Abstract:Illicium lanceolatum A. C. Smith, an important and endangered medicinal plant of China, has declined rapidly in population size in recent years. Interspecific associations, which play an important role in ecosystem function, can reflect interspecific competition within community. The species association in I. lanceolatum community was studied based on 2×2 contingency tables of species, including analysis of species association and χ2 test. The results showed that the significant positive associations [W(49.607)＞χ20.05,32(46.194)] were present among the tree species as a whole in the community. The percentage of species-pairs with significant positive association among them was higher than that with significant negative association, and the number of species-pair without significant association had the highest percentage, which implied that the community was stable. There were significant positive associations between I. lanceolatum and species, such as Photinia serrulata, Eurya acutisepala, Castanopsis sclerophylla and Symplocos setchuensis etc., and the significant negative association only occured with Liquidambar formosana, but it had no correlationship with most species. The association coefficients (AC) between I. lanceolatum and most species are more than 0.5 (about 74.3%), with positive species-pairs more than negative, which implied a dominant status of I. lanceolatum in the community and a coexisting relation with other species. These results can provide a valuable reference for the population protection, in situ, rehabilitation and planting mode and habitat selection.

Abstract:The effect space of tree competition in the artificial mixed forest of Cunninghamia lanceolata and Tsoongioden odrum in Dong’an Forestry Farm of Jian’ou, Fujian Province, was divided into two parts, inside radius and outside radius. The interspecific and intraspecific competition intensities of C. lanceolata and T. odrum were analyzed by using Hegyi’s Individual Tree Competition Index model. The results showed that all competition intensities of C. lanceolata, including intraspecific competition and interspecific competition, reduced with increasing of tree diameter classes in the both competition radiuses. The order of competition intensity was followed as intraspecific competition intensity of C. lanceolata in the inside radius > interspecific competition intensity of T. odorum in the inside radius > intraspecific competition intensity of C. lanceolata in the outside radius > interspecific competition intensity of T. odorum in the outside radius. The competition intensity in the forest was predicted by the simulation model, which indicated that some management measures should be conducted to decrease the competition intensities of C. lanceolata before the diameter at breast height of C. lanceolata up to 36 cm.

Abstract:Two hundred and fifty-eight bryophyte samples were collected from Guizhou Lannigou Gold Deposit which is the biggest carlin gold deposit in Asia. The bryoflora of this site included 15 families, 37 genera and 81 species. Pottiaceae, Bryaceae, Ditrichaceae and Bartramiaceae are four dominant families, which were adapted to their environment. Contents of Au, Cu, Zn, Pb, Cd, Cr, Co, As and Hg in 6 bryophytes [Pylaisiella polyantha, Bryum pallescens var. pallescens, Ditrichum heteromallum, Weisia planifolia, Weisia semipallida, and Cyrto-hypnum versicolor] and corresponding substrates were determined by using Atomic Absorption Spectrometer and Atomic Fluorescence Spectrometer. The results showed that the average concents of As and Hg in soil are 222.378 mg kg-1 and 23.516 mg kg-1, respectively, which are 5.56 times and 15.68 times of the third class standard (40 mg kg-1 for As, 1.5 mg kg-1 for Hg) of National Environmental Quality Standard for Soil. The pollution situation is serious. In addition, Bioconcentration factor show that each species of bryophyte accumulate 3 kind of heavy metals at least. Therefore, all of 6 species in this study can be used in mines polluted by heavy metals as pioneer plants for ecological restoration in further research.

Abstract:The spatial variability of plant species richness was analyzed using geostatistics in the Karst area of Bijie, Guizhou Province, which presents wide altitudinal range in southwest China. The optimal semivariogram theoretical model fitted for arbor species richness was spherical model, and the linear sill model for shrub and herb. The arbor species richness was highly related to altitudinal gradient with a spatial heterogenous rate of 0.0052, which mainly affected by natural controlling factors with altitudinal variation. Shrub and herb species were mainly affected by random factors, which showed very weak relationship with altitudinal gradient and their spatial heterogenous rates were 3.15 and 34.55, respectively. The altitudinal range of arbor species richness was 177.37 m, which indicated a wide altitude range affected by random factors. The altitudinal range of species richness of shrub and herb were 73.02 m and 49.97 m, respectively, which indicated a narrow altitude range affected by random factors. The changes of Moran’s I index of shrub and herb species along altitudinal gradient were similar that were different from that of arbor species.

Abstract:Twelve ISSR primers screened from 100 primers, were selected to analysis the genetic relationship of 22 materials belonging to 16 mango (Mangifera indica L.) cultivars or lines selected and breeded by the Guangxi Institute of Subtropical Crops. The results showed that 85 scorable polymorphic bands of a total 127 bands were produced and percentage of polymorphic bands was 66.93%. Based on UPGMA analysis, all samples showed higher similarities and their coefficients were more than 0.81. If the coefficient 0.82 was regarded as divided line of their genetic relationship, 22 materials could be clustered into three groups by ISSR. The genetic relationship of Gui Re Mango cultivars or lines could be better assessed by ISSR-PCR.

Abstract:The effect of low temperature on the allelopathy of aqueous extraction from Galinsoga parviflora Cav. was studied by using micronucleus assay in Vicia faba root tip cells. The results showed that the mitotic index of V. faba root tip cells treated with the aqueous extraction decreased and micronucleus and aberration rates increased under normal temperature. However, after G. parviflora was treated at low temperature, the mitotic index of V. faba root tip cells soaking in low concentration of aqueous extraction enhanced and it decreased in high concentration of aqueous extraction, but micronucleus and aberration rates increased significantly. These suggested that low temperature stress could chang the allelopathic effect of G. parviflora.

Abstract:Effects of temperature on peel color and physiological changes of banana fruits during ripening were investigated. Fruits were dipped in 0.1% ethephon for 1 min, and then ripened at 20℃ and 30℃, respectively. The changes in peel colour, contents of starch and soluble and activities of cell wall degradation-related enzymes, such as polygalaturonase (PG), pectinmethylesterase (PME) and cellulase, were measured. The results showed that banana fruits degreened and softened normally during ripening at 20℃, while ripening at 30℃, the fruits hastened the softening and inhibited the degreening of the peel, resulting in the development of a pale greenish yellow colour. Furthermore, compared with the fruits ripened at 20℃, the starch in fruits ripened at 30℃ enhanced the conversion to soluble sugar, and the activities of PG, PME and cellulase were increased. It was suggested that there were relationship between green-ripe banana fruit at high temperature and soluble sugar in peel, but irrelevant to softening-related physiological changes.

Abstract:The global protein patterns in normal and aborted embryo of litchi at 40 days after flowering (DAA) were compared by using two-dimensional polyacrylamide gel electrophoresis (2-DE) and computer image analysis. The results showed that the quantities of 100 protein spots in normal embryo were significantly different from aborted embryo. There were 15 and 50 spots appeared on the gel of normal embryo and aborted embryo, respectively. Then they were selected for MALDI-TOF-MASS analysis. Nine proteins related with embryo development were identified, which maight involve in regulating and controlling the embryo abortion.

Abstract:Fruits of pummelo [Citrus grandis (L.) Osbeck ‘Guanxi-miyou’] from old-age trees occurred easily juicy sac granulation and proper-age trees not occurred juicy sac granulation were used to study the relationship between juicy sac granulation and cell wall metabolism during the fruit mature stage. The index of juicy sac granulation of fruits from the old-age trees increased with fruit maturing. Pectinesterase (PE), polygalacturonase (PG) and cellulase in juicy sacs kept low activities, and the contents of protopectin, cellulose and semicellulose were high during the development of juicy sac granulation. At the early and the rapid developmental stages of juicy sac granulation, the contents of cellulose and semicellulose were enhanced significantly. In contrast, the index of juicy sac granulation of fruits from the proper-age trees had little change with the fruit maturing. The activities of PE, PG and cellulase in juicy sacs were high and the contents of protopectin, cellulose and semicellulose were low. It suggested that the activities of PE, PG and cellulase, and the contents of protopectin, cellulose and semicellulose were closely related to juicy sac granulation of pummelo fruits.

Abstract:The collection, morphology characters and culture condition of pollens of Magnolia sieboldii were studied, and the effects of storage temperature and time on pollen viability were investigated. The pollen morphological characters and germinal aperture of Magnolia sieboldii under scanning electron microscope are similar to that of the other species in Magnoliaceae, but the size and exine sculpture are different. The pollen collected in the initial bloom stage has the highest germination rate at 25℃. Pollens cultured on medium with 10% sucrose and 0.1% boric acid for 14 hours had the highest germination rate. The 0.01%~0.05% CaCl2 had no significant effect on pollen germination, but 0.1% CaCl2 had negative effect. The viability of pollen of Magnolia sieboldii decreases gradually as increasing of preservation at different storage temperature, and the pollen viability are decreased in order of 25℃>4℃> -10℃. The pollen germination rate reduced from 87.9% to 48.8% when they were stored at -10℃ for 5 days and reduced to 0 for 10 days.

Abstract:The karyotypes of three hybrids and their parents in Magnoliaceae were studied. Their karyotype formulae are as follows: 2n=2x=38=36m+2sm for Michelia yunnanensis, 2n=2x=38=34m+4sm for Michelia calcicola and 2n=2x=38=26m+12sm for their hybrid A; 2n=2x=38=32m+6sm for Michelia crassipes and 2n=2x=38=24m+12sm+2st for hybrid C from Michelia crassipes and Michelia yunnanensis; 2n=2x=38=28m+10sm for Magnolia delavayi, 2n=6x=114=88m+10sm+16st for Magnolia grandiflora and 2n=4x=76=57m+15sm+4st for their hybrid U. The results showed that the karyotypes of these hybrids were markedly different from the expected ones according to the parental karyotypes, which might result from the structural variation of the parental chromosome during the hybridization. Therefore, it is difficult to identify these hybrids by the karyomorphological characters.

Abstract:A new species of Lauraceae, Machilus attenuata F. N. Wei & S. C. Tang, is described and illustrated from Guangxi, China. It is closely related to M. dinganensis S. Lee et F. N. Wei, differing in its leaf apex caudate acuminate or long acuminate, base attenuate and slightly decurrent, and adaxial surface glabrous when young. It also resembles M. sichourensis H. W. Li, from which it differs in the leaves thinly coriaceous, oblanceolate or elliptic, smaller (8~13 cm long, 2.2~4 cm wide), gradually narrowed or slightly decurrent at base, and with lateral veins indistinct or slightly distinct adaxially and distinct abaxially.

Abstract:Two genera, Rhynchoglossum Blume and Epithema Blume, represented by R. obliquum Blume and E. carnosum Benth. respectively, are reported as new records from Hainan Province.

Abstract:Based on specimen collection of seed plants from Tianmengshan National Forestry Park in Zhangjiajie, Hunan Province, two genera, thirteen species, and two varieties, belonging to 11 families and 15 genera, were reported as new records from Hunan, China. The newly recorded taxa were Sedum filipes Hemsl., Sinocrassula indica (Decne.) Berger var. viridiflora K. T. Fu, Saxifraga rufescens Balf. f. flabellifolia C. Y. Wu et J. T. Pan, Malus yunnanensis (Franch.) Schneid., Hovenia dulcis Thunb., Acer olivaceum W. P. Fang et P. L. Chiu, Bupleurum longiradiatum Turcz., Agnelica biserrata (R. H. Shan et C. Q. Yuan) Yuan et R. H. Shan, Notopterygium incisum T. T. Ting ex H. T. Chang, Ancylostemon saxasilia (Hemsl.) Craib, Leptodermis potanini Batalin, Dendranthema vestitum (Hemsl.) Ling, Salvia plectranthoides Griff., Allium victorialis Linn. and Polygonatum nodosum Hua. Among the taxa listed above, Notopterygium and Leptodermis were new record genera in Hunan. All of the voucher specimens were preserved in Dendrological Herbarium of Central South University of Forestry and Technology (CSFI).

Abstract:The name Morinda shuanghuaensis C. Y. Chen et M. S. Huang described from Guangdong Province, China in 1976 was found not validly published because two collections (one fruiting, one flowering) were designated as types. The name is validated here, with the fruiting specimen designated as holotype. Meanwhile, a lectotype is proposed for the name Morinda howiana S. Y. Hu.

Abstract:Moringa oleifera introduced from Myanmar was grown in some dry-hot valley areas of Yunnan Province. Propagation methods of direct sowing and sapling transplanting in the spring were applied, and three types of planting sites were experimented with M. oleifera for three years, i.e., irrigated farmland, farmland without irrigation and the waste sloping land in the mountainous area.. The following results were concluded from the three year introduction experiment. (1) The M. oleifera plants grown on the farmland by the both two propagation methods could normally bloom and bear fruits in the first year. The plants grown on the waste sloping land could not bear fruits or bear little in the first year, and the young shoots of some plants severely dried out because of the drought. While the trees planted on the former farmland could bear some fruits, but the yield was lower than that on the farmland. (2) The development rhythm of M. oleifera bearing basal shoot and fruit spurs was different from most of tree species. The fruit spurs of different ages could simultaneously develop on the same fruit bearing basal shoots, and the same fruit bearing basal shoot could produce fruit spurs continuously for many times. (3) The peak period of fruit elongating growth was earlier than that of girth growth. (4) Fruits consumed as fresh vegetable should be harvested before fibrosis, which took place from the elongating growth of the fruits ended to the girth growth stage started. (5) It was demonstrated by the preliminary results of the experiment that M. oleifera was a moderate drought resistant species, and it might fit to be planted in arid or semiarid areas in tropical or sub-tropical climate zones in China. It was recommended that great attention should be paid to planting site selection before the cultivation area is extended.

Abstract:Division of labor is an engine of economic progress. A similar phenomenon also exists in clonal plants. The basic conditions for the division of labor in clonal plants includes: environmental heterogeneity, specialization, cooperation, and the potential independence of ramets. According to these conditions, division of labor in clonal plants could be classified into two types, i.e., environmentally induced and developmentally programmed division of labor. Clonal plants can efficiently utilize the heterogeneous resources by means of physiological integration and morphological or physiological plasticity. Division of labor in clonal plants could raise the acquisition efficiency of the local resources, overcome the local resource limitation and enhance the biomass and fitness. These effects could be explained by the theory of marginal cost and scale reward in economics. Division of labor in clonal plants can also enhance the competitive capacity of inter-specific competition, reinforce the efficiency of foraging behavior, and weaken the effects of self-thinning. The risks of division of labor in unstable habitats also exist. The application of the methods of modern biology, the studies on the division of labor in clonal plants will be promoted.