膏桐组织培养的初步研究

 通过不同激素配比诱导膏桐外植体产生愈伤组织,为利用愈伤组织进行离体快繁和膏桐转基因及生物工程育种奠定基础。结果表明：诱导膏桐子叶产生愈伤组织的最佳培养基是MS+2,4-D 2.0mg/L和 MS+6-BA 2.0mg/L+NAA 2.0 mg/L;诱导愈伤组织形成芽的最佳培养基为：MS+6-BA 2.5 mg/L+IBA 0.1mg/L;根的形成不需添加任何激素。适当的激素配比可有效诱导膏桐子叶产生愈伤组织并形成再生植株.     

小麦白斑突变体I30的特征特性及遗传分析

类病斑突变体是研究植物程序性死亡和抗病性的理想材料。为了丰富小麦斑点突变体的研究,对叠氮化钠诱变小麦品种陕农33产生的稳定遗传的白斑突变体I30进行了特征特性研究和遗传分析。结果表明,突变体I30从三叶期开始表现白色块斑和长条纹。锥虫蓝染色和DAB染色显示,I30斑点处出现细胞死亡和H_2O_2积累现象。透射电子显微镜观察表明,I30的叶绿体形状发生改变,数目减少,基粒垛叠高度无序,部分甚至降解。农艺性状调查结果表明,I30的株高、单株有效穗数、穗粒数、穗长和结实率与野生型间无显著差异,但千粒重、穗粒重、单株产量、旗叶长度和宽度显著低于野生型。遗传分析表明,I30由1对隐性核基因控制。利用BSA+660K基因芯片技术,将该基因定位于小麦6D染色体上,位于SSR分子标记Xcfd190和6DS-5之间,遗传距离分别为6.4cM和9.1cM。     

Sampling Survey and Identification of Races of Soybean Cyst Nematode (Heterodera glycines Ichinohe) in Huang-Huai Valleys

Soybean cyst nematode (SCN Heterodera glycines Ichinohe) is one of the most important nationwide soybean diseases in China. A total of 38 soil specimens or locations in the area was sampled and tested for SCN races during 2001-2003 for the inspection of race distribution in Huang-Huai Valleys. A map of race distribution was constructed according to the data from both the present study and the published reports cited. Three areas, namely, the area of southeast to Jinan in Shangdong Province; the area of northern Henan Province and its border region to south of Hebei Province; and the area of Luohe, Zhoukou of Henan Province and Fuyang of Anhui Province mainly infested with Race 1 were identified. Race 4 was predominant in Shanxi Province, Beijing and the adjacent area of Henan, Shandong, and Anhui provinces, and the delta of Huanghe River in Shandong Province. Race 2 was mainly found in Liaocheng, Dezhou of Shangdong Province and Shijiazhuang of Hebei Province, and Jiaozuo and Huojia of Henan Province. Race 7 was distributed in the west part of Jiaodong Peninsula of Shandong Province and Kaifeng, Huaxian, Wenxian of Henan Province. Race 5 was found and scattered in Hebei and Henan Province. Race 9 was found in Shangqiu of Henan Province, which was reported for the first time in China. It can be seen that Race 1 and Race 4 were the two predominant races in Huang-Huai Valleys, and that research should focus on developing resistant cultivars of these races. There might exist other races in an area with some predominant races. The race substitution in the past decade was not obviously found, therefore, the results should be meaningful to future breeding for resistance to SCN in Huang-Huai Valleys.     

侵染胡椒的黄瓜花叶病毒海南分离物全序列分析及亚组鉴定

对侵染海南胡椒的3个黄瓜花叶病毒分离物(CMV-WN1,CMV-DA,CMV-FT)的全序进行克隆和分析。CMV-WN1,CMV-DA,CMV-FT分离物RNA1全长分别为3 361,3 360,3 359个核苷酸(nt),编码1a蛋白;RNA2全长分别为3 044,3 048,3 046 nt,编码2a和2b蛋白;RNA3全长分别为2 217,2 224,2 216 nt,编码3a和CP蛋白。序列一致性比较结果表明,CMV-WN1,CMV-DA,CMV-FT的RNA1,RNA2,RNA3均与CMV亚组IB CMV-SD序列一致性最高,编码的所有蛋白的氨基酸序列一致性也均与CMV-SD序列一致性最高,其中除了2b氨基酸序列一致性低于90%外,其他蛋白的氨基酸序列的一致性均高于93.5%。RNA3的5'NTR结构分析以及RNA3 5'NTR核苷酸序列和CP氨基酸序列系统进化树分析结果表明CMV-WN1,CMV-DA及CMV-FT均属CMV IB亚组。CP系统进化树中CMV-WN1,CMV-FT与云南胡椒分离物CMV-YNP聚成一簇,而CMV-DA与海南胡椒分离物CMV-HNP独立形成另一个分支。     

京郊西兰花小菜蛾的田间防治药剂筛选与评价

为评价高效氯氰菊酯、溴氰虫酰胺、苏云金杆菌、甲氨基阿维菌素苯甲酸盐、乙基多杀菌素等5种杀虫剂对小菜蛾的田间药效,本文采用喷雾法进行了田间试验。结果表明,10%溴氰虫酰胺可分散油悬浮剂、6%乙基多杀菌素悬浮剂对小菜蛾在药后1~7 d的防效较好;32000 IU/mg苏云金杆菌可湿性粉剂、32000 IU/mg苏云金杆菌可湿性粉剂与10%溴氰虫酰胺可分散油悬浮剂分别按50%推荐用量组成的1∶1的混配剂,药后1 d的防效仅在60%左右,速效性较差,但是药后3~7 d的防效较好。其中,混配剂药后3 d的防效高达90.70%。5%甲氨基阿维菌素苯甲酸盐水分散粒剂和4.5%高效氯氰菊酯乳油在药后1~7 d的防效均较差。因此,在西兰花生产上可使用减量的溴氰虫酰胺与苏云金杆菌混配剂进行小菜蛾的防治,以达到农药减量增效防治小菜蛾的目的;在小菜蛾暴发时,可使用溴氰虫酰胺或乙基多杀菌素,以达到迅速防治的目的。     

水稻吸收、运输锌及其籽粒富集锌的机制

 锌是人体必需而又易缺乏的营养元素。在粮食作物可食部位生物强化锌被认为是解决人体缺锌的最有潜力的途径。水稻根吸收锌可分为分泌麦根酸等根系分泌物将土壤颗粒中的金属离子活化和重金属转运蛋白把锌离子转运进植株根部两个过程,ZIP家族基因在后一过程中发挥重要作用。水稻锌在木质部中运输主要以离子态为主,也可同有机酸、尼克酰胺等配体协同运输。地上部锌通过韧皮部再转运到新生组织或装载进入籽粒,水稻韧皮部再转运能力是影响籽粒富锌的关键因素,而锌大量累积在糊粉层中或与植酸等结合后,大大降低了锌的生物有效性。研究粮食作物籽粒富锌机制,利用现代分子生物技术生物强化籽粒中的锌含量,对满足人类锌营养健康具有重要意义。综述了锌在植物体内的生理功能,水稻对锌的吸收、运输和再转运,锌装载进入籽粒,锌在植物体内的分布与赋存形态,以及锌在粮食作物中的生物强化等最新研究进展。     

可可种质资源多样性与创新利用研究进展

就可可种质资源在起源、分布、传播、分类、鉴定及种质创新与利用等方面取得的研究进展进行综述。可可属植物有22种,仅可可(Theobroma cacao)和大花可可(Theobroma grandiflorum)用于栽培。可可种质资源多样性丰富,其分类研究经历了传统形态学划分的Criollo、Forastero和Trinitario遗传类群到现代分子标记划分的Maran~on、Curaray、Criollo、Iquitos、Nanay、Contamana、Amelonado、Purús、Nacional和Guiana遗传类群。目前,可可的生产性品种选育仍以实生选种和芽变选种为主。分子标记的开发、遗传连锁图谱的构建和全基因组测序的完成,为实现可可分子标记辅助育种提供了技术保障。     

硼肥不同施用方法对油菜生长及产量的影响

针对洞庭湖地区油菜常规施硼（叶面喷施）效果不稳定的问题,于2004~2005年在沅江市北部垸田区进行了油菜不同施硼方法的试验。结果表明,硼肥基施加叶面喷施比单纯叶面喷施效果更佳,以基施7 500 g/hm2＋喷施1 500 g/hm2增产效果最好,经济效益最高,可在生产上推广应用。     

Cloning and Characterization of a Salt Tolerance-Associated Gene Encoding Trehalose-6-Phosphate Synthase in Sweetpotato

Trehalose plays an important role in metabolic regulation and abiotic stress tolerance in a variety of organisms. In plants, its biosynthesis is catalyzed by two key enzymes： trehalose-6-phosphate synthase（TPS） and trehalose-6-phosphate phosphatase（TPP）. In the present study, a TPS gene, named IbTPS, was first isolated from sweetpotato（Ipomoea batatas（L.） Lam.） cv. Lushu 3 by rapid amplification of cDNA ends（RACE）. The open reading frame（ORF） contained 2 580 nucleotides encoding 859 amino acids with a molecular weight of 97.433 kDa and an isoelectric point（pI） of 5.7. The deduced amino acid sequence showed high identities with TPS of other plants. Real-time quantitative PCR analysis revealed that the expression level of IbTPS gene was significantly higher in stems of Lushu 3 than in its leaves and roots. Subcellular localization analysis in onion epidermal cells indicated that IbTPS gene was located in the nucleus. Transgenic tobacco（cv. Wisconsin 38） plants over-expressing IbTPS gene exhibited significantly higher salt tolerance compared with the control plant. Trehalose and proline content was found to be significantly more accumulated in transgenic tobacco plants than in the wild-type and several stress tolerance related genes were up-regulated. These results suggest that IbTPS gene may enhance salt tolerance of plants by increasing the amount of treahalose and proline and regulating the expression of stress tolerance related genes.