Abstract:The developmental process of root in Polygala tenuifolia Willd. was studied by anatomical methods, and the structures of the one-year-old and two-year-old main roots were compared. Meanwhile, the main medical composition and storage nutrition of the root was localizated by histochemistry. Polygala tenuifolia is taproot system, which is medicinal portion. The development of the root underwent four stages: promeristem, primary meristem, primary structure and secondary growth. The apical promeristem was originated from radicle and consisted of three initial groups, and they prossessed the typical cytological characteristics of meristem. The primary meristem consisted of calyptrogen, primordial epidermis, periblem and plerome, while the primary structure consisted of epidermid, cortex and central cylinder. Primary xylem is diarch. The secondary growth mainly depended the activity of the vascular cambium and cork cambium. Secondary xylem composed of large vessels, wood fibres and little xylem rays. A lot of phloem parenchyma cells, a small amount of sieve tubes and companion cells built up secondary phloem. The vascular has one or three flats cells. The cork cambium originated from the pericyclic cells and created multi layer of phelloderm parenchyma cells. The infrastructures were identical 0between one-year-old main root and two-year-old main root, but phelloderm cells are more than ten layers in two-year-old main root. The reserve substance was mainly oils and little polysaccharides in Polygala tenuifolia root. The tenuifolic saponins existed in all parenchyma cells. Xanthones accumulated in the cork cambium, phelloderm parenchyma cells and secondary phloem.

Abstract:Petiolar structure of 26 Osmanthus species was observed under light microscope. The results showed that there were rich variations among petiolar anatomical characters of Osmanthus. There are 3 types of cross section of petioles (U, V and Y types), the outmargin shapes of petioles are undulated, sinuolate or nearly smooth. Trichomes are present or not. In most species, there are 3 vascular bundles (one bigger and two smaller) in cross section of petioles. There are abundant variations on outline of vascular bundle among species. The vascular bundle types in cross section of petioles are amphicribral bundle, almost amphicribral bundle and collateral bundle. There is a pith cavity on center of vascular bundle in O. minor, O. matsumuranus, O. marginatus and O. americanus. Some species have sclerotic cell or stone cell. The anatomical characters of petioles could be used to circumscribe the species within Osmanthus as they are stable between different species.

Abstract:A new species of Syzygium Gaertner (Myrtaceae), S. impressum N. H. Xia, Y. F. Deng & K. L. Yip, is described and illustrated. The new species is similar to S. buxifolium Hook. & Arn., but differs by its obovate leaves, conspicuously impressed midveins, and smaller fruit.

Abstract:The features of seed plant flora in Chongqing City, China, are as follows: (1) wild plants are diverse in species (208 families, 1127 genera and 4764 species), and the floristic elements are copious, including 12 distribution types and 13 varieties in the families and 15 distribution types and 23 varieties in the genera. (2) The tropical taxa are predominant with 83 tropical families (39.90%) and 454 tropical genera (40.28%), indicating that Chongqing flora is relative to tropical one. (3) Although the endemic families and genera are scarce in Chongqing, the endemic species are rich.

Abstract:Based on field investigation and literature consultation, seventy three species of alien invasive plants belonging to 59 genera of 27 families were identified in Guangzhou. Of them, nineteen alien invasive species belonging to Asteraceae, eight to Poaceae, and seven to Fabaceae and Amaranthaceae respectively, and they take up 56.2% of the total number of the invasive plants in Guangzhou. With respect to the life form of alien invasive plants distributed in Guangzhou, the most dominant plant are terrestrial herbs (58 species), then shrubs (10 species), aquatic herbs (3 species) and trees (2 species), which distributed in the area of heavily disturbed and low altitude. In addition, based on the growing, dispersal status and other ecological features of the invasive plants in the field, eleven alien invasive species were evaluated to be at the highest degree of threat to the local biodiversity, twenty five at the medium, and 37 at the lowest. Constitutional analysis of the original locality of the alien invasive species revealed that 61 species were from tropical America and took up 83.6% of the total species in Guangzhou. Comparing with other domestic regions in terms of the number of the alien invasive plants, Guangzhou and Guangxi share the most and have 62 species. However, concerning the species that have caused serious threat to local biodiversity, Guangzhou shared eight species with Hong Kong, seven species with Shenzhen, and six species with Guangxi. Moreover, we also evaluated the potential threat for those alien plants that grow in Guangzhou and have caused serious biodiversity damages in other domestic regions. Our result reveals that the government should pay much attention to monitoring these invasive species so as to prevent them from dispersing and causing ecology disaster in Guangzhou. Furthermore, the invasive pathways and preventive strategies of alien plants are also summarized here.

Abstract:In order to understand the modern pteridoflora of Guangzhou, Guangdong Province, we briefly reviewed the recorded pteridophytes in history and made extensive explorations in this area in the last two and a half years. As a result, 176 species belonging to 82 genera in 37 families are now recorded for Guangzhou. Three species, Dicranopteris gigantea, Hymenophyllum spinosum, and Dryopteris gymnosora, are newly recorded from Guangdong. The five species-rich families are Thelypteridaceae, Dryopteridaceae, Polypodiaceae, Athyriaceae and Pteridaceae. The geographical distribution of the species shows that this flora mainly consists of tropical & subtropical Asian and eastern Asian elements but lacks local endemics. About 80% of the species of this flora grow in humid habitats of dense forest, about 20% occur in relatively dry habitats such as sparse forest and shrub in roadsides, and two species are hydrophytic. Regarding the horizontal distribution in Guangzhou, only a very small proportion of the species occurs in the southern and central areas, but about 90% grow in the montane area of Conghua in northeastern Guangzhou, from which 74 species only occur in Conghua. Within Guangzhou, the abundance of the 176 species can be classified in four groups, i.e., 33 species are Cop (copiosae)2, 48 are Cop1, 53 are Sp (sparsal) and 41 are Sol (solitariae). Fifteen species, i.e., Phlegmariurus austrosinicus, Angiopteris fokiensis, Hymenophyllum spinosum, Alsophila denticulata, A. metteniana, A. podophylla, A. spinulosa, Ceratopteris thalictroides, Diplazium tomitaroanum, Dictyocline mingchegensis, Metathelypteris adscendens, Leptogramma scallanii, Brainea insignis, Woodwardia prolifera and Arachniodes nigrospinosa, are evaluated as rare and endangered in Guangzhou but not under any effective protection at present.

Abstract:Ten compounds were isolated from the 95% ethanol extract of the twigs of Garuga forrestii. On the basis of the spectral data, they were characterized to be 13α,14β,17α-lanosta-7,24-diene-1β,3β-diol (1), stigmasta-5-ene-3β,7α-diol (2), stigmasta-5-ene-3β,7β-diol (3), stigamastane-3β,6α-diol (4), β-sitosterol (5), catechin (6), (Z)-ferulic acid tetracosyl ester (7), (E)-ferulic acid tetracosyl ester (8), 4-hydroxybenzoic-3-methoxy acid (9), and 4-methoxyindane (10). All compounds were isolated from this species for the first time.

Abstract:Ten compounds were isolated from the leaves of Microcos paniculata L. On the basis of spectral data, they were identified as friedelin (1), arjunglucosideⅡ (2), kaempferol-3-O-β-D-[3,6-di-(p-hydroxycinnamoyl)]-glucopyranoside (3), kaempferol-3-O-b-D- glucopyranoside (4), isorhamnetin-3-O-β-D-glucopyranoside (5), narcissin (6), vitexin (7), violanthin (8), isoviolanthin (9) and isovitexin (10). All these compounds were obtained from this plant for the first time.

Abstract:Seven compounds were isolated from the cultures of Geotrichum candidum. On the basis of their spectral data, they were identified as leucine (1), uracil (2), thymine (3), pyrocatechuic acid (4), p-hydroxybenzoic acid (5), 3,5-dihydroxybenzoic acid (6), and 7,8-dimethylalloxazine (7). All compounds are isolated from this fungus for the first time.

Abstract:Seventeen phenotypic traits were investigated in 226 individuals of 11 natural populations of Cerasus campanulata from Fujian，Jiangxi and Guangdong, China, using coefficients of variation，F-test of One-way variance analysis，correlation analysis and clustering analysis．The variation was much greater within populations than among populations, which suggested that little differentiation occurred among populations．Among 17 phenotypic traits, flower color, the number of flowers per plant were significantly correlated to both longitude and latitude，petal width to both longitude and altitude，flower color，the number of flowers per plant to annual rainfall，the number of flowers per plant，petal width，flowering habit to hours of sunshine，and petal width to both annual mean temperature and the frost-free period．There was significant relationship between geographic distances and Mahalanobis distances calculated from all phenotypic traits．

Abstract:Seedling recruitment has important influences on population stability and community succession. Cupressus funebris forest，a secondary community widely distributed in the Three Gorges area, China, plays an important role in environmental protection. Effects of soil and light on seed germination, seedling survival and seedling growth were investigated in C. funebris to elucidate the pattern of seedling recruitment in the Three Gorges area. Seeds began to germinate 20-30 days after seedling, and the germination peak appeared 35-45 days after seeds were seeded. The average germination percentage was 47.7%. Soil substrate had significant effects on seed germination. However, the effect of light on seed germination was not significant. The average mortality rate was 52.6% in seedlings. Both the soil type and light remarkably influenced seedling survival. The lowest mortality occurred in seedlings on forest soil and under 80% light condition. The stem growth of C. funebris seedling showed an “S” pattern, whereas leaves augment was in a linear pattern. The seedling growth and biomass accumulation were affected significantly by light. Seedling biomass increased with light intensity. The biomass allocation of C. funebris seedling was also analyzed to elucidate the relationship among different seedling parts.

Abstract:Flowering habit, pollen fertility, rate of seed setting of natural population of common wild rice was investigated in Danzhou, China. Its flowering period was approximately 2 months long (from early October to early December). In sunny days, flowers opened mainly during 11:30 am to 11:50 am, with the optimum temperature of 29.84±2.27℃ and the relative humidity of 53.33±6.63％. In cloudy days, flowering was delayed 20-30 min. It took 70 to 100 min for each floret from opening to closing including opening stage of 10 to 20 sec, pollen scattering after 50 to 60 sec and closing stage of 1 h. Flowering time was negatively related to wind speed and positively related to temperature. Most individuals had a fertility rate of over 50％ and seed setting rate of less than 10％. Flowering habit of natural population of common wild rice has the difference with common rice in Danzhou .The Strategy of reasonably to utilize and effectly to protect natural population of common wild rice is proposed.

Abstract:Asymbictic germination of an endangered orchid, Renanthera imschootiana Rolfe was achieved through sowing the seeds after pollinating for 145 d on different mediums axenically. In 30 d after sowing, the seed germination rate reached 93.1% on the 1/4MS medium supplemented with 20% （v/v） coconut milk（CM）, 1 g L-1 peptone and 10 g L-1 sucrose. After 75 d, on the VW medium with 10% CM, 36.6% of the seed formed plantlets. The content and concentration of multi-salt of basic medium has a positive (or great) effect on seed germination and plantlet growing. 1 g L-1 peptone increased seed germination rate, while 150 g L-1 apple homogenate can enhance plantlet growth. Seed germination rate was found no significant difference when seeds were sowed in light or dark, but 3-weeks culture in dark had a negtive effect on developing seedlings after seed germination. More than 95% seedlings were survival after transplanted to the g

Abstract:The genomic DNA was extracted from Castanopsis hystrix A. DC. using the modified method of CTAB, and the optimization of its RAPD reaction system was also studied. Results showed that the high-quality genomic DNA can be obtained with the modified method of CTAB, and it could be directly used for RAPD analyses. The optimal PCR system for RAPD analysis was as follows: 0.8 ng μl-1 DNA template, 2.0 mmol/L Mg2+, 0.8 U Taq polymerase, 0.35 mmol/L dNTPs, 0.28 μmol/L random primer, in 25 μl reaction system. RAPD program is 3 minutes at 94℃ for predenaturation, then followed by 35 cycles, each with 30 seconds at 94℃ for denaturation, 1minute at 39℃ for annealing , 2 minutes at 72℃ for extension, finally extension at 72℃ for 10 minutes.