Genetic diversity of Lilium tsingtauense in China and Korea revealed by ISSR markers and morphological characters

To study the genetic diversity and population structure of Lilium tsingtauense Gilg (Qingdao Lily), we collected 648 samples from 12 sites in China and Korea, and analyzed their Inter-Simple Sequence Repeat (ISSR) molecular markers and morphological characters. ISSR data revealed a relatively high genetic diversity at the species level, with 72.31% polymorphic loci, effective numbers of alleles of 1.437, average expected heterozygosity of 0.231 and Shannon’s information index of 0.369. Considerable genetic differentiation among the natural populations (G_ST = 0.144) and the gene flow (N_m = 1.487) were detected. AMOVA analysis and UPGMA-dendrogram suggested a hierarchical regional structure among populations, and spatial autocorrelation analysis showed a micro-scaled spatial structure. Furthermore, there was a high correlation between morphological characters and genetic parameters obtained from ISSR parameters. There was only a low genetic differentiation among the different morphological types of L. tsingtauence in China. Based on these findings, we recommend in situ and ex situ conservation strategies for the preservation of L. tsingtauense.     

Identification of stock components using morphological markers

This study investigated the development of a quantitative method for distinguishing stock components of Icelandic cod Gadus morhua based on visual examination of morphology. The stock is known to be structured into genetically distinct geographic components (north and south of Iceland) and behavioural types that spawn sympatrically. Differences in morphology were tested between locations, genotypes (a proxy for behaviour) and sexes. Results show morphological markers on the head, fins and body of G. morhua that are correlated with the sex, genotype of the fish at the pantophysin (pan‐I) locus and the location at which the fish were caught. Females were found to have relatively deep bodies, and the pan‐I^BB genotype (associated with deep‐water feeding behaviour) have greater gaps between their fins. Overall, morphology is more useful for distinguishing sympatric genotypes but less powerful at identifying genetically distinct geographic sub‐populations, perhaps because counter‐gradient evolution reduces phenotypic differences even with an underlying genetic cause.     

Identification of RAPD markers linked to the ps gene and their usefulness for purity determination of breeding lines and F1 tomato hybrids

The functional male sterility controlled by ps gene proved to be a useful tool in hybrid tomato varieties breeding in Poland. The climat conditions such as excessive temperature and high humidity have a bad effect on the expression and stability of functional male sterility. Using the RAPD methods we have identified two RAPD markers linked to the ps gene. The markers OPW 13₁₂₃₀ and OPAX 10₇₈₀ were generated by 5′CACAGCGACA 3′ and 5′CCAGGCTGAC 3′ decamers respectively in F₂ population of combination 24/29 × G-1.     

Multivariate analysis of tooth crown morphology in Japanese-American F1 hybrids

Mesiodistal crown diameters of I1 through M1 and six non-metric crown traits in permanent dentition of Japanese-American F₁ hybrids were compared with those of the parental populations. The hybrids were born of Japanese females and American males, both Caucasians and American Blacks, after World War II and brought up at Elizabeth Saunders Home in Kanagawa Prefecture, Japan. The comparisons were undertaken by means of multivariate analysis methods such as principal component analysis, distance and similarity coefficients and multidimensional scaling. The F₁ hybrids generally occupy an intermediate position of the two parental populations, and this is particularly evident in size component of the crown measurements and in distance analysis of frequencies of the non-metric crown traits. The shape component of the crown measurements, however, not necessarily follows such a rule and suggests a more complicated gene control than in the case of the size component. Also, each measurement and frequency of non-metric trait of tooth crowns in F₁ hybrids is not uniformly at the middle position between their parental populations but this is true when they are analyzed as multivariables.     

Evaluation of genetic diversity within asparagus germplasm based on morphological traits and ISSR markers

Asparagus officinalis L. is a dioecious perennial plant globally known for its fine flavor and high nutritional value. An evaluation of genetic diversity in 46 asparagus accessions was carried out based on morphological and inter-simple sequence repeat (ISSR) markers. The result show that the coefficient of variation for 20 morphological characteristics is between 12.45 and 62.22%. Factor analysis revealed that nine factors explained 83.37% of the total variance. At Euclidean distance of 135.7, 46 accessions were divided into two clusters. Genetic similarity coefficient (GSC) based on ISSR data ranged from 0.60 to 0.97, suggesting a relatively abundant genetic base. Furthermore, the 46 asparagus accessions could also be grouped into three major clusters at a GSC of 0.74. And there is no significant relation between the two marker systems using the Mantel test. Clustering based on morphological traits compared with that based on ISSR data was not consistent, however, some common groupings were observed between two dendrograms. Therefore the results elucidated asparagus germplasm genetic background and determined hybrid parents, which will facilitate optimal application of asparagus germplasm resources and provide additional data for genetic improvement.

     

Genetic diversity revealed by morphological traits and ISSR markers in 48 Okras (Abelmoschus escullentus L.)

Physiology and Molecular Biology of Plants - Okra is a widely distributed crop in the tropics, subtropics, and warmer areas of the temperate zones. Its major potential uses as a vegetable, oil and...     

Hematologic and enzymatic analysis of Ctenopharyngodon idella x Hypophthalmichthys nobilis F1 hybrids

1. Erythrocyte counts, hemoglobin concentrations and hematocrit values were determined for diploid and triploid Ctenopharyngodon idella X Hypophthalmichthys nobilis hybrids and the parental species. 2. Comparisons of diploid and triploid hybrids with the parental species revealed low erythrocyte counts for triploids, high mean corpuscular hemoglobin values for triploids, elevated hematocrits for diploids and triploids and similar hemoglobin concentrations for all fish. 3. Alkaline phosphatase, aldolase, and lactate dehydrogenase specific activities were determined spectrophotometrically. Levels of specific activity of these enzymes in the hybrids were consistently elevated above that of the parental species. These higher levels of enzyme activities in hybrids were probably the result of a breakdown in gene regulation.     

Comparative analysis of ISSR marker polymorphism in populations of yak (Bos mutus) and in F1 hybrids between yak and cattle in the Sayan-Altai region

The genetic variability in seven yak populations from the Sayan-Altai region and in F₁ hybrids between yak and cattle (khainags) was investigated with the help of a technique that involves the use of inter simple sequence repeat (ISSR) markers generated with PCR primers (AG)⁹C and (GA)⁹C. Samples for the analysis were collected in Mongolia, Tuva, and Altai from 2008 through 2012. The examined yak populations differed in in the presence/absence of ISSR fragments, as well as in their frequency. In total, 46 ISSR fragments were identified using two marker systems; the proportion of polymorphic loci constituted 76% and 90% for the AG-ISSR and GA-ISSR markers, respectively. For the total sample of yaks, total genetic diversity (H _t), within-population diversity (H _s), and interpopulation diversity (G _st) constituted 0.081, 0.044, and 0.459 for the AG-ISSR and 0.137, 0.057, and 0.582 for the GA-ISSR markers, respectively. Based on ISSR finger-printing, species- and breed-specific DNA patterns were described for the three groups of animals (yaks, cattle, khainags). For the domestic yak, the species-specific profile was represented by eight ISSR fragments. Genetic relationships between the yak populations, cattle breeds, and khainags were examined with the help of four different approaches used in the analysis of population structure: estimation of phylogenetic similarity, multidimensional scaling, principal component analysis, and cluster analysis. Clear evidence on the differentiation of the populations examined at the interspecific, as well as at intraspecific, level were obtained. Similar (relative), as well as remote (isolated), yak populations were identified. Khainags occupy an intermediate position between yak and cattle. However, the data on the ISSR-PCR marker polymorphism (genome polymorphism, population structure) indicate that part of the analyzed khainag genome was more similar to the yak genome than to the cattle genome.     

Characterization of somatic hybrids of potato by use of RAPD markers and isozyme analysis

Electrofusion of mesophyll protoplasts from two male sterile dihaploid Solanum tuberosum genotypes. DHAK-11 and DHAK-33, was performed. Selection of putative fusion products was based on vigorous callus growth. Regeneration of rooted putative hybrid plants was scored 14 weeks after fusion. Characterization of hybrids was performed by use of morphological assessment, random amplified polymorphic DNA (RAPD), and cytological and isozyme analysis. The rate of regenerated hybrids from callus was ca 6%. Of the putative hybrids, 45% were confirmed as true hybrids. Morphological assessment of the putative hybrids revealed that tetraploid and neartetraploid hybrids were vigorous plants with intermediate characteristics between the two parental phenotypes in respect to internode length, leaf size and shape, and purple pigmentation on the abaxial side of the leaves. Near-hexaploid hybrids were slender plants with small leaves and short petioles. Selected RAPD primers showed unique marker bands for the two parental genotypes. Hybrid plants revealed the unique marker bands from both parents. A total of 53 randomly chosen decamer primers were tested and 26 primers (49%) detected polymorphism between the two dihaploid parentals. Two primers revealed that one parental marker band was missing in two aneuploid hybrids. However, of 51 putative hybrids, a double test with two independently chosen primers showed unequivocally the hybrid character of 23 plants. The ploidy level of the hybrids was analysed by chromosome numbers in root tip cells and by number of guard cell chloroplasts. A strong correlation between the chromosome number and the number of chloroplasts was obtained. The hybrid nature of all RAPD-verified hybrids was confirmed by isozyme analysis with malate dehydrogenase.     

Estimation of diversity by morphological markers

A genetic statistical method for estimation of intraspecific diversity of cultivated plants with respect to morphological genes is proposed. The method may be used for estimation of probability distributions of morphological (marker) mutations with respect to the frequencies of their expression and for prediction of experimental parameter such as the total number of markers, the scale (duration) of the experiment that is necessary for detection of a given proportion of the total marker diversity of the species, etc. The method was tested on tomato Lycopersicon esculentum Mill. using data from the SolGenes Internet databank.     

21种野生百合亲缘关系的ISSR分析

该研究选用7条ISSR标记引物对百合属21种野生百合的亲缘关系进行分析,使用POPGEN1.32和MEGA5.1数据处理软件分析数据。结果表明：7条引物扩增出149条条带,其中136条为多态性条带,多态性条带比率为91.06％,平均有效等位点数为1.7624,平均Nei’ s基因多样度为0.4214,平均Shanon信息指数0.6085。遗传距离变化范围为0.3075~0.8873,紫脊百合和尖被百合的遗传距离最大,均值为0.8873,表明21份材料中二者亲缘关系最远;紫脊百合和宜昌百合遗传距离最小,均值为0.3075,表明二者亲缘关系最近。聚类结果与形态学分类大致吻合,21个供试材料可被分成5个类群,大理百合、宝兴百合、卷丹百合、紫斑百合、乳头百合、川百合、兰州百合、山丹百合、绿花百合和毛百合为第Ⅰ类群;紫脊百合、宜昌百合、岷江百合、通江百合和淡黄花百合为第Ⅱ类群;野百合和百合为第Ⅲ类群;青岛百合为第Ⅳ类群;第Ⅴ类群包括玫红百合、有斑百合和尖被百合。毛百合与卷瓣组百合亲缘关系较近,钟花组百合与卷瓣组百合存在基因交流,说明不能仅仅依靠形态学对野生百合进行分类。聚类分析结果中野百合与百合单独聚为一类,这说明是否具叶柄对野生百合的分类是一个重要的形态学特性。 ISSR分子标记适合用于百合属植物的亲缘关系分析。     

Proteomic analysis of F1 hybrids and intermediate variants in a Littorina saxatilis hybrid zone

Proteomic analysis was carried out on the Crab (upper-shore) and Wave (lower-shore) ecotypes of Littorina saxatilis from a hybrid zone at Silleiro Cape, Spain. Proteome profiles of individual snails were obtained. Protein expression in F₁ hybrid snails bred in the laboratory and snails with intermediate shell phenotypes collected from the mid-shore were compared with Crab and Wave ecotypes using analytical approaches used to study dominance. Multivariate analysis over many protein spots showed that the F₁ snails are distinct from both ecotypes but closer to the Wave ecotype. The intermediate snails are highly variable, some closer to the Crab and others to the Wave ecotype. Considered on a protein by protein basis, some proteins are significantly closer in expression to the Crab and others to the Wave ecotype for both F₁ and intermediate snails. Furthermore, a significant majority of proteins were closer in expression to the Wave ecotype for the F₁, consistent with the multivariate analysis. No such significant majority toward either the Crab or Wave ecotype was observed for the intermediate snails. The closer similarity of F₁ and Wave ecotype expression patterns could be the result of similar selective pressures in the similar mid-shore and low-shore environments. For a significantly larger number of proteins, intermediate snails were closer in expression to the ecotype having the lower expression, for both Crab and Wave ecotypes. This is somewhat unexpected as lower expression might be expected to be an indication of impairment of function and lower fitness. Proteomic analysis could be important for the identification of candidate proteins useful for gaining improved understanding of adaptation and barriers to gene flow in hybrid zones.     

Genetic variation of the genus Kengyilia by ISSR markers

We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR (inter-simple sequence repeat) markers.The results showed that genetic variation was relatively higher among the accessions.A total of 593 bands were amplified by 12 ISSR primers,of which 535 bands (90.2%) were polymorphic.Eleven to 80 polymorphie bands were amplified from each prime,with an average of 44.6 bands.The interspecies GS (genetic similarity)value ranged from 0.430 to 0.866,and the average was 0.620.Cluster analysis showed that all accessions could be classified into 4 groups by ISSR markers.The different accessions in a species were clustered together,but they had genetic variation in molecular levels.There was obvious interspecies genetic variation.Species with similar morphological characteristics and from the same areas or neighboring geographical regions were clustered together and had close relationships.ISSR markers are useful in analyzing interspecies variation in Kengyilia.     

Hybridization between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae): development and morphological characterization of F1 hybrids

Reciprocal hybridizations between Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) were studied. The cross between females of H. armigera and males of H. assulta yielded only fertile males and sterile individuals lacking an aedeagus, valva or ostium bursae. A total of 492 larvae of the F1 generation were obtained and 374 of these completed larval development and pupated. Only 203 pupae were morphologically normal males, the remaining 171 pupae were malformed. Larvae and pupae that gave rise to morphologically abnormal adults exhibited longer development times. Sterility was not only associated with malformed external sex organs, but also a range of abnormalities of the internal reproductive system: (i) loss of internal reproductive organs, (ii) with one to three copies of an undeveloped bursa copulatrix; or (iii) with one or two undeveloped testes. Normal male hybrid adults showed higher flight activity in comparison with males of both species. In contrast, the cross between females of H. assulta and males of H. armigera yielded morphologically normal offspring (80 males and 83 females). The interaction of the Z-chromosome from H. assulta with autosomes from H. armigera might result in morphological abnormalities found in hybrids and backcrosses, and maternal-zygotic incompatibilities might contribute to sex bias attributed to hybrid inviability.     

Identification and association of ISSR markers for thermal stress in polyvoltine silkworm Bombyx mori

Evaluation of genetic resources is an essential prerequisite for their effective utilization. In India, the tropical climate prevails in most of the sericultural belts, where temperature goes beyond the ambient during summer, adversely affecting the silkworm rearing. Although polyvoltine silkworms are poor in silk content, they are mostly tolerant to tropical conditions and diseases. With an aim to identify potential silkworm races/breeds specific to thermo-tolerance for their effective utilization in breeding programme, 15 selected polyvoltine silkworm races were studied for their thermo-tolerance behaviour. Their genomic DNA samples were analyzed for ISSR-PCR using 15 selected primers. The UPGMA analysis based on Nei and Li algorithm has clustered the 15 silkworm races into five groups and one isolate. ALSCAL-multidimensional scaling has not only supported the information generated by the dendrogram, but it has made the genetic distance among races more clear and substantiating their status in terms of thermal stress where pupation rate was taken as indicator. Further, discriminant function analysis (DFA) was done with three groups of silkworms classified for thermal stress viz. susceptible, moderately tolerant and tolerant. The canonical correlation value was estimated to be 0.987 (Wilk's lambda = 0.004; chi2 = 36.044, p < 0.05). DFA clearly discriminated the above three groups. Beta statistics with t value and its significance for the markers identified through stepwise multiple regression analysis (MRA) revealed a total of five bands (807(1300), 808(3000), 808(4000), 834(4000), and 834(3000)) showing correlation with pupation rate after thermal treatment. Out of them, marker 8083000 showed maximum and highly significant correlation (r = 0.757, p < 0.001, t = 4.182) with pupation rate among the silkworm races. The identified putative markers are being used to develop DNA marker to be used in evolving thermo-tolerant silkworm breeds using marker assisted selection programme.     

不同龙眼资源遗传多样性的SCoT和ISSR 比较分析

应用SCoT和ISSR标记对36份龙眼资源和1份近缘种龙荔的遗传多样性进行分析。结果表明:12对SCoT引物共扩增出127条带,平均每条引物扩增10.58条带;15条ISSR引物共扩增出117个条带,平均扩增7.8条带。UPGMA聚类结果表明:SCoT标记和ISSR标记分别在相似系数0.672和0.685水平上,均可将37份材料分成6大类群,SCoT和ISSR标记均适用于龙眼材料的遗传多样性分析,如果将两种标记的数据进行综合分析,可以缩小单一标记的误差。研究结果为龙眼种质资源的保存和利用提供了重要的依据。     

野生罗汉果遗传多样性的ISSR分析

应用ISSR分子标记方法对采自广西和广东的7个罗汉果（Siraitia grosvenorii）野生居群共130个个体进行了遗传多样性分析。15个ISSR引物共扩增到了111个位点,其中91个是多态性位点,占82.0%。Nei′s基因多样性指数(H_e)为 0.248,Shannon 信息多样性指数（I） 为0.354。罗汉果不同居群的遗传多样性水平差异较大,居群多态位点百分率在 28.2%－55.6%之间,Nei′s基因多样性指数为0.080－0.209,Shannon 信息多样性指数为0.123－0.310。永福居群（YF）和金秀居群（JX）的遗传多样性水平较高,其周边居群的遗传多样性水平逐渐降低,居群间产生了较大的遗传分化（G_st = 0.569）。居群间的遗传距离与地理距离相关性不明显（r =0.369,P = 0.115）。UPGMA聚类图中,7个居群的个体按居群各自聚在一起。     

香菇单孢杂交子代群体灰色关联度和ISSR分析

以香菇Lentinula edodes栽培菌株秋6和K95-1为亲本,通过单孢菌株配对杂交获得21个杂交子,观察杂交子及亲本菌丝体生长情况,进行栽培出菇试验。采用灰色关联度分析法,对9个正常出菇的杂交子从8个性状方面进行综合评价,结果表明,杂交子QK-8和QK-15关联度仅次于亲本秋6,农艺性状和子实体性状表现最好。采用ISSR技术对21个杂交子及亲本进行DNA多态性聚类分析,单孢杂交后代遗传分化十分明显,归于同一类群的杂交子在菌丝生长、子实体形态和农艺性状等方面常表现相似,ISSR分析能为优良杂交子初步筛选提供重要参考。     

Inheritance of RAPDs in F1 hybrids of corn

Summary Random amplified polymorphic DNA (RAPD) markers were analyzed in materials from a partial diallel, including 16 corn F₁ hybrids (with five reciprocals) and their five parental inbreds. Using 21 primers, we scored a total of 140 different fragments for their presence/absence and intensity variation, where appropriate. When all 21 genotypes were taken into consideration, 20.7% of these fragments were nonpolymorphic, 37.1% were unambiguously polymorphic, and 42.1% were quantitatively polymorphic. Unambiguous polymorphisms were distinguished by the simple presence or absence of a specific fragment in the inbred genotypes, whereas quantitative polymorphisms exhibited a variation in the intensity of a fragment. Of the F₁ patterns, 95.2% of the unambiguously polymorphic situations could be interpreted genetically by assuming complete dominance of the presence of the parental fragment, while 3.2% of the F₁ patterns exhibited a fragment intensity that was intermediate between the two parental patterns (partial dominance). For quantitative polymorphisms, values of 88.1% for complete dominance and 5.0% for partial dominance were obtained. The results suggest that specific types of errors can be detected in RAPD analysis, that uniparental inheritance is not common, and that RAPD analysis might be more prudently used for some applications than for others.     

Resistance of tomato F1 hybrids to grey mold

A two-year estimation of Botrytis cinerea stem damage of 299 experimental F₁hybrids grown in 2 rotations: winter-autumn and summer-autumn was carried out. The estimation was made in a period of mass fruitage. As a result it was shown, that the hybrids with determinate type of growth (sp) are damaged more strongly than indeterminate ones (sp +). An average disease severity in the first group was 2.8 against 2.3 in the second one using a scale 0–4. Number of strongly injured (2.5–4) plants in each group were 44.1 % and 30.7 % and number of moderate resistant (0–1.5 numbers) plants were 10 % and 8.5 % accordingly. The analysis of resistance of F₁ hybrids determined significant influence of parental lines on a degree of a damage of plant stems by B. cinerea.