细裂银叶菊叶的组织培养繁殖研究

以细裂银叶菊叶片为材料,进行愈伤组织的诱导、分化培养及生根诱导培养。结果表明：叶片愈伤组织的诱导以MS 2,4-D2mgL^-1 BA1mgL^-1 NAA0．1mgL^-1。培养基较好：分化培养以MStBA0．5mgL^-1 NAA0．1mgL^-1为好：生根诱导以1／2MS NAA0．01mgL^-4效果最好。     

Selection of an atrazine-resistant tobacco cell line having a mutant psbA gene

Summary A mutant cell line that shows high resistance to the photosynthesis-inhibiting herbicide atrazine was selected from cultured photomixotrophic Nicotiana tabacum cv. Samsun NN cells by repeated exposure to toxic levels of the herbicide. This resistance was confirmed by measurements of Hill reaction activity in isolated thylakoid membranes. Nucleotide sequencing revealed that the resistant cell line had a point mutation in its chloroplast psbA gene. The 264th codon, AGT (serine) was changed to ACT (threonine) in this mutant. This new type of mutation also conferred moderate cross-resistance to diuron and subsequently was stable in the absence of continued selection pressure.     

Effect of heavy metals on isoperoxidases of Wheat

The influence of increasing concentrations of copper, zinc, lead, nickel, chromium and cadmium on 14-day-old seedlings of wheat (Triticum aestivum L. cv. Vergina) was studied. Plants were grown in 1/10 strength Rorison’s nutrient solution with increasing concentrations of each of the metals added separately. The toxicity of metals depressed shoot growth but the most evident symptoms were on roots. The concentration of each metal which caused inhibition of root growth was chosen to study the influence of metals on isoperoxidases of wheat shoots. The concentrations employed did not alter the number of peroxidase bands but almost in all cases enhanced the intensities of bands of pH 4.0-4.2 and 5.0-5.4, while they decreased the intensities of bands of pH 4.2-4.6 and 5.4-6.5. The similar effects of the different heavy metals employed may suggest similarity in metal action on wheat isoperoxidases. The increased intensities of peroxidase bands may be considered as an indication of enhanced senescence caused by the heavy metal treatments. Generally, our results suggest that the heavy metals employed have caused complex changes on the multiple forms of peroxidases.     

Enzymic changes in response to zinc nutrition

With a view to evaluating the suitability of Zn induced changes in enzyme activities and for assessing Zn nutrient status, black gram (Vigna mungo L. cv. IPU 94) was grown under controlled sand culture at five levels of Zn supply ranging from 0.01 to 10 μmol/L. Leaves of 60 d old plants were examined for Zn concentration and activities of fructose 1,6 biphosphate aldolase, carbonic anhydrase, total superoxide dismutase, Cu-Zn SOD, acid phosphatase and ribonuclease, which have been shown to be activated/inhibited by Zn deficiency. Sub-optimal supply of Zn decreased the activities of FBPAse, CA, total SOD and Cu-Zn SOD and increased the activities of APase and RNAse. Activities of the Zn enzymes CA and Cu-Zn SOD, are highly correlated with Zn supply, and suitable as indicators of Zn nutrient status of plants. Activation of APase and RNAse by other micronutrient deficiencies and stress conditions does not favour their use as indicators of Zn nutrient stress.     

3个香榧单株的种实性状变异分析

对浙江宁海3个香榧单株种实种长、种径、种长径比(种形系数)、单种重、鲜出核率、核长、核径、核长径比(核形指数)、单核重9个性状指标进行了测定和统计分析,为香榧优株选育提供理论依据。结果表明:单种重平均值最大的是宁榧1号(9.17 g),单种重极大值出现在宁榧1号(13.6 g);单核重平均值最大的为宁榧1号(2.93 g)。平均鲜出核率最大的是宁榧3号,达到40.86%,鲜出核率极大值出现在宁榧2号(51.06%)。株间种长、种径、种长径比、核长、核长径比、单种重、单核重、鲜出核率指标均存在显著差异,而核径差异性不显著。种实性状变异幅度最大的指标为单核重(变异系数CV为22.68%),单种重(变异系数CV为21.18%)次之,最小的为种长径比(变异系数CV为4.49%)。种长、种径、核长、核径均与单种重和单核重有显著相关性,鲜出核率与种长、种径、单种重、呈极显著负相关,与种长径比呈极显著正相关。     

两种大吴风草的耐荫特性研究

本文通过田间试验和叶绿素分析对上海地区两个品种大吴风草的耐荫性进行初步研究,结果表明大吴风草是喜半荫,耐荫的植物。大吴风草在遮光率达86.4%环境中生长良好,因此在完全郁闭度的树林或灌木丛下作地被具有良好的景观效果。     

Histological study of embryogenesis and organogenesis from anthers ofVitis rupestris du Lot cultured in vitro

Summary Anthers ofVitis rupestris du Lot were cultured in vitro at the uninucleate stage of the microspore, in order to investigate the histology of embryogenic and organogenic processes in this genotype. Microspores divided in the anther loculi resulting in the formation of globular structures with a ruptured exine. Somatic embryogenesis and, occasionally, caulogenesis and rhizogenesis occurred in calli produced from all anther tissues except the endothecium. The initial cell of the embryoid was surrounded by a jacket layer when situated deep within the callus. When the embryoid's initial cell was situated in the peripheral callus, a cutinized wall was present and the three-celled proembryoid was almost always segmented, showing the same embryonal type as the zygotic proembryo. Root differentiation and elongation and cap differentiation occurred during the growth phase in liquid medium. The mature root was diarch and contained cells with calcium-oxalate raphides, as seen in vivo. No starch or tannin deposition was ever observed in the mature embryoids.Abbreviations 6-BAP 6-benzylaminopurine - CC3 Nitsch and Nitsch (1969) basal medium - CS cross section - 2,4-D 2,4-dichlorophenoxy-acetic acid - LS longitudinal section     

Plant regeneration via somatic embryogenesis of Elymus sibiricus cv. ‘chuancao No. 2’

The mature seeds, mesocotyls, and young leaf tips of Elymus sibiricus L. cv. ‘chuancao No. 2’ were cultured on Murashige and Skoog (MS) medium supplemented with 5.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-d) and 0.05 mg/L kinetin in the dark at 26°C, the calluses were produced. The rate of callus regeneration depended on the explants source and plant growth regulators. Plants regenerated from whitish-yellow-coloured compact nodular callus formed after subculturing for 8 weeks. Higher frequency (54%) of shoot differentiation was obtained from the embryo tissues of mature seed than from either mesocotyls (24%) or young leaf tip tissues (6%) when these calluses from different types of explants were cultured on plant regeneration medium containing half strength MS salts supplemented with 0.1 mg/L kinetin, 1.5 mg/L 2,4-D and 20 g/L sucrose. The green plants were rooted within 6 weeks in the root regeneration medium, and over 97% of these soil-established plants were obtained in the greenhouse when potted in a sand and peat mixture medium.     

杉木优良变异类型——罗田垂枝杉生物学特性研究

罗田垂枝杉是20世纪70年代中期在湖北省罗田县发现的杉木自然变异类型,在与黄枝杉比较的基础上,对罗田垂枝杉的形态变异特征和生物学特性进行了深入的调查研究,其形态特征与其它杉木类型的主要区别是：2～3年生的侧枝自然下垂,6～7年生的老枝自然脱落,树冠窄小,是具有遗传改良品质和较高利用价值的种质资源。     

黄山贡菊的挥发油成分

The volatile oil in flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Gongju was extracted with steam distillation, the constituents and contents of volatile oil were analyzed by means of GC-MS-DS techniques. The result shows that the principle constituents of the volatile oil are bicyclo[3.1. 1]hept-2-en-4-ol, 2,6,6-trimethyl-, acetate (39.64%); benzene, 1-( 1,5-dimethyl-4-hexenyl)-4-methyl-,2-heptene (5.24%);n-hexadecanoic acid (4.77%); cis-lanceol (4.73%) ; acetic acid,1,7, 7-trimethyl-bicyclo [2.2.1] hept-2-yl-ester (3.95%); (-) spathulenol (3.38%) ; 2, 4, 6-trimethyl-3-cyclohexene-1-carboxaldehyde(3.22%) ; caryophyllene oxide (2.88%) ; 1,2,3,4, 5,6,7,8-octahydro-1,4-dimethyl-7-(1-methylethenyl)-,azulene (2. 80%); 3-(1, 5-dimethyl-4-hexenyl)-6-methylene, cyclohexaene (2. 50%); decahydro-1, 4a-dimethyl-7-( 1-methylidene)-,1-naphthalenol(2.39%);1,1,2-trimethyl-3,5-bis(1-methylethenyl)-,cyclohexane(2.23% ), etc.