分子标记在园艺植物上的应用与研究进展

分子标记是继形态学标记、细胞学标记和生化标记之后发展起来的一种新的遗传标记,已广泛应用于园艺植物上.本文综述了分子标记技术在园艺植物种质资源遗传多样性评价、遗传变异检测、遗传图谱构建、分子克隆、分子标记辅助选择育种等领域上的研究进展.文中还就分子标记在园艺植物遗传育种上存在的问题进行了探讨.     

生物技术在橡胶树育种中的应用

综述了生物技术在橡胶树育种中的应用，主要包括组织培养技术、染色体工程技术、分子标记技术、基因工程技术等方面的内容；并展望了其在橡胶树育种中的前景。     

小麦新品种川农16与新材料H461贮藏蛋白及SSR差异分析

应用酸性聚丙烯酰胺凝胶电泳(A-PAGE)、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和简单重复序列(simple sequence repeat,SSR)标记,对穗数型多分蘖小麦品种川农16与大穗型寡分蘖小麦品系H461生化及分子水平上的遗传差异进行了检测.结果表明,川农16与H461间至少有10条醇溶蛋白差异带,其高分子量谷蛋白亚基组成分别为(1,20,5 10)和(2*,7 8,2 12).在小麦21条染色体上的72个SSR位点上共检测到95个等位变异,每一个位点所检测到的等位变异数目为1至2个,平均1.3个;其中,23对SSR引物(31.9%)能够揭示川农16与H461间的差异.     

Confirmation of hybrid origin in Arisaema (Araceae) using molecular markers

A population of hybrids between Arisaema triphyllum subsp. stewardsonii and A. dracontium was investigated using molecular markers to document the hybrid origin. Total genomic DNA was extracted from A. triphyllum, A. dracontium, and the hybrids, and subjected to sequence analysis of various regions of intergenic spacer and genes of chloroplast or intergenic spacer and genes of nuclear ribosome for single nucleotide polymorphisms (SNPs). Clustering was performed using the unweighted pair group method with averages (UPGMA) tested by bootstrap (BS). Hybrid origin could not be easily confirmed in some regions. However, dendrograms constructed with a combined sequence analysis of A. triphyllum 26S ribosomal RNA gene [sequence identification (SI) 467] plus A. tortuosum phytochrome C-like (phyC) gene (SI 468) were very similar to dendrograms constructed from sequences of all regions. This suggests that selecting SI 467 and SI 468 would be practical to identify hybrid origins involving two parental species. Clustering of hybrids together with the female parent in most target regions suggests that, in Arisaema, cpDNA is considered maternally inherited.     

Identification of RAPD markers linked to nut weight and plant stature in cashew

Cashew is an important edible nut crop of tropics. Bulk segregant analysis (BSA) was carried out on DNA bulks constituted from F₂ population and germplasm in order to link or associate molecular markers with economic characters. In all 458 RAPD, 31 ISSR and 21 pairs of SSR primers were used and identified polymorphic markers between parents. Though screening F₂ bulks with these markers identified markers polymorphic between the bulks but none could be validated with the individuals of their bulks. Hence screening with germplasm bulks was carried out and could identify four RAPD markers polymorphic between the bulks for nut weight and plant stature and also between the individuals of their bulks. Of the four, three markers were associated with nut weight amplifying at 775, 475, 275, bp region in primers OPN 14, UBC 184 and UBC 185 respectively. Out of these three, two markers were specific to low nut weight and one marker was specific to high nut weight and their bands were present in greater frequency (50–77.8% and 75%) of individuals constituting the respective bulks. Similarly, the another marker UBC 185₂₇₅ was detected which was specific to low plant stature and was present in 66.7% and 10% individuals constituting short and tall bulks respectively. Markers identified with bulks and with the individuals of bulks were validated further with more individuals of F₂ and germplasm.     

杏杂合位点共显性标记的分离方式及连锁图谱构建

以‘串枝红’ב金太阳’杏的F1代为材料,在分析共显性标记分离方式的基础上利用简单重复序列（SSR）和相关序列扩增多态性（SRAP）标记,构建了两张杏分子连锁图谱。‘串枝红’图谱共14个连锁群,包含37个SSR标记和32个SRAP标记,连锁群总长度为1086.6cM,每连锁群平均长度77.6cM,标记间平均连锁距离为1...     

Clinical evaluation of serum alcohol dehydrogenase activity in horses with acute intestinal obstruction

Objectives – To measure serum alcohol dehydrogenase (ADH) activity in horses with acute intestinal obstruction and to determine the diagnostic and prognostic utility of this analyte. Design – Prospective observational study. Setting – University Veterinary Hospital. Animals – Thirty healthy horses (control group) and 77 horses with acute intestinal obstruction, including 36 horses with nonstrangulating obstruction (23 with left ventral colon impaction and 13 with left dorsal displacement [G1], 22 with small intestinal strangulation [G2], and 19 with colon torsion [G3]). Interventions – Serum ADH activity was assayed spectrophotometerically in all horses. Serum lactate concentration and hepatic enzyme (aspartate aminotransferase, gamma‐glutamyl transferase, glutamate dehydrogenase) activities were measured using an automatic analyzer. Measurements and Main Results – The median [interquartile range] serum ADH activity in healthy horses was 10.5 [8.7 – 11 U/L]. ADH activity was significantly increased (P<0.05) in G1=16.5 [13.8 – 18 U/L], G2=40 [20 – 74.9 U/L], and G3=63.2 [40 – 78 U/L] compared with healthy controls. Aspartate aminotransferase and glutamate dehydrogenase activities were also significantly increased in G3 in comparison with controls. ADH activity was correlated with serum lactate concentration in G1 and G3, respectively (P<0.01, r=0.55 and 0.8). Other liver enzymes did not show any significant correlation with lactate. ADH activity was directly related to the probability of strangulation; odds ratio=1.11. ADH activity >20 U/L had 80.6% specificity and 80.5% sensitivity for discriminating horses with strangulating obstruction. Twelve horses euthanized before surgery were excluded from the outcome analysis. Increasing ADH activity was associated with nonsurvival; odds ratio=1.03. ADH activity <80 U/L had 94.44% specificity and 66.67% sensitivity for survival. Conclusion – Serum ADH activity may be a useful clinical parameter in detecting intestinal strangulation in horses and may provide some prognostic value in horses with acute intestinal obstruction.     

Genetic Analysis of Egyptian Date (<Emphasis Type="Italic">Phoenix dactylifera</Emphasis> L.) Accessions Using AFLP Markers

Forty-seven samples of date palm (Phoenix dactylifera L.) collected from eight locations in Egypt were studied using four sets of amplified fragment length polymorphism (AFLP) markers with near infrared fluorescence labeled primers. These samples belonged to 21 named accessions and 9 of unknown pedigrees. A total of 350 bands were scored and 233 (66.6%) were polymorphic. Twenty-seven Egyptian accessions and ‘Medjool’and ‘Deglet Noor’accessions from California could beclassified into the major cluster. This major cluster may represent a major group of date palm germplasm in North Africa. There were four other clusters, each containing one or two accessions. The variety ‘Halawy’and one accession of unknown provenance were most likely from hybridization between two clusters. Six groups of accessions of which had the same names, revealed similar but not identical AFLP profiles suggesting these accessions might derive from seedlings rather thanthrough clonal offshoot propagation.     

Pattern of genetic diversity of cultivated and non-cultivated mashua, <Emphasis Type="Italic">Tropaeolum tuberosum</Emphasis>, in the Cusco region of Perú

This paper analyzes the genetic diversity of mashua cultivars grown in six communities in the Cusco region of Perú, of non-cultivated forms collected in the same region, and a sample of cultivars from the germplasm collection at the International Potato Center (CIP). From the DNA fingerprinting generated by SRAP markers, it is clear that mashua is a genetically variable crop with a range of similarity ranging from 65 to 99%. The widest range of variation was found for the most isolated community, Sayllafaya. Another important finding was that most of the non-cultivated accessions are likely feral races resulting from escape to cultivation rather than wild relatives. In general the range of variation of the cultivars from the communities and their feral relatives are not represented in the cultivars sampled of the collection maintained at the International Potato Center, Perú.