Observation of fiber ultrastructure of Ligon lintless mutant in upland cotton during fiber elongation

Lintless mutant is a super-short fiber mutanl in upland cotton only 4-8 mm in fiber length and also named Ligon cotton controlled by one dominant gene Li1. Fiber ultrastructure of the mutant (Li1) and its its wild (li1) in siti and in vitro was observed under an electron microscope to understand its cytological characteristics during the fiber cell elongation. The resulls showed that the mutant fiber in situ had thinner cytoplasm, more small vacuoles, less mitochondria, Golgi apparatus and endoplasmic reticula, and there were more starch granules which were free or packed in the amyloplast beside the cell wall than thai of wild type. It was indicated that scarcity of functional organelles and disability of transformation from starch to sugar might be associated with the tact that the mutant fiber cell was aborted too early to elongate into normal length. Mutant ovule in some media containing GA3 could produce a kind of huge callus that grew faster than normal ovules. The callus was covered with many white, loose, and semitransparent fiber-like cells that apt lo get off from ovule. These fiber-like cells were multicellular fibers generated by cell division and had black dots just like pigment glands in the stem and leaf of cotton. There were lots of micro-tubes beside cytoplasm membrane uf the multiecllular fiber, which were thought to be primary preparation for second wall deposition of multicellular fiber. It was indicated that GA3 might induce the expression of gene(s) that kept inactive in the field condition and then stimulate the original fiber cell in vitro to undergo divisionagain.     

一个新的水稻矮秆突变体sd-sl的遗传与基因定位研究

新的矮秆基因的发掘、研究和利用对水稻育种和植物生长发育机制研究有重要的作用.用60Coγ射线辐照粳稻9522,获得一个能稳定遗传的突变体.该突变体表型为株高较野生型矮,叶片短而微卷.将该突变体与籼稻广陆矮杂交,F2代呈3∶1分离,说明该突变体受隐性单基因控制.通过InDel分子标记对F2代分离群体进行遗传定位,将该基因定位于第6染色体InDel标记OS604附近.随后又发展了多对有多态性的InDel分子标记,将该基因座位精细定位在InDel标记XL6-6和XL6-1之间,AP003490和AP005619上,两个引物之间的物理距离为118 kb.本研究为该克隆基因及其作用机理的探究奠定了基础.     

含有嗜杀质粒的核融合缺陷突变株原生质体制备及再生条件的研究

利用由藤黄节杆菌(Arthrobacter latevs)分泌的,以β—1.3葡聚糖酶为主的酵母细胞壁溶解酶(Zymolyase),对含有嗜杀质粒的核融合缺陷突变株5045(α,his4,karl—1[KIL—K_1]rho~+)进行破壁,得到该菌株破壁,再生的最佳条件。为嗜杀酵母原生质体融合育种提供了依据。     

Effect of hyperthermia upon gamma-ray induced crossing-over in an excision repair deficient maleDrosophila melanogaster

Summary Hyperthermia of 1 h at 38°C did increase gamma-ray induced crossing-over in meiotic cells of male larvae and adults. However, there was considerably less effect of the heat treatment upon radiation induced crossing-over (a chromosome breakage event) in an excision repair mutanty mei-9 ^a.5 January 1987     

ph突变体和电离辐射在太谷核不育小麦研究中的利用

太谷核不育小麦自1972年被发现以来,人们在对它的理论研究和实际应用等各方面都开展了大量的研究工作。本文通过核不育小麦与“中国春”ph突变体杂交的方法,选育带ph突变基因的太谷核不育小麦,并以蓝粒小麦为供体,利用电离辐射方法对核不育小麦籽粒附加标记性状进行了初步探索,统计了携带Tal基因的4D染色体和控制篮胚乳性状的4E染色体在双单体情况下通过雌配子的传递频率。同时对蓝粒小麦、太谷核不育小麦、“中国春”ph突变体及杂交各代进行了细胞学观察,并在此基础上对太谷核不育小麦雄性不育性的原因以及在诱发染色体易位进行基因转移的过程中,利用ph突变体和电离辐射两种方法的特点及应用进行了研究和讨论。     

关于高校体育教育与学生终身体育锻炼的探讨

根据中国高校体育教学大纲特点和终身体育锻炼的需要,提出高校体育教育要以终身体育和"健康第一"的思想为主,对高校体育教育中培养学生终身体育锻炼习惯和能力的有关问题进行探讨.     

三种酸浆属植物的染色体核型分析

本文报导了采用根尖分生组织常规压片法,按Leva(?)等人的染色体分类方法和Stebbins的核型不对称性分类标准对挂金灯(Physalis alkekengiVar.francheti)、通肯酸浆(ph.ixocarpa)及毛酸浆(ph.pubescens)等三种酸浆属(physalis)植物进行染色体核型分析的结果,为探讨该属植物的进化、分类及品种选育提供了基础资料。     

双元载体提供组蛋白H3/H4拷贝1的elp3Δ菌株的构建

人Elongator是在转录中有功能的组蛋白乙酰转移酶(HAT)复合物,为研究其催化亚基Elp3功能,构建了酵母组蛋白H3/H4拷贝1的双元表达载体pRS316CFT,通过PCR介导的基因敲除,获酵母基因组H3/H4缺失由双元载体提供单拷贝H3/H4的elp3Δ菌株.敏感性实验表明该载体提供H3/H4可维持酵母正常生长.本工作为构建H3/H4乙酰化位点突变菌株,用功能互补在体内研究人Elp3 HAT活性功能奠定了基础.     

响应面法提高红曲黄色素的色调

在单因子的研究基础上,用响应面方法优化红曲霉突变株(Monascus anka mutant MYM2)的发酵培养基,来提高红曲色素中的黄色素色调。研究发现,葡萄糖、硝酸铵和磷酸二氢钾对红曲黄色素色调影响很大,它们对色调的影响有最低浓度值,分别为1.42%,0.67% 和0.57%,其理论色调值为4.58。根据模型方程,重复五次实验,其色调的平均值为4.21,黄色素色价达到88.14(U/mL)。     

鼠伤寒沙门氏菌JL65色氨酸合酶trpB基因的克隆、测序和相关特性的研究

用ＰＣＲ方法从鼠伤寒沙门氏菌（Ｓａｌｍｏｎｅｌｌａ ｔｙｐｈｉｍｕｒｉｕｍ）ＪＬ６５染色体ＤＮＡ中扩 增了ｔｒｐＢ基因片段,克隆到ｐＢｌｕｅｓｃｒｉｐｔ　Ⅱ ＳＫ（＋）质粒上,并用双脱氧未端终止法测定了其 核苷酸序列．ＪＬ６５ｔｒｐＢ基因和ＷＴ Ｓ．ｔｙｐｈｉｍｕｒｉｕｍ　ｔｒｐＢ基因作比较后,发现仅有３处的核苷 酸差异,其中ｔｒｐＢ基因在的１００位由Ｃ突变为Ａ,１１１位由Ｇ突变为Ａ,１０３０位由Ｇ突变为 Ａ,导致３４位氨基酸残基Ａｒｇ变为Ｓｅｒ,３４４位的Ｇｌｙ变为Ａｒｇ,氨基酸性质均发生变化．说明 是 ｔｒｐＢ１００,ｔｒｐＢ１０３０两处核苷酸的突变使ＪＬ６５的β亚基发生改变,并可能导致ＪＬ６５的冷 敏感．根据互补试验及酶活测定结果,初步将ＪＬ６５ｔｒｐＢ归类于“可修复”的错义突变型．