Abstract:The present study is aimed to develop an effective method for the detection of Liberobacter asiaticum that causes citrus Huanglongbing disease. It was shown that the DNA of the pathogen could be amplified by polymerase chain reaction (PCR) in vitro and the appearance of such DNA was significantly detected in the samples of infected citrus trees of the various cultivars. To use PCR for the detection of the infected trees without any symptom yet at the early stage of the infection. This technique can be effectively applied to screen disease free seedlings, establish disease free citrus nurseries, and control the spread of the diseased seedlings.

Abstract:建立了聚合酶链反应（ＰＣＲ）扩增技术检测香蕉组织和单头蚜虫内的香蕉束顶病毒（ＢＢＴＶ），并报道了ＢＢＴＶ免疫捕捉ＰＣＲ（ＩＣ－ＰＣＲ）和直接结合ＰＣＲ（ＤＢ－ＰＣＲ）检测方法，ＩＣ－ＰＣＲ和ＤＢ－ＰＣＲ分别能从４μｇ和０．４ｍｇ香蕉叶组织中检测到ＢＢＴＶ。

Abstract:通过一系列的细菌学性状的致病性试验，鉴定出广东省水稻一种新病害－水稻细菌性基腐病的病原为菊欧氏杆菌玉米致病变种Ｅｒｗｉｎｉａ ｃｈｙｓａｎｔｈｅｍｉ ｐｖ．ｚｅａｅ，并对该病原菌的生物学特性进行了进一步的研究。结果表明：病菌生长的最低温度为１２℃，适宜温度范围２８￣３６℃，其中以３２℃最适，最高温度４１℃，致死温度５３℃、１０ｍｉｎ。该病菌生长的ｐＨ值范围为ｐＨ５￣１１，其中ｐＨ７最适宜。

Abstract:From the view point of coevolution of Papilio xuthus L. (Lepidoptera:Papilionidae) and its hosts, and based upon the feeding behavior and digestive characteristics, three artificial diets were developed in the rearing program of thrarthropod. Evaluation of the pupal weight showed that diet No.3 was the best for rearing Paplio xuthus L. for four generations: mean pupal weight of larvae feeding on the diet was significantly higher than those feeding on citrus leaves in each generation, and the larval survival rate was significantly higher on diet No.1 and diet No.2.

Abstract:Forty varieties of asparagus bean Vigna unquiculata W.ssp. sesquipedalis (L.) Verd were studied in three years in vegetable farm in the University, to test the effects of varieties of asparagus bean on the population of Maruca testulalis Geyer. The results in the experiments showed that the densities of the larvae of the insect pest in the flowers and in the beans were different significantly between the varieties of the bean. The larval densities of variety Xinqing were 18, 17.3 and 6.33 larvae in 30 flowers of the bean in 1988, 1989 and 1990 respectively, and lower than other varieties. It was found that the larval population between the stages in flowers and in beans showed a positive regression corelationship.

Abstract:根据小鼠肌肉的６－磷酸葡萄糖脱氢酶（Ｇ６ＰＤ）的ｃＤＮＡ序列设计并合成内外２对引物，以巢式ＲＴ－ＰＣＲ方法检测昆明小鼠１－，２－，４－，８－细胞期早期胚盈是否转录出Ｇ６ＰＤ的ｍＲＮＡ，结果发现１￣８－细胞期早期胚胎的ｍＲＮＡ均能以外引物扩增产物为模板通过内引物扩增出一条３７８ｂｐ特异性条带。表明昆明小鼠１￣８－细胞期早期胚胎的Ｇ６ＰＤ基因已表达，磷酸戊糖途径已是其代谢葡萄糖的主要方式之一。

Abstract:将２８８只ＡＡ鸡分成４组，分别置于２５．１０，２９．９８，３３．０８和３６．９２℃的温控室内，研究不同高温环境对肉鸡生产性能，腿肌水分，蛋白质和脂肪含量及血浆甲状腺激素，胰岛素水平的影响。结果表明：高温极显著减少肉鸡体增重和采食量（Ｐ〈０．０１），提高饲料转化睾（Ｐ〈０．０１），高温有降低腿肌中蛋白质含量和提高脂肪含量的趋势。不同高温条件下，各试验组与对照组相比，血浆Ｔ３浓度升先高后降低，Ｔ４浓度

Abstract:菌毛提取液，荚膜多糖－破伤风类毒素（ＣＰＳ－ＴＴ）载体抗原液及热、甲醛和超声波灭活菌液中加入蜂胶佐剂，制成菌苗免疫石岐杂鸡，７７及１１２ｄ攻毒保护试验结果表明，超声波灭活菌体的免疫原性最好，热灭活菌体最差，菌毛，ＣＰＳ－ＴＴ及甲醛灭活菌体的免疫原性相当。尤其采用超声波处理的菌液作抗原为明显。

Abstract:In this study, large numbers of mast cells were found in the thymus of goose under transmission electron microscope. They were located mainly in the medulla of the thymus, were round or ellipsoid in shape, had a few cytoplasmic processes, and possessed a rounded, elliptic, or crescent shaped nucleus with distinct nucleoli. Their cytoplasm contained abundant organelles and numerous membrane bound secretory granules that were mostly round in shape and varied in size. According to the ultrastructural features, these granules were classified into 4 types: type 1 granules contained electron dense fine granular material; type 2 granules contained electron dense coarse granular material; type 3 granules contained electron dense concentric beaded chains; type 4 granules showed almost homogeneous high electron density. No crystalline, scrolled or lamellar structures were evident in the granules.

Abstract:It had evaluated tolerance of serveral sugarcane genotypes to low or no phosphorus supply, according to relative changes of biomass,by addition of nutrient solution with different level of phosphate( 1.0, 0.2,0.1,0.0 mMol/L in Hoagland solution) to sandy culture in pot trial;meanwhile,the changes of photosynthesis ability,inorganic phosphate concentration and acid phosphatase activity in leaves were also determined.The results showed that among those genotypes yuetang 57-423 and Badila have low tolerance to low or no phosphorus supply;yuetang 71-210,yuetang 85-177,yuetang 81-3254, guitang 1 have the highest tolerance; while yuetang 79-177,yuetang 63-237,taitang 172,new taitang 10 are moderate;taitang 134 could just adapted to low phosphorus condition.The net photosynthesis rate of unit leaf area didn't change significantly in most case but increase in some case and the total yield of photosynthsis of per leaf decreased with decreasing of phosphate supply,the later is not true in low-phosphorus-tolerating genotypies(i.e yuetang 71-210,yuetang 85-177).The concentration of inorganic phosphate is in steady-state,and activity of acid phosphatase enhanced with decreasing phosphate supply.

Abstract:采用细胞悬浮培养的方法，以烟草红花大金元细胞为材料，研究了几种有机营养物质辅酶Ｑ１０（Ｃｏ１０）合成前体物质及Ｃｏ＾６０－γ射线对烟草悬浮培养细胞生长和辅酶Ｑ１０形成的影响。实验证明，肌醇，酵母膏，盐酸硫胺素对烟草悬浮培养生长和ＣｏＱ１０含量都有一定的影响。

Abstract:Common bean genotypes were studied for their leaf anatomic response to low P in the hydroponic experiments. The results indicated that P deficiency decreased P uptake and inhibited the growth of plants. Under low phosphorus conditions, the middle-leaf thickness, thickness of palisade tissue and spongy tissue(except DOR 60), cell number of palisade tissue also increased, while most cell and vacuole areas decreased. There was genotypic variation in response to low P. The P efficient large-seeded genotypes tended to have more cell numbers per tissue area but smaller cell area per cell.

Abstract:Kernels from 11 representative high quality early indica rice varieties cultivars in south china were analysed for protein contents and amino acid compositions prior and after storage under atmospheric temperature. The protein nutrient qualities of 11 indica rice varieties were evaluated by comparing with FAO/WHO and egg protein mode, and calculating the chemical scores of 8 essential amino acids. The results showed that protein content and amino acid composition and content were relatively stable, showing basically no change with the duration of storage. Protein content averaged at 10.23%, ranging from 8.80% to 13.10% with a variance coefficient 10.80%. Difference among cultivars was great. Contents of the 8 essential amino acids were significantly different among cultivars, Alternation ranges and variance coefficients of the absolute contents of the 8 essential amino acids were greater than those of their relative contents. The quality of protein also displayed significant difference among cultivars. There was a tendency that total essential amino acid content decreased with the increase of protein content. Attention should be paid on increasing the rates and contents of the essential amino acids in the proteins of rice kernels through genetic breeding.

Abstract:Germinating seeds of three rice varieties (a high quality HuaXianZhan, a hybrid YueYouQingZhan and a common SuiLingZhan ) were treated with acetochlor at different concentrations. The growth of rice seedling was differently inhibited. HuaXianZhan was the most sensitive variety, SuiLingZhan the most resistant and YueYouQingZhan the intermediate. There was a respiratory peak found on 4-6 days after germination for all the three varieties. For sensitive variety, acetochlor showed a heavy inhibition to respiratory rate, especially, to respiratory peak, which was strengthened by EMP and PP pathways, and eventually, the seedling growth was inhibited greatly. However, the resistant one was affected only slightly in both respiratory rate and respiratory peak, therefore, its seedling growth was subjected to just a little inhibition.We concluded that these could be one elementary physiologcial cause for the growth inhibition of sensitive rice seedlins by acetochlor.

Abstract:The leaf characteristics of hybrid corn (yuedin 9) for different planting densities were tested in the experimental farm of South China Agricultural University in Guangzhou China in the spring of 1996. The corn yield characteristics were better in the density of 45 thousand plants per hectare than in the density of 67 5 thousand plants, but that was not reach a singificant level. The total leaf age of the tested hybrid corn was 19.1 and also was a rather stable character. The relationship between the leaf area and the dry matter inerement showed index cure. The plants of low density, population had higher assimilation rate in the late growing stage. The long wide rate of leaf showed parabola cure. The longest and widest leaf was 12th leaf and 13th leaf, which were unfolded at the young panicle differentiation stage. Every other leaf appeared in 3 days and unfolded in 2 days in the middle and late growth period, but senecensed in 5 to 10 days. The function days of leaves would extend with leaf arrangement.

Abstract:ＳＯ２处理结合低温贮藏，显著降低了龙眼果实的呼吸强度和果皮ＰＰＯ（多酚氧化酶）活性，出库后，仍能维持这种抑制效果，从而抑制了果皮褐变，改善了果实外观，延长了货架寿命。

Abstract:The classification and nomenclature system as well as the method and procedure for red soil resources (RSR) classification were proposed based on the evaluation of the aims and principles of RSR classification . Zhejiang province was selected as an example to carry out RSR classification based on geographic information system (GIS). The RSR of the whole province were classified 84 types, and the area distribution of each RSR type was calculated with foxpro database.

Abstract:This paper reports the setting up of a series of evaluation indices for degraded agroecosystem which include monotonous index, non equilibrium index, non stability index, non sustainable index, production resistance index, soil nutrient degradation index, dull index and self contained index. The assessment of agroecosystem degradation was conducted by using these indices in Zigui County of the Three Gorges Reservoir Area.

Abstract:过去有关特有现象的研究主要限于定性的分析，可比性和精确性较差。该文尝试引入特有现象的定量化指标，以推动特有现象的分析研究从定性水平向定量水平迈进。所引入的４种定量化指标分别是：特有水平，特有系数，特有度以及特有综合指标。

Abstract:Floristic characteristics of the seed plants of Nanling National Nature Reserve were studied. A total of 2 292 species and varieties of the seed plants belonging to 822 genera, 175 families, was identified in Nanling National Nature Reserve. Among them, there are 30 species belonging to 20 genera, 9 families are of gymnosperm and 2 262 species and varieties belonging to 802 genera, 166 families are of angiosperm. The distribution elements of Nanling's flora are complex, diverse and widely related to many parts of the world. They comprise 14 of 15 distribution types of Chinese seed plants.The flora is predominated by tropical and subtropical elements and also strongly affected by temperate elements. There are 33 endemic genera. Nanling's flora has a long biological history. On the one hand, there are many primitive and relic plants, Nanling might be one of their original centers;on the other hand there are also many advanced plants, Nanling might be one of their specialization and distribution centers.

Abstract:以不同浓度苏芸金杆菌伴孢晶体接种于４龄起蚕，观察研究家蚕细胞性中毒病的急性和慢性中毒症状及中肠组织细胞的病理变化过程及发病规律。蚕儿食下伴孢晶体６．５×１０＾－９ｗｈ ／Ｌ／Ｌ后，呈慢性中毒，可发现中肠细胞有明显的防御反应，部分蚕最终可修复受损中肠细胞导并使蚕儿恢复正常。

Abstract:The principal component analysis method was used to analyse the aroma constituents of 7 high aroma pattern Oolong teas The results showed that each aroma pattern of the Oolong tea has its own importing aromatic material The aroma charasteristic was different when the aroma composing matter changed The aroma constituents expression patterns were listed for Rouguixiang tea, Yulanxiang tea, Huangzhixiang tea and Zhilanxiang tea

Abstract:利用紧Ｈａｕｓｄｏｒｆｆ空间Ｘ中闭无处稠子集与连续函数空间Ｃ（Ｘ）中单调网之间的对应关系，得到正规测度的一个特征；定理 设Ｘ是紧Ｈａｕｓｄｏｒｆｆ空间，则０≤μ∈Ｍ（Ｘ）是正规的当且仅当对Ｘ中的每一闭无处稠子集Ｇ，有μ（Ｇ）＝０。

Abstract:大力推行三高农业的同时，人们越来越认识到农业持续发展不仅仅是三高问题，而且和环境、资源充分利用等息息相关（赵其国，１９９７）然而在高投入和高产出情况下，由于大量使用化肥造成地下水硝酸盐污染和蔬菜累积硝酸盐（沈明球等，１９８２；周根娣等，１９８９），...

Abstract:N2O既有破坏臭氧层的作用,也是大气中主要温室气体之一.在农业生产上,人们向土壤中施入的氮肥,除部分被植物吸收利用外,其余部分以硝化和反硝化作用产生的N2O 和N2等方式释放到大气中,参与温室效应作用.本试验对广州地区农业生产上常用的2种有机肥料对稻田的N2O排放量的影响进行了研究,旨在阐明在生产实际中,在保证正常生产的情况下,如何采取有效的方法控制稻田N2O排放量,这对环境保护具有现实意义.

Abstract:食品中细菌总数是食品卫生的微生物学指标之一随着经济改革和对外开放，越来越多的食品生产和出口如何能更准确快速的检测食品中细菌总数是食品卫生部门面临的一个突出问题目前细菌总数检测中我国国家标准是应用营养琼脂（中华人民共和国卫生部，１９９４），美国等...