【摘要】 本文报道关于菸草和辣椒花药离体培养的研究结果。对于菸草花药离体培养曾进行四种培养基的对比试验,结果以 NH 效果最好,Blaydes 次之。10—20%(体积/体积)椰乳能提高花药成胚的百分比,对单倍体幼苗也有促进作用。蔗糖浓度从1—4%都能产生“胚状体”,以3%的蔗糖浓度产生“胚状体”的百分比最高,长出的幼苗也比较健壮。对花粉不同发育时期进行了比较试验,花药中花粉单核靠边时期进行培养的出苗率最高。“胚状体”的形成主要由单核花粉粒均等分裂或由营养核分裂两种方式形成“胚状体”。生殖核只进行几次分裂而最后逐渐退化消失。对菸草花粉植株进行根尖或茎尖制片,观察其染色体数目为24,证明是单倍体。用不同浓度的秋水仙碱对单倍体植株进行染色体加倍,得到许多二倍体后代,其中少数是四倍体。本文对花药离体培养和组织培养中产生“胚状体”问题进行了讨论。辣椒采用花粉单核靠边时期的花药,培养在 NT 及 MS 加有补充物质的培养基上,花药既产生“胚状体”又产生愈伤组织。观察到单核花粉最初分裂发育成多细胞“原胚”到最后形成幼苗的过程。“胚状体”的发育与合子胚的发育过程相似。在花粉发育成幼苗的各个发育时期都可能停止发育,长成幼苗的只是少数。由单核花粉粒所形成的多细胞“原胚”可突出花粉壁外但仍与花粉粒相连,花粉粒内细胞大而染色淡,花粉壁外的多细胞“原胚”的细胞排列紧密,体积小而有分生能力,有的已开始分化。小苗的根尖和愈伤组织细胞,用醋酸洋红压片检查,其染色体数目为12,证明是单倍体。更多还原

【Abstract】 The present article deals with an investigation on the anther culture in vitro of tobacco and red pepper. The tobacco anthers were cultured in vitro on 4 different media.Best result was obtained with Nitsch H medium;Blaydes was ledd effective.The percentage of the embryoids formation increases with the addition of 10—20%(v/v)cocoanut milk.The embryoids may be induced with sucrose from 1—4%;and 3% is the optimum. The anthers of different developmental stages were cultured in vitro for com- parison.It is found that when the anther with its pollen grains at the 1-nucleate stage,while the nucleus is situated on one side of the pollen,is the best material for haploid seedling induction. The embryoids were mainly formed in two ways:They were formed either from the development of equal division of the 1-nucleate pollen grain or from the vegetative nucleus of the unequal division of the 1-nucleate pollen grain.The generative nucleus may divide only once or several times but eventually the nucleus and its derivatives degenerate. The chromosome number of the root tip or shoot apex of the pollen plants is found to be n=24;the haploid nature of this plant was confirmed.Colchicine of different concentrations was used to double up the chromosomes of the haploid plantlets.In this way many diploids were obtained and among them a few were tetraploids.The production of the embryoids by different means was discussed. The red pepper anthers were cultured in vitro on NT and MS media,supplemented with different growth substances at the stage when its only nucleus is situated on one side of the pollen grain.The anthers gave rise to embryoids and calli.The develop- ment of the 1-nucleate pollen grain through“proembryo”to the formation of the seed- ling was observed.The development of the embryoids is similar to that of the zygotic embryo. The development of the embryoids from the pollen grains may cease to grow at any stage,hence a few of them may develop into seedlings. The connection between the multicellular“proembryo”and the pollen grain can be seen.The cells inside the pollen grain are large and stained lightly,while the cells of the embryoids outside the pollen grain are small,meristematic and closely arranged; some of them being in the initial stage of differentiation. The cells of the root tip and the callus have been examined with aceto-carmine squash method.The chromosome number was found to be n=12;therefore these plants and calli are haploids.更多还原