桃花粉活性检测和离体萌发特性的研究

果树花粉活力直接影响授粉、受精乃至座果。为了解果树品种的花粉生活力,给引种栽培和杂交育种工作创造有利条件,以桃花粉为试验材料,采用染色方法检测花粉的活性。试验结果表明,含有蓝墨水的花粉培养基,花粉萌发率可以达到64.67%,与对照相比差异不明显,因此该方法比较适合于快速检测花粉活性;固体培养基培养2个品种桃花粉,萌发率比液体培养基培养分别高25%和20%。另外温度、花粉密度、培养基中蔗糖及硼酸浓度都对花粉萌发率和花粉管长度有影响,在温度为24℃、1粒花药/100 μL、10%的蔗糖或100 mg/L的硼酸的条件下,均有利于花粉萌发和花粉管生长。     

运用SRAP分子标记鉴定辣椒杂交种纯度

摘要：以辣椒品种航椒4号和航椒5号及其亲本H09-4、H09-2、WS-3、B-2-2为试验材料,运用SRAP分子标记技术研究了辣椒杂种与其亲本之间 扩增条带的多态性,鉴定和分析了航椒4号辣椒品种的真实性。结果表明,所试验的18对SRAP引物中有13对引物分别在2个辣椒杂交种和其亲本之间存在扩增条带的多态性,平均每个引物组合扩增的清晰条带数为23.5条,多态性比率为58.89%,其中有3条偏母型引物,2条偏父型引物, 2条互补型引物。用互补型引物DC1-EM9对航椒4号和航椒5号进行了各100粒种子SRAP鉴定,所测纯度分别为100%和97.3%,与田间纯度100%和98.9%非常接近,表明了SRAP分子标记技术是鉴定辣椒一代杂种纯度的有效方法,具有准确、可靠、快速的特点,在辣椒杂交种子纯度室内快速检测中有很大的应用前景。     

栝楼雌雄株形态、生理生化指标差异的研究

通过对栝楼雌雄株花器形态特征的观察,发现雌花子房在雌花分化初始即开始膨大,明显区别于雄花;18%的雌花中具有花药,但扫描电镜观察发现雌花花药中并不含有花粉,排除了其自花授粉的可能。花期雌雄株叶片在水溶性酚和可溶性糖含量上存在显著差异。通过对种子大小与性别的关系研究,发现同一批种子中,长成雄株的种子比例远高于长成雌株的种子比例,且种子重量与栝楼性别分化存在一定的相关性。研究结果对于筛选栝楼早期性别鉴定指标具有重要的参考价值。     

Root distribution patterns of peanut genotypes with different drought resistance levels under early‐season drought stress

Drought severely limits crop yield of peanut. Yet cultivars with enhanced root development enable the exploration of a greater volume of soil for water and nutrients, helping the plant survive. Root distribution patterns of three genotypes (ICGV 98305, ICGV 98324 and Tifton‐8) were compared when grown in well‐watered rhizoboxes and when grown in rhizoboxes where an early‐season drought was imposed using rain‐exclusion shelters. The treatments were arranged in a completely randomized design with three replications, and the experiment was conducted during two seasons at the Field Crop Research Station of Khon Kaen University, in Khon Kaen, Thailand. The root system of ICGV 98305, when grown under drought, had a significantly higher root length in the 30–110 cm deep soil layers and less roots in the 0–30 cm soil layers when under drought than when grown under well‐watered conditions. Roots of Tifton‐8 had the largest reductions in root length in upper soil layer and reduced in most soil layers. Tifton‐8 grown under drought was smaller than under well‐watered control for all root traits, showing negative response to drought. The peanut genotypes with high root traits in deeper soil layer under early‐season drought might contribute to drought avoidance mechanism.     

高丹草杂种及其亲本转录组SNP及等位基因特异性表达分析

为探究高丹草杂种及其亲本间单核苷酸变异与其杂种优势形成的关系, 以高丹草杂种及其亲本的根、茎和叶组织为试验材料, 采用Illumina Hiseq 2000进行转录组测序。对平均长度达58 122 160 bp的各测序样品序列信息进行检测后, 均检测到不少于58 000个SNP位点, 位于基因内的SNP个数显著多于位于基因间的SNP个数, SNP发生频率为1/741 bp, 平均转换颠换比为1.00∶1.53。在所有变异类型中, C/T和G/A发生频率最高。经过筛选得到198 (21%)个极显著偏向性等位基因表达偏向性SNP, 其中65%偏向父本白壳苏丹草, 并且很多在白壳苏丹草中具有高水平基因表达的转录本, 在高丹草杂种中的等位基因表达也偏向白壳苏丹草。在3种组织中, 分别有79%、78%和82%转录本的2个亲本等位基因表现出相对平衡的表达水平, 说明与顺式作用相比, 反式作用可能更多地影响了等位基因的特异性表达。选择6个极显著偏向性等位基因表达偏向性SNP-unigene进行qRT-PCR验证, 这些基因的差异基因表达模式与RNA-Seq分析结果一致。本研究采用Illumina 测序技术研究等位基因表达, 为高丹草杂种优势分析提供了依据, 也为其他饲草作物的相关研究提供了理论参考。     

动态规划理论在原条造材优化设计中的应用

应用动态规划的理论模型，并结合具体原条进行了优化设计，从而得最优的造材方案和原木的最高售价。     

Bicarbonate Had Greater Effects Than High pH on Inhibiting Root Growth of Zinc‐Inefficient Rice Genotype

Abstract

Effects of bicarbonate (10 mM as NaHCO₃) and high pH (pH 8 buffered with HEPES) separately on root growth and accumulation of organic acids in the roots of zinc (Zn)‐efficient (IR36) and Zn‐inefficient (IR26) rice genotypes (Oriza sativa L.) were investigated in this study. The results indicated that shoot dry matter yields were decreased more by bicarbonate than by high pH for the Zn‐inefficient genotype, but not affected for the Zn‐efficient genotype. Root dry weights, especially root length, was significantly decreased by bicarbonate and high pH treatments for the Zn‐inefficient genotype, whereas was considerably enhanced by only bicarbonate treatment for the Zn‐efficient rice genotype. The reduction in root growth of the Zn‐inefficient rice genotype and the enhancement of root length in the Zn‐efficient genotype were greater when plants grown with bicarbonate than with high pH treatment. Accumulation of malate, citrate, and fumarate in roots of the two genotypes increased considerably due to both high pH and bicarbonate treatments, but to a greater extent for the Zn‐inefficient than for the Zn‐efficient cultivars. After an 8‐day treatment, more organic acids accumulated in the roots of the Zn‐inefficient genotype (IR26) when plants grown with bicarbonate than at high pH, but this was not the case for the Zn‐efficient genotype. The influence of root growth by bicarbonate appeared to be one of the major factors for the sensitivity of rice genotypes to Zn deficiency in calcareous soils. The greater inhibitory effect of bicarbonate than high pH on root growth of the Zn‐inefficient genotype might result from an excessive accumulation and inefficient compartmentation of organic acids, particularly citrate and malate, in the root cells.     

微卫星标记在近交系及封闭群小鼠遗传质量检测中的初步应用

利用建立的小鼠微卫星检测方法,对来源于2个单位的近交系BALB/c小鼠和封闭群ICR小鼠进行了遗传分析,结果发现A单位BALB/c小鼠发生了遗传污染,有部分小鼠在部分微卫星位点发生了变异,而B单位BALB/c小鼠在所有的检测位点上的结果都与预期的BALB/c小鼠位点一致;对ICR 小鼠分析结果发现A单位ICR小鼠在22个位点的平均杂合度为0.379,平均多态信息量为0.308,属中度多态,B单位ICR小鼠的平均杂合度为0.287,平均多态信息量为0.227,属低度多态.结果表明微卫星标记可用于检测近交系小鼠的遗传质量,也可用于分析封闭群小鼠的遗传多态性,为一种有潜力的实验动物遗传学检测标记.     

Related Characteristics and Multivariate Analyses in the Evaluation of White Oat Aluminum Tolerance

Standard white oat genotypes were subjected to different methods and aluminum (Al) levels under hydroponic conditions to verify the relationship between plantlet characteristics and their Al tolerance using multivariate analyses. A completely randomized design with three replications was used, adopting three evaluation protocols: “complete nutrient solution” with 0, 8, 16, and 32 mg L^?1 of Al supplied as aluminum sulfate [Al₂(SO₄)₃·18H₂O]; “complete nutrient solution” with 0, 8, 16 and 32 mg L^?1 of Al supplied as aluminum chloride (Al₂Cl₃?6H₂O); and the “minimum nutrient solution” with 0, 1, 3, and 5 mg L^?1 of Al supplied as Al₂Cl₃?6H₂O. The performance of white oat plantlet genotypes subjected to excess Al in hydroponic conditions is greatly associated with root length, where the nutrient solution composition and the Al sources interfere in these associations. The study based on the joint analysis of characteristics at plantlet level does not allow an efficient discrimination of Al-tolerant and Al-sensitive white oat genotypes.     

RAPD标记在合浦珠母贝家系F1代的分离方式

对RAPD标记在合浦珠母贝F1代全同胞家系共27个样品中的分离方式进行了研究。从21条RAPD随机引物中筛选了8条引物用于扩增分析,结果共扩增出49个位点,其中正常位点47个(95.9%),异常位点2个(4.1%),即子代有扩增带而双亲无。47个正常位点中3个位点在F1中不分离(6.4%),44个位点发生分离(93.6%,即多态位点)。卡方检验表明,44个分离位点中32个符合孟德尔分离规律(72.7%),12个位点发生偏分离(27.3%)。符合孟德尔分离位点中按11分离位点占43.8%,31分离位点占56.2%,其中,父本特有标记、母本特有标记和双亲共有标记分别占28.2%,15.6%和56.2%,父本特有标记略多于母本特有标记。根据“双假测交”理论,11分离位点是构建F1代家系的作图位点。较高的11分离位点表明,利用RAPD标记构建合浦珠母贝遗传连锁图谱是可行的。