Abstract:Using plant bivalent expression vector pCAMBIA1300 and pBI121 as basic components, a new binary vector harboring tomato chitinase gene Chi3 and tomato β-1,3-glucanase gene Glu-Ac, was constructed through sequential restriction digests and ligations recombination. The two genes driven by CaMV35s promoter were successfully transferred into watermelon cultivars “ZhongYuYiHao” via Agrobacterium-mediated transformation. Successful integration and expression of Chi3 and Glu-A c were confirmed by PCP,Southern blot analysis and RT-PCR. The reaction of detached leaves of transgenic plants to infection Fusarium oxysporum infection was examined. The results indicated that transgenic plants gained certain resistance.

Abstract:In this paper, SMART （switching mechanism at 5＇ end of RNA transcript）was used in the construction of cDNA library of postharvested banana fruit. Total RNA was isolated from banana fruit after harvested for 2 days and cDNA was synthesized by using 15-25 round LD-PCR （Long-distance PCR）. Full length of amplified ds-cDNA （Double-strained complement DNA） was obtained and used in the construction of cDNA library afterward. The capacity of the library was measured to be 5×10⁶ Pfu ml^-1, with 93% recombinant. A cDNA was amplified by using PCR with this library diluted in 96-well-plate as templates. The sequence of this cDNA shows 83% similarity to A ctin2 gene in the NCBI database （Accession No. 692696）.

Abstract:Northern blot was used to analyze the expression ofMAPK3 gene （BPHiw103）, and in situ hybridization technique was developed for localization of MAPK3 mRNA in rice sheath fed by brown planthopper （BPH） after 48 h. The results revealed that the expression of MAPK mRNA was on the whole up-regulated after BPH feeding. In situ hybridization indicated that it was mostly expressed in parenchyma before BPH feeding, while fed by BPH, this gene was mainly increased in phloem, but down-regulated in parenchyma. Such trend was obviously demonstrated in the tissue of inner leaves. All the results showed that the MAPK was induced by BPH feeding, and the gene accumulated in injured rice tissue suggested that it might play the role in the resistant response of rice to BPH feeding.

Abstract:Hydrological conditions, water quality and the distribution of phytoplankton assemblage were surveyed in Tangxi Reservoir, Yaoping County （Guangdong Province）, in 2003, to analyze the effecting factors on seasonal changes in phytoplankton growth. Results demonstrated that phytoplankton abundance in flood season, with the highest in July （〉10⁴ cells ml^-1）, was significantly higher than that in dry season. In January, Bacillariophyta was the dominant alga （63.1%）, while Cyallophyta was less than 20%. In March, May and July, Cyanophyta was the dominant one, with high proportions of 45.6%, 55.9% and 87.7%, respectively, whereas the proportions for Bacillariophyta decreased to 30.1%, 25.9%, and 1.1%, respectively. In November, proportions for Bacillariophyta and Chlorophyta were equivalent, 40% each, and the Cyanophyta composed below 20%. In December, Bacillariophyta made up 25.6% and Cyanophyta 38.2%. In March, May and July, dominant species of Cyanophyta were Microcystis aeruginosa, Pseudoanabaena, and Gloeothece linearis. In dry January, November and December, species of Bacillariophyta were dominated by A chnanthes sp., Melosira ambigua, Melosira granulata and Cyclotella meneghiniana. No close correlation was found between nutrient concentrations in reservoir and seasonal change of phytoplankton community throughout the year. In flood season （from May to July）, obvious variation of dominant species seemed influenced mainly by temporal change of hydrodynamics. Water temperature was positively related to the abundance of Cyanophyta, but negatively to that of Bacillariophyta. It is indicated that water temperature seemed robe the main factor affecting seasonal change ofphytoplankton community in Tangxi reservoir.

Abstract:Floristic composition, areal types of genera, species diversity and main forest types as well as plant forms were investigated in community with rare species Podocarpus neriifolius distributed at Ruoliao Mountain in south-west Zhejiang Province. In the areas studied there were 148 species of vascular plants belonging to 52 families and 95 genera, of which 49 genera were of tropical distribution. The species richness and species diversity of woody plants were obviously higher than those of herbs. Simpson index, Shannon-Wiener index and Pielou＇s eveness index of tree, shrub and herbaceous layers were determined. Species diversity was in descending order in shrub layer, tree layer, and herbaceous layer. According to the habitats, community structure and species composition, the communities with Podocarpus neriifolius can be recognized as three forest types： Castanopsis eyreis - Schima superba forest, Schima superba - Machilus thunbergii forest and Rhododendron simiarurn forest.

Abstract:Two strains of fungal mycelia, SC0351 and SC0652, were obtained from tissue culture of the fruiting bodies of two Polyporus from Basidiomycetes collected at Dinghushan, Guangdong Province, China. From the solid cultures of these fungi, four lanostane-type triterpenes were isolated by using column chromatography. They were identified by spectral analysis as polyporenic acid C （1）, pachymic acid （2）, eburicoic acid （3） and sulphurenic acid （4）. Compound 2 was obtained from Polyporus for the first time.

Abstract:A mixture of five ceramides was isolated from the roots ofSerratula chinensis （Compositae）. The structures of these compounds were elucidated as （2S, 3S, 4R, 8E）-2-amino-8-octadecene-1, 3, 4-triol with five 2-hydroxy fatty acids of varying chain lengths （C₁₆, C_22-25） linked to the amino group （1a-1e, respectively）. Ceramide la was a new compound. The structures were established by spectroscopic and chemical means. The KMnO₄ oxidation method was applied to locate the double bond position in monounsaturated long chain bases.

Abstract:Harvested pear （Pyrus pyrifolia） fruits were dipped in calcium solution to investigate the effects of calcium chloride solution treatment on the content of pectin, the contents of different soluble calcium, the changes in activities ofpectinesterase （PME） and polygalacturonase （PG） and on the fruit firmness. The results showed that calcium solution treatment significantly increased total calcium content in fruits, improved fruit firmness and maintained permeability of cell membrane significantly. The content of NaCl soluble calcium was highest in treated fruits, followed by water-soluble calcium, calcium acerate and HCl-soluble calcium. An increasee in water-soluble calcium was observed on the 21 st day in treated fruits, while NaCl soluble calcium decreased. The contents of water-, NaCl- and HCl-soluble calcium increased significantly after calcium treatment except for acetic acid soluble calcium. Calcium treatment delayed degradation process of pectin and inhibited PG activity, but had no obviously inhibitory effect on PME activity. Effect of calcium treatment on fruit firmness was probably related with the inhibitory effect of PG activity.

Abstract:One-year-old seedlings of four woody dominant species of different succession stages from south subtropical forest were potted under 100% and 32% of natural light for six months. Light response curve of photosynthesis and some parameters of chlorophyll fluorescence in these species were determined. Under 100% of natural light, Pinus massoniana had highest values of maximum photosynthetic rate （Pmax）, light saturation point （LSP）, light compensation point （ LCP）, dark respiration rate （Rd）, the apparent quantum yield （AQY）, leaf total electron flow rate （JF） and photochemical fluorescence quenching （qP）, whereas Cryptocarya concinna exhibited maximum fractions of total electron flow partitioned to photorespiration （JO/JF）. AQY under 100% of natural light was in the order of Pinus massoniana 〉 Castanopsis fissa 〉 Schima superba 〉 Cryptocarya concinna, while the result was the reverse under 32% of natural light. These suggest that Pinus massoniana, the pioneer species at early succession stage of forest community, is the plant species adapted to high light intensity, while Cryptocarya concinna, a species at succession climax stage has an advantage in light utility under low light environment. The results also support that the increasing ratio of total electron flow allocation to photorespiration in Cryptocarya concinna is one of the strategies to protect itself against high light damage.

Abstract:The spores of Blechnum orientale L. were cultured in mixed soil. The spore germination and the gametophytic development were observed under microscope. The spores are dark-brown, monolete, bean-shaped in equatorial view and elliptical in polar view. The spores germinate about one week after sowing. The germination is of Vittaria type and the gametophyte development is of Aspidium type. Prothallial plates begin to form when the filaments develop up to 5-10 cells, The young prothalli are developed in two weeks after sowing. Mature prothalli are cordate-shaped. Profuse unicellular hairs occur on the surface and margin of the prothalli. The archegonia form in one month after sowing. The archegonial neck is usually composed of four rows of cells and 3- 5 cell layers high when matured. The antheridia appear about 10 days earlier than archegonia. Antheridia are shaped like pellets consisting of three cells. Young embryos can be observed from prothalli about 2 weeks after fecundation.

Abstract:The karyotypes of four Cymbidium sinense cultivars were studied. Somatic chromosome numbers of cultivars ‘Qijianheimo＇ and ‘Qijianbaimo＇ are 2n=40 （diploid）, the karyotype formulas being 2n=2x=40=30m＋10sm and 2n=2x=40=2M＋36m＋2st, respectively. However, the chromosome number of cultivars ‘Jinzui＇ and ‘Yinbian＇ are 2n=41 and are aneuploid. The chromosome structures of all the four cultivars mainly consist of metacentric chromosomes. According to Stebbins＇ classification of karyotypic asymmetry, the karyotype of cv. ‘Yinbian＇ is of 1B type, and that the other three of 2B type.

Abstract:The chromosome numbers of 3 monotypic genera in Sapindaceae are reported. The chromosome numbers were determined to be 2n=40 for Hondeliodendron Rehd., 2n=28 for Delavaya Franch., and 2n=26 for Eurycorymbus Hand.-Mazz.. All the chromosomes of the three genera are small in size. Chromosome numbers of Handeliodendron Rehd. and Delavaya Franch. are reported for the first time.

Abstract:One hundred of morphological characters of 69 species （representing 52 genera and all tribes and subtribes of the subfamily Chloridoideae of Gramineae） are used to reconstruct the phylogeny for the Chloridoideae. Cladistic analysis show that the monophyly of Chloridoideae and its origination from danthonoid group are supported. Five clades are found in correlation with traditional classification systems. Clade A comprises 2 genera of Pappophoreae, clade B 5 genera of Eragrostideae, clade C 6 genera of Eragrostideae, clade D 9 genera of Eragrostideae, and clade E comprises 8 genera of Eragrostideae, 9 genera of Chlorideae, and 1 genus of Leptureae. The two largest tribes Eragrostideae and Chlorideae turn out to be polyphyletic. The Chlorideae affinity of Leptureae is substantiated in the cladistic study. The basal tribe Pappophoreae may provide a link between the chloridoids and the danthonoids. A pattern of segregation of species from Old World to New World is evident in several clades. These results provide a framework for further studies at the supra-generic levels moving toward to a comprehensive systematic treatment of the Chloridoideae.

Abstract:Merremia boisiana （Gagnep.） V. Ooststr. （Convolvulaceae） is an invasive plant that newly appeared in a forest plantation near Guangzhou. The photosynthesis characteristic observed by using chlorophyll fluorescence technique in this plant was examined under different actinic lights, and the light utilization was measured in detached leaves under different stress of low or high temperatures and dehydration. The results showed that the chlorophyll fluorescence parameters Fv＇/Fm＇, qP and ΦPSⅡ decreased with the increase of actinic light intensity, but qN and NPQ increased. When detached leaves were treated for 6 hours at 5 ℃, the Fv＇/Fm＇, qP and ΦPSⅡ were higher than those at 25℃ and 45℃. However, if detached leaves were treated for 6 hours at 5℃ and 45℃, the NPQ was evidently lower than those at 25℃ （control）, and the qN reduced a little. Being dehydrated for 12 hours, the detached leaves still had certain ability of light energy conversion. Whereas the values of qP, ΦPSⅡ, qN and NPQ were significantly decreased after the leaves were dehydrated for 24 and 36 hours. It is shown that Merremia boisiana has strong adaptability to different light intensity, temperature and water conditions, which may be an important cause of its rapid dispersal in forests.

Abstract:Interspecific F1 hybrid between Cymbidium ertsifolium ‘Xiao Tao Hong＇ and C. aloifolium （L.） Sw. were obtained by pollination. The fresh weight of fruits of F₁ hybrid was higher than that of selfed C. ensifolium ‘Xiao Tao Hong＇ , but seeds of the former were less than the latter. Green protocom-like bodies appeared after 90 days, from hybrid embryos cultured on MS medium supplemented with 170 mg L^-1KH₂PO₄, 1 mg L^-1 BA and 50 g L^-1 banana, and formed a number ofplantlets after 210 days. However, only a few rhizomes occurred from seeds of selfed ‘ Xiao Tao Hong＇ cultured after 210 days. Embryo culture of the hybrid had the advantage of fast growth and high plantlet formation rate.

Abstract:The name Osmanthus marginatus var. pachyphyllus which was published based on Osmanthus pachyphyllus H. T. Chang is invalid because two type specimens （one in flower, one fruiting） were indicated in the protolog. The name is here validated at the rank of variety, with the fruiting specimen designated as the holotype.

Abstract:The leaves and stems of Labiatae plants are generally covered with abundant glandular hairs which can secrete essential oil. This paper reviews the recent researches on the glandular hairs and secretion in Labiatae. The types, morphological structures, and the development of glandular hairs, as well as the secretion are discussed.