农田水位调控对水稻茎蘖动态和株高的影响

以稻田水位为调控指标进行水稻全生育期试验,研究了受涝、受旱和涝渍3种控水条件下水稻茎蘖数和株高的变化规律,并用SPSS软件进行模型拟合。结果表明,农田水位管理可以改变水位茎蘖数和株高的变化趋势,分蘖期内这2个指标对控水条件的敏感性最大,其次为拔节孕穗期。受涝、受旱、涝渍处理均不利于水稻茎蘖数和株高的增加,3种控水处理中...     

The Use of Stomatal Chloroplast Number for Rapid Determination of Ploidy Level in Maize

The usefulness of using the chloroplast number in epidermal guard cells as an indirect ploidy indicator was evaluated on seed-grown and tissue culture-derived maize plants. For seed-grown plants, two maize genotypes (B89 and R75) which had both diploid and tetraploid seeds available were used as experimental materials. The ploidy levels of seed-grown plants were confirmed by flow cytometric analysis of nuclear suspensions from these plants. For regenerated plants, haploid and diploid levels were examined and the ploidy levels of these plants were determined by chromosome counts of cells from root tips. A positive relationship between the chloroplast number and ploidy level was observed for both seed-grown and regenerated plants. The stomatal guard cells of tetraploid plants had nearly double the number of chloroplasts as the diploid plants. Similar results were found from the regenerated plants. The differences in the mean chloroplast number between diploid and tetraploid seed-grown plants and between haploid and diploid regenerated plants were highly significant. The results of this study demonstrate that counting chloroplasts in guard cells can be an efficient means of screening a large number of plants for ploidy levels. In addition, this study suggests the possibilities of using this method for detecting contaminated seed lots by different ploidy seed and for distinguishing plants of different genotypes.     

Efficient Production of Doubled Haploid Plants through Chromosome Doubling of Isolated Microspores in Brassica napus

Three methods of chromosome doubling to produce doubled haploid plants from microspore cultures of Brassica napus were compared: colchicine treatment of microspore-derived plants, microspore-derived embryos, and isolated microspores. In the whole plant treatment, 53% of the treated plants set seed, but the treatment delayed plant growth and reduced seed set. When microspore-derived embryos were treated with colchicine, the doubling frequency was 32% (compared to 15% for spontaneous doubling). Direct colchicine treatment of isolated microspores resulted in a doubling efficiency of 70 % of the whole plants. This treatment also stimulated embryogenesis in microspore culture, leading to increased plant regeneration. Thus, direct chromosome doubling of isolated microspores is efficient and more than 10 000 doubled haploid plants have been produced in this manner in the past three years in order to accelerate the plant-breeding process.     

烤烟井窖式移栽下不同密度和留叶数对质体色素及其降解产物含量的影响

为探讨烤烟井窖式移栽下烟株的适宜群体结构,提高烟叶品质,以烤烟品种云烟87为材料,采用田间试验,研究了井窖式移栽下不同密度和留叶数对烤烟质体色素及其降解产物含量的影响。结果表明:烤烟井窖式移栽下,密度、留叶数、密度×留叶数互作对质体色素及其降解产物含量均有显著影响。随密度降低,烤后烟叶叶绿素含量呈"V"形变化趋势,新植二烯、类胡萝卜素及其降解产物含量均呈先增加后降低的趋势;不同留叶数处理比较,叶绿素a、叶绿素b和叶绿素总量均表现为B3(24片/株)B1(18片/株)B2(22片/株),且B2处理叶绿素、类胡萝卜素降解产物含量均最高。不同密度与留叶数互作处理烤后烟叶叶绿素降解产物新植二烯含量和类胡卜素降解产物总量均以A2B2[密度16 675株/hm~2(行株距100 cm×60 cm)+留叶数22片/株]最高,分别为1 095.15μg/g和69.561 7μg/g,占挥发性香气物质总量的89.29%和5.67%。综合分析,井窖式移栽下,密度16 675株/hm~2(行株距100 cm×60 cm)+留叶数22片/株的群体结构有利于提高烟叶品质。     

新疆褐牛乳中体细胞数与产奶性状的影响因素分析

【目的】分析影响新疆褐牛乳中体细胞数（SCC）与产奶性状的非遗传因素,为有效指导并提高新疆褐牛的生产性能提供科学依据。【方法】构建协方差分析模型,利用SAS 9.2软件分析不同场、胎次、泌乳月及两两间互作效应等非遗传因素对262头新疆褐牛SCC与产奶性状的影响,并阐述各性状间的相互影响关系;采用Excel 2 013对新疆褐牛1 510条DHI数据进行整理,利用相邻两月SCC差值等级划分方法,绘制了不同牛场SCC变化趋势及其与产奶性状间的变化规律。【结果】场和胎次对新疆褐牛SCC及产奶性状均有极显著影响（P＜0.01）;泌乳月效应对产奶量和乳中SCC影响极显著（P＜0.01）,对乳糖率有显著影响（P＜0.05）,对其它乳成分无显著影响（P＞0.05）;不同场、胎次、泌乳月两两间互作效应对新疆褐牛SCC均无显著影响（P＞0.05）,而场和胎次互作效应对产奶量和乳成分有极显著影响（P＜0.01）,场和泌乳月互作对乳脂率和乳中干物质有极显著影响（P＜0.01）,对乳糖率有显著影响（P＜0.05）,对其它性状无显著影响（P＞0.05）;胎次和泌乳月互作效应对新疆褐牛各产奶性状均无显著影响（P＞0.05）。随着新疆褐牛乳中SCC增加,乳中干物质含量增加,而产奶量、乳脂率、乳蛋白率和乳糖率下降;绘制泌乳期SCC差值与产奶量和乳糖率变化曲线发现,随着SCC差值升高,产奶量及乳糖率均降低,表明使用SCC差值等级法能够有效评价奶牛产奶量变化并及时判定奶牛乳房炎的发病趋势。通过比较新疆褐牛两个牛场的产奶量、乳成分以及SCC控制情况,发现二号牛场各性状均优于一号牛场,其产奶量较高、SCC较低,且不同胎次水平的乳脂率、乳糖率及乳中干物质均较高,体现较好的生产管理水平。【结论】针对新疆褐牛非遗传因素的研究表明,为有效提高和改善该乳肉兼用牛品种的产奶性能和奶品质,应着力改善牛场管理水平、优化环境卫生及规范挤奶设备等;一号牛场应加强生产管理水平和DHI监测记录,通过控制新疆褐牛SCC来降低和避免泌乳牛的乳房炎隐患。     

家蚕性染色体和性别决定

家蚕是重要的经济昆虫和鳞翅目昆虫的典型代表,由于生产上专养雄蚕和农业害虫防治有极好的发展前景,对其性别决定机制的研究极为迫切.对家蚕的性染色体及其结构特征和性别调控相关基因的研究现状进行了综述.     

胶园单位面积有效割株变化及其原因分析

搜集了近年来我国植胶生产上的相关资料,在此基础上,初步分析了橡胶树种植密度、单位面积定植株数、有效割株数、有效存株率和存株类型的变化情况,以及胶园单位面积有效割株对胶园土地产出能力的影响及其原因,提出了提高我国胶园有效存株的建议。     

版纳微型猪近交系性别决定基因（SRY）原核表达载体的构建及蛋白高效表达

 为了构建版纳微型猪近交系SRY的原核表达载体pET 32a(+) SRY,并通过诱导使其在大肠杆菌中获得高效表达,研究采用添加限制性内切酶位点的引物特异性扩增SRY,连入pMD19 T simple载体,转化入大肠杆菌DH5α,克隆后提取pMD19 T SRY阳性重组质粒,使用相同的内切酶同时对pMD19 T SRY质粒和原核表达pET 32a（+）载体进行酶切,连接后使SRY定向克隆到pET 32a(+)表达载体中。经PCR、酶切和测序鉴定后,重组质粒转化大肠杆菌感受态DH5α,提取质粒后再次转化大肠杆菌Rosetta（DE3）,用不同浓度的异丙基硫代半乳糖苷（IPTG）诱导表达,并通过15% SDS PAGE鉴定。结果显示,不同浓度IPTG诱导的SRY均在大肠杆菌中进行了高效特异性融合表达。     

一些山茶属(Camellia L.)植物的细胞染色体研究

本文研究了我国原产的山茶属植物东兴金花茶(Camellia tunghinensis chang.)、平果金花茶(C.Pingguoensis D.Fang),毛籽金花茶(C.ptilos perma S.Y.Liang et Q.D.Chen)、凹脉金花茶(C.impressifZeruis Chang et S.Y.Liang)、金花茶(C.chrgsantha(Hu)Tugama)、毛瓣金花茶(C.pubipetala Y.Wan et S.Z.Huang)、小果金花茶(C.chrgsantha var.microcarpa S.L.M et S.Z.Huang)、广宁红花油茶(C.semiserrata C.W.Chi)、苑田红花油茶(C.polyodonta Chun et How)、腾冲红花油茶(C.riticulata f.simplex)、五宝山茶(C.japonica L.‘Wabao’)、云南大叶茶(C.sinrnsis var macrophylla Sieb.)、共12个种、变种和品种的染色体数目。除腾冲红花油茶2n=90外,其余的2n=30,并研究了其中3个种、变种和品种的核型:毛瓣金花茶为2n=2x=30=26m(2SAT)+4sm;小果金花茶为2n=2x=30=24m(2SAT)+6sm,五宝山茶为2n=2x=30=24m(2SAT)+6sm(2SAT) 7个种、变种和品种的染色体数目和其中3个核型为首次报道。     

小蚌兰的核型分析

采用染色体压片技术对小蚌兰进行染色体数目和核型分析。结果表明：小蚌兰体细胞染色体较小,染色体数目是2n=64;核型公式为2n=2X32m＋28sm＋4st,染色体相对长度组成为2n：64=12L＋18M2＋20M,＋14S．核型分类为2B型。