能起源于一种推测的“ｔＲＮＡ复合体”的观点。

Abstract:Superoxide dismutase (SOD) activity of leaves of 18 plants growing in South China Agricultural University were determined and reported in this paper. The leaves of 5 plants, Plumeria rubra cv. acutifolia, Magnolia denudata, Passiflora edulis,Bauhinia variegata and Pennisetum purpureum , had higher activity,above 400 units/g fresh weight.SOD was partially purified from Pennisetum purpureum leaves by heat treatment,(NH 4) 2SO 4 precipitation,and DEAE- cellulose chromatography,and its properties studied.

Abstract:The results of this investigation indicated that the stem extract of Eucalyptus urophylla inhibited the rooting rate, root number and the length of roots of mung bean cuttings by 17.09% ,13.47% and 50.21%, respectively; inhibited the rooting rate, root number and the length of roots of pea cuttings by 13.84%,21.37%, and 15.41%, respectively; and inhibited the germination rate of wild cabbage ( Brassica oleracea L. var. caulorapa DC) seeds by 61.42%. The stem extract of airplant kalanchoe ( Kalanchoe pinnata ) improved the root number of mung bean cuttings by 26.26%, but inhibited the length of roots of mung bean cuttings by 32.66%;inhibited the rooting rate, the root number and the length of roots of pea cuttings by 73.59%,59.68%, and 87.83%, respectively; inhibited the germination rates of Indian mustard ( Brassica juncea var. napiformis ) and wild cabbage by 15.30% and 83.43%, respectively. The stem extracts of wanderingjew zebrina ( Zebrina pendula ) and Setcreasea purpurea had also different stimulatory or inhibitory effects on the rooting of cuttings and germination rates of seeds.

Abstract:The production and marketing of pollution-free vegetables were widely investigated and problems existing identified. Guidelines, objectives,criteria and countermeasures for the development of a city providing pollution-free vegetables were proposed, based on the analytic hierarchy process(AHP).

Abstract:Studied the point comparison theorem of solutions for two classes of nonlinear differential equation by establishing differential identity and generalized some known results.

Abstract:阐述了酵母高效表达外源基因的载体系统，转化，转录和翻译，翻译后的蛋白质加工和分泌，对表达外源基因中出现的一些问题及其解决方法作了探讨。