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1989  Vol. 7  No. 3

Abstract:
The stolon arises at the second or third leaf axil from the apex. During development of a stolon, cell divisions occurred orderly alongthe basal and lateral limits of the incipient stolon primordium, forming a zone of parallel curving layers referred to as the shell zone. The stolon primordium appears to be associated with an active outward growth by the shell zone.The tunica of the stolon apex is uaually one layered. Thickening and elongation of stolon are manifested mainly by expansion and axil elongation of the cells.In the process of corm formation, figures of mitotic nuclear divisions appear in the cells of the ground tissue at several nodes of the stolon near its apex and cell expansion occurs afterwards. Simple starch grains are stored in the corm in general, but both simple and compound starch grains are formed in the stolon.
Abstract:
The present paper reports the karyotype of Fritillaria huangshanensis Y. K. Yang et C. J. Wu and F. monantha Migo. The former was collected from Jiaugxi, its karyotype fomula in 2n=24=2m+2sm+6st(4sc)+14t. The latter was collected from Zhejiang, its karyotype formula is 2n=24=2m+2sm+6st(4sc)+14t(2sc). The karyotypes of two species were studied for the first time.F. huangshanensis, F. monantha, F. thunbergii, F. anhuiensis and F. hupehensis native to middle and lower reaches of the Changjiang River, have highly similar karyotypical characteristic. The 5 species comparing with F. olgae, F. verticillata, F. yuminensis, F. walujewii and F. pallidiflora native to Xinjiang Northwest China, the karyotype asymmetrical degree of them has increased, the number of secondary constrictions has decreased (from 8—16 reduce to 2—6 ), and the secondary constrictions is only found on the long arms. According to the karyotype analysis, they are a group of evolutionarier population than that of from Xinjiang.
Abstract:
The chromosome numbers of five species of precious rare and endangered plants are reported as follows:1. Amygdalus mongolia (Maxim) Yu 2n=16; 2. Kolkwitzia amabilis Graebe 2n=32; 3. Magnolia amena Cheng 2n=38; 4. Davidia involucrata var. vilmoriniana (Dode) Wanger 2n=42; 5. Fritillaria ussuriensis Maxim 2n=22. Among them, chromosome numbers of M. amena, D. involcrata var. vilmoriniana are reported here for the first time. They are important genetic resources of China. The results will provide cytological information for their conservation, utilization and development.
Abstract:
A primary observation on the DNA, RNA, basic protein, acid protein and polysaccharide at the process of fertilization in the proembryo and early young embryo of Keteleeria evelyniana Mast has been made through histochemical methods. The following results are obtained:The DNA staining reaction was weaker by using Feulgen reation before and after fertilization within the egg nucleus. After formed proembryo and early young embryo, the content of DNA in the nuclei of the initials became normal. The RNA and acid protein contents are rich during the whole development, especially within the embryo initials. However, A-S staining of the basic protein was negative within the neocytoplasm, but the DNA, RNA, acid protein and polysaccharide were positive.
Abstract:
A comparative structure study of stem and underground stem between "gangchai" and "shachai" was carried on by us. At the same time, we observed the variation of fiber morphology in the ninth, fifth and second internodes of the stem respectively.The morphology and anatomy between "gangchai" and "shachai" are almost alike. The distribution of short cell on the epidermis of "gangchai" is little more, sometimes, they are get together into a colony. These categories are vice versa in "shachai". The density of short cell distribution on the upper, the most; the middle, the less; the lower, the least. In their cross sections, there is only one fiber layer inside of "gangchai" epidermis; but there are 2—3 fiber layers in "shachai". The "V" shaped vascular bundle is round or ellipsoidal in "gangchai" arranged into 5—6 wheels. The vessel number in its metaxylem is variable, the highest, 7—8; in general, 2—3. The vascular bundle of "shachai" is plate-rounded, arranged into 4—5 wheels The vessel number in its metaxylem is few, from two to three. There are several small vascular bundles differentiated inperfectly scattered in the center of pith on the upper internodes of stem. The structure of both stem and rhizome is almost the same.The fiber length of "gangchai" and "shachai" varies according to its possition on the stem, the longest, in the fifth internode; the shortest, in the ninth internode; the middle, in the second internode. But the length and the ratio of length to width in "gangchai" is larger one-third than that of "shachai". By the way, the stem of "gangchai" contains a few of non-fiber cell, its fiber quality and productivity in a unit area are better than those of "shachai" also.From the above analysis of morphology and anatomy, we believe that "gangchai" and "shachai" are probably originated from one species and this species has differentiated into two different varieties—"gangchai" and "shachai". In other words, we have to do some work about morphology and anatomy of their reproductive organ especialy about their cytology and embryology for the final identification.
Abstract:
The relationship between the leaf construction and the freezing hardiness of the species Magnoliaceae, Michelia martinii etc is that the number of stomata per area is negative to the freezing hardiness and the thickness of cuticle of the upper epidermis and the thickness of the palisade mesophyll is positive to the freezing hardiness.
Abstract:
The species of Alismataceae are chiefly distributed in Lichuau-Enshi-Hefeng-Jianshi, often grow in mountainous swamps and paddy fields mostly with rich humus and acidulous soil (pH value usualy below 7). The species number tends to increase as the altitude increases, yet the distributional amount is the greatest below 800m alt. Although some species have wide distribution, yet most species of this family have very narrow distribution, having fairly strict selection for the habitats, and all these are correlated to the distribution of mountainous swamps and paddy fields.Mainly distributed in subtropical and temperate East Asia, the flora of Alismataceae in southwestern Hubei has a very close relationship With the same flora in Jiangxi, Jiangsu and Japan.
Abstract:
Measuring a piece of leaf area in pear trees using regression equation method, it is suitable to use the regression equation of multiplying leaf length by the width, according to the methods of long-shoot sampling, random sampling and proportional sampling, and the leaf quantities being 50—100 pieces.
Abstract:
The comparetive studies of esterase and α-amylase isozymes on the bamhoo rhizome systems with different developmental ages, and standing culms in same rhizome with a series of growthages were made by means of polyacrylamide gel electrophoresis. The samples were from edible bamboo species for giant pandas in sub-mountain areas, including seedlings, full-grown and flowering bamboo plants. The results showed that the leaf EST can present various electrophoretic patterns for different rhizome systems of the same species. But the Shifts in AMY isozymes appear related to age level of bamboo culms. As a consequence it is suggested that two of above mentioned isozyme systems may be used as a physiological index for development analysis of bamboo clone.
Abstract:
The essential oils were extracted by steam distillation from fresh leaves of 3 species of Cinnamomum collected from west Hubei. 4 samples of essential oils, prepared respectively from different producing area, were examined qualitatively and quantitatively by the methods of capillary GC/MS/DS on Finnigan-4510 type. As the result, the major component of 3 samples is citral——the essential oil of C. wilsonii produced from Changyang County contains it 77.99%, the essential oil of C. wilsonii produced from Xianfeng County contains it 86.47% and the essential oil of C. bodinieri var. hupehanum contains it 95.01%. The major component of the essential oil of C. Camphora is 1,8-cineole (65.76%).
Abstract:
Investigations have indicated that germplasm resources in Camellia are very rich. The species have increased from 29 to 52, the characteristic species increased from 4 to 12, in which 3 new taxa and 1 variety have been discovered. The characteristics of fruits, oil content of seeds, physicchemical properties of fats and oils in 41 Camellia species have been analyzed. The results have shown that the oils and fats of Camellia are very rich in content, which have good quality, pollutionless excellent storage properties as well as higher economic value both in human daily life and machinery. Docosa-enoic acid discovered in fats and oils of Camellia plants is first reported in our paper.
Abstract:
The study is put emphasis on the equipment, fertilizer and nutrient solution, economic benefit of NFT. The tomato yield of early yield variety in NFT culture is 8361.1 kg per mu. The cost of tomato in one production season is 0.29 yuan per kg. The plants and roots in NFT are flourishing and bearing fruit is earlier. The tomato fruit are large and good quality. The study demonstrates easy manipulation, good yield and economic effects used NFT to culture the tomato and the cucumber.