Quantitative Trait Loci Mapping of Leaf Morphological Traits and Chlorophyll Content in Cultivated Tetraploid Cotton

Genetic mapping provides a powerful tool for quantitative trait loci （QTL） analysis at the molecular level. A simple sequence repeat （SSR） genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton （Gossypium hirsutum L.） cultivars, namely TM-1 and Hai 7124 （G. barbadense L.）, were used to map and analyze QTL using the composite interval mapping （CIM） method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds （LOD）≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection （MAS） of these traits in tetraploid cotton breeding.     

硝酸盐供应对玉米侧根生长的影响

以两个玉米(Zea mays L.)自交系478和Wu312为研究材料,采用琼脂培养方法,研究不同浓度NO-3对侧根生长的影响.结果表明,在外部浓度0.01～1.0mmol/L范围内,NO-3供应能显著增加侧根的长度及根生物量.但当NO-3供应超过1.0 mmo1/L后,侧根长度开始下降.当NO-3供应分别在超过5.0(Wu312)与10(478)mmol/L后,侧根密度显著下降.在10 mmol/LNO-3下,Wu312的侧根生长几乎完全被抑制.而478在20 mmol/L时,侧根密度仍可达到其最大值的30%(主根)～50%(胚根).植株地上部全氮及硝酸盐含量随NO-3供应的增加而升高,二者与侧根长度、侧根密度及冠根比的数学函数关系相同.     

Spatial heterogeneity and population risk analysis of cotton bollworm, Helicoverpa armigera, in China

In this study, semivariance was used to quantitatively measure the spatial heterogeneity for the egg population of cotton bollworm during a growing season. The typical characteristic parameters of theoretical semivariance models against lag distances were applied to measure components of spatial heterogeneity： trend, range, spatial dependence, and the strength of spatial dependence. Then, kriging interpolation was used to evaluate the population risk of cotton bollworm exceeding economic thresholds. From early June through early September, the population densities were sampled 10 times in the study field. Results showed that the spatial patterns were related to population density. For its low-density population, the spatially heterogeneous trends were usually of spherical shapes; but for highdensity ones, the trends shifted to Gaussian shapes. The spatial dependence appeared at varied distances ranging from 52 meters to 936 meters, and the spatial dependence was in the range of 0.39-288.60, which changed with population densities. While having high heterogeneity, the strength of spatial dependence became much stronger. Results of population risk analysis showed that there was a high risk during its early stages, especially in mid-June. In August, population risk was so low that it did not need to be controlled.     

Ectopic Expression of the Pttknl Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm.

A novel knottedl-like homeobox （knox） gene, Pttknl （Populus tremulaxtremuloides knottedl）, isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.     

Pollen Morphology of Eight Genera of the Subtribe Mutisiinae Less. sensu Bremer （Compositae） from Asia

The pollen morphology of 28 species and one variety representing eight genera of the subtribe Mutisiinae Less. sensu Bremer （Compositae） was investigated by scanning electron microscopy （SEM） and light microscopy. The pollen grains are usually radically symmetrical, isopolar, and tricolporate. The shape varies from spheroidal to subprolate in equatorial view and is three-lobed circular in polar view. Based on exine sculpturing observed under SEM, the pollen grains can be divided into three types： （i） type Ⅰ, with macrogranulate sculpture; （ii） type Ⅱ, with a finely granulate sculpture; and （iii） type Ⅲ with spiny sculpture. The palynological data showed that the Macroclinidium Maxim. was remarkably distinguished from those of the other seven genera. The variation of pollen characteristics within the Mutisiinae in Asia is little at species level, but it proves some useful information for studying the relationships among genera and it has an important significance in further understanding the evolutionary history of Mutisiinae.     

小麦叶肉细胞原生质体中微管骨架的排列格局与[Ca2+]cyt的关系

以小麦叶肉细胞原生质体为材料,通过免疫荧光标记和Ca~(2 )荧光染料的装载并结合药物学试验,借助激光共聚焦扫描显微镜观察,探讨微管骨架和Ca~(2 )之间的内在联系。试验结果表明,[Ca~(2 )]_(cyt)的升高能够诱发微管骨架的解聚;而微管骨架的解聚也会促使胞外Ca~(2 )内流,进而造成[Ca~(2 )]_(cyt)的升高。     

Ca2+参与茉莉酸诱导蚕豆气孔关闭的信号转导

以Fluo-3AM为Ca~(2 )荧光探针,结合激光共聚焦扫描显微技术,观察到在处理后数十秒内,气孔关闭之前,茉莉酸(JA)可引起[Ca~(2 )]cyt的迅速上升;叶照和JA的前体物亚麻酸(LA)几乎不能引起[Ca~(2 )]cyt的明显变化;钙的螯合剂EGTA预处理可完全阻断JA诱导气孔关闭的效应,并且JA不再引起保卫细胞[Ca~(2 )]cyt增加;质膜Ca~(2 )通道的抑制剂硝苯吡啶(nifedipine,NIF)可减弱JA诱导气孔关闭的效应,也使JA诱导保卫细胞[Ca~(2 )]cyt增加的幅度有所下降;胞内Ca~(2 )释放的抑制剂钌红不能明显改变JA诱导气孔关闭的趋势,但使JA引起的保卫细胞[Ca~(2 )]cyt增加有所降低。实验结果表明:Ca~(2 )参与JA诱导气孔关闭的信号转导;推测JA引起的[Ca~(2 )]cyt升高可能主要来源于胞外,但不能完全排除胞内Ca~(2 )的释放。     

胡杨、灰叶胡杨果实空间分布及其数量特性的研究

胡杨、灰叶胡杨种间比较,果穗、种子在树冠上的垂直分布均表现为树冠上层最多,中层居中,下层最少,树冠南北侧相比较,南侧果穗量多于北侧.单果种子量在树冠各层次上差异不显著.胡杨单果重是灰叶胡杨的2.68倍,千粒重是灰叶胡杨的1.33倍,单果种子量是灰叶胡杨的2.14倍,单株种子量是灰叶胡杨的1.28倍,而单株果实量灰叶胡杨是胡杨的1.59倍.同一个种不同居群间比较,胡杨、灰叶胡杨均是单株果穗数和果穗果实数各居群间都存在差异,胡杨各居群间单果重、单果种子量差异不显著,而灰叶胡杨各居群间单果重及单果种子量差异极显著.表明胡杨在物质和能量上对后代的投资能力强于灰叶胡杨,生殖策略是通过较高的单果种子量来保证一定数量的单株种子量;而灰叶胡杨单果种子量较低,却是通过较高的单株果量来保证单株种子量,并且较小的种子占据空间生态位的潜能较胡杨占优势.     

传染性法氏囊病不同代次细胞毒免疫效果的研究

将从山东省东营分离到的1株传染性法氏囊病病毒(IBDV)野毒(暂命名IBDV SDDY株,经鉴定该株与IBDV STC株具有较高的同源性)经SPF鸡胚传代,然后转为细胞培养,取第20代、21代、25代毒,以1倍剂量(3000TCID50/0.2mL)和5倍剂量不同的免疫剂量,分别在7日龄、14日龄对商品代海蓝褐蛋鸡进行免疫,并于免疫前用IBD-ELISA试剂盒检测IBDV母源抗体水平,于35日龄用传染性法氏囊病病毒超强毒(very virulent Infectious Bursal Disease Virus,vvIBDV)GX 8/99攻毒,在攻毒前再次检测IBDV的抗体水平,攻毒后观察记录各分组鸡的致病率和死亡率,并计算免疫器官体重指数,观察免疫器官的组织损伤情况.试验结果表明3代毒都具有较高免疫原性,但是20代毒仍具有较大的毒性,7日龄接种会引起法氏囊的萎缩,造成持续的组织损伤;21代毒、25代毒保护率高,无免疫抑制,是比较理想的疫苗来源;7日龄免疫较14日龄免疫更易造成组织损伤和免疫抑制,14日龄免疫较为合适.     

乙肝病毒核心蛋白及核心颗粒的结构及功能研究进展

乙型肝炎是由嗜肝DNA病毒(Hepatitis B virus,HBV)引起的一种世界范围内的传染性疾病.受HBV慢性感染的人群罹患肝硬化和原发性肝细胞癌(Hepatocellular carcinoma,HCC)的相对危险性至少增加100倍,并最终导致死亡,给人们的健康造成极大的威胁和损害.鉴于此,世界上许多生物医学家早已把他们的研究目标集中到了乙肝病毒,以期弄清楚该病毒的基本结构,致病机理、免疫原性、免疫逃避和生化分子遗传规律等方面的问题.而近来在这些研究中,对乙肝核心抗原(HBcAg)结构、功能及免疫逃避机制的研究又成了引人注目的焦点.本文综合了近年来国内外对乙肝核心抗原(HBcAg)及其核衣壳和核心抗原缺失突变体的研究资料,从以下几个方面对该领域的研究作了较为深入的分析和概述.