萼翅藤访花昆虫的研究

于2016年3月对云南铜壁关国家级自然保护区内萼翅藤(Calycopteris floribunda(Roxb.)Lam.)的访花昆虫的种类、访花频率、停留时间等进行了观测。结果表明:萼翅藤访花昆虫仅有9种,分属于鳞翅目、膜翅目、双翅目、缺翅目;大多数昆虫的访花频率均小于5朵次,且停留时间均不超过80 s;温度高于25.5℃或低于18℃,几乎会使访花昆虫停止活动。访花昆虫种类少、访花频率低、停留时间短是导致萼翅藤濒危的主要因素。     

Cloning and Functional Analysis of Lycopene ε-Cyclase （lbL C Ye） Gene from Sweetpotato, Ipomoea batatas （L.） Lam.

This paper reported firstly successful cloning of lycopene ε-cyclase(IbLCYe) gene from sweetpotato,Ipomoea batatas(L.) Lam.Using rapid amplification of cDNA ends(RACE),IbLCYe gene was cloned from sweetpotato cv.Nongdafu 14 with high carotenoid content.The 1 805 bp cDNA sequence of IbLCYe gene contained a 1 236 bp open reading frame(ORF) encoding a 411 amino acids polypeptide with a molecular weight of 47 kDa and an isoelectric point(pI) of 6.95.IbLCYe protein contained one potential lycopene ε-cyclase domain and one potential FAD(flavinadenine dinucleotide)/NAD(P)(nicotinamide adenine dinucleotide phosphate)-binding domain,indicating that this protein shares the typical characteristics of LCYe proteins.The gDNA of IbLCYe gene was 4 029 bp and deduced to contain 5 introns and 6 exons.Real-time quantitative PCR analysis revealed that the expression level of IbLCYe gene was significantly higher in the storage roots of Nongdafu 14 than those in the leaves and stems.Transgenic tobacco(cv.Wisconsin 38) expressing IbLCYe gene accumulated significantly more β-carotene compared to the untransformed control plants.These results showed that IbLCYe gene has an important function for the accumulation of carotenoids of sweetpotato.     

枣结果枝核糖体蛋白的生物信息学分析

应用生物信息学的方法对枣(Ziziphus jujuba Mill.)生长初期结果枝的cDNA文库ESTs进行了功能注释,查找核糖体蛋白基因,并对其氨基酸序列组成、基本理化性质、蛋白质二级结构、疏水性/亲水性及潜在磷酸化位点等进行了初步分析预测,旨在了解其结构特征,进而发掘枣树的优良基因。结果表明,625个ESTs中,有397个ESTs与NCBI中已知功能基因相似性较高(其中重复ESTs 77个);将320条ESTs通过KEGG数据库进行代谢分析,得到123条ESTs的62个代谢途径。对获得的枣树24个核糖体蛋白进行分析发现,其分子量在6 931.12～32 764.44之间,α-螺旋和无规则卷曲是其主要的结构元件,多肽链都表现为亲水性,磷酸化潜在位点普遍存在于核糖体蛋白多肽链中;并构建了24个核糖体蛋白的进化树,对其分子进化进行了探讨。     

NaCl和PEG6000胁迫下枣组培苗中ZjAPX的表达

为了探索枣树遭遇盐、干旱胁迫时抗坏血酸过氧化物酶基因(ZjAPX)在抗氧化系统中的响应,以枣树组织培养植株为试材,进行了NaCl和PEG6000(模拟干旱)胁迫,观察受胁迫后植株外观形态变化,并从植株叶片中提取RNA进行反转录。根据ZjAPX的cDNA序列设计特异性引物,以反转录产物为模板,对ZjAPX基因在胁迫条件下的表达情况进行了定量分析。结果表明,ZjAPX基因受NaCl和PEG6000诱导表达,而且在一定浓度和时间范围内,随着浓度的增大和胁迫时间的延长表达量增高,说明ZjAPX基因参与了植株抵抗盐和干旱带来的伤害。     

树干注射铁肥对新疆灰枣产量和品质的影响

采用树干注射的方式在灰枣的萌芽期、花期和果实生长期增施铁肥,并对树体的生长指标、产量和营养物质含量进行测定。结果显示：不同生长期增施铁肥对灰枣生长的促进作用都以萌芽期施肥处理Fe-2（3.0 g/株）最优,其干径增长量、基径增长量、枣吊增长量、单果质量和产量分别是对照的1.27、1.32、1.21、1.5和1.19倍;枣果铁、锰、锌和钙的含量分别是对照的1.63、1.44、1.04和1.24倍,糖酸比为56.02。在灰枣生长季节,采用树杆注射方式增施一定含量的铁肥,不仅能促进树体的生长,对其营养品质提高也有一定的作用。     

应用AFLP标记分析枣品种亲缘关系

从分子水平研究宁夏红枣品种系统发育和亲缘关系,为宁夏枣种质资源的保护和利用提供科学依据。利用AFLP标记方法对原产宁夏地区7个枣品种和6个从区外引种的枣品种基因组DNA进行分析。筛选出的5对AFLP引物组合对13个供试材料共扩增出351条DNA带,其中301条为多态带(占85.75%),平均每个引物扩增多态性带70条。13个材料间的遗传相似系数为0.376～0.957。UPGMA聚类表明,13个材料在相似系数0.85处被划分为5个类。宁夏地域相对狭小,品种交流频繁,从而造成该产区枣品种间亲缘关系较近,演化关系复杂。枣虽然品种资源丰富、分布范围广泛,但遗传多样性相对较小。     

‘苹果枣’自然三倍体倍性的发现与鉴定

 采用酶解去壁低渗法对枣品种‘苹果枣’进行了核型分析,其核型公式为：2n = 3x = 36 = 21m + 15sm（2SAT）,核型为2A 型,是迄今为止新发现的第2 个栆自然三倍体品种。对花粉母细胞减数 分裂观察结果表明,‘苹果枣’分裂不规则,终变期出现单价体、二价体和三价体,其中三价体约占57.5%, 最少含有7 个三价体,最多则含10 个三价体,3 个染色体组之间具有很高的同源性,后期Ⅰ和后期Ⅱ出 现落后染色体和染色体不均等分离现象;末期Ⅱ一些细胞还产生少数三分体及极少数五分体,形成不等 孢子,导致配子体高度不育,由此可判断‘苹果枣’为同源三倍体。用分子标记技术对‘苹果枣’和已 知的三倍体品种‘赞皇大枣’进行分子鉴定,两者分子指纹有显著差异,为不同的两个自然三倍体品种。     

Mycorrhiza and soil fertility effects with growth,nodulation and nitrogen fixation of leucaena grown on a typic eutrustox

Abstract

The rapidly growing, woody perennial legume, Leucaena (Leucaena leucocephala (Lam.) de Wit), is adaptable to a wide range of neotropical soil conditions. Effective Rhizobium inoculation and endophyte mycorrhizal colonization are essential for high levels of production and symbiotic N₂ fixation. The objective of this study was to determine growth, nodulation, nitrogenase activity and nodule composition of inoculated Leucaena as affected by mycorrhizal colonization and factorial soil fertility treatments of a Typic Eutrustox. Highly significant increases in top growth, nodule fresh wt. and nitrogenase activity resulted with Glomus fasciculatum colonization, soil K and linear increases with low‐soluble P fertilization to 300 mg P kg^‐1 soil. Highly significant interactions for increased nodulation and nitrogenase activity resulted with K × mycorrhiza. Interactions of all three factors P, K and mycorrhiza were highly significant for nodule fresh wt. However, responses comparing inoculation with G. fasciculatum and with combined G. fasciculatum, G. microcarpus and G. clavium were not significant. Highly significant increases with applied K levels to 300 mg K kg^‐1 soil resulted with top and root growth, nodulation and nitrogenase when applied with soluble P at 100 mg kg^‐1 soil and 500 mg Ca kg^‐1 soil. Significant and highly significant interactions of P, Ca and K level resulted for all parameters. Plant nutrient element composition of nodules increased with the fertilization treatments for P, Ca and increased K levels. A highly significant inverse relation was apparent with decreased Na resulting with increased K levels. Half or more of total nodule K, P and Mg but less than 20% of Ca and Na were within the nodule cytosol. Sodium, Mg, P, and Ca decreased in the cytosol fraction with increased K content.     

多花黑麦草(Lolium multiflorum Lam)籽粒收获适期的研究

1990～1992年对多花黑麦草(LoLium multiflorum Lam)俄勒岗品种的3个不同生长条件的群体进行了开花后当天至花后30天内的籽粒灌浆,脱落现象的研究,结果表明:3个群体的千粒重和脱落率与花后天数的关系均符合 Logistic 理论曲线.单穗籽粒干物重最大值出现在花后18～24天.花后15～18天的种子已具有较高发芽率(64.3%～91.1%),与以后各期收获的种子间无显著差异,但以花后18～24天的种子发芽苗质较好.据此.上海地区多花黑麦草种子的最佳收获期为花后18天～24天.     

枣树组织培养研究进展

概述了枣树的茎尖、芽和茎段培养、花药培养、原生质体培养、胚乳培养、离体叶培养等方面的主要进展,并针对枣树组织培养中存在的主要问题提出了今后的研究方向。快繁是枣树组培最成功的方面,以茎尖、芽或茎段为外植体已经建立了十几个品种的快繁体系,而且,应用茎尖培养和热处理相结合的方法得到了脱除枣疯病病原-植原体的无毒苗。应深入研究花药培养、原生质体培养、叶片培养、胚乳培养及胚培养,并尽快应用于枣树的转基因育种和倍性育种。特别是幼胚培养的研究应该进一步加强,从而解决因优良品种胚败育难以获得杂种后代的问题,实现枣树的杂交育种和遗传图谱的构建。