【作者】 何爽；

【导师】 谭敦炎；

【作者基本信息】 新疆农业大学 ， 植物学， 2004， 硕士

【摘要】 本文从形态和物候特征、胚胎学和幼苗特性等方面对新疆阿魏的生物学特性进行了研究，在此基础上对新疆阿魏、托里阿魏、多伞阿魏和全裂叶阿魏的繁育特性进行了比较，主要结果如下： 1．新疆阿魏为多年生一次结实植物，其生活周期可分为营养生长期和生殖生长期两个阶段，且前者远长于后者。在种子萌发后的第一个生长季中，其幼苗生长期约为62d，此后每年的营养生长期均不足90d；进入生殖生长季后，其植株的生长期约为77d。因此，该种为长生活周期短生长期的类短命植物。 2．新疆阿魏小孢子母细胞的减数分裂为同时型，小孢子四分体为四面体型和十字交叉型，成熟花粉粒为3—细胞型，散粉前，营养核解体。雌蕊二心皮合生成二室，中轴胎座，每室一枚胚珠，倒生，且在其上方的胎座上有一退化胚珠，并于正常胚珠双受精后解体。单珠被，薄珠心，胚囊发育为蓼型。有珠被绒毡层和珠孔塞。成熟反足细胞具双核。胚乳发育为核型。胚乳细胞壁较厚，细胞中含有大量PAS染色呈正反应的物质，有巨形细胞发生。胚胎发生为茄型，四细胞原胚为直线形，八分体原胚的顶部由两排各4个细胞组成。成熟种子内，胚已分化出胚根、胚轴、胚芽和子叶。 3．四种阿魏都是性单型、雄全同株繁育系统。两性花自下而上先于雄花开放，1～2 d后雄花也以自下而上的顺序相继开放；两性花开放时，花柱先于花药伸出花被。新疆阿魏和托里阿魏的雄花／两性花比值均为5∶1，多伞阿魏为4∶1，而全裂叶阿魏为1∶5。多伞阿魏的P／O值为2300∶1，属兼性异体异花受精，而其它3种阿魏的P／O值均比多伞阿魏高，属异体异花受精。新疆阿魏的雌性影响因素仅为3.7％，对结实产生了极大影响。花粉量不是影响新疆阿魏结实的主要因素。 4．从繁育特性的角度看，新疆阿魏植株上较低的两性花比例、较低的雌性影响因素、较高的果实虫食率及自种子散布至萌发期间较高的种子死亡率，都是引起新疆阿魏濒危的因素。但过度放牧和无计划的大肆采挖等人为因素才是导致其濒危的根本原因。 5.首次发现了新疆阿魏的雄性不育现象。从细胞学角度看，其雄性不育主要表现在药壁和次级造抱细胞的异常发育两个方面。而且绒毡层的缺失直接导致了雄性生殖细胞营养缺乏或营养不良，从而最终导致其败育。 6.新疆阿魏幼苗期有5个快速生长的阶段:(l)种子萌发后，胚根和下胚轴迅速伸长;(2)子叶出土后迅速长长、增宽;(3)子叶展开后，主根迅速伸长; (4)第一片真叶展开后，主根迅速进行加粗生长;(5)第三片真叶展开后，主根同时进行快速的伸长生长和加粗生长。在第一个生长季，新疆阿魏的子叶始终为有功能的同化叶。更多还原

【Abstract】 The biological characteristics of Ferula sinkiangensis K. M. Shen including its morphological and phenological characters, embryology, reproductive characteristics and the growth characters of seedlings have been studied in this paper. Based on which, the breeding systems of F. sinkiangensis, F. krylovii, F. ferulaeoides and F. dissecta are compared. The main results are as follows:1. F. sinkiangensis is a kind of perennial, monocarpic plant. Its life cycle can be divided into two stages: vegetative growth period and reproductive growth period. The former is much longer than the later. The period of seedlings growth in the first growth season is about 62 days. The vegetative growth period every year is less than 90 days before this species enter into reproductive growth. The reproductive growth period of this species is about 77 days. Therefore, F. sinkiangensis is an ephemeral plant with long life cycle and short period of growth every year.2. The microspore mother cells undergo meiotic divisions. Cytokinesis is simultaneous, and tetrads are tetrahedral or decussate. The mature pollen grains are three-celled type. But the vegetative nuclei disintegrate before the shedding of pollen grains. The ovary is bicarpellary and integrated into double locule, axial placenta. Each locule contains a single ovule. The ovule is anatropous, unitegmic and tenuinucellar. Generally, there is an abortive ovule as well as the normal ovule in each locule, and it disintegrates after the double fertilization occurs in the normal embryo sac. The chalazal megaspore of a linear tetrad develops into a Polygonum type of embryo sac and there are double nuclei in each mature antipodal cell. The endosperm is of the Nuclear type. The cell walls in mature endosperm are much thicker and there are many substances in those cells that can be stained by PAS. Also, some large cellscan be observed. The embryogeny conforms to the Solanad type. The four-celled proembryo is linear.3. All the four species are sexually monomorphic and functionally andromonoecious. The lower hermaphrodite flowers usually bloom earlier than the upper, and one or two days after the lower hermaphrodite flowers bloom, the lower male flowers begin to bloom. In the hermaphrodite flowers, stigmas spread out of corolla earlier than anthers. The floral ratio of male to hermaphrodite in F. sinkiangensis and F. krylovii are both 5 to 1, and in F. ferulaeoides and F. dissecta it is 4 to 1 and 1 to 5 respectively. The pollen/ovule value in F. ferulaeoides is 2300 to 1, which conforms to geitonogamy and in other three species the value are much higher, which conforms to xenogamy. The female impact factor in F. sinkiangensis is only 3.7% and it influences the fruit set greatly. The pollen limitation is not the major factor that decreases its fruit-set.4. In the case of reproductive characteristics the low proportion of hermaphrodite flowers, the low female impact factor, the high insect-eaten rate of fruits and the high seed death rate from seed dispersion to germination are all factors that endangered F. sinkiangensis. But the artificial factors including over-grazing and unplanned digging are the real reasons that make its extinction.5. The male sterile in F. sinkiangensis is first reported. It displays abnormal developments in both anther walls and secondary sporogenous cells. And the lack of tapetum make nutrition insufficient to male reproductive cells, which leads to its sterile finally.6. There are five rapid growth stages of seedling. First, after the seed germinates, the hypocotyl and the radicle elongate rapidly. Second, the epigeous cotyledons elongate and widen quickly. Third, the main root elongates fast when the cotyledons spread. Forth, diameter of the main root quickly increases when the first leaf spreads. The last, length and width of the main root raise simultaneously when the third leaf spreads.更多还原