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61.
十字花科植物花蜜腺的比较形态学研究   总被引:24,自引:0,他引:24  
十字花科植物普遍具有花蜜腺。通过对该科9族、36属的74种和1变种植物花蜜腺的形态和结构的比较研究,发现它们的内部结构都由分泌表皮、产蜜组织以及维管束(有些种类缺乏)组成。分泌表皮上分布有变态气孔器,为分泌蜜汁的通道。其外部形态多样,花蜜腺的数量、形状、组成和着生位置等在同族的不同属或同属的不同种间都存在一定差异。根据花蜜腺在分布、形态和结构上的差异可将该科植物花蜜腺分为侧蜜腺型,侧中蜜腺型和环状蜜腺型,在三型下又可划分出19个亚型,并对该科各类型花蜜腺的形态演化关系以及各族间的亲缘关系进行了探讨。  相似文献   
62.
十字花科蔬菜上黄瓜花叶病毒分离物的比较研究   总被引:16,自引:0,他引:16       下载免费PDF全文
对从杭州市郊青菜、萝卜、花椰菜上分离的6个CMV分离物进行了生物学、血清学及双链RNA比较研究。生物学测定结果表明,不同分离物在所测定的6种十字花科蔬菜上的致病力有差异。6种分离物颗粒形态、衣壳蛋白分子量和血清学方面无差异,且都属血清型Ⅰ。dsRNA分析结果表明,6个分离物的dsRNAl,2,3和4在PAGE中迁移率相似,但在1.5kb~0.4kb之间有多条量相对较少的条带,这些条带在不同分离物之间差异较大。6个分离物均含有卫星RNA。  相似文献   
63.
64.
独行菜属植物叶片脉序的比较观察   总被引:7,自引:0,他引:7  
对独行菜属(Lepidium)8种,1变种进行了叶片脉的比较观察,结果表明:它们的一级脉中等粗细,基部1~2对侧生,一级脉与二级脉连志成拟环结两行羽状脉;三级脉贯穿型或结网型,叶缘末级脉为不完全型,网眼大小,形状不规则,发育均为不完善型,可为探讨十字花科的系统演化提供一些形态学依据。  相似文献   
65.
The metabolism of zeatin, N6-(Δ2-isopentenyl) adenine, dihydrozeatin, zeatin-O-glucoside and dihydrozeatin-O-glucoside has been studied using derooted radish seedlings. The metabolites were identified by UV and GC/MS. The patterns of metabolism are compared and provide evidence that the O-glucosyl conjugates may be storage forms of the cytokinins.  相似文献   
66.
Benzylglucosinolate degradation products were analysed in extracts of the seedlings of Lepidium sativum (‘curled cress’ and ‘plain cress’). Benzyl thiocyanate was positively identified in extracts of both types of cress, but it could not be detected after the onset of development of the true leaves. The relative percentages of benzylglucosinolate degradation products varied appreciably with age of the seedlings and with the length of time the shredded plant material was allowed to autolyse. Both types of cress behaved similarly on autolysis but differences were observed with seedling age.  相似文献   
67.
Lipids from cultured cells, leaves and seeds of two varieties each of soybean (Glycine max) and oil seed rape (Brassica napus) were separated into neutral lipids, glycolipids and phospholipids and their fatty acids were analysed. Usually, the fatty acid composition differed between corresponding fractions from cultured cells, leaves and seeds. Differences were least marked in (i) the phospholipids from cultured cells and leaves of soybean and (ii) the neutral lipids from cultured cells and seeds of rape. In the cultured cells, the fatty acid composition of the phospholipids differed from that of the glycolipids and neutral lipids, and fatty acids of chain length greater than C18 comprised a large proportion of the fatty acids of the glycolipids.  相似文献   
68.
Nine acylated glycosides of kaempferol or quercetin were identified in Sisymbrium gilliesii, and in three Crambe spp. They were usually present together with the related unacylated glycosides. Acylation is a very common characteristic of the four crucifer species studied.  相似文献   
69.
Autolysis products of nine species of the Cruciferae and two species of the Capparaceae were analysed by high sensitivity GC/MS. Four of the Cruciferae species were examined for glucosinolates for the first time. One new glucosinolate, 9-methylthiononylglucosinolate, was identified in Arabis purpurea and many known glucosinolates were identified for the first time in previously studied plant species. 5-Methylthiopentylglucosinolate appears to be characteristic of the genus Alyssum.  相似文献   
70.
Seeds of natural populations of Capsella bursa-pastoris, collected from temperate regions, weighed less and had a higher lipid content than those from colder regions. The long-chain (16:0, 18:0, 18:1, 18:2 and 18:3) and very long-chain (20:0, 20:1, 20:2 and 20:3) fatty acid compositions were, however, quite similar in the lipids of all the seed samples which indicates a rigid genetic, rather than environmental, control of fatty acid biosynthesis. Characteristics of the seeds of the diploid species C. rubella and C. grandiflora were similar to those of the tetraploid C. bursa-pastoris, with the exception of the distinctly lower lipid content in C. grandiflora seeds.  相似文献   
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