Abstract:Based on consecutive measurement from 1981-1990 at Xiaoliang ExperimentalStation in Guangdong, the energy balance in three ecosystems, mixed forest, eucalyptus forest and bare land, was studied comparatively. The reflection rate to solar radiation wasin the order bare land ＞eucalyptus forest ＞ mixed forest. The net radiation (NR) on bareland was 1.57 times of that on mixed forest and eucalyptus forest. The energy dissipationby evapotranspiration was 95% of NR for mixed forest, 59% of NR for eucalyptus forest and 70％ of NR for bare land．The heat conductivity of soi1 changed a little in different ecosystems and various seasons， but the regularity was not apparent．Annual heat flow through soil was nearly balanced for bare land，which differed from that for mixed forest and eucalyptus forest．As a whole，the heat environment was best in mixed forest and worst in eucalyptus forest，which was shown by that the output of energy from the mixed forest was mainly through evapotranspiration and that from the eucalyptus forest was mainly through air movement．This is why the micro-climate in mixed forest is warm and wet but that in eucalyptus forest is hot and dry．

Abstract:Flowering and fruiting phenologies, and fruit and seed dimensions were analysedfor the woody plants in the floras of Hainan -Guangdong , Qinling and North-east China.Similar seasonal patterns of flowering and fruiting phenologies were found among thewoody floras, although the flora at lower latitude had longer flowering and fruitingperiods in the year, and had a peak of flowering appearing earlier and a peak of fruitingappearing later than the flora at higher latitude. Frequency distributions of fruit and seed sizes also showed similar patterns，although the range of fruit and seed dimensions became narrower with the increase of latitude The smallest dimension of fruit (0.1 cm) was similar among the floras， but the smallest dimension of seed became bigger with the increase of latitude Relationships between the flowering and fruiting phenologies and the air temperature and rainfall were different among the floras．More obvious correlation was found between the fruit ripening and the climate factors than between fruiting phenology and the climate factors for the common woody plants in Dinghushan Biosphere Reserve，Guangdong Province．

Abstract:Based on the vegetation survey on a secondary evergreen broad-leaf forest atSanjiaoshan, Conghua, near Guangzhou, the natural distribution characteristics,environmental condition, floristic composition and community characteristics of China'sendemic species Manglietia pachyphylla Chang and its conservation strategies were studied in June, 1997. The results indicated that Manglietia pachyphylla was naturally distributed inthe secondary evergreen broad-leaf forest at altitudes from 650 to 1 000 metres in a narrow zone．There were 132 species of vascular plant in 89 genera of 57 families in plots of 1 200 m². The diversity index and evenness of the tree and shrub species in the community were 5.45 and 84.39％，respectively，which were similar to those of other evergreen broad-leaf forest in the neighboring regions， but lower than those in tropical rain forest in Hainan. The floristic composition of the community showed a transitional characteristics of tropical and subtropical elements．The community was termed as Syzygium buxifolium + Daphniphyllum subverticillatum + Manglietia pachyphylla Community．It can be vertically divided into three layers，tree (with 2 sublayers)，shrub，and grass layers．There were many species in the tree layer and shrub layer， but few species in the grass layer．The dominant species of Magnoliaceae in tree layer were found to be Manglietia pachyphytta and Michelia maudiae. The mesophanerophytes and microphanerophytes made up high percentage，and the megaphanerophytes，Hemicryptophytes and therophytes were not found in the species life form spectrum of the community．The mesophyll also made up high percentage in leaf-size class spectrum of the community．The distribution pattern of magnoliaccous plants were measured by variance／means ratio．and the result indicated that most of the dominant species were clumped in distribution，Manglietia pachyphylla and Michelia skinnerana were clumped，and Michelia maudiae was random．Analysis on structure of magnoliaceous populations indicated that Michelia maudiae and Michetia skinnriana were at the stable stage，but Mangtietia pachyphylla expressed a decline tendency．Therefore，Manglietia pachyphylla is an endalagered species which must be preserved through in situ and ex situ conservation，and the preservation strategies should be centred on in, situ conservation.

Abstract:In this paper, a new modified Shannon-Wiener index for measuring species diversity is established by using fractal theory, and the evenness formula is deduced. The new indexand the evenness were used in measuring the species diversity of Castanopsis carlesiicommunity with an area of 100 m² to 1500 m² in Wuyishan National Nature Reserve. Theresults showed that the new index could objectively reflect the property of species diversity,and that is worthy of application in practice as a new model.

Abstract:Transplanted 2 to 3-year-old seedlings of Castanopsis fissa, Schima superba,Cryptocarya concinna and Pinus massoniana from Dinghushan subtropical forest were pottedunder 16%, 40% and 100% of full sunlight for 16 months. Growth and dry masspartition at all light levels were measured. Seedlings of P. massoniana survived much betterin full sunlight than in shade, other 3 broad-leaf species survived well in both conditions.Seedling heights and diameters of P. massoniana and C concinna after transplanting for 16 months were greater in full sunlight than in shade．The number of branches declined with decreasing light intensity for all species．The number of leaves was greater in shade than in full sunlight for C．concinna and C．fissa, but lower for S．superba, when leaf fall was negligible．Expressed as a portion of peak dry mass at 100％，the relative whole plant dry mass for species grown under 40％ and l6％ sunlight was 57.4％ and 32.7％ (P. massoniana) 73.8％ and 62.1％ (C. concinna)，78.O％ and 78.6％ superba)，93.9％ and 76.2％ (C.fissa)，respectively．For Castanopsis fissa，Schima superba，aboveground dry mass showed little variation among treatments，but root dry mass declined with decreasing light intensity，while both above-and underground dry mass for Cryptocarya concinrla，Pinus massoniana dropped markedly with decreasing light intensity．Crown-root ratio (CRR)，leaf-plant weight ratio (LWR)，leaf area ratio (LAR) and specific leaf area (SLA) were higher in shade than in sunlight for all the 3 broad-leaf species．P．massoniana，a sun-loving species，had much limited potential in acclimating shade environment, while C. concinna was considered shade-tolerant species，yet grew more rapidly in full sunlight．

Abstract:Measurements were made of photosynthesis-light response curves, leaf stomatalconductance, intercellular CO₂ concentration, water use efficiency (WUE), chlorophyll andnitrogen contents in leaves of 2-to 3-year old seedlings of Betula pendula, Fagus sylvaticaand Quercus robur potted under two contrasting light (full light and 20% full light) regimesin indoor condition in Germany in September, 1989. Regression relationship between netphotosynthetic rate and chlorophyll content was also analysed .The seedlings grown under 20％ full light condition showed a lower net photosynthetic rate and light-saturated point，lower stomatal conduetance and WUE，lower chlorophyll content per fresh weight unit of leaf and the reduced accumulation of dry matter compared to those grown under full light．A positive correlation was found between chlorophyl content and net photosynthetic rate．Seedlings of the three examined tree species could deal well with the shadiness under forest．Betula pendula and Quercus robur would be more capable of adaptation to shady environment than Fagus sylvatica．

Abstract:When etiolated seedlings of mung bean (Phaseolus radiates L.) were treated with exogenous ethylene at 25℃, the respiratory peak of hypocotyl mitochondria appeared earlier, the maximum of the respiration was higher than the control, and the rate of cyanide-resistant electron transport pathway increased more rapidly than that of the cytochrome pathway. After the respiratory rate was decreased for a long time (15 h), the rate of production of superoxide radical (O₂^-.) still kept rising. To test the role of superoxide radical in accelerating respiration，the effect of exogenous superoxide radical which was generated from the system of xanthine and xanthine oxidase on respiration was examined．It was found that the respiratory peak also appeared earlier than the control．Acoording to the above result，we draw a conclusion that ethylene stimulates the rate of mitochondrial respiration that is due to the increase of the O₂^-. production rate，through stimulating the rate of electron leak of respiratory chain． This may he one of the mechanisms of the effect of ethylene on mitochondrial respiration.

Abstract:Curcuma albicoma S. Q. Tong and C. chuanyujin C. K. Hsieh et H. Zhang arereduced to synonyms of C. sichuanensis X. X. Chen and C. kwangsiensis S. G. Lee et C. F.Liang, respectively. Curcuma phaeocaulis Val. was misidentified as C. zedoarea (Christm.)Rose., C. caesia Roxb. and C. aeruginosa Roxb. in China. Curcuma elata sensu X. X. Chenis C wenyujin, and C kwangsiensis var. puberula Y. H. Chen and C kwangsiensis var. affinisY. H. Chen are not to be recognized, while C. viridiflora Roxb. in F1. Taiwan remains suspicious. A key of 12 species of curcuma in China is given.

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Abstract:Somatic embryos could be induced from axes of mature peanut embryos culturedon hasal MS medium containing high concentration of 2,4-D (40 mg L^-1) with 0.5 mg L^-1 kinetin, 30% sucrose and 0.9% agar for 30 days, the induction rate being 100 percent,and the mean embryo number per explant reaching 11.58. Lower concentrations of 2,4-D(10-20 mg L^-1) were suitable for somatic embroid differentiation in subculture. However,10 mg L^-1 2,4-D was the optimum concentration for inducing somatic embryos both in primary culture and in subculture by immature embryo axes．Somatic embryos could easily germinate on MS medium with 5-10 mg L^-1 BA. The plantiets were obtained after the shoots were tranferred to root-inducing medium, MS+ 2 mg L^-1 NAA．

Abstract:Procedures were developed for the micropropagation of longan (Dimocarpus longanLour.) using lateral and terminal shoots from seedlings and graftings of 6-year-old treesgrown in reticular plot. Shoot apex culture was established in two steps: sterilized explantswere first cultured for 30 days, then the 2 mm long segments of shoot apexes from axillarybuds were taken and cultured on induction and multiplication media. Four indexes wereused to evaluate the growth of cultures, i.e. the death rate, induction rate，leaf number，and the fresh weight．Of the media and explants examined，the best culture establishment was obtained with shoot apexes cultured on MS medium supplemented with 0.3 mg L^{-1 6-BA，O.1 mg L-1 IAA and 3％ sugar．Optimum hormones for shoot apex multiplication were O.1-0.2 mg L-1 6-BA， 0.1-O.5 mg L-1 KT and 0-0.3 mg L-1 IAA，the multiplication rate being 3.05 times. Treatment in liquid culture with 0.01 mg L-1 6-BA and 1.0 mg Lmg L-1 IBA in combination was best for rooting, the rooting perce ntage reaching to 34.1％．}

Abstract:Five grains pure mycorrhizal inoculum of Pisolithus tinctorius (Pt) was injected toeach seeding of Eucalyptus grandis × E. urophylla before transplanting for one month inexperiment plots of Gaofeng Forest Farm near Nanning City, Guangxi. The sustainedeffect of Pt on the increments of plant growth height and tree volume were remarkable,being by 16.34% at the tree age of 3 months and 18.5% at tree age of 16 months,respectively, as compared to the control. The survival rate of seedings after transplanting for 3 months was increased by l5.76％ compared to the control，and the total increments of the tree volume were obvious eigther in young trees or in trees of harvest cutting．The economic profit from the forest would be ten times the cost of mycorrhizal investment.

Abstract:Using the egg protein as standard protein and WHO/FAO reference model ofessential amino acid (EAA) as an appraisal criterion, and 11 kinds of common foods ascontrol, the authors evaluated the nutritional value of the protein in the seeds of Celosiaargentea and C cristata cv. Childsii by method of fuzzy discernment and method of ratiocoefficient of amino acid (AA). The results showed that the protein quality of the seeds wassuperior to that of some beaus, potatoes and cereals, and the seeds may be considered as a potential valuable sourse of plant protein.

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