甘蔗常用亲本及杂交组合家系评价

为评价我国甘蔗亲本的遗传特点和组合的选配效果,采用澳大利亚家系试验法,借助R软件估算亲本的遗传方差、一般配合力(GCA)和组合特殊配合力(SCA)。结果表明:锤度的遗传主要受母本加性基因效应所制约,蔗茎产量主要受母本加性基因效应和非加性基因效应所制约,株高、茎径和有效茎受父母本加性基因效应和非加性基因效应所制约。CP88-2143、ROC10、ROC26、桂糖00-122、粤糖00-318和云蔗99-113作母本,内江57-416、崖城93-26、粤糖91-976和粤糖00-319作父本杂交后代表现出高产高糖,可作为糖能兼用好亲本使用。根据组合特殊配合力效应(SCA),CP88-2143×粤糖00-319、ROC10×粤糖91-976、ROC26×崖城93-26、桂糖00-122×ROC22、粤糖91-976×ROC22、粤糖93-159×内江57-416和云蔗99-113×CP84-1198组合综合表现良好,可作为生产性杂交组合,加大力度使用。     

澳大利亚引进甘蔗花穗在中国育种潜力评价

为深入了解澳大利亚引进甘蔗杂交花穗在中国培育优良甘蔗新品种的潜力,以12个引进花穗和15个中国花穗为材料,采用家系评价法对有性杂交后代蔗茎产量、糖产量、株高、茎径、有效茎数和锤度6个重要性状的方差、遗传力、父母本一般配合力及组合特殊配合力进行研究。分析结果表明:(1)参试组合内中国杂交组合间多数性状差异不显著,且遗传力低;澳大利亚杂交组合间多数性状差异均较显著,且遗传力高;(2)澳大利亚杂交组合新植蔗与宿根蔗的糖产量、蔗茎产量、株高、有效茎数和锤度这5个性状父母本一般配合力及组合特殊配合力高于中国组合,但茎径配合力低于中国组合,12个组合中新植蔗有9个组合宿根蔗有10个组合的茎径特殊配合力为负值,多数属于细茎;(3)澳大利亚杂交组合后代材料产量及糖分较高,但茎径较细,不适合中国目前的种植制度,不能作为生产品种使用;(4)通过引进国外杂交组合花穗在国内培育出优良后代作亲本使用,为国内亲本融入新的优异血缘,有利于培育突破性甘蔗新品种。     

云南甘蔗细茎野生种82-114测交后代主要性状遗传分析

利用云南甘蔗细茎野生种82-114(简称:云割82-114)为父本,与甘蔗栽培原种、生产品种和含野生血缘F1等3类亲本进行测交.对后代锤度、茎径、株高、有效茎、蔗产量等5个主要数量性状进行方差、遗传力和配合力分析,结果表明:①组合后代锤度、茎径、株高、有效茎4个性状差异极显著;②组合后代锤度、茎径、株高、有效茎的遗传力表现较突出,均超89.0%;③3类组合中,栽培原种×云割82.114后代有效茎配合力表现明显的正效应,生产品种×云割82-114后代锤度、茎径、株高、蔗产量配合力有比较明显的正效应,舍野生血缘F1×云割82-114后代锤度、茎径、株高、有效茎、蔗产量等5个指标的配合力效应取向不明显.     

甘蔗野生种割手密远缘杂交后代品质性状的遗传研究

利用甘蔗品种Co419与野生种割手密云南75-1-2远缘杂交,ROC25与远缘杂交后代云野02-356进行回交,分别获得F1和BC1群体;利用R软件,分析了2个群体全部真实性后代品质性状的遗传表现.结果表明,杂交后代品质性状广义遗传力高,正态分布特性明显,品质性状间显著正相关;F1含糖量和纤维含量高于商业亲本,但甘蔗蔗糖分、蔗汁糖分、蔗汁锤度和简纯度等性状劣于商业亲本;BC1除含糖量高于双亲外,其他性状介于双亲之间,但主要性状均优于F1,后代性状恢复快.     

四川桤木7×7完全双列杂交种实、种苗性状的遗传效应分析

通过对四川桤木杂交子代果实、种子及种苗性状的分析,估算四川桤木亲本的遗传参数,为四川桤木杂交育种亲本选配提供理论依据。以7个优树作为杂交亲本,按7×7完全双列交配设计进行控制授粉,测定49个杂交组合的果实、种子及苗木性状。结果表明,49个杂交组合间的果实鲜重、种子千粒重、果长、种长等表型性状及苗高、地径均存在着极显著的差异(P0.001);果实鲜重、种子千粒重、果长、种长等表型性状的一般配合力(GCA)、特殊配合力(SCA)和反交效应差异(REC)也存在着极显著的差异(P0.001)。苗高和地径的GCA、SCA和REC也存在着极显著差异(P0.001)。苗高和地径的广义遗传力分别为37.06%和38.04%,狭义遗传力分别为17.47%和16.03%,表明在苗期阶段,苗木生长受环境效应的影响较大。种实性状的加性方差是非加性方差的1.34~11.79倍,主要受加性基因效应控制,非加性效应次之。而苗高和地径的非加性方差分别是加性方差的1.12和1.37倍,主要受非加性基因效应影响,加性效应次之。综合分析杂交子代GCA、SCA和REC效应值,确定JG6和JT4为优良亲本,从49个杂交组合中初选出4个组合(BZ6×JG6、BZ6×SW2、JT4×TT13和BZ6×QJ1)为优良杂交组合,其杂交子代苗高和地径分别实现20.47%~76.22%和5.07%~43.18%的遗传增益。     

冬小麦粒叶比杂种优势及遗传效应分析

用9个冬小麦品种按5×4不完全双列杂交设计组配20个杂交组合,对小麦粒叶比的杂种优势和遗传效应进行分析。结果表明,小麦粒叶比表现出一定的杂种优势;一般配合力和特殊配合力方差均达极显著水平,说明亲本的粒叶比差异及杂交互作均对F1代产生遗传差异,该试验中石6021、农大99260080等的一般配合力较大,石6021×农大99260080、鲁麦14×济南17等组合的特殊配合力较大,产生了较强的杂种优势;粒叶比遗传符合加性-显性遗传模型,但以加性效应为主,其遗传决定度达87.65%,狭义遗传力为64.71%;在高粒叶比品种选育上应重视高粒叶比亲本筛选利用和杂交后代的早代选择。     

甘蔗常用亲本及杂交组合经济育种值分析

【目的】为评价我国甘蔗亲本的遗传特点和组合的选配效果。【方法】采用澳大利亚家系试验法,借助R软件对35个家系F1群体的株高、茎径、有效茎、蔗茎产量、蔗糖分等5个主要数量性状进行经济育种值（EBV）分析。【结果】24个母本经济育种值变幅为-205.95～225.70元,有11个母本经济育种值为正值;18个父本经济育种值变幅为-23.54～30.23元,有8个父本经济育种值为正值;35个家系经济育种值变幅为-259.79～341.96元,有15个家系经济育种值为正值。【结论】24个母本中,ROC22、粤糖92-1287、内江03-218、ROC25、HOCP92-648等5个可作为生产性母本,建议加大力度使用。18父本中,崖城84-153、ROC22和粤糖00-319等3个亲本可作为生产性父本,建议加大力度使用。ROC22?崖城84-153、粤糖92-1287?粤糖00-319、内江03-218識OC22、ROC22?粤糖93-159、ROC25?粤糖93-159、桂糖00-122識OC22、崖城97-46識OC22和HoCP92-648識OC26等8个家系可作为生产性家系该批组合易选育出高经济效益的新品种,建议加大力度使用。     

甘蔗品质指标的通径分析和因子分析

应用通径分析和因子分析方法,对36个甘蔗品种（系）的11个品质指标数据进行分析。简单相关分析结果表明,甘蔗蔗糖分除了与蔗渣蒸煮液失水量没有显著相关外,与其他9个品质指标均有显著或极显著相关性。甘蔗纤维分与甘蔗出汁率、蔗汁折光锤度、蔗汁旋光读数、蔗汁直接转光度、蔗汁间接转光度和蔗渣含水量有极显著相关性,而与蔗渣蒸煮液失水量、蒸煮液的折光锤度和蒸煮液的旋光读数的相关性不显著。通径分析结果表明,甘蔗蔗糖分主要受甘蔗出汁率、蔗汁直接转光度、蔗汁间接转光度、蔗渣蒸煮液失水量和蒸煮液的旋光读数等5个指标影响较大,而甘蔗纤维分主要受甘蔗出汁率、蔗渣含水量、蔗渣蒸煮液失水量和蒸煮液的折光锤度等4个指标影响较大。因子分析结果表明,9个甘蔗品质指标可由4个主因子所代表。其特征值的累计贡献率迭94．30％。前3个主因子分别为蔗汁糖分指标因子、蔗渣糖分指标因子和蔗渣水分因子。其特征值的累计贡献率达83．06％,第4个主因子只有蔗渣蒸煮液失水量载荷值较大。     

甘蔗蔗汁品质性状的回归分析及模型

本文对47份不同甘蔗基因型的蔗汁品质性状进行简单回归和逐步回归分析.结果表明,蔗汁蔗糖分(Suc)与锤度(BX)、温度校正后锤度(BX′)、蔗汁旋光读数(0Z)以及转光度(pol)之间均呈线性回归,简单回归模型均达极显著水平(P＜0.01),决定系数(R2)分别为0.9393、0.9199、0.9861及0.9839.通过逐步回归分析和残差分析建立多重线性回归方程为Suc=0.05706 0.21488BX 0.181030Z,方差分析表明多重线性回归模型达极显著水平(P＜0.01),决定系数为0.9931.t测验表明,蔗汁蔗糖分的模型预测值与实测值间的差异不显著,相对误差平均为0.49%.     

西方蜜蜂王浆产量与品质性状的配合力和杂种优势分析

对蜜蜂杂种F18个组合及其6个亲本的王浆产量和品质性状（台浆量、接受率、王浆产量、酸度）进行了配合力秘杂种优势分析。结果表明：⑴4个性状一般配合力达极显著水平、特殊配合力达显著水平,说明基因加性效应和非加性效应均起作用,但以加性效应为主。⑵乌克兰蜂一般配合力效应高;喀尔巴阡蜂、高加索蜂特殊配合力方差大,均是比较理想的亲本类型;浙农大1号意蜂在台浆量、接受率和王浆产量上一般配合力效应高,是个优良亲本;而卡尼鄂拉蜂只在提高王浆品质时可以利用。⑶4个性状高亲平均优势均为负值,因此利用杂种优质提高王浆产量和品质比较困难,但通过亲本的适当选配,可在维持高产的同时,提高王浆的品质。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.