题名雄全同株植物刺山柑(Capparis spinosa L.)花型数量变化及雄蕊分化对繁殖效率的影响
作者杨美琳
学位类别博士
答辩日期2015
授予单位中国科学院大学
授予地点北京
导师尹林克
关键词刺山柑 雄全同株植物 雄花和两性花比例 雄蕊形态与功能分化 繁殖效率
学位专业理学博士
中文摘要雄全同株植物刺山柑(Capparis spinosa L.)为山柑科(Capparaceae)山柑属(Capparis L.)多年生藤本半灌木,具有持续开花习性。据观察,同一植株上雄花和两性花的比例,以及居群中的雄花和两性花的比例,在整个生长季中均有不同;在雄花和两性花的同一朵花内存在着长、短不同的两类雄蕊,两类雄蕊在形态、数量和颜色上存在显著差异。为了探明刺山柑在持续开花过程中雄花和两性花比例变化规律及适应生物学机制,认知异长雄蕊功能分化的进化意义,以栽培条件下的成龄刺山柑单株和居群为研究对象,对其持续开花繁殖特性,雄花和两性花比例与有性繁殖效率的关系,刺山柑两种花型间同种雄蕊在形态、数量和颜色等方面的差异,花内长、短两类雄蕊的形态特征、花粉活力、花粉数量、直接参与繁殖过程中的功能作用以及与传粉者(昆虫)之间的关系进行了比较观察和研究。旨在解释该物种的生殖习性和生态适应机制,揭示其两种花型不同比例对结实是否有影响以及异长雄蕊的形态与功能选择压力下所表现出的进化意义,为该植物的繁殖生物学研究及阐明异长雄蕊的形态与功能选择压力下所表现出的进化意义提供新的理论依据。主要结论:(1)雄花和两性花分别存在2个开花高峰期,两者高峰期相互交错;雄花两次开花的开花数量和花期长度相同,而两性花两次开花的开花数量和花期长度不相同,两者存在极显著差异。(2)两个花峰期相比,雄花和两性花无论是长雄蕊还是短雄蕊,第一花峰期的花丝均比第二花峰期花丝长,但第一花峰期花药均显著短于第二花峰期。(3)两个花峰期之间,雄花和两性花的花粉数及花中长、短雄蕊花药的花粉数均无显著差异(P >0.05)。花粉活力在18-20h之间。开花后4-18h内柱头具有可授性;花粉活力和柱头可授性在两个花峰间无显著差异。(4)第一个花峰期坐果率高于第二个花峰期;第一个花峰期所结的果实大于第二个花峰期;第一个开花高峰期所结的果实包含的种子多且种子小;第二个开花高峰期所结果实包含的种子少且种子大。(5)雄花与两性花比例的变化与结实率的变化存在极显著相关,当雄花/两性花为5/5时,即雄性资源为雌性资源的三倍时,其结实率达到最高(82%);雄花和两性花比例的变化对果实质量和种子质量也有显著影响,当雄花/两性花为2/8时,即当两性花占80%时,所结果实最大最重,并且单个果实种子数最多;而当雄花/两性花为9/1时,即两性花占10%时,所结果实最小最轻,并且单个果实种子数最少,两性花增多提高了雌性适合度,种子数增多,则果实较大,反之亦然;当雄花/两性花分别为4/6、7/3和3/7时,结实率最低且种子最大,这说明当结实率低时,有限的种子可以从母株中得到更充足的资源。 (6)两种花型间同种雄蕊长度、颜色、单个花药花粉数、花粉可育率及昆虫访花情况均不存在差异。分别用两种花型长雄蕊和短雄蕊花粉进行单株的人工授粉试验,结果表明,授两种花型长雄蕊花粉,所得结实率及果实质量均无差异;但授两性花长雄蕊花粉所得单个果实种子数远远低于授雄花长雄蕊花粉所得单个果实种子数,且种子质量较好;授两性花短雄蕊花粉所得结实率高于授雄花短雄蕊花粉所得结实率,但所得果实质量、单个果实种子数及种子质量无差异。(7)雄花和两性花同朵花内的雄蕊在花丝长度上存在分化;长短两种雄蕊的雄蕊数量、花丝颜色和单花雄蕊花粉总数存在极显著差异;长雄蕊的雄蕊数量和雄蕊花粉总数显著大于短雄蕊;长、短两种雄蕊的花粉活力无差异。(8)昆虫访问长雄蕊的频率高于访问短雄蕊的频率。刺山柑的长雄蕊和短雄蕊在主导功能上均为“传粉型”雄蕊;而短雄蕊可有效提高不利天气环境(如大风和阴雨天气几乎没有昆虫访花)条件下自花授粉的雄性资源保障度,并在正常条件下给昆虫提供便利的花粉获取空间差和最大化的传粉几率,同时增加了昆虫单次访花时间。
英文摘要Capparis spinosa L. (Capparidaceae) is a woody perennial, with an extended flowering period. It is observed that the proportion of male flowers and perfect flowers are different in population even in the same plant. And the proportion is different in whole growing season. Each flower has both short and long stamen. In order to investigate proportional change rule and biological adaptability mechanisms under the extended flowering period, cognize evolutionary sense of heteranthery functional differentiation. The adult individual plant and population of C. spinosa were chosen as research objects. Reproductive characteristics of extended flowering, the relationship between male and perfect proportional and sexual reproduction efficiency, compare the morphology, number and the colour of same stamen between two kinds of flowers, the morphological characteristics, pollen vigor, the quantity of pollen, the function and the insect visiting between shorter and longer stamen were totally observed and compared. In order to explain reproductive habits and ecological adaptation mechanisms of C. spinosa, reveal if different proportion of male flowers and perfect flowers impact on fruit setting, the evolutionary sense of the morphological and function of heteranthery. It provide new theoretical basis for reproductive biology research and the evolutionary sense of the morphological and function of heteranthery of C. spinosa under selection pressure. The main results were as follows: (1) The flowering period was approximately five months long, during this period, two main and overlap flowering peaks emerged. Several significant differences between the two peaks were found: the number of flowers and duration of the flowering period for male flowers were identical in both peaks, but differed for perfect flowers (contain stamens and pistil) ; (2) The filaments of both long and short stamens in male and perfect flowers in the first peak were longer than those in the second, whereas anther length showed the opposite trend; (3) Pollen vitality of C. spinosa was highest (>80%) 2-6 h after anther dehiscence, as pollen grains remained viable for 20h. No difference in the pollen vitality of both male and perfect flowers was observed. The stigma receptivity of perfect flowers was highest 4-8 h after the flower opened. It lost receptivity 16-18 h after opening and the petals had wilted. No difference in stigma receptivity between the two peak flowering periods was apparent. (4) The frequency of fruit set and size in the first peak was respectively higher and larger than the second; and the seeds produced in the first peak were smaller and lighter than the second. (5) The proportions of male and perfect flowers were manipulated manually and the impact on fruit set and quality, and on seed number and quality, was assessed. Fruit set differed significantly among the different flower proportions. Under a male flower: perfect flower ratio of 5:5, the male resources: female resources ratio was 2:1 and fruit set was the highest recorded (82%). The relative proportions of male and perfect flowers significantly affected fruit and seed quality. Fruit were largest and heaviest, and number of seeds was highest, under a male flower: perfect flower ratio of 2:8, whereas the fruit were smallest and number of seeds was fewest under a male flower: perfect flower ratio of 9:1. Under male flower: perfect flower ratios of 4:6, 3:7, and 7:3, fruit set was lowest but the seeds were largest and heaviest, which indicated that fewer seeds could receive higher resource allocation by the plant. This study reveals why C. spinosa products perfect flowers not female flowers. (6) The length, colour, number of pollens of single anther, fertile pollen rate and the insect visiting of the same stamen had no significant differences between male flowers and perfect flowers. Through the artificial pollination experiment, the perfect flowers with no stamens were pollinated the pollen of the longer stamens in two kinds of flowers, the fruit rate and the quality of fruits had no differences between two kind of flowers. However, the number of seeds from the pollen of longer stamens of perfect flowers were lower than the number of seeds from the pollen of longer stamens of male flowers. The fruit rate from the pollen of shorter stamens of perfect flowers were higher than that from the pollen of shorter stamens of male flowers, but the quality of the fruits and the seeds, the number of seeds in single fruit had no significant differences between two kind of flowers. This study provides the rationale and the basis to compare the morphology and the function between longer stamen and shorter stamen in the same flower. (7) Male and perfect flowers all had longer and shorter stamens in a single; the number of the stamen, the colour of the filaments and the number of pollen in a single flower had significant differences between longer and shorter stamen. The number of longer stamen of pollen in a single flower was more than those of shorter stamen. Pollen vigor had no difference between longer and shorter stamen. The insects visited frequency of longer stamen was higher than that of shorter stamen. The pollen of longer stamen and shorter stamen were respectively used for hand pollination, it was proved that the fruit and seed rate from the pollen of longer stamen were higher than that of shorter stamen. (8) In short, long- and short-level stamens of C. spinosa could be described as "pollinating" stamens. Their main function were povide pollen and visiting by insects were the main function of longer stamens, and the shorter stamens could improve the male resources guarantee in the bad weathers, provide a more convenient space for pollen captured and to the maximize pollination probability, increased the single insect visiting time. This research provides an evidence to reveal the morphology and function of dimorphic stamens in C. spinosa. It has shown the evolutionary sense under the selection pressure.
语种中文
学科主题植物学
内容类型学位论文
源URL[http://ir.xjlas.org/handle/365004/14932]  
专题新疆生态与地理研究所_研究系统_荒漠环境研究室
作者单位中科院新疆生态与地理研究所
推荐引用方式
GB/T 7714
杨美琳. 雄全同株植物刺山柑(Capparis spinosa L.)花型数量变化及雄蕊分化对繁殖效率的影响[D]. 北京. 中国科学院大学. 2015.
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