February 1984, Volume 26 Issue 2


          Research Articles
Investigation on the Procaryotic Microfossils from the Gaoyuzhuang Formation, Jixian, North China
Author: Xu Zhao-liang
Journal of Integrative Plant Biology 1984 26(2)
    Stromatolitic cherts of the late Precambrian Gaoyuzhuang Formation at the Stratotype section of the ※Sinian Suberathem§ near Jixian, North China, contain a varied assemblage of well-preserved filamentous and coccoid blue-green algae. This assemblage constitutes perhaps one of the well-preserved, diverse Precambrian microbiota now known. The fossiliferous cherts occur in the lower part of this formation which is about 1500 Ma-old interpolated depending on Pb-Pb ages yielded from the middle part of it and K-Ar ages yielded from the underlying Dahongyu Formation. Fifteen new taxa of microfossils, comprising 6 new genera, are here described from the Gaoyuzhuang stromatolitic cherts. All species of blue-green algae have been recognized in the assemblage and refer to the modern Chroococcaceae, OsciUatoriaceae, Nostocaceae and Rivullariaceae. Most of these fossil algae are comparable in morphological details particularly to living Cyanophyta. It is evident that the cyanophytes had become well-diversified already by the late Precambrian. This evidence indicates that at least the morphological details are similar to those exhibited in living cyanophytes and these blue-green algae have not changed since Gaoyuzhuang time. This apparent evolutionary conservatism is probably attributable to a wide ecological tolerance and flexibility and also reflects its inherent genetic stability. The plant phylogenesis especially of Cyanophyta is discussed in this paper according to microfossil records detected in the thin sections of stromatolitic cherts from the Gaoyuzhuang Formation. Based on morphological characteristics and their generations Rivullariaceae may originate from Oscillatoriaceae. In addition algal biocoenoses in this stromatolitic chert grew in the form of laminar mats in the apparently subtital to intertital environment. The paleoclimate was subtropical or tropical. The following new taxa are here described:Microcystopsis yaoi, Eoaphanothece zhuiana, Oscillatoriopsis acuminata, O. hemisphaerica, O. disciformis, O. glabra, O. tuberculata, Eophormidium liangii, E. capitatum, E. semicirculare, Schizothropsis caudata, Paleoisocystis monosporata, P. disporata, Anabaenidium sophoroides and Paleocalothrix xui.
Abstract (Browse 1970)  |  Full Text PDF       
The Content Levels of Chemical Elements of Plants in the Castanozems Typical Steppe Zone of Nei Monggol
Author: Chen Zuo-zhong, Huang De-hua and Zhang Hong-fang
Journal of Integrative Plant Biology 1984 26(2)
    The contents of N, P, K, Ca, S, Fe, Al, Si, Na, of 122 plant species in the XiLin River valley in Nei Monggol were studied. These results have shown as follows: 1. The contents of N, P. K, Ca, S, Fe, Al, Si, Na of 122 plants belong to three levels: N, K, Ca are 101-100(%) P, S, Si, Na are 100-10-1(%); Fe, A1 are 10-1-10-2(%). 2. The contents of chemical elements of 122 plants were divided into three levels (high, middle and low content). The range of the content and the number of plants in each level were obtained.
Abstract (Browse 2002)  |  Full Text PDF       
Application of Numerical Classification to Study the Grazing Retrogressive Succession Stages of the Kobresia Vegetation on the Subalpine Meadow
Author: Li Shou-qian, Chen Sai-lin and Zhang Zhong-kui
Journal of Integrative Plant Biology 1984 26(2)
    Using the nearest-neighbour method in the course of numerical classification the four stages of the grazing retrogressive succession .of the Kobresia vegetation in Maqu Xian are divided: Ligularia virgaurea +Stipa aliena -Saussurea sp community and Leontopodium sp-Saussurea superba f. Pygmaea community belongs to the RSS (Retrogressive Succession Stages) of the grazing extremely; Anemone rivularis var fioreminore-Ligularia virgaurea-Kobresia spp community belongs to the RSS of the grazing seriously; Brachy-podium sylvaticum var gracile-Kobresia spp, Kobresia spp-Polygonum viviparum-Festuca rubra and Kobresia spp-Blysmus sinocompressus -Potentilla anserina communities belong to the RSS of the grazing moderately; Kobresia spp-Trollius farrei community belongs to the RSS of the grazing properly. Such classification method gives the same result as the traditional classificational methods of the RSS do. But it gives the numerical bases.
Abstract (Browse 1966)  |  Full Text PDF       
Studies on Sophora alopecuroides Gum
Author: Huang Qi-hua, Gao Wen-shu Fan Ming-juan, Shi Wan-yang, Wang Wei-tong, Yu Hai-ni and Sha Yi-xian
Journal of Integrative Plant Biology 1984 26(2)
    The seeds of Sophora alopecuroides L, contained 12.8 per cent of endosperm, from which the water-soluble polysaccharide gum was isolated and purified by fractionation with alcohol three times. Hydrolysis of the polysacchatides with sulphuric acid produced galactose and mannose in the molar ratio of 1:2.37, as determined by the phenolsulphuric acid method and by paper chromatographic method. The total sugar content reached 67-70%. The polysaccharides, after complete hydrolysis, reduction with NaBH4 and acetylation, ridded acetates. An analysis on them by gas-chromatography showed that they contained galactose and mannose in the molar ratio of 1:1.83, and the total sugar content reached 56%. In order to identify the linkages of the polysaccharides isolated from the seeds of Sophora alopecuroides, they were methylated by using the methods of Hokomori, Conval and Albersheim. The fully methylated polysaccharides were hydrolyzed and then reduced with NaBH4, followed by acetylation. Finally they yielded acetates. An analysis on IR data, the results of acid hydrolysis, periodate oxidation and Smith type degradation, as well as the acetates by GC, GC-MS and 1HNMR showed that the linkages of Sophora alopecuroides. gum may be, The purified polysaccharides seem to be homogenous after ultracentrifugation analysis. The sedimentation coefficient of the gum obtained from repeated purification with alcohol was 5.31, its intrinsic viscosity was 6.25 dl/g and its molecular weight was estimated to be 635000. By the light-scattering method, however, its molecular weight was estimated to be 715000. The crude polysacchafides contained 44 per cent of the water-soluble polysaccharides.
Abstract (Browse 2051)  |  Full Text PDF       
Studies on the Constituents of Murraya paniculata (L.) jack Grown in Yunnan
Author: Yang Jun-shan and Du Ming-hui
Journal of Integrative Plant Biology 1984 26(2)
    Two flavonoids were isolated from the leaves of Murraya paniculata (L.) Jack. (Rutaceae) grown in Yunnan. On the basis of spectroscopy (UV, IR, NMR and MS) analysis compound A and B were identified as 3,3∩,4∩,5,5∩,7, 8-heptamethoxyflavone (i), 3∩, 4∩ 5, 5∩, 7, 8-hexamethoxyflavone (j), respectively. The latter, named bannamu- rpanisin, is new natural product. In addition, three known coumarins, meranzin hydrate (k), murragatin (l) and murpanidin (m) were obtained.
Abstract (Browse 2361)  |  Full Text PDF       
Studies on the Chlorophyll,protein Complexes and Polypeptides of Chloroplast Membrane of Cator Bean
Author: Chu Zhong-xi, Xu Chun-hui, Wang Ke-bin, Mao Da-zhang, Zhao Fu-hong and Dai Yun-ling
Journal of Integrative Plant Biology 1984 26(2)
    The chlorophyll protien complexes separated from several plants were resolved by SDS-PAGE. It showed that the percentage (18%) of complex l in total amount of chlorophyll of castor bean (Ricinus communis L.) was obviously higher than that ( 13% ) of snake gourd (Luffa cylindrka (L.) Roem) and the percentage (41%) of LHCP complex in total amount of chlorophyll of castor bean was lower than that (48%) of snake gourd. The light-induced variable fluorescence change of castor bean (Fv/Fo=2.6) was much higher than that of snake gourd (Fv/Fo = 1.08) and other plants. The photochemical activities of chloroplasts of castor bean were very high. Its oxygen evolution activity (H20 ↙ DMBQ) was 575 米 moles O2﹞mg-1Chl﹞h-1, and the oxygen absorbtion activity of PSi (DCIPH2 ↙ WV) was 1274米 moles O2﹞mg-1Chl﹞h-1, the Chl/P700 ratio was 373, but those of snake gourd were 210, 148 and 751 respectively. There were distinct difference between the polypeptide pattern of castor bean and those of other plants. It was observed that 43, 47 KD polypeptide bands (polypeptides of PSj) of castor bean were darker than those of other plants. From the results mentioned above, it was considered that the high photochemical activities possessed by castor bean chloroplasts were partly due to its small photosynthetic units, e.g. its LHCP/RCCHL ratio yas smaller than those of other plants.
Abstract (Browse 1910)  |  Full Text PDF       
A Preliminary Study on the Chemical Constituents of Head Space of Jasminum sambac (L.) Alt
Author: Zhu Liang-feng, Lu Bi-yao and Luo You-jiao
Journal of Integrative Plant Biology 1984 26(2)
    The flowers of Jasminum sambac (L.) Ait. are noted for their fresh and delicate pleasant fragrance. We used the XAD-4 (Robin and Haas Co.) hydrophobic resin to absorb the fragrance released from the flowers and had a satisfied result. The Head Space was analysed by means of capillary GC/MS/DS combination and 37 constituents were identified. They are ethyl acetate (0.22%), 3-methyl cyclopentene (0.13%), 2-methyl hexane ( 0.09 % ), 2, 2, 3, 4-tetramethyl petane (0.07 % ), n-heptane (0.03 % ), phenyl- 2-propanone (0.05%), 2-methyl butate (0.03 % ), 3-methyl heptane (0.02%), butyl acetate (0.12 % ), 2-methyl propen-2-1y acetate (0.04 % ), n-hexen-l-ol ( 1.06% ), 6-methyl-2-hepta- none (0.18%), 6-methyl 5-hepten-2-one (0.12%), carbamyl benzoate (0.42%), 汕-pinene ( 0.53 % ), 3- hexenyl acetate ( 13.80 % ), limonene ( 0.12 % ), benzaldehyde ( 1.13 % ), ocimene ( 0.06 % ), methyl benzoate ( 6.27 % ), linalool ( 25.01% ), trans-linalool oxide ( 0.32 % ), benzyl acetate (23.71%), 3-hexenyl butate ( 1.72% ), methyl salicylate (2.55%), cyclohexyl formate (0.10%), indole ( 1.83% ), 2, 6-dimethyl 5-heptenal (0.05%), methyl anthranilate (1.56%), 2, 6-dimethyl heptenal (0.53%), 汕-caryophyllene (0.32%), 汕-farnsene (0.10%), humulene ( 0.21% ), 污 -cadinene (0.62%), cis-caryophyllene ( 13.67% ), trans, trans-farnsol (0.35%), cyclohexyl benzoate ( 3.37% ), respectively.
Abstract (Browse 3250)  |  Full Text PDF       
Protective Effect of Pretreatment of Spinach Chloroplasts with Mg2+ Against Trypsin
Author: Zhang Zheng-dong, Ma Gui-zhi, Li Liang-bi, zhai Xiao-jing and Zhou Pei-zhen
Journal of Integrative Plant Biology 1984 26(2)
    It has been shown that fluorescence yield of chloroplasts at wavelength near 684 nm can be regulated by Mg+2. But on the other hand trypsin abolishes this Mg+2-induced fluorescence change. Pretreatment of chloroplasts with Mg+2 protects the Mg+2 induced chlorophyll a fluorescence change from trypsin. It is found that the protective effect of Mg+2 pretreatment of chloroplasts against trypsin is concentration dependent (at the range btween 1.5-12 mM Mg+2). At a 12 mM MgCl2 concentration it appears that trypsin has no effect on Mg+2-induced fluorescence change. Similar results were obtained with the determination of chlorophyll contents in the chloroplasts. Plants grown at different temperature produce chloroplasts which show similar characteristics. But lower fluorescence and chlorophyll change are found in the Low temperature grown plants. The above results support the evidence that pretreating the chloroplasts with Mg+2 causes a conformafional change in LHCPs and protecting the functional group that acts as regulator to the fluorescence change against trypsin. It is also proposed that pretreatment of chloroplasts with Mg+2 also protects the connection of chlorophyll molecule with protein against trypsin in thylakoid membrane.
Abstract (Browse 1923)  |  Full Text PDF       
Auxin and Kinetin Induced Changes of Callus Cell Wall Composition of Abutilon avicennae Gaertn
Author: Wei Yu-ning and Guo Ji-fang Kuo Chi-fang
Journal of Integrative Plant Biology 1984 26(2)
    In a previous report we have shown that the arrangement of callus cell wail fibrils of Abutilon avicennae could be induced to change under IAA (2 ppm) and kinetin (10 ppm) treatments. Kinetin at this concentration was shown to be able to induce callus cell differentiation and form tracheary elements by changing the orientation of the wall fibrils. It was thus assumed that the hormonal induction of cellular differentiation and structual change of the cell wall may possibly be accompanied by the simultaneous changes of chemical composition of the wall. Attempt was therefore made to investigate if such changes do occur in vitro under the influence of phytohormones. Suspension cell-culture of Abutilon avicennae was used in this experiment to study the hormonal effect on the incorporation of H3-glucose into the cell wall polysaccharides. Analysis of neutral sugars of the cell wall following IAA (2ppm) and kinetin (10ppm) treatments was carried out with a gas chromatography. The results obtained in this experiment are shown in tables 1-2 and figures 1, It was found that the auxin was capable of promoting the synthesis of all neutral sugars, among which the glucose and the maunose in particular, increased tremendously. When H3-glucose was added to the culture medium, IAA was found to enhance the incorporation of the isotopes into the matrix polysaccharides (hemiceUulose and pectin). The result demonstrates clearly that the primary function of IAA is to stimulate the synthesis of hemicellulose composition and, as a consequence, the cell wall retained at the primary growth stage. Kinetin, on the other hand, showed an inhibitory effect on most of the neutral sugars except glucose and mannose. It appeared to have a striking inhibitory action on the synthesis of arabinose and rhanmose (a special composition of pectic substance). It also limited the incorporation of H3-glucose into the pectic substance. It is, therefore, suggested that the action of kinetin may mainly be inhibitory on the synthesis of pectic composition. The decreased rate of pectin synthesis would implicate that the cell wall has been advan ced into the phase of secondary growth. The results presented here agree fairly well with our connotation that there is a parallel relationship between cellular morphology and biochemical characteristics during cell wall differentiation and growth.
Abstract (Browse 2063)  |  Full Text PDF       
Effects of Physical and Chemical Factors on Induction Frequency of the Pollen Plantlet and Changes in Starch Formation in Anthers
Author: Gu Shu-rong, Gui Yao-lin and Xu Ting-yu
Journal of Integrative Plant Biology 1984 26(2)
    Physical and chemical facttors affected distinctly induction frequency of the pollen plantlets from anther culture in vitro of Lycium. Experimental results showed that the anthers with their pollen grains at the uninucleate stage when the nuclei were centrally situated, were the best material for the anther culture. The different proportions of various hormones have affected the embryoid formation. When the MS medium was supplemented with 6-BAP (1 ppm) and NAA (0.1 ppm), the induction frequency was increased ( 16.9% ). When 3每15 per cent of sucrose was added in medium, the embryoids were induced and 15 per cent was the optimum. The callus of the filament was inhibited by the increase of the sucrose concentration. Before inoculation the anthers were pretreated at 3每5⊥ for 4 days, the frequency of embryoid formation was efficiently increased in comparision with those of untreated anthers. The induction frequency of normal anthers was only 2.8 per cent, but that of the anthers pretreated was 3每9 per cent, the highest was 8.9 per cent .The changes of substances in anther pretreated and in normal anther was compared by means of histochemistry. Under normal conditions, there were a lot of starch accumulated in the inner wall Of the anthers and the distribution of the cytoplasm and the staining of the protein were even: In the anther pretreated, the starch grains have disappeared and the cytoplasm has condensed and the staining of the protein wasn't even. The differences may be related to induction, frequency of the anther culture.
Abstract (Browse 1939)  |  Full Text PDF       
A Preliminary Observation on B-Chromosomes of Regal lily
Author: Li Mao-xue, Long Ya-yi and Gong Wei-zhong
Journal of Integrative Plant Biology 1984 26(2)
    The authors have observed t he karyotypes of the Regal Lily with B-chromosome and without B-chromosomes as well as their Giemsa C-bands. The results show that the karyotypes with B-chromosomes are not obviously different from those without B- chromosomes. B-chromosome is additional and all of them are heterochromatization. But segregation of B-chromosome at anaphase i and j in meiosis is irregular, and about half of the pollen grains contain B-chromosomes. In the progenies by open pollination the segre, gation of 0B and lB appear in the ratio near 1:1 and the offsprings with 2B-chromosomes only average 2.6 percent.
Abstract (Browse 1939)  |  Full Text PDF       
Anatomical Studies on Secondary Phloem of Pinus bungeana
Author: Zhang Zhen-jue and Gao Xin-zeng
Journal of Integrative Plant Biology 1984 26(2)
    This paper deals with structures of the secondary phloem of Pinus bungeana Zucc. The sieve cells lived for only one growing season. Most of them formed in spring and summer and then died in the end of winter. However, some of them formed in autumn and died eventually in the end of next spring. Two types of albuminous cells: type A and type B were seen in radial plates and rays, which possessed the following common characteristics, there were unilateral sieve area connections between these and the sieve cells. These cells had larger nuclei, denser cytoplasm with abundant mitochondria and rich RNA-protein. Their death closely followed that of the sieve cells. Type A albuminous cells differed from type B in that the former collapsed before the contents of sieve cells accompanied with it dissppeared. But, type B did not collapse until complete disappearance of the contents of sieve cells. The cytological characteristics of albuminous cells, the relationship between radial plates and rays, and possible physiological significance are also disscussed.
Abstract (Browse 1782)  |  Full Text PDF       
The Fine Structure of Melosira arenaria Moore
Author: Huang Cheng-yan
Journal of Integrative Plant Biology 1984 26(2)
    Micro-structures of the valve, girdle and old valve jacket of Melosira arenaria Moore collected from the mudstone beds of Shanwang formation in Shanwang village, Linqu Xian, Shandong Province, PRC., have been observed under the optical microscope and SEM. The author found that the ornamentation of this diatom is quite similar on the girdie of different frustules, but rather variable on their valves. These variable structure can be classified into three types: 1. long striate type; 2. short striate type; 3, long wedge-shaped type. Furthermore, the fundamental structures of M. arenaria are very similar to that of M. teres, M. sol, and M. polaris. Thus we may consider that they are affinities in the phylogeny of algae.
Abstract (Browse 1961)  |  Full Text PDF       
Studies on the Micronuclei Induced by Irradiation in Vicia faba
Author: Guo Bao-jiang and Li Shu-xian
Journal of Integrative Plant Biology 1984 26(2)
    In this experiment ,the remits of observing under the light microscope and electron microscope, and statistical analysis showed that micronucleus had a certain shape and structure. There was a linear correlation between the micronudeated cell frequency and dosage or the chromosomal aberration frequency in the root tip cells. The micronudeated cell frequency changed according to the different periods of time after irradiation. At the same time, micronuclei that might be synchronous, or not, with the main nucleus for the cell cycle were seen. That means it is possible for some micronuclei induced by irradiation to carry on division. Therefore, the advantages of micronucleus test lies not only in simply and effectively evaluating radiation damage to cells but also in exploring the mechanism of radiation genetics in plant.
Abstract (Browse 1997)  |  Full Text PDF       
A Study of Pollen Morphology of Sparganium from China
Author: Zhang Yu-long and Chen Yao-dong
Journal of Integrative Plant Biology 1984 26(2)
    Pollen morphology of 8 species in genus Sparganium from China has been studied. All of them were examined under the light microscope and SEM. It may draw the following conclusions: The characteristics of pollen grains in genus Sparganium are very similar. They are spheroidal, subspheroidal or sometimes slightly angular in shape, 21.8每38.3米m in diameter, monoporate. Porus is slightly sunken, its margin distinct or indistinct, and some granules on the porus membrane. The thickness of exine is 1.7每2.6米 m. The sexine is about as thick as nexine, sometimes thinner than nexine. It is difficult to distinguish one another under the light microscope, but may be seperated under SEM on the basis of the shape or size of lumina and width or height of muff. In some species small excrescenses can be observed under SEM. Some taxonomists (Rendle, 1953) considered that Sparganium is closely related to Pandanus, but others (Hutchison 1934, Takhtajan 1969) to Typha. According to the data of pollen morphology, Sparganium is more close to Typhaceae than to Pandanaceae, thus we agree to put it into family Typhaceae.
Abstract (Browse 2201)  |  Full Text PDF       
The Protein Body in Dedifferentiating Cels of Tobacco Leaf Explants
Author: Zhu Zhi-qing Chu Chih-ching, Sun Jing-san Sun Ching-san, Li Shou-quan and Zhu Ying-min
Journal of Integrative Plant Biology 1984 26(2)
    Light and electron microscopic observations show that a kind of spherical electron-dense body appears in the dediffercntiating mesophyll cells and their subdivided cells in tobacco leaf explants cultured for more than two days. The larger electron-dense bodies (1.0每1.5米m in diameter) present in vacuoles while the smaller ones (0.1每0.8 m in diameter) in cytoplasm. This implies that the bodies first can be formed in cytoplasm and then secreted into vacuoles. Since the bodies can be fixed with glutaradehyde and 3H- leucine can incorporated into them, they may be recognized as protein bodies. The protein bodies usually closly combined with newly formed cytoplasmic masses so we suggest that they probably play some role in cytoplasmic growth of dedifferentiafing ceils.
Abstract (Browse 1796)  |  Full Text PDF       
Organogenesis of Lear Explants of Momordica grosvenori Swingle In Vitro
Author: Gui Yao-lin, Gu Shu-yong and Xu Ting-yu
Journal of Integrative Plant Biology 1984 26(2)
    Leaves of Momordica grosvenori Swingle were used as experimatal material. Plantlets were obtained on MS medium supplemented with 6-BA 1 ppm and IBA 0.5 ppm. Histocytological observations on adventitious bud formation were carried out. After 1 week in culture, mesophyll cells obviously enlarged, cell divisions began in the mesophyll cells near the cut ends of explants, and meristemoids which consisted of small dark stained cells without chloroplasts were produced. Then meristemoids continued to proliferate and redifferentiated into many leaf-shaped bodies. Three weeks after cultivation, adiventitious buds were produced from meristemoids at surface layer of leaf-shaped body. The stem of plantlet was cut off when it reached 2 cm in height, and then was transferred onto MS basic medium supplemented with NAA 0.25每0.5 ppm for rooting. About 10 days after cultivation, vigorous root system was produced from the cut end of plantlets. It is possible that this technique of obtaining whole plants by leaf explant culture provides a method for the multiplication of the good individual plants of M. grosvenori.
Abstract (Browse 2253)  |  Full Text PDF       
An Autoradiographic Study of the Azolla-Anabaena azollae Relationship
Author: Sun Jing- san,Sun Ching-san, Chen Wei-lun, Zhu Zhi-qing, Chu Chih-ching and Zhu Ying-min
Journal of Integrative Plant Biology 1984 26(2)
    The symbiotic relationships between Azolla and Anabaena azollae were studied by means of autoradiography after the Azolla was administered by 3H-thymidine, 3H-uridine, 3H-leucine and 3H-glucose. The experimental results showed that the four labeled compounds mentioned above were transfered from Azolla to Anabaena azollae through cavity hairs. This indicated that there was a transfer way of substances from fern to algae. It is suggested that the symbiotic relationship between Azolla and Anabaena azollae is more complicated than we have known up to now. The fern not only get the NH3 which was formed by symbiont-blue alga, but also supplied some nitrogen-containing substances, such as amino acids (or proteins), ribonucleotides for symbiotic algae. Although the symbiont still retained photosynthetic ability, the ability of nitrogen fixation might be developed and the photosynthetic autotrophic ability might be dropped gradually in the long symbiotic life and the Anabaena azolla needed take a portion of substances from the Azolla as replenishment.
Abstract (Browse 1935)  |  Full Text PDF       
The Fossil Plants from the Upper Part of the Wutong Formation in Chaoxian District, Anhui Province
Author: Li Han-min and Lan Shan-xian
Journal of Integrative Plant Biology 1984 26(2)
Abstract (Browse 1881)  |  Full Text PDF       
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