桃新品种‘冀2102’

‘冀2102’是利用‘晚红蜜’自交培育出的晚熟桃新品种，平均单果质量250g，圆形，色泽鲜艳，风味甜，香气浓，肉质细，多汁，不裂果，可溶性固形物含量12％～13％。白花结实，丰产性强，8月中下旬成熟，适宜在桃适栽区内发展。     

梅花品种分类的花粉形态学研究

对花梅３个系６０个品种的花粉形态进行了光镜和电镜观察，对观测结果进行了主成分分析与聚类分析。结果表明，梅花花粉可以分成６大类；各品种的花粉形态可以较客观地反映梅品种的亲缘演化关系。孢粉学证据基本支持传统的二元三级品种分类系统，但也有异议。垂枝梅类与直枝梅类在花粉形态上不存在显著差异；宫粉型内各品种可能来源不一，且进化程度不一，分化明显，在分类上可以考虑细分；绿萼型品种的形成中可能有李的基因渗入。     

■生长发育过程中和受机械损伤后PPO基因的表达

从■(Prunus salicina Lindl.var.cordataJ.Y.Zhang et al.)成熟叶片均一化全长cDNA文库中新分离得到了1个PPO基因,命名为PsPPO2,基因登录号为JF681036.1。经NCBI-BLAST分析,其核苷酸序列与蔷薇科果树中的河北鸭梨和富士苹果果实的PPO基因具有很高的同源性,分别为81%和80%;与作者先前分离克隆的PsPPO1和PsPPO3基因同源性分别为55%和56%,说明此克隆是PPO基因家族的新成员。通过RT-PCR分析,PsPPO1、PsPPO2和PsPPO这3个基因在■不同生长发育时期和果实受损伤后的表达模式。在叶片发育过程中,PsPPO2表达量都很高;PsPPO1在嫩芽和幼叶中表达;PsPPO3只在嫩芽中表达;在果实发育的不同时期,PsPPO2和PsPPO3在早期表达,随着果实成熟表达量下降,PsPPO1在褐变果中表达量较高。受机械损伤后,PsPPO1受诱导,而PsPPO2和PsPPO3不受诱导。     

通麦野生梅花种质资源调查初报

对通麦野生梅花种质资源进行了调查,为西藏野生梅花的开发利用提供参考依据.西藏通麦梅花分布面积为0.7 km2,集中分布面积0.3 km2.梅花分布密度在垂直带上呈波浪线趋势,下坡梅花天然更新最好,影响梅花生长、更新的主要限制因子是人类及动物的活动所致的生境条件变化;西藏野生梅花幼苗期具有一定的耐阴性,而成苗后表现为喜光.西藏野生梅花在树型上具有明显的种内差异,具体表现为:小乔木状、灌木状及半藤本状等多种类型.     

利用SSR研究不同国家桃育成品种的遗传多样性

利用34对SSR分子标记对来自不同国家的56份桃育成品种进行遗传多样性分析。筛选的13对SSR引物共检测出226个等位基因,其中多态性等位基因为222个。桃群体的平均Nei’s基因多样度为0.224,Shannon遗传多样性表型指数为0.367,说明桃总群体遗传变异较低;基因分化系数为0.081,与AMOVA分析结果8.13%相近,说明2者遗传变异以群体内遗传变异为主;基因流值为5.657,则说明不同国家间桃育成品种交流比较频繁。根据Nei’s基因多样度和Shannon遗传多样性表型指数2指标所得,欧美品种群遗传变异最高,其次为中国,最后为日本。UP-GMA聚类分析结果表明,品种间的遗传距离与系谱关系基本吻合。     

辽西高产山杏间接选种数量性状指标的确定

通过统计理论和SPSS软件对辽西山杏实生群体29个数量性状相关性、变异性和分布特征的研究表明:与经济性状核、仁相关的数量性状有嫩枝长、叶柄长、叶柄宽、叶形指数、果体、果皮厚、果重、核体、核皮厚;变异系数以雌蕊发育程度最大,高达86.5%,其次变异系数>20%的依次为果重、出核率、嫩枝长、核重、果皮厚、仁重、出仁率、仁形指数;所测性状均呈正态分布。将相关性、变异性相结合,确定雌蕊发育程度、嫩枝长度、叶形指数、果体、果重作为高产山杏间接选种的主要数量性状指标。     

Mapping major genes and quantitative trait loci controlling agronomic traits in almond

Six tree traits (self-compatibility, blooming date, blooming density, productivity, leafing date and ripening time) and five pomological traits (kernel taste, in-shell weight, shell hardness, kernel weight and double kernel) were studied in an F₁ almond progeny of 167 seedlings from the cross between the French cultivar 'R1000' and the Spanish cultivar 'Desmayo Largueta'. In addition, a set of 135 codominant microsatellites or simple-sequence repeat (SSR) markers developed from peach, cherry and almond were used for the molecular characterization of the progeny. A genetic linkage map was constructed with 56 of these SSRs. Cosegregation analysis allowed the identification of the map positions of two major genes to be confirmed for kernel taste ( Sk ) in linkage group five (G5) and for self-incompatibility ( S ) in G6. QTLs mapped include two for leafing date ( Lf-Q1 and Lf-Q2 ) in G1 and G4, one for shell hardness ( D-Q ) in G2, one each for double kernel ( Dk-Q ) and productivity ( P-Q ) in G4, one for blooming date ( Lb-Q ) in G4, two for kernel weight ( Kw-Q1 and Kw-Q2 ) in G1 and G4, and two for in-shell weight ( Shw-Q1 and Shw-Q2 ) in G1 and G2. Four SSR loci (BPPCT011, UDP96-013, UDP96-003 and PceGA025) were linked to the important agronomic traits of leafing date, shell hardness, blooming date and kernel taste. Finally, the development of efficient marker-assisted selection strategies applied to almond and other Prunus breeding programmes was also discussed.     

果梅NAC基因家族的鉴定及组织表达分析

为挖掘果梅中NAC基因成员,探讨其组织表达特异性,本研究采用生物信息学方法鉴定了果梅NAC基因家族,并对其理化性质、染色体分布、亚细胞定位、保守基序、蛋白结构和亚族分类进行预测分析。结果表明,果梅NAC基因家族包含106个NAC基因成员,根据系统发育特征将其分为12个亚族。PmNAC基因在果梅的8条染色体上呈现不均匀分布,多编码酸性氨基酸;大部分NAC蛋白为亲水蛋白,其二级结构多以无规则卷曲为主要构成元件,且三级结构相似;亚细胞定位预测显示,果梅NAC蛋白为典型的核蛋白。选取12个NAC基因家族成员,利用实时荧光定量PCR技术进行组织表达分析,结果表明,12个果梅NAC基因在不同组织中均有表达,但表达差异明显。其中3个基因(PmNAC54、PmNAC32、PmNAC68)在果皮中表达最高,4个基因(PmNAC60、PmNAC95、PmNAC51、PmNAC2)在果肉中表达最高,3个基因(PmNAC31、PmNAC62、PmNAC48)在嫩茎中表达最高,其余2个基因(PmNAC61和PmNAC71)分别在果胚和花芽中具有最高的表达,表达特征的差异表明它们可能具有不同的生物学功能。本研究结果为果梅NAC蛋白的进一步功能分析奠定了一定的理论基础。     

桃杂交后代主要经济性状遗传变异分析

对桃品种（系）１２个杂交组合１３６１个单系的后代主要经济性状的遗传变异情况进行了分析，包括Ｆ＿１开花期、果实成熟期、果实大小、颜色和风味、果形、果肉硬度、果肉颜色、丰产性、核粘离性、树体性状和综合品质等，为进一步合理配置亲本提供参考依据。     

Characterization and PCR-based detection of benzimidazole-resistant isolates of Monilinia laxa in California

Monilinia laxa is a pathogen of brown rot of stone fruit and almond in California, causing blossom blights and fruit rots. In this study, low-level resistance to the benzimidazole fungicides benomyl and thiophanate-methyl was detected in field isolates of M laxa collected from stone fruits and almonds in California. Low-resistant (LR) isolates grew in potato dextrose agar (PDA) plates amended with benomyl and thiophanate-methyl at 1 and 5 microg ml(-1), respectively, but not in plates amended with benomyl at 5 microg ml(-1) or thiophanate-methyl at 50 microg ml(-1). The benzimidazole LR isolates were characterized by temperature sensitivity and the DNA sequence of the beta-tubulin gene. The LR isolates showed high-temperature sensitivity, being sensitive to 1 microg ml(-1) of benomyl at 28 degrees C but resistant at 8-24 degrees C. Analysis of the DNA sequence of the beta-tubulin gene showed that the LR isolates had a point mutation at the amino-acid position 240, causing substitution of leucine by phenylalanine. Based on the point mutation, a pair of allele-specific PCR primers was developed for rapid detection of LR isolates of M laxa. In addition, a pair of PCR primers specific to M laxa was developed on the basis of the differences in the DNA sequence of the intron 6 of beta-tubulin gene from M laxa, M fructicola and other fungal species. The primer pair amplified the expected 376-bp DNA fragment from all M laxa isolates tested, but not from 14 other fungal species isolated from stone fruit and almond crops. The restriction endonuclease BsmA I recognized the sequence GTCTCC in the PCR products from sensitive (S) isolates only, but not the GTTTCC sequence in the PCR products from LR isolates. The endonuclease digested the 376-bp PCR products from S isolates to produce two bands (111 and 265 bp) on agarose gels. Thus, both allele-specific PCR and the PCR-restriction fragment length polymorphism (PCR-RFLP) methods could be useful for rapidly detecting benzimidazole-resistant isolates of M laxa from stone fruit and almond crops in California.