Genetic Transformation of Brassica campestris L. ssp.pekinensis via Agrobacterium－ with Bt Gene

By means of Agrobacterium-mediated transformation, 43 kanamycin-resistant buds of Chinese cabbage were got. PCR, PCR-Southern blot and dot blot analysis were used to identify and characterize the putative transgenic plants. 26 plants had the predicted bands of the fragment of npt Ⅱ gene. Insect bioassays of 4 transformants showed that toxic protein had been translated and the translation levels were different among these transformants.     

Directional Breeding of An Oval-ecotype Male Sterile Line of Chinese Cabbage(Brassica campestris L. ssp. pekinensis)

[目的]探究大白菜定向转育卵圆生态型雄性不育系的方法。[方法]以大白菜核不育＂复等位基因遗传假说＂为理论依据,以甲型两用系‘AB12’为不育供体品系,以卵圆生态型可育品系‘06048’为待转育品系,采用杂交、回交、兄妹交和测交的方法,按照定向转育方案将核不育基因定向转育。[结果]各世代育性分离比率与理论相一致,成功育成了一种不育株率100%的具有‘06048’园艺性状的新核不育系,实现了核不育基因和园艺特性的同时转育。[结论]该研究成果验证此定向转育方案是可行的,进一步为基因型为 msms的其他园艺性状的大白菜定向转育提供理论基础,也可以推广应用到整个芸薹属其它经济作物中,极大的拓宽了优良核不育基因的实际应用范围。     

Identification of QTLs Related to Bolting in Brassica rapa ssp. pekinensis （syn. Brassica campestris ssp. pekinensis）

A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individuals were derived from F1 which was developed by crossing a bolting resistant DH line Y-177-12 and an easy bolting DH line Y195-93a. AFLPs were generated by the use of restriction enzymes EcoR Ⅰ and Mse Ⅰ . The segregation of each marker and linkage was analyzed by using JoinMap version 3.0. Mapped markers were aligned in ten linkage groups which covered 887.8 cM with an average marker interval of 4.47 cM. Markers showing skewed segregation ratio were clustered in six LGs. Quantitative trait loci （QTL） were mapped for bolting resistance by using MAPQTL 4.0 package. Four QTLs explaining from 7.0 to 9.4% of the total variation were detected, all of them increase bolting resistance. These mapped QTLs could be used to develop a marker assisted selection programme for bolting resistance breeding.     

Cytological Observation of Microsporogenesis in Male-Sterile Lines of Chinese Pink （ Dianthus chinensis L.）

This study addressed the differences in microsporogenesis between male sterile and fertile lines of Chinese pink. The microsporogenesis processes of male sterile and fertile lines were histologically examined in squashed pollen grains and in paraffin embedded sections. A stable male-sterile line （H-37B） was obtained following six generations of inbreeding in a self-fertile line, followed by two generations of backcrossing. In the corresponding fertile line, development of the mature pollen grains was followed through the initiation of the sporogenous cell, microsporocyte formation, and the tetrad developmental period. In the male-sterile line, abortion of the developing pollen grains was observed to take place at various stages, namely, sporogenous cell growth, mother cell meiosis, and tetrad transformation to the uninuclear state. The pollen grains of the fertile line were spheroid, turgid, and viable. By contrast, the male-sterile line produced pollen that was irregular in shape, empty, and nonviable. The abortion of the microspore in the male-sterile line appeared to relate to abnormal growth of the tapetum layer.     

Exogenous Nitric Oxide Alleviated the Inhibition of Photosynthesis and Antioxidant Enzyme Activities in Iron-Deficient Chinese Cabbage （Brassica chinensis L.）

The effects of exogenous nitric oxide （NO） on plant growth, chlorophyll contents, photosynthetic and chlorophyll fluorescence parameters as well as lipid peroxidation and activities of antioxidant enzymes were investigated in Chinese cabbage plants exposed to iron （Fe） deficiency. Iron deficiency led to serious chlorosis in Chinese cabbage leaves, and resulted in significant decrease in plant growth, photosynthetic pigments, net photosynthetic rate, Fv/Fm, Ф ps Ⅱ and activities of antioxidant enzymes, and increase in lipid peroxidation. While treatment with SNP, a NO donor, it could revert the iron deficiency symptoms, increased photosynthetic rate as well as activities of antioxidant enzymes, and protected membrane from lipid peroxidation, as a result, the growth inhibition of Chinese cabbage by Fe deficiency was alleviated.     

Monosomic Addition Lines of Flowering Chinese Cabbage (B. campestris L. ssp. chinensis var. parachinensis L. H. Bailey)-Chinese Kale (B. oleracea L. var. alboglabra L. H. Bailey)

Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition lines was conducted by karyotype analysis and morphological observation with the reference of parents. Triploid interspecies hybrid (AAC, 2n=3x=29) was obtained from Brassica campestris ssp. chinensis var. parachinensis Qinglu 9601 (tetraploid, AAAA, 2n=4x=40)×B. oleracea vat. alboglabra Baihua 9705 (diploid, CC, 2n=2x=18) by immature hybrid embryo culture in vitro. Five different alien monosomic addition lines (AA C2, AA C3, AA C4, AA C6, AA C7) were obtained from the backcross progenies of AAC×AA. Each alien monosomic addition line has some specific morphological characters. It is feasible to obtain alien addition lines from the progenies of AAC×AA by karyotype analysis and morphological observation based on the reference of parents.     

大白菜-结球甘蓝5号二体异附加系的选育及鉴定

【目的】获得稳定遗传的大白菜-结球甘蓝二体异附加系。【方法】以大白菜-结球甘蓝5号单体异附加系为材料,对其自交后代进行细胞学及SSR鉴定。【结果】37株自交后代中2n=22植株的比率为10.81%,通过对4个2n=22的植株进行核型分析及SSR鉴定,确定其为大白菜-结球甘蓝5号二体异附加系。减数分裂观察发现,大白菜-结球甘蓝5号二体异附加系后期Ⅰ虽然出现染色体落后现象,但在后期Ⅱ中染色体的分裂方式以11-11-11-11为主,其比率为69.55%。【结论】获得了大白菜-结球甘蓝5号二体异附加系,其外源染色体与甘蓝07连锁群相对应;该二体异附加系减数分裂形成的四分体以附加1条的染色体为主(n=11),有较高的遗传稳定性。二体异附加系的获得为研究芸薹属A、C基因组的亲缘关系,以及向大白菜中导入结球甘蓝的优良基因具有重要意义。     

广东菜心、芥蓝研究现状与展望

菜心和芥蓝是广东省重要的叶菜类蔬菜,具有种植面积大、复种指数高和市场需求量大的特点,其营养价值高,风味独特,已经成为人们日常饮食中必不可少的蔬菜种类。广东省是菜心和芥蓝秋冬季节的主产区。随着我国北方夏季种植区域的扩大,消费者对叶菜类蔬菜商品性和品质的需求提高,对现有品种的产量、适应性、抗性和风味物质含量等提出了新的要求。通过对种质资源的收集、保存和挖掘,广东省内各科研单位对菜心和芥蓝进行了大量的育种和分子生物学研究工作,促进了品种从常规种到杂交种的更替,也为未来分子育种打下了基础。而广东省菜心和芥蓝在实际生产中依然面临一些问题,需要从品种本身特性和挖掘优异种质资源上进行突破,利用现代生物技术与常规杂交育种技术相结合,提升品种在抗性、品质和适应性等方面的不足。综述了广东省菜心和芥蓝的研究历史、种质资源收集情况、分子生物学研究和产业发展现状,以期为广东省叶菜类蔬菜产业发展提供参考。     

大白菜-结球甘蓝双单体异附加系的SSR鉴定及其特性

 【目的】筛选大白菜-结球甘蓝异附加系,利用SSR标记鉴定附加的外源染色体,并对异附加系特性进行研究。【方法】以大白菜-结球甘蓝异源三倍体（AAC）与二倍体大白菜（AA）回交一代的自交后代为试材,利用根尖染色体计数、甘蓝连锁群特异SSR标记等方法,筛选、鉴定大白菜-结球甘蓝异附加系。【结果】在BC1F2中筛选到2n=22的植株;该植株对位于甘蓝01连锁群的3对SSR引物和08连锁群的2对SSR引物的扩增结果与异源三倍体杂交种是一致的,而对位于其它7个连锁群的20对特异引物的扩增结果与大白菜一致,表明该植株附加的外源染色体与甘蓝的01、08连锁群相对应,为双单体异附加系;该双单体异附加系绝大多数花粉母细胞减数分裂终变期染色体构型为10Ⅱ+2Ⅰ,后期Ⅰ以11-11、10-12分离方式为主,后期Ⅱ产生了n=11配子。【结论】利用甘蓝连锁群相对于大白菜特异的SSR标记可以准确鉴定大白菜-结球甘蓝异附加系;获得了附加甘蓝01、08连锁群的大白菜双单体异附加系,为进一步合成附加甘蓝01或08连锁群大白菜-结球甘蓝单体和双体异附加系奠定基础。     

菜薹-芥蓝单体异附加系n+1配子传递及两个二体异附加系的获得

【目的】研究菜薹-芥蓝单体异附加系n+1配子传递,为其在基因定位和遗传改良上的应用奠定基础。【方法】通过观察和统计各单体异附加系减数分裂后期Ⅱ10/10/11/11分离的PMCs,估算n+1配子的形成频率;通过鉴定回交子代植株的染色体数目,测定各单体异附加系n+1配子的传递率;从单体异附加系的自交子代中筛选二体异附加系。【结果】依据减数分裂后期Ⅱ10/10/11/11分离的PMCs比率估算,各单体异附加系n+1雄配子的形成频率在36.85%—45.15%;基于染色体数目鉴定,各单体异附加系n+1雄配子的传递率在7.14%—14.81%,雌配子在19.70%—36.51%;在一定范围内,n+1配子传递率与n+1配子形成频率、染色体大小、花粉量和花粉生活力没有显著的相关性;从自交子代中获得了两个不同的二体异附加系。【结论】菜薹-芥蓝各单体异附加系的额外染色体通过雌、雄配子均能进行传递,但传递率因不同的附加系而异;从单体异附加系的自交子代中可以分离出遗传性稳定的二体异附加系。     

菜心雄性不育两用系66A的选育与利用初报

从福州市地方菜心品种“七叶心”自交后代中发现不育株。经过一代测交 ,三代回交后 ,不育株率稳定在 5 0 %左右 ,获得雄性不育两用系 6 6A。用 6 6A与小白菜杂交 ,杂种一代的一般性状偏向小白菜 ,表现出较强的生长优势 ,尤其是可食用部分较父母本增长了 1～ 2倍 ;品质方面却偏向菜心 ,略带甜味 ,柔软可口     

人工合成的十个优良小麦种质系的细胞学和性状特点的研究

本试验对从八倍体小偃麦与普遍小麦的杂种后代中选出的10个优良小麦种质系,进行了细胞学和田间试验鉴定。结果表明,在这10个小麦种质系中,其中有2个品系为单体异附加系,1个品系为双单体异附加系,2个品系为双体异附加系。有5个品系染色体数目与普通小麦相同,但具有偃麦草的某些特点,细胞学上具有异常行为,它们可能为新的次生六倍体小麦。这些小麦种质系中,有的综合性状较好,具有较好的丰产性能,有希望在生产上直接加以利用;有的虽然综合表现欠佳,但具有突出特点,可作为种质材料在育种上利用。     

白菜细胞核雄性不育基因向菜心品种早-49的转育研究

根据大白菜复等位基因遗传假说,利用现有白菜雄性不育系(99029-2)作为不育源,以早-49菜心品种为目标亲本,经过杂交、自交、测交、兄妹交等转育方法,将核不育基因向菜心品种转育,得到了含有早-49遗传基因的新甲型两用系、临时保持系和雄性不育系。     

大白菜开花的温度反应特性研究

 以大白菜自交系03s205,03s206为试材,研究了温度对大白菜抽薹开花的影响。结果表明,随着2℃种子春化时间的延长,从播种到开花的时间缩短,叶片数减少。从春化开始到现蕾的总计天数来看,春化15 d的处理所需时间最短。而未经春化的对照处理则不能开花。在8℃和10℃条件下,03s205和03s206均能通过春化,但10℃条件下要求更长的持续时间。8℃处理15 d就可开花,而10℃处理要25 d才能通过春化。苗期35℃的持续高温可使春化15 d和24 d的材料发生春化逆转,但对苗龄大于12 d的植株无效。而18 h 23℃和6 h 35℃交替温度下,春化15 d的大白菜不发生春化逆转,仍能够开花。     

含磷物质对铅耐性与敏感性植物生长及磷铅吸收的影响

将耐性植物芥蓝(Brassica capitata)与敏感植物小白菜(Brassica chinensis)暴露于含Pb的营养液中,通过添加磷灰石矿尾料(PR)、重过磷酸钙(TSP)及二者混合物(P+T)处理,研究含磷物质对两种植物吸收Pb的影响以及Pb在植物根表面形态变化过程。结果显示:添加含磷物质降低了耐性植物芥蓝根部Pb的含量,但对地上部Pb吸收的影响不显著;对敏感植物小白菜来说,PR和P+T处理的植物根部及地上部Pb的含量与对照基本一致,而TSP处理促进了Pb的吸收,表现出小白菜根部及地上部Pb的含量显著高于对照组。含磷物质添加诱导了Pb在植物根表面形成Pb5(PO4)3Cl、Pb5(PO4)3OH的沉淀,但这并没有直接导致两种植物对Pb吸收量的减少。