Abstract:

Abstract:The genus Greivia in Yunnan comprises 14 species and 3 varieties, of which 9 species and one variety are discussed in detail. G. glabra Bl. and G. lacei Drumm. et Craib are new to China, and G. macropetala Burret is for the first time reported from Yunnan. G. eriocarpa Juss. is treated as a variety of G. celtidifolia Juss. and six names, i. e. G. yunnanensis H. T. Chang, G. rotunda C. T. Wu ex H. T. Chang, G. urenaefolia (pierre) Gagnep. , G. hirsuts-velutina Burret, G. densiserrulata H. T. Chang and G. per...

Abstract:The development of anther and microspore in Hevea seedling and in Hevea clones RRIM 600 and GT-1 were observed, and the results are as follows: 1. Anther wall of seedling tree consists of four layers of cells and its formation is of dicotyledonous type. In later development stages some fibrous thickenings appear on the walls of endothecium cells,in which the protoplast remains until anther dehiscence. The middle layer consists of one layer of cells or two layers of irregular cells and disappears in monokary...

Abstract:This paper reports an investigation and study of some species of genus Gynostemma in Guangxi Genus Gynostemma includes five species in this area, i. e. G. guangxieitse X. X. Chen et D. H. Qin, G. compressun X. X. Chen et D. R. Liang, G. laxum (Wall. ) Cogn, G. pentaphyllum and G. longipes Wu et Chen. The ecological environment and geographical distribution of genus Gynostemma in Guangxi were analyzed. It gives a data for exploitation and utilization of Gynostemma.

Abstract:The Succession of the forest communities at Dinghushan is to tend to climax following the objective law under the natural condition. The paper analyses the successional results of forest on the area from 1955 to 1989,and summarizes the successional process and model, and then proceeds to make to quantitative research with the pattern of linear and un-linear system , The relatitivant numerical expectations of the successional process are calculated . It is shown by the researched examples in this paper tha...

Abstract:The dynamic of fine root biomass in mineral soil up to 45cm and their chemical composition were investigated in a 25 years old grand fir stand on a pseudogley soil from the waterlogged period to the vegetation period (November 1987-September 1988) . Under waterlogging the fine roots had considerably higher dead mass (5558 kg DS/ha) than living mass(3594 kg DS/ha). At the start of the vegetation period the total mass of the living fine roots increased by 50% and the total mass of the dead fine roots decrea...

Abstract:The characters of male sterile (MS) line 54257/162-5 were described , both the female 54257 and male 162-5 parents of which were Somaclones derived from IR54 and IR52 respectively. The MS line 54257/162-5 being stable was produced in the 8th generation by backcross-ing. The frequency of MS plant in the population wsa 100% , the pollen was abnormal and seedless in the condition of self pollation. Although all pollens were abortive, the pollens about 30% of the individuals were non-stainable, 50% stainable ...

Abstract:By application of appropriate vectors together with DNA renaturation kinetic method, repetitive DNA sequences of different Cot value were cloned from rice ( Oryza sativa L. ) genome. Two promoter selection plasmids, pKK175-6 and pKK232-8, were used as cloning vectors, which contained promoters Tet or Cat gene, respectively. The recombinant clones acquired resistance to Tc or Cm, and their resistant levels varied from 20μg/ml to 80μg/ml Tc or 30μg/ml to 260μg/ml Cm. The sequence analysis showed that there we...

Abstract:The uptake of ³H-BA by leaf discs of peanut existed in two forms, active and passive forms, and the latter was about 60. 7% of total amount absorbed. When leaf discs were incubated with ³H-BA, the maximum amount of this chemical taken in was found after 2 hours and then decreased. A pH optimum at 7. 5 could benefit the ³H-BA uptake by leaf discs. At the range of 16- 26℃, the amount of BA absorbed by leaf discs was increased with temperature. When the leaves of decapitated-derooted peanut plants were smear...

Abstract:The endopeptidase activity in high-vigor peanut ( Arachis hypogaea L. )seeds increased rapidly from the 2nd day to 4th day after imbibition and reached its peak at the 4th day after imbibiton, while the endopeptidase activity in medium-vigor seeds increased slowly after imbibition. The contents of salt-soluble proteins and arachin in high-vigor seeds declined more rapidly .than those in medium-vigor seeds, pretreatment with PEG and PUT enhanced both the vigor and the degradation rate of storage proteins of ...