枸杞胚乳植株的研究及应用潜力

本文对10株不同倍性的(2x,3x,4x,混倍体)构杞胚乳植株进行了研究。观察到3x,4x和混倍体植株的气孔、叶片、花药较二倍体枸杞增大。花器有明显的变异现象。育性显著降低,种子中多数是秕粒。3x植株中有二株,平均每个果内仅有2.7和3.3粒饱满种子,比对照分别减少91.8％和89.9％。在3x植株的减数分裂过程中,观察到许多染色体行为异常现象。     

STUDY OF ENDOSPERM PLANTS OF Lycium barbarum L. AND ITS POTENTIALITY FOR PRACTICAL USE

This paper reports morphological differences between diploid, triploid, tetraploid, mixploid endosperm plants and the original diploid plants. In comparison with original diploids, the triploid, tetraploid and mixploid endosperm plants have larger stomas, greater variability in flowor organs, decreased fertility, decreased seed set per fruit, and a lot of abnormalities in chromosome behaviour in meiosis. The propagation of endosperm triploid seedless plants is in progress.     

A STUDY ON TUMOR FORMATION OF SOYBEAN AND GENE TRANSFER

From 15 strains of Agrobacterium tumefaciens 7 were selected as the best inductors oftumors on soybean and 94 tumor formation genotypes were screened from 1553 varieties andforms of Glycine soja, G. gracilis and G. max. The frequency of tumor formation was 6%.The bacteria-free calluses were obtained. The data of biochemical analysis verify that someof the above-mentioned calluses contained nopaline. This means that Ti-plasmid of Agrobac-terium tumefaciens can be used as a vector for the transfer of nopaline, a marker gene, intogenome of several species of soybean. In the soybean genome the transferred nopaline genewas integrated and expressed. The transformed gene can be stably integrated in the soybeangenome through vegetative propagation.     

EXPRESSION OF A ZEIN GENE (Z4) INTRODUCED INTO DICOTYLEDONOUS Solanum nigrum

A maize genomic clone containing a zein gene (Z4) is inserted into the T-DNA of the Ti plasmid pTiT37. Agrobacterium tumefaciens strain harboring this modified Ti plasmid is used to infect stem sections of young plants or explants of dicotyledonous Solanum nigrum. Axenic transformed calli active in nopaline synthesis are obtained and transgenic plants are differentiated from them DNA Southern hybridization and RNA dot-hybridization analyses show that the zein gene is really transferred and integrated into the nuclear genome of transformed Solanum nigrum and that the zein gene can be transcribed into mRNA in the transformed calli and shoots. But the presence of the zein protein cannot be detected in either the transformed calli or the transgenic shoots. The results of thte experiments demonstrate that the promoter of a gene from monocotyledonous plants can function normally in transgenic dicots. The possibility of developmentally-regulated expression of the zein gene in transformed dicots is discussed in     

大豆致瘤及基因转移研究

本文报道了致瘤农杆菌(Agrobacterium tumefaciens)的15个菌系对大豆的致瘤作用,筛选出致瘤效果较好的7个菌系.从野生大豆、半野生大豆和栽培大豆的1553个品种和品系中筛选出94个结瘤品种和品系,占筛选总数的6%,并获得了无菌愈伤组织.经生化鉴定证明,上述愈伤组织中有一部分含有胭脂碱(nopaline),证明Ti质粒可以做为载体,把胭脂碱基因转移到野生大豆、半野生大豆和栽培大豆的基因组中去整合和表达,并稳定地保存在大豆基因组中。     

ESTABLISHMENT OF T-DNA-CONTAINING SOYBEAN CELL LINES

This paper reports establishment of stable diploid cell lines containing nopaline synthase genes from callus containing T-DNA after 65 generations of successive suspension cultures. The strain C_(58) Agrobacterium tumefaciens was used for tumor inducing on variety "Siyuchuang". The T-DNA-containing tissue was separated in auxin-free MS medium by strictly screening three times from single cells. The presence of nopaline was identified by paper electrophoresis. The T-DNA-containing polyploid soybean cell lines were obtained at the same time. The nopaline synthase genes from T-DNA were stably integrated and expressed in soybean genome, which can be used in gene engineering with soybean.     

玉米醇溶蛋白基因Z_4在双子叶植物龙葵(Solanum nigrum)中的表达

本文将含有玉米醇溶蛋白基因Z_4的玉米基因组克隆插入Ti质粒pTiT_(37)的T-DNA区。用带有此质粒的根癌农杆菌感染龙葵,得到了能合成胭脂碱的转化愈伤组织和转化植株。DNA分子杂交和RNA点杂交表明,Z_4基因确实转化并整合进了龙葵的核基因组,并且被转录成mRNA。但在转化体中,没能检测出玉米醇溶蛋白。实验证明,单子叶植物基因的启动子能够在双子叶植物中发挥功能。文中讨论了Z_4基因在双子叶转化植物的种子中受发育调节的可能性。     

大豆(Glycine max(L.)Merr.)未成熟子叶组织的体细胞胚胎诱导和植株再生的研究

本文利用大豆未成熟子叶作外植体,进行大豆体外培养并诱导体细胞胚胎形成和植株再生的研究。结果表明,高浓度生长素10mg/l NAA或5mg/l 2,4-D是大豆体细胞胚胎形成的先决条件。附加10mg/1 NAA的Murashige和Skoog培养基(简称MS培养基)能够直接在子叶表面诱导体细胞胚的形成,其频率可达85％;附加5mg/l 2,4-D的MS培养基首先诱导未成熟子叶产生胚性愈伤组织,然后产生大量体细胞胚,频率高达94％。我们成功地获得再生的大豆完整小植株15株,消除了大豆基因工程的障碍之一。     

含T-DNA大豆细胞系的建立

本文报道了由致瘤农杆菌(Agrobacterium tumefaciens)C58菌株诱发的栽培大豆“四月黄”品种的瘤组织,经过无激素的MS培养基初步筛选和标记基因产物胭脂碱纸上电泳鉴定,筛选出含T-DNA的大豆愈伤组织。经过65代悬浮继代培养以及三次单细胞筛选,成功地获得了含T-DNA的稳定的大豆细胞系。同时还建立了一个含有T-DNA的多倍体细胞系。异源的T-DNA中的胭脂碱合成酶基因在大豆细胞基因组中稳定的整合和表达。为大豆的基因工程研究创造了良好的条件。