Cell plating clone technique was employed to screen clone lines with high yield of oligosaccharins from culture cells of Panax ginseng C. A. Mey. Near 300 clone lines were obtained. The results from some clone lines analysed implied that these clone lines were significantly different in cell growth rate, oligosaccharins content and yield. Furthermore, there was a distinct correlation between oligosaccharins productivity and cell growth. A more stable high-yield oligosaccharin clone line PG-180 had been selected according to the characteristics of growth rate, oligosaccharin yield and peroxidases isozyme patterns during successive subculturing of 11 generations of clone lines. The mean growth rate of clone line PG-180 was 0. 495 g dry wt/L · d, and was 1.39 folds higher than to the original strain. Its mean content and yield of oligosaccharins were 14. 69 % dry wt and 2.183 g/L, which were 65 % and 132% respectively higher than those of the original strain. In comparing the time course of cell suspension culture between clone line PG-180 and the original strain, the optimal period for high oligosaccharin production from P. ginseng culture cells was approximately three weeks.

Lotus corniculatus L. is a common legume forage, l0 kD zein is a maize storage protein in which about 25 % of total amino acids contain sulphur. The chimeric plasmids of the 10 kD zein gene regulated by rbcS promoter and CaMV 35S promoter were introduced into L. corniculatus by Agrobacterium tumefaciens mediated procedures, and the transformed plants have been obtained. Kanamycin-resistance of plantlets was evidenced by the presence of enzyme activity from NPT Ⅱ assay. Southern blotting indicated that the 10 kD zein gene had been integrated into the chromosomal genome of L. corniculatus.

The parenchyma cells in the detached garlic scape undergo regular breakdown of cellular constituents and withdrawal of the degrading protoplasm. Autophagic vacuoles from endomembrane components are involved in the degradation process. The bulk of the products from degradation of the protoplasts are removed by both symplastic and apoplastic pathways from the senescing parenchyma cells and are used as nutrients for the growth of aerial cloves at the apex.

Antagonistic bacterium strain TG26 secreting large amount of antifungal proteins was identified to be Bacillus subtilis by its cell morphological, physiological and biochemical characters. One of the antifungal proteins from TG26 strain was separated by gel filtration on Sephadex G-150 column and further purified with Mono Q column on FPLC. The purified protein with a molecular weight of 14.5 kD and a isoelectric point of 5.58 inhibits strongly mycelial spread of many kinds of plant pathogens. A amino acid analysis of the protein BI showed that glut aminic acid was the most abundant amino acid. No arginine, histidine, phenylalanine and tryptophane were found. The partial sequence of N-terminal was determined by Edman degradation.

A new flavonol glucoside, named yixingensin, was isolated from the aerial parts of Gy-nostemma yixingense C. Y. Wu et S. K. Chen. besides six known compounds. By means of spectroscopic analysis, the structure of yixingensin was identified as ombuin-3-O-β-D-glu-copyranoside ( Ⅰ ) . The known compounds were identified as kaempferol ( Ⅱ ), ombuin ( Ⅲ ), ombuoside ( Ⅳ ), quercetin ( Ⅴ ), isorhamnetin ( Ⅵ ) and stearie acid (Ⅶ).

Two polysaccharides, coded UV-2 and UV-3, have been isolated by boiling water extraction from Umbilicaria vellea (L.) Ach., fractionally precipitated by 60% and 90% EtOH, and isolated through DEAE-cellulose column chromatography. They are homoge-neous as judged by ultracentrifuge and filtration on sepharose 6B. By means of analysis of sugar component. periodate oxidation, Smith degradation and methylation, UV-2 and UV-3 were shown to be two highly brenched heteroglycans with few acetyl residues. The main chain of UV-2 is composed of β (1→3) linked glucose and mannose residues, but the main chain of UV-3 is composed of β (1→3) (1→4) linked glucosed residues. The results of pharmacological tests showed that activity inhibiting implanted S-180 in mice could not be found in UV-2, but UV-2 was able to significantly Stimulate phagocytosis of peritoneal macrophages and lymphocyte transformation.

The authors have established a simplified mechanistic model of spring wheat carbon assimilation and dry matter accumulation processes in which two independent variables, were considered as daylength and total daily radiation integral. This leaf water potential, an indicator of water limitation on spring wheat was incoorperated into the simplified mechanistic growth model assuming that both the light consuming efficiency and the carboxylation conductance of assimilation were inhibited by water limitation. The simulated data were well agreed with the data observed at Linze Oasis in 1989 for various water treatments and at Zhangye Oasis in 1992 in field. The analysis and simulation of the model demonstrated that the simplified mechanistic growth model could describe very well the dry matter accumulation process of spring wheat with or without water limitation.

With electron microscopy, the authors have observed the ER activities during the tapeturn development in Forsythia suspensa (Thunb.) Vahl as following: 1. It produces pro-U-bisch bodies at the meiotic stage of microspore mother cell; 2. It surrounds the proplastid and partakes the activity of lipid accumulation inside the plastids; 3. It secrets sporopollenin and 4. The rough ER inflats twice, surrounds and seperates the cytoplasm apart, forming the ER pocket and spherical bodies, which contribute to the thickenintg of tapetal cell walls and the secretion of exine protein.

Testosterone, a steroidal sex hormone, was determined in petal, anther, pistil and pollen of Lilium davidii, using a highly sensitive and specific enzyme linked immunosotvent assay (ELISA), and found to be present at levels of ng/g dry wt. In anther of lily, the level of testosterone increased during anther development, reached maximum at anthesis. After pollen shedding, testosterone rapidly decreased. No obvious changes of testosterone were observed with development of pistil and petal.Lily expresses gametophytic self-incompatibility. The levels of testosterone showed little difference in pistil, either after bud pollination, or self pollination. After hydration, the contents of testosterone in pollen slightly decreased. It rapidly decreased in pollen tube during germination at the first 3 h, but very little amount was found in germination medium. These results suggest that testosterone is associated with development and ripening of male gametophyte and pollen germination, but no sign indicates its participation in the process of self-incompatibility.

To elucidate genetic background of photoinhibition (PⅠ) in Indica-Japonica F1 hybrid rice (Oryza sativa L. ), reciprocal crosses were made among Indica rice 3037, Palghar, Minghui 75, NJ 11, Luweidao and Japonica rice 02428, LH 422, 029, YS 8072. Apparent photosynthesis, PS Ⅱ activity, binding amount of 14C-atrazine to thylakoid were determined as parameters for seeking the genetic nature of the photoinhibition revealed by the parents and Fl hybrids. The results suggested that Indica cultivars with few exceptions were usually more sensitive than Japonica cultivars. Degree of PⅠ in reciprocal Fl hybrids was much biased toward the value of their maternal cultivars, indicating a maternal inheritance which involved in the PSbA encoded D1 protein known to be related to the photoinhibitory PS Ⅱ damage and repairing. The sensitivity of photoinhibitory damage was also related to superoxide dismutase (SOD), an active oxygen scavenging enzyme encoded by the nuclear gene. Meanwhile, comparison of photoinhibition between Indica-Japonica Fl hybrid “3037/ 02428” and Indica Fl hybrid “Shanyou 63”, It was found that Indica-Japonica Fl hybrid appears to be a cultivar with tolerance of photoinhibition and more stable photosynthesis under photoinhibitory condition and weak-strong light shift in terms of above parameters. It was emphasized that photoinhibition of Indica-Japonica Fl hybrids usually varied depending upon the female mainly in the rice breeding .

A teleonomic model has been established which describes photoassimilate partitioning among plant organs during vegetative stage. Under circumstance of daily photosynthesis supply, linking the transpiration rate per unit of leaf dry weight (U) with water absorption rate per unit of water-absorbing root dry weight (V), using the function equilibrium among plant parts as the constraint conditions, the authors can obtain under-ground portions, influence of environmental factors on partitioning among plant organs. Likewise the authors explain how the plant adjusts it into a new state of function equilibrium under agricultural managments such as irrigation and pruning. Finally, the authors use the data published by Nagarajah (1983) to validate the model and it proves to be rather well. The anthors predict the photoassimilate partition by predicting U and V under environmental conditions. However it still awaits evaluation of its more extensive applicability.

SDS polyacrylamide gel electrophoresis was employed to examine the soluble protein composition of embryogenic callus, non-embryogenic callus, as well as developing embryoids in Panax quinquefolius L., Freesia refracta Klatt., Oxytropis leptophylla L. and Medicago suaveolens L. The results showed that embryogenic proteins were specifically present in potentially embryogenic calluses in all the 4 plant species studied. In Panax quinquefolius and Oxytropis leptophylla , the same embryogenic proteins were detected in developing embryoids. Besides a number of callus-specfic proteins was also found in non-embryogenic calluses of Freesia refracta and Medicago suaveolens. Although diverse in number, molecular weight and life span in different species, these specfic proteins seem to be related to the embryogenic state of callus, and may be used as markers to identify potentially embryogenic cultures and to trace the development of embryoids. They also provide the basis for studies of gene activities and molecular mechanisms of somatic embryogenesis in these plant species.

During the haustorial development of Cassytha filiformis L., the acid phosphatase and cytokinin (CTK) contents show dynamic changes in the cells. When haustoria are developed the isopenlenyl adenine (iPA) and zeatin nucleotide (ZR) contents are 20 and 6 times respectively higher in the region than that in the control region showing the occurrence of haustorial primordium in relation to the increase of CTK content. Acid phosphatase is firstly released from the cells of the penetrating haustoria and causes injury to the host cells. As the haustoria grow, they further squeeze the host cells. Therefore, the penetration and development of haustoria are the results of both physical and chemical actions.