Abstract:The Yarlung Zangbo River Basin, located in Qinghai-Tibet Plateau, is an important region of the World biological diversity and ecological landscape protection, which fragile environment is significantly affected by global warming. In order to understand the spatial-temporal difference of vegetation coverage in Yarlung Zangbo River Basin response to climate change, the correlation between vegetation coverage and climatic factors in 2002-2014 was analyzed by center of gravity model. The results showed that there was a positive relation in migratory direction of gravity center between vegetation NDVI and interannual precipitation. The monthly NDVI of vegetation was mostly affected by precipitation of 0-1 month before. There was also a time-lag effect between seasonal NDVI of vegetation and precipitation, and there was a positive relation between NDVI of vegetation in spring and winter and precipitation of prior season. Meanwhile, the time-lag effect of trees and shrubs on precipitation was bigger that of herbs. The vegetation growth had relation with the temperature change in growing season. Correlation coefficients between month mean temperature and NDVI of vegetation reached up to the maximum value had significant differences. The spatial and temporal heterogeneity between NDVI of vegetation and climatic factors is of great ecological significance for the protection of eco-environment in Yarlung Zangbo River Basin.

Abstract:In order to select excellent clones of Eucalyptus urophylla, the growth and leaf characters of 20 clones in half-year-old under water and nutrient stresses were analyzed and evaluated by using a randomized complete block design according two factors and three levels. The results showed that leaf apex angle (LBA), leaf length (LL), leaf width (LW), leaf perimeter (LP) and leaf area (LA) had significant differences among water and nutrient treatments, indicated that water and nutrient had influence on the leaf size. There were significant positive correlations between most of growth and leaf characters, and a few showed significantly negative correlations. The principal components analysis showed that the cumulative contribution rate of the first four principal components accounted for 98%, indicating that they had strong representativeness. Growth traits under water, nutrient, water×nutrient interaction reached a significant level except for ground diameter (GD) under water × nutrient interaction. The component variance for H, GD and CW ranged from 2.19 to 149.59, and repeatability ranged from 0.16 to 0.45. The four excellent clones, such as LDUA10, ZQUA9, ZQUA8 and LDUA24, were selected according to 20% selected ratio and genotypic value, and the H, GD and CW of four clones was 5.0%, 12.8% and 14.5% higher than control, which would provide basis for further selection and extension of superior clones.

Abstract:In order to understand the regeneration mechanism of Fagus lucida forest in Kuankuoshui Nature Reserve, Guizhou, the effect of Chimonobambusa utilis on population structure of F. lucida was studied by quadrat method. The results showed that the high density of C. utilis reduced the number of F. lucida population, the number of F. lucida showed decline trend along increment of diameter and height classes. The density increase of was in favor of F. lucida saplings from small diameter class to middle diameter class, which decline was good for saplings from middle diameter class to big diameter class. The high density of C. utilis reduced mean DBH (diameter at breast height) of F. lucida saplings, and increased mean height. Therefore, C. utilis could affect the quantitative structure and morphogenesis of F. lucida saplings, while F. lucida adapted to C. utilis clump environment by reducing DBH and increasing height.

Abstract:In order to understand the growth of Oxytenanthera abyssinica introduced from Ethiopia in Africa, the photosynthetic physiolgical ecology characters of two-year-old seedlings planted in Zhanjiang, Guangdong Province, China were studied. The results showed that the Chl a/b value was about 2.3∶1, the high Chl b content indicated that O. abyssinica had a certain tolerance of shade. When the light intensity ranged from 800 to 1600 μmol m^-2s^-1, the photo-inhibition of O. abyssinica was not appeared, showing strong light adaptability. There were good correlation between phenotypic traits and eco-physiological traits. According principal compenent analysis, the four factors, such as Chl b, ФPSⅡ, Chl a and Fo, were principal components, their accumulated variance contribution rate was up to 86.89%. The all seedlings were divided into four types by the cluster analysis. Therefore, there were significant differences in phenotypic and eco-physiological characters among O. abyssinica individuals, which would be provided with morphology and physiological basis in genetic breeding.

Abstract:To investigate the expression patterns of miR398 and miR408 in Phyllostachys edulis, the precursor sequences of ped-MIR398 and ped-MIR408 were isolated, and the expression of miRNAs was analyzed by real-time quantitative PCR (qPCR). The results showed that the length of precursor sequences of ped-MIR398 and ped-MIR408 were 83 bp and 92 bp, respectively, which both could fold into stable stem-loop structures, and the mature sequences (ped-miR398 and ped-miR408) were generated at 5' end of the arm in the stem-loop structures, respectively. The qPCR results indicated that both ped-miR398 and ped-miR408 were constitutively expressed, among which was most abundant in leaf blades. The expression of ped-miR398 and ped-miR408 were both up-regulated by the treatments of high light intensity, sucrose and GA₃, and they were both down-regulated by the treatments of CuSO₄ and ABA. Under the treatments of darkness, NaCl and 4℃, the expression of ped-miR398 was up-regulated, and that of ped-miR408 was down-regulated. Therefore, it was suggested that ped-miR398 and ped-miR408 might play different regulatory roles in the process of abiotic stress adaptation in bamboo.

Abstract:In order to screen appropriate reference gene for real-time qPCR (qRT-PCR) in Ananas comosus var. bracteatus at different development stages, the expression stability of 10 housekeeping genes, such as EF1, UBQ, ACT, GADPH, Histone, TUA, TUB, 18S, elf-5a, and α-tubulin, were detected, and the expression of PetF in seedling of A. comosus var. bracteatus was studied. The results showed that the expression stability of these genes in albino and green seedlings was different at development stages. Histone and α-tubulin were optimum reference genes at different development stages. Compared between green and albino seedlings, the ideal reference gene combination were 18S, EF1 and α-tubulin. The expression of PetF gene had the same variation trends in green and albino seedlings at three development stages by using screening reference genes. So, it was confirmed that the reference genes screened were suitable for qRT-PCR of A. comosus var. bracteatus.

Abstract:In order to select excellent strains of Eucalyptus grandis, the growth traits, quality traits and crown width of 173 families from 11 provenances at 53-month-old grown in alpestrine of south Yunnan were analyzed. The results showed that there were significant differences in growth traits, quality traits and crown width among provenances and families. The phenotypic and genetic variation coefficients of DBH, H, V, stem form, branch and crown width were 26.90%~28.84%, 23.84%~25.28%, 62.34~67.55, 13.04%~25.62%, 13.04%~25.41% and 35.07~39.93, respectively. The provenance heritabilities were ranged from 0.94 to 0.96 and the family heritabilities were ranged from 0.88 to 0.95. The correlation analysis showed that there were significant positive correlations between DBH with H, V, stem form and crown width, also between H with other traits. The correlation coefficient between stem form and branch were 0.70, while that between crown width with stem form and branch were -0.03. The genetic gain of V was the biggest among all traits, and it was 66.11% by 5% selection rate. The change trend of genetic gain in H, DBH, stem form and branch were similar under different selection rate whereas the rank of their genetic gain was different. The 17 families were selected under 10% selection rate by comprehensive index selection, which derived from No. 1 (Copperlode, QLD), No. 4 (Koombooloomba, QLD), No. 6 (Copperlode Falls Dam, QLD), No. 7 (Bambaroo, QLD), No. 9 (Tianma, Dongxi, Fujian), and No. 11 (Leshan, Sichuan) provenances. The provenances of No. 2 (Ravenshoe, QLD) and No. 8 (Tully Gorge National Park, QLD) grow slowly. The best six families were No. 289, No. 283, No. 2, No. 42, No. 121 and No. 82, derived from six selected provenances, indicating that the selected families not only had good growth and branch traits but also had rich genetic diversity.

Abstract:In order to selective breeding of Plukenetia volubilis L., the phenotype variations of its capsules and seeds were studied. The results showed that the capsules of P. volubilis had 3 types with 4, 5 or 6 pods, accounting for 49.71%, 37.69% and 12.60%, respectively, and the capsules with 4 or 5 pods were dominate. The variation coefficients of seed traits were lower than that of capsules, suggested that the stability of seed traits was higher than that of capsules. The traits of 4-pod capsule were the most stable among three pod types, there were 54.19%~95.63% variation ratio of traits came from different individuals. There were 79.81%~95.76% and 67.66%~93.0% variation ratio of capsule and seed traits came from pod type, respectively, which indicate the pod number had high effect on variations of traits. The most of traits of capsule and seed had significant differences among different pod types, the number of pod was main reason for trait difference. The seed germination rate was above 91% in the order of 6-pod > 5-pod > 4-pod. There were significant positive correlation between seed germination rate and weight per fruit, fruit morphology traits, such as fruit diameter, fruit thickness and thickness of pod, and weight per fruit, weight per seed and seed morphology, such as length, width and thickness. In conclusion, Plukenetia volubilis with 4-pod fruit had the highest yield, mean fruit and seed weight were higher than other types.

Abstract:In order to isolate and screen the taxane-producing endophytic fungi, there were 491 strains of endophytic fungi had been isolated and purified from young stems, barks and leaves of Taxus chinensis var. mairei. Twenty-five strains of endophytic fungi could produce taxane, in which four strains produce taxol, baccatin Ⅲ and 10-deacetyl baccatin, eight strains produce taxol and baccatin Ⅲ, one strain taxol and 10-deacetyl baccatin, one strain produce baccatin Ⅲ and 10-deacetyl baccatin, and six strains only produce taxol, and five strains only produce baccatin Ⅲ. Taxane-producing endophytic fungi derived from young stems, leaves and barks were eleven strains, nine strains and six strains, respectively. The yields of taxol, baccatin Ⅲ and 10-deacetyl baccatin Ⅲ were ranged from 0.64 to 9.87 μg L^-1, 0.48 to 3.42 μg L^-1, and 0.20 to 1.00 μg L^-1, respectively. Therefore, the taxane-producing endophytic fungi had wide distribution and more strains in T. chinensis var. mairei, and it could be good materials for studying metabolic pathways of taxane diterpenoids, and also could provide more potential fungal resources for taxane anticancer drugs.

Abstract:Pteroceras teres (Blume) Holttum (Orchidaceae), an epiphytic orchid from Yunnan is newly recorded for China. A detailed description of the species and photos are provided. This species is similar to P. compressum (Blume) Holttum, from which it clearly differs in having a terete rachis, spirally arranged yellow flowers and a spur with the bladdery apex laterally compressed, more or less twisted.

Abstract:The genus Hymenandra (A. DC.) A. DC and its type species H. wallichii A. DC. are for the first time reported from China. Recently in the course of naming the specimens of Ardisia in the herbarium of Kunming Institute of Botany (KUN), one of the authors came across some specimens that were evidently misidentified. After a close examination we found that they are actually the Himalayan species —— Hymenandra wallichii. It is new to the flora of China.

Abstract:Fissistigma thorelii (Pierre ex Finet & Gagnep.) Merr., collected in Honghe County, Yunnan Province, is newly recorded from China. The vouchers are kept in the herbarium of Xishuangbanna Tropical Botanical Garden (HITBC). This species is characterized by the overall rufous tomentose indumentum, and by the tuberculate epicarp.

Abstract:In order to understand the changes of alien invasive plants (AIPs) in Guangzhou during 2008-2016, the species number, origin, life form, invasive pathway and harmful degree of alien invasive plants were investigated recently in Guangzhou basing on combination of literatures and field survey. The result showed that there were 144 invasive species belonging to 38 families and 112 genera in Guangzhou in 2016, which were more than those in 2008 for 97.3%, 40.7% and 89.8% respectively. The 71 new alien invasive species were dominant with Fabaceae (14 species), Asteraceae (13 species), Convolvulaceae (6 species), Poaceae (6 species) and Rubiaceae (5 species). The AIPs mainly originated from America (104 species), and most of them were terrestrial herbs. More than 50% invasive species were introduced intentionally, and then invaded local ecosystem in Guangzhou. In addition, the alien plants at malicious and severe harmful degree took up about 40% of the total species, indicating that the urban forest ecosystem of Guangzhou have been facing serious threaten. Therefore, it is necessary to enhance the dynamics monitoring of alien plants, improve the risk evaluation of alien terrestrial herbaceous plants, and carry out the development and utilization of alien plants, so as to establish a stable ecological security patterns and safeguard the construction of green ecological city.

Abstract:In order to understand the relationship of spore development with morphology of floral organ in Osmanthus fragrans, the changes in morphology of floret organ during micro- and megaspores development of ‘Zao Zi Yin’ bisexual plant were observed. The results show that the meiosis of microspore mother cell started when flower bud at ball-shaped stage suddenly expanded, and it came into tetrad stage at top bract stage. Majority of microspore tetrads were tetrahedral, minority were decussate, and others between the two ways. Flower bud was at the bud-pedicel stage, microspore develop to the late uninucleate stage, and flower bud from bud-eye stage to full blooming stage, microspore form 2-celled pollen and mature, the anther length increased from 0.3 mm to 1 mm, color changed from colorless transparent to bright yellow. Pistil stigma two lobed, ovary 2 rooms, each room 2 ovules, amphitropous ovule, unitegmic, tenuinucellate, and funicle was not obvious. During two-cell pollen period, the megaspore mother cell goes on meiosis to form megaspore. To flowering stage, the 8-nuclear sac was mature with polygonum type. The development of stamen was earlier than that of pistils, they tend to mature at the same time after flowering. So, the micro- and mega-sporogenesis had high relation with morphology of floret organs. It was suggested that the micro- and mega-spore development period could be judged according to morphological characters of floral organs.

Abstract:In order to understand the chemical constituents of sweet star fruit [Averrhoa carambola L. (Oxalidaceae)], eight compounds were isolated from the fresh fruits by means of ethanol extraction, respective fractionation with ethyl acetate and n-butanol, and chromatographic separation techniques. On the basis of spectral data, their structures were identified as benzyl rutinoside (1), phenethyl rutinoside (2), adenosine (3), ethyl β-d-fructoside (4), n-butyl β-d-fructoside (5), gingerglycolipid A (6), gingerglycolipid C (7), and 4-hydro- xymethyl-5-hydroxy-2H-pyran-2-one (8). All the compounds were obtained from this species for the first time.