In this paper, the shape and size modification of recent pollen grains have been studied. 63 species of recent pollen grains that belongs to 55 genera, 26 families were observed before and after the acetolysis treatment with LM. The length of polar axis and equatorial axis and the thickness of exine were measured from about 20 pollen grains for each species (the thickness of exine were only measured for acetolysed pollen grains). The significance of shape and size modification was examined with the statistical method "ttest". From this investigati0n it can be concluded that: The pollen modification in size and shape 'was related to aperture type, pollen size, wall thickness and sculpture depth. Pantoporate, spheroidal pollens and small perporlate pollens usually change little in there size and shape after acetolysis. The size of colpate pollens was generally increased, or their shape changed. The size or shape change usually got bigger as the pollen size, wall thickness and sculpture depth became bigger and bigger. Oblate pollens were apter to change their size and shape than prolate pollens. The P/E ratio of most colpate pollens became a little bigger after acetolysis.

Metasequoia is endemic to China. Present study deals with ultrastructure of pollen exine of M. glyptostroboides Hu et Cheng, and in comparision with other genera of the family. Pollen grains of Metasequoia are spheroidal or subsphoroidal and 27.8(24.3–32.3) μm in diameter. There is a papilla in the distal face. The papilla is wide at the base, 3.5–5.2 μm high, with pointed and circular end and the base crooked toward one side. Exine is about L5 μm thick, layers distinct, Nexine is as thick as sexine. Surface weakly granulate. According to observation by SEM, exine is covered with fine granules and rather coarse tuberculae. The former can be easily separated from the latter. The loose and uneven tuberculae are provided with minute spinules on the surface and generally fall off after acetolysis. The fine and dense granulae, however, remain intact after acetolysis. The study by TEM shows that ektexine is made of granules densely arranged and connected with each other. In addition, sparse Ubisch bodies are unevenly distributed on granular layer with geminate surface. The thick endexine, is composed of 10–15 lamellae. It is worthy to note that all lamellae possess tripartite structure. But lamellae of endexine in other genera of Taxodiaceae have no tripartite structure except the lamella near ektexine. Number of lamella and thickness of endexine in Metasequoia differ from those of other genera in Taxodiaceae; for example endexine with 8–10 lamellae in Taxodium, 8–9 lamellae in Sequoia, 6–7 lamellae in Glyptostrobus, 6–8 lamellae in Cunninghamia, about 16 lamellae in Cryptomeria etc.

The transpiration rate of Abies georgei (20 years) was determined at sample plots on subalpine in Northwest of Yunnan Province. The result of annual change shows that the rate is from lower to higher monthly. The transpiration rate reached maximum value of 195.88 mgH20·gdw-1·h-1 in July, then, it decreases gradually in a open-grown sample leaf of the current year. The phenomenon of “noon-rest” shows that the curve for day change of transpiration rate is the form of double peaks. Statistical analysis proves that the variance of transpiration rate is influenced mainly by the environmental factors, particularly by temperature, relative humidity and light intensity. The correlations between transpiration rate and temperature, light intensity are positive and that between transpiration rate and relative humidity is negative. The variances of the transpiration rate on the elevations are different. The transpiration rate decreases with the increase of elevation in the natural forest area. Change is less in whole day at high elevation and light wave too. The rate of transpiration in clear cut over area is higher than in the area under deep canopy of a subalpine natural forest, they are 186.15 and 123.97 respectively Lastly, the correlation between transpiration rate and environmental factors and plant setting are discussed in this paper.

Sinenofuranal and sinenofuranol, two new sesquiterpenoids were isolated from the essential oil of Aquilaria sinensis (Lour.) Gilg. by flash column chromatography (silica gel) and Sephadex-20 column chromatography Based on preparation, spectra of derivative sinenofuranic acid (Ⅶ), the analysis of X-ray diffraction and spectra of sinenofuranol (Ⅱ), the structures of two sesquiterpenoids were elucidated as (Ⅰ) and (Ⅱ) in Fig. respectively Baimuxinal, baimuxinic acid, β-agarofuran, dihydro karanone were also isolated.

The essential oil of leaves and the absolute from flower of Tagetes erecta were analysed by GC, GC/MS, IR, column chromatography. About 50 compounds in the essential oil have been identified, most of then are terpenone. 28 compounds in absolute have been identified. γ-, △-cadinene, cis-caryophyllene and other sesquiterpenes are major constituents in absolute The essential oil has good antibiotic activity and no irritability to human skin. It is a kind of useful natural fragrance.

The methods of GC with fused silica capillary column, its Kovats retention index of GC and GC-MS-DS etc. We were used to study the aromatic compounds of the peel essential oil of Citrus sinensis (L.) Osbeck and aromatic concentrates of fruit flesh. 29 chemical constituents from the peels and 40 chemical constituents from the fruit flesh were identified. The trace constituents α-sinensal 0.01% and β-sinensal 0.01% are the special aroma ones for Citrus sinensis. At the same time, the changes flavor components in Citrus sinensis peels and fruit flesh during storage were also explored.

The triglycerides of fats from several varieties of Sapium sebiferum (L.) Roxb. were determined by means of pancreatic lipase hydrolysis technigue. Triglycerides of the fats. are composed of 9–14 kinds of triglycerides. They are similar to Cocoa butter. Fatty acid composition in 2-position of glycerides is oleic acid in more than 82%. The disaturated glycerides account for 81-88%, in which POP is in the majority (74–81%); the proportion of monosaturated glycerides is 1.8–6.0%; the trisaturated glycerides hold 9.6–15.6%, in which the main one is PPP (8.5–14.0%). The fats can be used for making Cocoa butter substitute by proper processing. Fat contents of the four varieties (“Da Li Ji Zhao”, “Wu Gong”, “Tong Chui” and “Xiao Li Ji Zhao”) cultivated in Guangxi province are richer (32.0–34.3%) than that of the wild species of the same plant. The proportion of disaturated glycerides is the highest (88.0%) and that of trisaturated glycerides is the lowest (9.6%) in fat from "Da Li Ji Zhao".

The reversible hydrogenase in vegetative cells of A. variabilis cultured on NH4+ or N-free medium was induced by sparging with N2 for 24 hours under light. Both anaerobic condition and illumination appear to be necessary for the induction of hydrogenase in this algae. The properties of the hydrogenase in cell-free extract obtained from the cells grown on two nitrogen sources are similar: (1) Both the enzymes are able to evolve H2 in the presence of reduced methyl viotogen as electron donor, and to uptake H2 in the presence of benzyl viologen as electron acceptor. (2) The enzymes posses the thermal stability and are stable to O2. (3) The optimum pH required for H2 evolution activity of the enzymes is 7.0–7 5. (4) The Km of the enzymes obtained from NH4+ grown cells and N-free grown cells is 300 mmol/l and 295 mmol/l, respectively. So the high Km measured here suggests that the enzymes in both cases function physiologically as H2 evolution. (5) The activities of both enzymes are inhibited by CO but are not affected by C2H2. The induced H2 evolution activity of the reversible hydrogenase in cells grown on NH4+ reached 1530 nmol H2/mg dry wt, h, which was 3 to 5 times higher than from cells grown on N-free medium. Our experiment results indicate that the appearance of heterocysts of A. variabilis cultured on N-free medium affects the synthesis of reversible hydrogenase and the regulation of its activity.

Chilling (1 ℃ or 5℃, 16 h) treatment inhibited PSⅡ but not PSⅠ of photosynthesis in cucumber, a chilling sensitive plant. Oxygen evolution, variable fluorescence, and DCIP photoreduction were inhibited significantly, and the latter two could be recovered to the control level by adding artificial electron donors. These results suggest that chilling temperature damages PSⅡ of cucumber only on the oxidizing side and does not affect its reaction center.

The content of glucosinolates during anther culture of Brassica junces has been investigated. Experiment results expressed that the content of glucosinolates in pollen embyoids was high, then decreased with the growth and development of the embryoids, A ralative stability of the content was maintained from 30 to 50 days cultured. When the secondary embryoids came into being, the content increased rapidly. The myrosinase activity of every sample was determined at the same time. The results of determination showed that the pattern of the change of myrosinase activity was similar to the glucosinolate content.This indicates that there is a correlation between glycosinolate content and myrosinase activity.

In order to find cell strains with high and selective 12β-hydroxylation capacity, the relationship between the hydroxylation capacity of Digitalis lanata plants and cells in culture was studied. 80 different cell strains initiated from 36 plants with various Digoxin contents and hydroxylation were investigated, The results of these experiments Showed that there is no correlation between the hydroxylation capacity of plants and that of the cell cultures.

This paper emphatically deals with the ultrastructure of albuminous cells in different stages of development in the secondary phloem of Pinus bungeana. The secondary phloem of Pinus bungeana is composed of sieve cells, axial parenchyma cells, radial plates and rays. Among the constituents, most of upright ray cells and radial plate parenchyma cells are albuminous cells. Although the shape and distribution of this kind of albuminous cells may be different, they possess the following common cytological characteristics. These cells have dense cytoplasm with abundant mitochondria, ribosomes, rough endoplasmic reticula and a large nucleus, the nuclei of some albuminous cells are lobed in shape which increases the outer surface of the nuclei. Usually the albuminous cell contains some starch granules, the quantity of the starch granules in albuminous cells is less than the other parenchyma cells of the secondary phloem. All these cytological characteristics suggest that albuminous cells are active physiologically. The distinguishing characteristics of albuminous cells from other parenchyma ceils are that the albuminous cells are associated with sieve cells through unilateral sieve area and they died together with the sieve cells.

In trees, after removal of the bark, the vascular tissues of the newly-formed bark usually developed as a continuous layer. However, the stem of the herbaceous Jerusalem artichoke, after girdled, gives rise to regeneration of many irregularly arranged vascular bundles. Early July is the best time for girdling as the vascular bundles are well-developed, One week after girdling, some small groups of vascular tissues appeared in callus. Later on the vascular bundles eventually grew close together sooner or later, yet there were some wide pith rays which separated the various sized vascular bundles and exhibited irregularly contours. From these experiments, it is further evidenced that tile stem of herbaceous plants can also be girdled and regenerates a new rind. Furthermore, the girdled portion of this plant regenerates the vascular tissues which in a rather different way from all the plants that previously studied.

The observation by transmission and scanning electronic microscopy on the endosperm cells from mature and developing seeds of Sesbania cannabina shows that the Sesbania gum after its synthesis is not secreted out of cells, it is accumulated inside the cells. The viscosity determination of different size of granules demonstrates that, the larger the size of granules, dm lower the gum viscosity, on the contrary, the smaller the size, the higher the viscosity. This result is in agreement with the localization of gum inside the cells. In addition, the total Content of saccharide and insoluble substances for different size granules was also determined, These results provide the need of small size of gum granules in the process of production with tile evidence of gum localization inside the endosperm cells of Sesbania seeds.

Anemarrhena asphodeloides is a monotypic genus of Liliaceae, endemic to China and Korea. This genus is characterized by possessing three stamens. From development of male gametophyte, three features of the species are noteworthy. (1) During meiosis of the micros- pore mother cells, the Golgi vesicles are immediately incorporated into the formation of the material of callose wall; The latter lying at the outer tangential is about 4 gm in thickness dining formation of the tetrad. In the outer tangential callose wall there are certain cytoplasmic canals, which are about 0.6 to 1 μm in diameter. During the development of pollen grains, there are a number of other vesicles dispersing in the cytoplasm of the microspores. The activity of these vesicles seems to be involved in accumulation and formation of lipid bodies. But the above vesicles, which were derivxed from Golgi or endoplasmic reticulum, have not been known in this genus. (2) By two-celled stage of pollen grains, the unequal distribution of lipid bodies is very prominent, and they are singular in being placed on the boundary between the plasmalemma of vegetative and generative cells. While the generative cell is delached from the intine of pollen grain, the generative cell is surrounded by the lipid bodies which had been called the corona of them. By the observation of TEM, these lipid bodies come from the cytoplasm of vegetative cell and did not remain a constant surrounding layer. Towards the stage of pollen maturation, the lipid bodies lying oppositely to the nucleus of vegetative cell were gradually dispersed in the cytoplasm. Their function is unknown but the observation shows that some of them move to the plasmalemma of the pollen grain. (3) An important feature of the mature pollen grain in Anemarrhena is that the generative cell does not contain plastids during polle development. On the basis of cytological mechanisms of the plastid inheritance, Hagemann (1983) has classified the angiosperms into four groups of species, of which the Lycopersicum type, Solanum type, and Triticum type belong to the mode of a uniparental maternal inheritance of plastids; while the Pelargonium type represents the mode of biparental inheritance of plastids. Our studies have confirmed that the mode of plastid inheritance in Anemarrhena asphodeloides is similar to Gasteria verrucosa, both show the same mode of plastid inheritance of Lycopersicum type.

By using bioassays, some plant growth-regulating activities of matrine were determined. The results obtained indicated that matrine obviously increased both the fresh and the dry weight of isolated cucumber cotyledons. Matrine decreased the total chlorophyll content but stimulated the photosynthesis of isolated cucumber cotyledons cultured in light (5000 Ix, 26 ℃). Furthermore, the rooting of isolated cucumber cotyledons cultured in the dark (25 ℃) was markedly promoted by matrine. These phenomena showed that matrine had distinct plant growth-stimulating activites.

Cunninghamia asiatica (Krassilov) comb. nov. was an early Cretaceous plant which was widely distributed over North and North-East China and Siberia. It was previously identified as Elatocladus manchurica (Yak.) or Elatides asiatica (Yak.). Present paper combines them into Cunninghamia mainly based on the similarities of the morphological and epidermal characteristics between the fossil species and living Cunninghmia (table 1 and 2), and dates the history of Cunninghamia back to Early Cretaceous.