金琥的离体快速繁殖

1 植物名称 金琥(Echinocactus grusonii ) 。 2 材料类别 幼嫩的小球。 3 培养条件 (1)诱导小球培养基为B5+BA 2.0 mg·L-1(单位下同)+NAA 0.2;(2)增殖培养基为B5+BA 0.8+NAA 0.08;(3)生根培养基为1／2B5+BA 0.3+NAA 0.05。3种培养基中蔗糖均为3％,琼脂为0.7％,pH5.8左右,培养温度为(25±2)℃,光照度为2 000 lx,每天光照10 h。 4 生长与分化情况 将金琥小球下部切去1／2,留下上半部,用清水清冼干净,再用无菌水洗5～6次后切成小块,接种到培养基(1)上,经过45 d,刺座开始隆起,1周后,在隆起处开始分化小球,并慢慢长大。 金琥的增殖培养基中,BA浓度超过2.0ng·L-1易导致玻璃化,低于0.5 mg·L-1则增殖缓慢。如利用培养基(1)进行继代增殖,玻璃化十分严重。     

TGF-β1短时处理降低肝癌细胞与Fn的粘附及FAK的磷酸化

为了研究TGF-β1对α5β1整合蛋白所介导的信号转导通路是否有快速的信号调节作用,本文用TGF-β1短时(10min)处理SMMC7721细胞,发现当经TGFβ1预处理的细胞与Fn粘附时,细胞与Fn的粘附力下降,由Fn与整合蛋白的结合而诱导发生的FAK的酪氨酸磷酸化随着TGF-β1浓度的增加而降低。而TGF-β1短时处理并未改变整合蛋白α5、β1亚基的表达。此外,贴壁生长于培养皿的细胞的FAK磷酸化程度在TGF-β1短时处理后也下降,甚至检测不出。提示TGF-β1可能通过某种信号通路快速调节了整合蛋白与配体的亲和力以及下游信号分子FAK的磷酸化。从而影响了细胞内骨架蛋白结构的完整性,使细胞发生去极性化,有利于细胞在迁移早期的松脱。     

不定胚再生植株的染色体数目变异

本实验以甜瓜“小麦瓜”和“青皮绿肉”品种为试材,经不定胚诱导再生植株。分别调查了不同继代培养时间后形成再生植株的染色体数目,并将之与对照染色体数目相比较,发现通过诱导不定胚所得到的再生植株中存在着一定的变异,而且经过不同继代培养时间后,所得到的不定胚再生植株的变异程度不同,随着时间的增加,染色体数目的变异率从3.3%增加到30%,变异幅度也从2n=23~24增加到2n=13~48。从而得出结论：不定胚再生植株染色体数目变异程度随着培养时间的增加而增加;培养时间在1~2个月内所得到的不定胚再生植株的变异较少。此外,不定胚再生植株的染色体数目变异程度也因品种而异。 Abstract:Chromosomal number of different of somatic embryos regenerated plants were investigated in melon variety “xiaomaigua” and “Qingpilurou”.Certain variations of chromosomal number were found among the regenerated plants compared with normal sample,and range of variation covered from 2n=23～24 to 2n=13～48 with the increase of generation,the rate from 3.3% to 30%.The results indicated that degree of variation in chromosomal number of somatic embryos regenerated melon plants increased with the time of culture,and those cultured in one to two months had the least variation.It was also found that degree of chromosomal number variations varied with melon varieties.     

Embryogenesis of Polyembryonic Rice ApⅢ: Structural and Histochemical Studies of Egg Apparatus Around Fertilization

The structural and histochemical changes of the egg apparatus in the polyembryonic rice (Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before and after fertilization were studied and compared with those of normal and other polyembryonic rices in a similar developmental period. A total of 2 932 ovules were observed and each of them contained only asingle embryo sac with a set of egg apparatus. Among 1 655 embryo sacs, there were 1 643 embryo sacs (99.27%) with one normal egg apparatus in each embryo sac, and only 12 embryo sacs (0.73%) from the remainder with 4 celled egg apparatus, i.e. two eggs and two synergids. Neither the numerous poly egg apparatus and egg like cells, nor the double set of embryo sacs each containing one egg apparatus and other abnormal egg apparatus in single ovary, which were reported by earlier investigators to have high frequency of embryo production in SB 1 and ApⅣ, were observed. The egg cell was located at the subterminal site of the micropylar end of embryo sac. The cytoplasm of egg cell was rich in protein materials and poly saccharide grains, which did not disappear until the division of zygote. The prominent nucleus was closely surrounded by protein and polysaccharide grains, which did not disappear until the division of zygote. No cytological difference was found between egg cells from the normal and abnormal egg apparatus. The two synergids were fully developed and situated at the upper most part of the micropylar end of the mature embryo sac. In most embryo sacs, the synergids were flask shaped with longer necks, and a widened cap shaped top, in close contact with the micropyle. The synergids had a well developed filiform apparatus. The characteristic appearance of the filiform apparatus as well as the cap neck region of synergids before and after pollen tube penetration were easily distinguishable from the egg cell. The structure, the stainability with Coomassie Brilliant Blue and PAS reaction, the process of accumulation, distribution and disapperance of the cytoplasmic protein materials and polysaccharide grains of the two synergids, the persistent and rarely the receptive synergids before and after pollen tube penetration, were closely similar to those of egg cell of the same developmental stage. In comparison with normal and other polyembryonic rice reported, the size of nucleus and nucleolus and their stainability also strongly resembled those of egg cell. Based on the results observed, the main conclusions are summarized as follows: (1) the additional embryos very frequently developed in the young and mature seed of polyembryonic rice ApⅢ were produced by one or two synergids of normal egg apparatus, rarely by 4 celled egg apparatus; (2) during fertilization, the synergids, in addition to the natural specific function of introducing pollen tube and transferring sperms to egg cell and central cell, could be closely associated with the potentiality to breed one or two additional embryos; and (3) as compared with that of normal or other polyembryonic rice it is firstly disclosed that in a few embryo sacs of ApⅢ, the cytoplasmic and nuclear structure, the active anabolism and catabolism of protein and polysaccharide materials and the delayed disorganization at the mid basal region of the receptive and persistent synergid still remained unchanged before the division of zygote. Such salient features could be the predisposition for the origin of additional embryos in ApⅢ.     

鹅观草属的系统发育分析

根据分支系统学的原理和方法, 对禾本科鹅观草属进行了系统发育分析。鹅观草属传统分类上的18 个系被确定为终端类群, 来自形态学、解剖学、细胞学和孢粉学的23 个性状被选作建立矩阵的依据;雀麦族中的短柄草属作为外类群被用于外部性状的极性识别, 过去分析过的性状资料被用于微观特征的极性判断;采用PAUP 程序对矩阵进行运算, 共获得6 个同等简约的谱系分支图, 其中具最低f-比值的图被选作分支分析的基础。结果表明, 分支图上显示的组、系划分与传统分类的基本一致, 各类群间的演化关系与过去凭借单一证据所作的零散推断也基本吻合。所不同的是半颖组各支类群不是共祖起源, 可能具有复杂的内部组成;在个别系间, 分支图展现的类群位置与宏观分析的存在差异。     

云南白族人群Y染色体DYF155S1基因座多态性研究

揭示云南白族136例无关男性个体Y染色体小卫星DYF155S1基因座多态性。用已建立的AmpFLP和MVRPCR方法分析DYF155S1基因座长度多态性、5′端多态性、3′端多态性。DYF155S1基因座具有高度多态性,基因多样性（h）达09996。研究表明将AmpFLP和荧光MVRPCR结合起来更能充分揭示DYF155S1基因座多态性,可为遗传学、人类学及法医学的研究提供有效的工具和基础资料。     

施肥对小粒咖啡生长、光合特性和产量的影响

采用田间实验,研究了不同N、P、K匹配对3年生小粒咖啡生长、光合特性以及产量的影响．结果表明,N的缺乏对小粒咖啡生长、光合特性和产量的影响最大,其次为K,而P的影响相对较小．叶面喷施适量的微量元素(B、Zn)可明显增加产量．N、P、K不同水平的匹配对小粒咖啡有不同的影响,N：P2O5：K2O的最佳匹配比例为1：0．5：1．小粒咖啡需要高营养的投入,而从投入．产出的效益分析表明,N、P,O5、K2O的合适用量分别为100、50和100g／株．小粒咖啡产量与单株分枝数和单株叶面积密切相关,与最大净光合速率呈显著正相关,但与苗高、地茎的相关性不显著．不同施肥处理对小粒咖啡黎明光化学效率影响不大,但高的施肥量明显减轻咖啡的日间光抑制．     

辽西人工林气候生产力分析

采用6种方法计算了辽西地区的人工林气候生产力。结果表明,辽西平均人工林生产潜力为8．8t·hm^-2．年^-1,其分布趋势从东南向西北逐渐降低,与降雨量分布一致。针对地区特点,生态地区法、层次递推法和综合模型是适宜的气候生产力计算模型。对比分析表明。辽西现实人工林生产力水平处于极低水平。提高人工林质量,挖掘生产潜力是今后人工林发展的关键．     

Magainin和cecA-mil抗菌肽基因的密码子优化及在毕赤酵母中的高效表达

选用毕赤酵母偏爱密码子 ,设计合成了新型抗菌肽基因。所合成的magainin基因和cecA mil杂合肽基因全长分别为 1 0 1bp和 60bp ,并在其N端引入kex2裂解位点 ,以保证表达抗菌肽具有天然N端。其中 ,cecA mil杂合肽基因根据cecropinAN端第 1～ 7个氨基酸残基、melittinN端第 5～ 1 2个氨基酸残基所设计合成。基因分别克隆入pPICZα A质粒 ,构建分泌型重组酵母表达载体pPICZα A mag和pPICZα A CM。在AOX1 (醇氧化酶 )启动子调控下 ,类似天然抗菌肽大小的magainin及cecA mil蛋白获得分泌表达 ,其表达量分别为 1 0 5mg L和 1 1 8mg L。初步抑菌活性测定 ,显示两者对金黄色葡萄球菌及E .coliDH5α有较好的抑杀活性。