Abstract:Three protein modifiers, butanedione (BTD), N-bromosuccinimide (NBS) and ρ-Chloromercuribenzoic acid (ρCMB), were used to treat cells of a green marine alga, Dunaliella salina. The photosynthetic oxygen evolution and absorption spectra were studied by oxygen electrode and spectrophotomeler. All of the used modifiers inhibited the photosynthetic rate of Dunaliella salina to a certain extent. The inhibition was 14.6% (BTD, 0.21 mmol/L), 21.4% (NBS, 0.02 mmol/L) and 39.7% (ρCMB, 0.1 mmol/L), respectively. A c...

Abstract:Stevioside accumulation in callus cultures derived from Stevia rebaudiana leaf explants was studied during callus growth and differentiation. Increase in stevioside content was positively related to the organization of cells and greening of the cultures, and inversely to the callus growth. Shoot formation in calli was not essential for the synthesis of stevioside. The content of stevioside was highest in slow-growing, compact and green calli either with or without shoot formation. Electron microscope observ...

Abstract:Some substances with activity of superoxide dismutase (SOD) extracted from fresh algae can scavenge superoxide radical (O). The activity of SOD in algae is usually 60 - 280 U g-1FW, but that in Ulva pertusa, Gracilaria verrucosa and G. eucheumoides is higher (about 300 U g-1FW). In general, the activity and stability of SOD in algae are in order: green algae>red algae>brown algae. The main types of SOD in green algae are CuZn-SOD, but in blue algae, Fe-SOD. The result of PAGE and SOD active staining of the ...

Abstract:Some physiological and biological characters of three types of two-line F1 hybrid rices: Indica-Japonica (W61 54s/02428), Indica-Javanica (W6154s/Lunhui422), Indica-Indica (W6154s/Lemoney) were studied. The analyses of tillering ability, amylase activity of germinated seeds, and absorption capacity of roots at seedling stage showed a tendency to be in the order W61 54s/02428 >W6154s/Lunhui422 >W61 54s/Lemoney >Weiyou 64. Root absorption capacity of two-line F1 hybrid rices during seed sprouting showed nega...

Abstract:The photosynthetic pathway of 10 cultivars of 7 species in Cymbidium were studied. The results showed that in Cymbidium leaves, the activities of phosphoenolpyruvate carboxylase (PEPCase) and pyruvate phosphate dikinase (PPDK) were very low, but the activity of glycolate oxidase was rather high. The glycolate content in the leaves treated with α-hydroxypyridine methane sulfonate (α-HPMS) was obviously higher than that of control under the light. Chlorophyll a/b ratios in these cultivars were between 1.24 an...

Abstract:Embryogenic calli derived from mature zygotic embryos of loblolly pine (Pinus taeda L.) of three genotypes from Hunan Province, viz. Shaoyanghigh-2, Yongshunmiddle-1 and Yongshunmiddle-3 were used in embryogenic cell suspension culture. Parameters in the growth of cultures, including fresh weight, dry weight, packed cell volume, somatic embryo number, as well as pH, conditivity, and sucrose concentration of the culture medium were measured during culture period. The results showed that, during culture circl...

Abstract:The leaves of cucumber (Cucumis sativus) seedlings were sprayed with 0.1 % - 0.6% thiodan, and after 4 days the contents of total chlorophyll, chlorophyll a, chlorophyll b,protochlorophyll and carotenoids were decreased by 21 .00% - 38.57%, 21 .27% - 38.69%, 20.22% - 38.24%, 6.60% - 49.24% and 13.54% - 68.85%, respectively. Thiodan at 0.1% -0.6% concentrations caused the promotion of chlorophyllase activity by 16.51 % - 72.80%, and decreased the activities of δ-aminolevulinate synthase and δ -aminolevulinat...

Abstract:The authors have observed the chromosome numbers of 12 mangrove species growing on the salty and muddy coasts and 2 island species belonging to Rhizophoraceae and Sonneratiaceae in China. The chromosome numbers of seven taxa, namely Bruguiera sexangula, B. sexangula var. rhynchopetala, Rhizophora stylosa, Sonneratia hainanensis, S. paracaseolaris, S. ovata and Carallia brachiata, are reported for the first time, which give a supplement to chromosome data of Chinese mangroves. Fourly-four names, which repres...

Abstract:Dunnia assamica (Hook. f.) Ridsd. is reduced to a synonymy of Neohymenopogonassamicus (Hooker f.) Bennet.

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Abstract:An investigation of endangered monotypic species Monimopetalum chinense (Celastraceae) was carried out in Jiangxi Proyince during recent years. The factors that caused this species endangered can be focused on (1) the obsctruction in seed germination due to solid seed coat; (2) poor pollination and ovule-obortion; (3) embryo dormancy or dehydration after maturing of the seeds; and, (4) serious environmental disturbance by human factors. Some suggestions for the conservation of the species are made.

Abstract:Changes of species diversity and eco-environment at different successional stages in degraded ecosystem of subtropical monsoon evergreen broad-leaved forest were studied from January 1994 to October 1995, in Wuhua county, Guangdong Province, where the sites surveyed were low hills at 160 -180 m altitude. The forest coverage here was only 2.2%. and soil erosion accounted for 61.1% of the total sites studied. Three fixed plots were set up in different communities, namely secondary forest (400 m2) that had bee...

Abstract:The essential oil from leaves of Abies forrestii C. C. Rogers was extracted by steam distillation and analyzed by GC-MS technique. The results show that the major chemical constituents of the essential oil are α-pinene, β-pinene and limonene.

Abstract:The experiments of 38 species of Magnoliaceae plants propagated by grafting show that close affinity exists among different genera of Magnoliaceae, and most species can be grafted intergenerically. Grafting time and kinds of stock are the major factors which affect the grafting survival rate of Magnoliaceae, but the grafting methods have less influence on the growth of the plants. The grafttings are more adaptive to the environment and grow faster than the seedlings.

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