Abstract:Endemism in the Flora of Guangxi is surveyed and analyzed. The result shows thatGuangxi is rich in endemics. 61 Senera of seed plants endemic to China are found in the region, of which 12 are indigenous. The degree of endemism of Guangxi flora is thehishest next to Yunnan which has 15 indigenous endemic genera. The 12 genera endemicto Guangxi are Heteroplexis、Brachiostemvn、Rhaphiocarpus、Buxiphyllum、Gyrogyne、Allostigma、Dayavshania、Dolicholoma、Metabriggsia、Schistolobos、Pseudochirita and Dendrocalamopsis.The flora of Guangxi is also abundant in endemic species amounting to 696 speciesand belonging to 285 genera and 105 families. They tend to be strongly tropical and subtropical in nature, and were likely to originate from the local regions.Endemism developed in the limestone regions of Guangxi shows a remarkable feature. of the 696 endemic species, 230 are exclusively distributed in the limestone regions.This phenomenon is conspicuous,in Gesneriaceae and Sect. Chrysantha Chang ofTheaceac.

Abstract:The Naning Mountain Range, with the location of 24°30' to 26°30'N and 109°to 116° E and covering an area of c. 45000 km2, is situated in the region of boundaries among Fujian, Jiangxi, Guangdong, Hunan, Guangxi and Guizhou Provinces. It is an important dividing zone of natural geography in China and enjoys a relatively rich flora of vascular plants, including 248 families, 1184 genera, 3831 species, 14 subepecies, 348 varieties and 14 forms. The study indicates that the Naming Mountain Range has a typical subtropical flora and is characteristic of floristic transition from tropical to temperate composition. The flora, which possesses lots of relic, archaic, primitive and endemic elements of the Cathaysian flora, must be indigenous to the South China platform. The floras of tropical, subtropical and even temperate Asia might have a common origin as an integrity. The North America might have common floristic origin with the Cathaysia before its complete separation from Europe.

Abstract:The main forest vegetation in Thailand can be roughly divided into two types,evergreen Forest and Deciduous Forest, and seven subtypes, namely Tropical Rain Forest, Hill Evergreen Forest, Semi-evergreen Forest, Coniferous Forest, Mangrove Forest, Dry Dipterocarp Forest and Mixed Deciduous Forest. The geographic distribution, stratified structure and main floristic composition of these types are briefly described.

Abstract:Desmodium intortum (Mill. ) Fawc. et Rendle is a pasture with abundant nutrition and a plant species which Possesses shade tolerance, high nitrogen fixation and is suitable to soil and water conservation. Its root nodules can form in the root system consisting of main root, lateral roots and adventitious roots. Root nodules form soon and in quantity.The effective rate of root nodule is more than 85%. Bacterioid in root nodules is in theshape of club. The somewhat stoloniform stem has many branches and hence will cover larger area. The adventitious root can easily be produced from node or internode. The character of its shade tolerance is related to its thin leaf, less stomata, bigger chloroplasts which contain less starch grains and abundant grana. It grows well in 20% shade condition.

Abstract:The studies on process of differentiation and development of young spike and on morphology of flower and fruit of Melinis minutiflora Beauv. reveal that the process can be divided into nine stages, namely: 1. The stage of first bract primordium formation F 2. The stage of primary branch primordium formation; 3. The stage of secondary and third branches primordia formation ; 4. The stase of spikelet and floret primordia formation ; 5. The stage of stamen and pistil primordia formation ; 6. The stage of pollen mother cell formation ; 7. The stage of meiosis of Pollen mother cell ; 8. The stage of pollen filling; 9. The stage of Pollen maturation. The duration of the process is about 42 days, and the duration from heading to caryopsis maturation takes about 50 days.The inflorescence is a terminal panicle with 2 000-3 000 fertile florets. Each spikelet consists of an outer glume, an inner glume, a lemma of sterile floret and a fertile floret on their rachilla. Each fertile floret includes a lemma, a pelea, a lodicule, three stamens and a pistil. The weight of thousand grains of caryopsis is 91mg.

Abstract:The changes of the protective system against activated oxygen during the enhancement of the chilling resistance induced by the cold hardening and ABA treatment in rice seedlings were studied. The results indicated that in the treated seedlings, activities of SOD and GR of the chloroplast as well as the antioxidant AsA and GSH contents of the leaves increased while the electrolyte leakage decreased. Therefore, its chilling resistance Was enhanced.By using isoelectrofocusing gel electrophoresis analysis, the intensity of three isozyme bands of SOD and the isozyme bands 1, 2, 3 and 6 of GR, except 4, 5, were increased to a different degree in two treated seedlings.After chilling stress, all the activities of SOD, GR and the contens of AsA, GSH were decreased in the treated and untreated seedlings, but the reduction of two enzyme activities and the antioxidant contents in the treated seedlings were less than those of the untreated seedlings.The increase of SOD and GR activities induced by cold hardening and ABA treatment were inhibited by cycloheximide (CHM), at the same time the electrolyte leakage was increased. These results showed that there was a close correlation between the enhacement of chilling resistance and the increase of the protective system ability in the rice seedlings and that the effects of cold hardening and ABA treatment on the Protective system against activated oxygen in rice seedlings were similar.

Abstract:A phosphatase was partially purified from rice leaves by the steps of acidification (to pH 4. 5), ammonium sulfate precipitation, Sephadex G-50 chromatography and DEAESepharose chromatography. ItS Km (PEP) was 0. 1 mmol/L with an optimum pH 5. 3, andwas heat-stable and lossed few activity in the range of pH 4. 0-7. 2. Its activity was potently inhibited by Pi. The enzyme was not specific for its substrate, and could hydrolyzea wide variety of phosphate esters. The results indicated that the enzyme was a non-specificacid phosphatase. Various phosphate ester metabolites exhibited additive inhibition effect on it and was competitive with respect to PEP. The enzyme activity was also inhibited byCu2+, Zn2+, and Fe2+, and unaffected by Mg2+, Mn2+, Ca2+, Co2+, and EDTA.

Abstract:In this paper, endogenous ABA content, growth, Precocious germination, storage protein accumulation of peanut (Arachis hypogaea L. cv. Yueyou-116) embryo in vitro wereexamined. Four treatments in the experiment were given as follows: (A)embryo with seed coat +8% mannitol; (B) embryo with seed coat+no mannitol; (C) embryo withoutseed coat + 8% mannitol; (D) embryo without seed coat + no mannitol. The resultsshowed that the embryo of peanut could normally develop without exogenous hormones.The osmotic regulator such as mannitol inhibited precocious germination, maintained embryonic development and promoted the synthesis and accumulation of storage protein. Endogenous ABA content rose in the treatment with mannitol in vitro. The regulatory effectof mannitol on the development of embryo in vitro was probably related to the incerase ofendogenous ABA content in embryo tissues.

Abstract:The respiration rate of mango (Mangifere indica L.) fruits harvest in summer was 23. Zing CO2. kg-1h-1, the Pulp firmness was>30 p/cm2, and the peel color was deepgreen. The fruits harvested after 8 days, the respiration rate rose up to 132. 9 mg CO2· kg-1 h-1, the pulp firmness fell down to 8-- 9 p/cm2 and the po color cadged toyellowish greene Those harvested after 12-14 days, the peel color became golden yellow, and the respiration rate and Pulp firmness being 39-45mg CO2·kg-1 h-1 and <3 p/cm2, respectively.Experimental results also showed that the contents of soluble sugar, reducing sugar, non-reducing sugar and the soluble-solid in the fruits increased markedly after harvest for 5 days, the peel color changed from deep green to pole green. This might beconsidered as the Physiological turning Point in the pet-harvest period of mango to bethe appropriate harvesting take for prolongjng the storage of the fruits.All sorts of sugar contents decrease and the fruit flavor markedly lost after 14days, indicating that the storage of mango fruits should not be longer than half of amonth after harvest.

Abstract:Different concentrations (0, 0. 2, 0. 5, 1. 0 and 2. 0 mg/L) of 2, 4-D and kinetin (25combinations of them) in the media were studied for inducing embryoSenesis and orpoogenesisfrom young Panicle of rice. When the medium contained both 2, 4-D and kinetin, the plantletswere regenerated via somatic embryogenesis. When the medium contained 2, 4-D only or kinetinonly, plantlets were regenerated via organogenesis but the former was adventitious bud fromorganogenic callus and the later, from the explant directly. In subCulture condition, the mediumcontaining both 2, 4-band kinetin could maintain the culture keeping a high flequency for embryogenesis and the medium with 2, 4--D only, for organogenesis. Frequency of plant regeneration, duration of keeping the capacity for plant regeneration and number of regenerated plant Percallus in embryogenesis wele hiSher, longer and more than those in organogenesis respectively.Embryogenic callus consisted of embryoids, which was made up coleoptile, coleorhiza and scutellum, POSSessed the structure of distinct and POlylayers. The orgnnogenic callus did not aness thisorganletS and friable in structure.