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Copyright of Cameroon Academy of Sciences Journal is the property of Cameroon Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cameroon Academy of Sciences Journal is the property of Cameroon Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wild rice is high in protein, minerals, and vitamins but low in fat which warrants its development as a functional food. Moreover, rice consumers’ demand for safe and healthy food expanded dynamically over the past few decades. Wild rice contains a high degree of resistance against stress and diseases due to its natural habitat and therefore provides a rich genetic source for rice breeding which is an efficient approach to advance crop genetic improvement efforts. Most cultivated rice was domesticated from a wild rice gene pool; hence, wild rice populations are considered the basis of the original domestication of rice by humans. However, alarming population growth and climate change resulted in wild rice loss of habitat, and its genetic enhancement traits are exploited for the genomic improvement of cultivated rice. The present review provides information on the nutrition and health-improving effects of wild rice species and summarizes the importance of wild rice conservation and its utilization in rice breeding programs.

Capitulum mitella is an important species in the intertidal ecosystem and in the economy in China. This study explored the genetic diversity and population structure of C. mitella using mitochondrial 16S ribosomal subunit (16S rRNA) gene sequences. The researchers sequenced a 527 bp fragment of 16S rRNA from 390 samples collected from six localities along Western Taiwan Strait and identified 45 distinct haplotypes with an average haplotype diversity (h) of 0.451 and an average nucleotide diversity (π) of 0.00124. The pairwise F ST statistics and AMOVA indicated a lack of significant population structure. The results indicated a recent expansion of the population of C. mitella in the study area. This expansion, combined with the species' high dispersal capabilities, limited physical barriers, and the influence of oceanic currents, may be the factors contributing to its current phylogeographic structure. This study provides particularly important information for managing and protecting the resources of C. mitella in Southern China. [ABSTRACT FROM AUTHOR]

D’man est une race ovine importante au Maroc présentant des traits reproductifs exceptionnels. Cependant, sa structure génétique et son état de consanguinité sont peu connus. Cette étude caractérise la diversité de D’man et sa dynamique démographique en utilisant les données génomiques de 30 moutons échantillonnés dans trois régions administratives (Drâa-Tafilalet, Sous-Massa et Guelmim-Ouednoun) pour inférer les paramètres de diversité génétique neutre. De plus, trois approches complémentaires ont été utilisées pour inférer la structure de la population: sNMF pour calculer les coefficients d'admixture individuels, Treemix pour générer un arbre de vraisemblance maximale et des événements de migration, et une analyse en composantes principales. Les résultats ont montré que la race D’man présentait un faible niveau d'hétérozygotie observée, un coefficient de consanguinité élevé et une valeur élevée de diversité nucléotidique par rapport à d'autres races locales. Ces valeurs étaient comparables dans les trois régions et peuvent s'expliquer par l'isolement de cette race et ses systèmes d'élevage typiques. Une certaine structuration géographique a été observée liée aux vallées dont les individus sont originaires. Bien qu'il y ait eu un niveau important de flux génétique, la race s'est révélée bien homogénéisée. L'arbre de vraisemblance maximale a révélé l'existence de deux sous-populations génétiquement distinctes lorsque chaque région administrative était traitée comme un groupe unique, indiquant la présence de deux lignées principales. La race D’man présente donc une diversité génétique remarquable, mais aussi une consanguinité considérable, à prendre en compte pour des programmes d'élevage et de conservation efficaces.

Le cheptel caprin marocain se caractérise par l'existence de différentes populations et races réparties sur diverses zones géographiques ; montagnes et parcours. L'objectif de cette étude était d'analyser les caractères morphométriques et la structure génétique qui différencient la race Drâa des races Atlas, Barcha et Ghazalia. Huit mesures morpho-métriques ont été collectées dans le sud-est du Maroc sur 224 animaux et 16 marqueurs microsatellites ont été génotypés pour 134 échantillons d’ADN. Les résultats ont montré que les caractères morpho-métriques les plus discriminants entre les 4 races étaient la longueur du corps (BL), la hauteur au garrot (HW), le tour de poitrine (HG), la longueur du poil (HL) et le poids corporel (BW). Les caprins Drâa avaient les valeurs les plus élevées pour BL (64,6 cm), HW (61,5 cm), HG (74,4 cm) et BW (27,2 kg). La diversité génétique était importante, uniquement 1,85 % était due aux différences entre les races ; le reste était dû aux différences entre individus. La race Drâa avait les distances génétiques les plus élevées, toutefois, la structure génétique a montré un niveau de mélange élevé entre les races. Il a été conclu que les quatre races caprines étudiées ont une diversité génétique importante mais faiblement structurée, à l'exception de la race Drâa qui a montré un degré plus élevé de différentiation et de structuration. Cette différentiation peut contribuer à définir et à orienter ses programmes d'amélioration génétique.

Rapeseed (Brassica napus L.) crop can be a lever for the development of oilseed sector in Morocco due to its adaptation to local conditions and its major economic and food importance. Genetic diversity and selection of valuable crossing parents are the key to successful breeding and improvement of this crop. In this regard, genetic variation within the existing germplasm must be explored and characterized. Therefore, the present study was carried out to investigate the genetic diversity among 22 varieties from Morocco as well as other origins, using twenty ISSR primers. The selected primers have generated a total of 319 markers. Polymorphic amplified bands varied from 8 to18, with an average of 13 per primer. The diversity index (PIC value) ranged from 0.295 to 0.509, with a mean value of 0.37 per primer, indicating a good genetic diversity level for the primers used. The average similarity coefficient was 0.31, fluctuating between 0.176 and 0.456, and the pairwise comparison of the studied varieties showed a great discriminating power of primers and a large genetic diversity among accessions. A total of eight ISSR primers could be identified as key to rapeseed varietal determination. Hierarchical classification allowed identifying three groups with some phylogeographic structuring. This is the first report of molecular characterization of rapeseed germplasm in Morocco and Africa. The obtained results have important implications for management of this germplasm to conserve the existing genetic diversity and use it properly in breeding programs in Morocco as well as in other Mediterranean and African countries. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ce travail a pour objectif d’étudier la diversité génétique des cultivars locaux de melon collecté au sud tunisien. La caractérisation morphologique de 22 cultivars locaux de melon en se basant sur 32 traits a montré qu’ils se distinguent de la variété commerciale Ananas. En effet, les cultivars locaux du Sud se caractérisent par leur précocité, avec des fruits de plus gros calibre et une faible teneur en sucre. La diversité moléculaire des cultivars de melon, évaluée à l'aide de quatre marqueurs RAPD, a montré un taux de polymorphisme global de 95 %. L’analyse ACP selon les trois premiers axes qui résument 54,7 % de la variabilité totale indique une séparation nette entre la variété Ananas et les cultivars locaux. Les corrélations entre les matrices de distance des données morphologiques et des données moléculaires ont montré que les paramètres longueur des fruits, diamètre des fruits, taille de l’attache pistillaire et l’épaisseur maximal de la chair sont significativement corrélés avec plusieurs marqueurs RAPD. Cette étude a montré une nette distinction entre les cultivars locaux de melon et celui commercial, ce qui a un impact pratique par la sélection des cultivars les plus intéressants ou leur utilisation comme géniteurs pour améliorer les variétés commerciales.

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The red swamp crayfish, Procambarus clarkii (Girard, 1852), is currently an economically important aquaculture animal. Its genetic basis has been scarcely reported, however, partly due to the absence of abundant molecular markers in the genome. In this study, Simple Sequence Repeat (SSR) loci were mined, based on genome survey sequencing via the next generation sequence of the red swamp crayfish. A total of 4897 SSR loci were identified, with the most abundant type being the di-nucleotide repeat motifs (75.2%), followed by tri- (20.4%), tetra- (3.8%), penta- (0.5%), and hexanucleotide (0.2%) repeats. In total, 1546 SSR markers were validated to be amplified, and 721 of these were identified as polymorphic SSR markers. Fifty polymorphic SSR markers were randomly selected for the identification of the genetic diversity of the 14 red swamp crayfish populations in China. The expected and observed heterozygosity and polymorphism information content were 0.39, 0.30, and 0.29, respectively, on average. The results indicated a medium genetic diversity among the 14 investigated populations. These probably cluster into three genetic populations. The current study provides abundant genetic markers and information on the 14 populations, which can be helpful for genetic diversity estimation and molecular breeding of the red swamp crayfish. Résumé: L'écrevisse rouge de Louisiane, Procambarus clarkii (Girard, 1852), est une espèce d'aquaculture importante économiquement. Sa base génétique est peu connue, due en partie à l'absence de marqueurs moléculaires abondants dans son génome. Dans cette étude, l'analyse des microsatellites (SSR) de l'écrevisse rouge a été effectuée, sur la base d'un séquençage du génome par séquençage nouvelle génération (NGS). Un total de 4897 loci SSR ont été identifiés, le type le plus abondant de motifs répétés étant les di-nucléotides (75,2%), suivi par les répétitions à tri- (20,4%), tétra- (3,8%), penta- (0,5%), et hexa-nucléotides (0,2%). Au total, 1546 marqueurs ont été validés pour être amplifiés, et 721 d'entre eux ont été identifiés comme marqueurs SSR polymorphiques. 50 marqueurs SSR polymorphiques ont été sélectionnés au hasard pour l'identification de la diversité génétique des 14 populations d'écrevisse rouge de Louisiane en Chine. L'hétérozygotie attendue et observée et l'indice de polymorphisme ont été, en moyenne, respectivement de 0,39, 0,30, et 0,29. Les résultats montrent une diversité génétique moyenne parmi les 14 populations étudiées, qui se regroupent probablement dans trois populations génétiques. Cette étude fournit des marqueurs génétiques abondants et des informations sur les 14 populations, qui peuvent être utiles pour l'estimation de la diversité génétique et la sélection moléculaire de l'écrevisse rouge de Louisiane. [ABSTRACT FROM AUTHOR]

causes Northern corn leaf blight (NCLB). In this study, 92 isolates of S. turcica were collected from naturally infected corn fields at 57 sites within China to determine physiological race composition and genetic diversity. Based on the reaction of differential hosts, isolates were divided into 14 physiological races (0, 1, 2, 12, 3, 13, 23, N, 1N, 2N, 3N, 13N, 23N, 123N). Races 0 and 1 were dominant, found with frequencies of 34.78% and 28.26%, respectively. This study was the first to identify race 123N in Heilongjiang province, implying possible loss of corn variety resistance to the NCLB pathogen. A total of 64 loci were obtained from eight pairs of primers by sequence-related amplified polymorphism (SRAP), of which 44 were polymorphic, accounting for 68.75% of the loci. Molecular markers showed that 92 isolates could be categorized into four groups with a similarity coefficient of 0.82, indicating abundant genetic diversity. Further analysis of genetic similarity and genetic distance of each geographical population revealed that the populations from Northeast, North, and Northwest China exhibited high similarities to each other, while exhibiting a large genetic distance with those from Southwest China. Analysis of molecular variance indicated that 81.54% of the genetic variation among isolates was derived from individuals within the geographical population (P < 0.001). The cluster analyses suggested that there was no distinct correlation among physiological races, genetic variation and geographic sources. This study provides a basis for understanding trends in S. turcica distribution and control of NCLB in China. [ABSTRACT FROM AUTHOR]

From 1970 to nowadays, breeders have improved oilseed rape (Brassica napus) in many ways: creation of double low varieties (free of erucic acid and with a low content in glucosinolates), increase of the seed yield and quality of seeds and improvement of resistance to diseases. All this work helped oilseed rape to become one of the most produced oilseed crop in the world. However, this intensive breeding on quality has reduced the genetic diversity of winter oilseed rape. In this study, a group of four breeding companies (RAGT, Limagrain, Syngenta, Euralis) called "GIE Colza" has been working with INRAE (National Research Institute for Agriculture, Food and Environment, France) on the FSRSO project "Printiver". This project aimed at enlarging the genetic variability available in winter-type oilseed rape through crossing with spring-type materials to create lines with a winter-type behavior (need of vernalization) and a genetic background that has introgressed spring-type genetic diversity. Two pools have been created and selected for their need of vernalization, date of flowering, yield and other agronomic traits. The Group tested these two pools in multilocal trials. The results show interesting per se value and combining ability. [ABSTRACT FROM AUTHOR]

The nutritional factors and characteristics of sesame (Sesame indicum L.) seeds and extracted oil of six genotypes: G2, G3, G4, G5 and G6 cultivated in Upper Egypt were subjected to comparative evaluation with control (G1), for its genetic diversity, physicochemical properties, fatty acid composition, antioxidant activity and oil oxidative stability (Rancimat test). Estimates of genotypic and phenotypic coefficients of variation revealed high value in seed yield. For heritability estimates, the data showed that four traits out of eight recorded the highest heritability values over of 90%. These traits were oil yield (99.56%), seed yield (98.83%), plant height (96.33%) and seed index (90.03%). Sesame seeds have a high oil content (39.56 to 54.64 g/100g dry weight). The fatty acid profile was varied among the genotypes, in particular oleic acid (37.15 to 46.61%) and linoleic acid (37.49 to 44.33%). Results indicated that G4 has significantly higher in most agricultural traits as well as seed yield, while the G5 was the highest in oil yield and has significantly higher oxidative stability (26.57 h) among the genotypes. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A dataset of approximately 85 apple hammerhead viroid (AHVd) genome sequences was analysed to determine genetic diversity. Sequences analysed included 18 new AHVd variants detected in a 2017/2018 survey, as well as suitable sequences deposited in GenBank. Two phylogenetically distinct clades were observed. A range of indel events was identified with most AHVd sequences ranging in size from 433 to 435 nt. None of these events appear to affect the predicted secondary structure of AHVd, which was well supported by a prevalence of unambiguous covariation events and or substitutions resulting in the conversion of canonical to wobble sequences, or vice versa. All AHVd variants analysed possess the 13 nt that are conserved in most hammerheads of viroids and viroid-like satellite RNA, except at positions 146 and 149. No significant recombination event was identified. [ABSTRACT FROM AUTHOR]

Kenya has, in the last decade, made tremendous progress in the fight against malaria. Nevertheless, continued surveillance of the genetic diversity and population structure of Plasmodium falciparum is required to refine malaria control and to adapt and improve elimination strategies. Twelve neutral microsatellite loci were genotyped in 201 P. falciparum isolates obtained from the Kenyan-Ugandan border (Busia) and from two inland malaria-endemic sites situated in western (Nyando) and coastal (Msambweni) Kenya. Analyses were done to assess the genetic diversity (allelic richness and expected heterozygosity, [He ]), multilocus linkage disequilibrium ( ISA ) and population structure. A similarly high degree of genetic diversity was observed among the three parasite populations surveyed (mean He  = 0.76; P > 0.05). Except in Msambweni, random association of microsatellite loci was observed, indicating high parasite out-breeding. Low to moderate genetic structure (FST  = 0.022-0.076; P < 0.0001) was observed with only 5% variance in allele frequencies observed among the populations. This study shows that the genetic diversity of P. falciparum populations at the Kenyan-Ugandan border is comparable to the parasite populations from inland Kenya. In addition, high genetic diversity, panmixia and weak population structure in this study highlight the fitness of Kenyan P. falciparum populations to successfully withstand malaria control interventions. [ABSTRACT FROM AUTHOR]

The Japanese captive population of Crested Ibis (Nipponia nippon) has rapidly increased, and reintroduction programs were initiated on Sado Island in 2008. The Japanese captive population, however, was founded by only 5 individuals originating from the Chinese captive population. Because efforts were directed toward preserving genetic diversity in the captive population, it was appropriate to consider genetic diversity in the reintroduced population to evaluate its potential to survive in the wild, where environmental changes are more significant than in captivity. The purpose of this study was to determine the number of individuals to release in the future to preserve genetic diversity of the reintroduced population. We simulated the probability that the reintroduced population after 50 years would retain a rare allele existing in the captive population, based on demographic parameters obtained from either the Japanese captive or reintroduced populations, or Chinese wild populations. As a result, the 10–15 individuals currently released in the annual reintroduction would be the number needed to be released each year over 50 years to retain the rare allele with a frequency in the captive population of 0.05 with a .90% probability. Therefore, the current reintroduction program seems reasonable and should be continued. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maire yew ( Taxus chinensis var. mairei (Lemée et Lévl) Cheng et L.K. Fu) is an endangered coniferous species in China. We examined the genetic pattern of Maire yew populations and explored any genetic variation among three groups (Core, Edge, and Disturb) based on hemeroby. Twenty-five populations (533 individuals) were analyzed using nuclear and mitochondrial simple sequence repeat (nSSR and mtSSR, respectively) markers and chloroplast DNA (cpDNA) sequences. nSSR marker analysis indicated a moderate level of genetic diversity ( He = 0.467), a high level of biparental inbreeding within populations ( FIS = 0.314; P < 0.01), and a strong genetic differentiation among populations ( FST = 0.161). Restricted gene flow due to mating characteristics and long-term isolation is the main factor affecting the natural genetic pattern. Our study suggested that human influence had a strong effect on the genetic diversity and differentiation. The results based on nSSR analysis showed that the human-influenced populations (Distub group) had the highest genetic diversity ( He = 0.500, Ar = 3.790) and the lowest genetic differentiation ( FST = 0.062) among populations compared with that of the natural populations (Core group, He = 0.463, Ar = 3.148, FST = 0.221). However, the analysis of cpDNA sequences showed an opposite trend on genetic diversity. The information presented here can supply the basis for genetic guidelines for appropriate conservation programs. [ABSTRACT FROM AUTHOR]

In this study, we employ an integrated demographic-genetic approach with the aim of informing efforts to conserve Ocotea catharinensis Mez., an endangered tree species from the Brazilian Atlantic Rainforest. After establishing two permanent plots (15 and 15.5 ha) within protected areas in Santa Catarina state, Brazil, we evaluated demographic aspects (density, recruitment, mortality, and growth), spatial pattern, genetic diversity, and spatial genetic structure (SGS) in three categories (seedlings, juveniles, and reproductive individuals) over 2 years. Studied populations presented low recruitment of individuals and low rates of increment in diameter and height. Aggregation was the main spatial pattern observed for both populations. High levels of genetic diversity were estimated for both populations, as well as high levels of fixation index, signaling the risk of losing genetic diversity over generations. Significant SGS was found for both populations, reflecting nonrandom distribution of the genotypes. Demographic and genetic surveys also allowed the estimation of minimum viable areas for genetic conservation (>170 ha), deme sizes (around 10 ha), and distances for seed collection (at least 60 m). Effective population size is restricted in studied populations, locally threatening the species perpetuation over generations. Further research can clarify how this condition will change in subsequent years. [ABSTRACT FROM AUTHOR]

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leaf length and width are two of the most important components of rice ( Oryza sativa L.) plant architecture and directly contribute to yield. The genetic effects of leaf length and width are controlled by quantitative trait loci (QTLs). In this study, a double haploid (DH) population derived from a cross of O. sativa subsp. japonica cultivar 'Maybelle' and subsp. indica cultivar 'Baiyeqiu' ('BYQ') was used to determine genetic effects on leaf length and width. Analysis of phenotypic effects indicated that all of the detected traits exhibited continuous, transgressive distributions in the DH population. Correlation analysis revealed a strong association between the two adjacent leaves for the same trait. A total of 25 QTLs within 17 genetic intervals distributed on chromosomes 1, 2, 3, 4, 5, 6, 8, and 12 were detected for rice leaf length and width, with likelihood of odds values that ranged from 2.75 to 10.62. Among these loci, two major QTLs, which were located in the intervals RM3262-RM3452 and RM16432-RM7472, played very important roles in regulating leaf length and width, respectively. Diversity analysis of the two major QTLs revealed that the genetic interval RM16432-RM7472 should be an optimal target for rice breeding programs, and may inspire new research efforts. [ABSTRACT FROM AUTHOR]

Copyright of Revue de Médecine Vétérinaire is the property of Ecole Nationale Veterinaire de Toulouse and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Knowledge of the locations of repeat elements could be very important in the assembly of genome sequences and their assignment to physical chromosomes. Genomic and species relationships among 16 species were investigated using fluorescence in situ hybridization (FISH) with the Am1 and (ACT)6 probes. The Am1 oligonucleotide probe was particularly enriched in the C genomes, whereas the (ACT)6 trinucleotide repeat probe showed a diverse distribution of hybridization patterns in the A, AB, C, AC, and ACD genomes but might not be present in the B and D genomes. The hybridization pattern of Avena sativa was very similar to that of A. insularis, indicating that this species most likely originated from A. insularis as a tetraploid ancestor. Although the two FISH probes failed to identify relationships of more species, this proof-of-concept approach opens the way to the use of FISH probes in assigning other signature elements from genomic sequence to physical chromosomes. [ABSTRACT FROM AUTHOR]

Vibrio alginolyticus, a pathogen among humans and marine animals, is ubiquitous in marine environments. The aims of this study were to analyze the relationships between genetic diversity and origins, and to develop new primers based on the gyrB sequence to identify V. alginolyticus isolated from various sources. To determine the genetic diversity of this bacterium, an arbitrarily primed polymerase chain reaction (AP-PCR) technique was performed on 36 strains of V. alginolyticus isolated from diarrhea patients and from diseased marine animals and environments in southern Thailand. The results showed distinct DNA fingerprints of all strains, indicating that they are genetically heterogeneous. For species-specific identification of V. alginolyticus, primers targeting the gyrB gene of V. alginolyticus were developed. Thirty reference Vibrio spp., 13 non- Vibrio spp., and 160 strains of V. alginolyticus isolated from various sources in southern Thailand were used to evaluate the specificity of these primers. Our results showed that the gyrB primers could specifically identify V. alginolyticus from all sample types. In addition, the detection limit of the PCR was at least 95 pg of DNA template. Therefore, we concluded that the newly designed gyrB primers are rapid, highly sensitive, and specific to identify V. alginolyticus isolated from various sources. [ABSTRACT FROM AUTHOR]

Objective: To elucidate the genetic diversity of Plasmodium falciparum in residual transmission foci of northern India.Methods: Clinically suspected patients with malaria were screened for malaria infection by microscopy. 48 P. falciparum-infected patients were enrolled from tertiary care hospital in Chandigarh, India. Blood samples were collected from enrolled patients, genomic DNA extraction and nested PCR was performed for further species confirmation. Sanger sequencing was carried out using block 2 region of msp1, R2 region of glurp and pfs25-specific primers.Results: Extensive diversity was found in msp1 alleles with predominantly RO33 alleles. Overall allelic prevalence was 55.8% for RO33, 39.5% for MAD20 and 4.7% for K1. Six variants were observed in MAD20, whereas no variant was found in RO33 and K1 alleles. A phylogenetic analysis of RO33 alleles indicated more similarity to South African isolates, whereas MAD20 alleles showed similarity with South-East Asian isolates. In glurp, extensive variation was observed with eleven different alleles based on the AAU repeats. However, pfs25 showed less diversity and was the most stable among the targeted genes.Conclusion: Our findings document the genetic diversity among circulating strains of P. falciparum in an area of India with low malaria transmission and could have implications for control strategies to reach the national goal of malaria elimination. [ABSTRACT FROM AUTHOR]

Subdivided populations can be described by different models of population structure that reflect population organization, dynamics, and connectivity. We used genetic data to investigate population structure in two geographically sympatric, congeneric species of generalist ectoparasites of warm-blooded animals. We characterized the spatial genetic structure of the eastern bat bug ( Cimex adjunctus Barber, 1939), an understudied and fairly abundant species, using microsatellite markers at a spatial scale representing contemporary dispersal of the species. We found seven genetic clusters, global of 0.2, 33% of genetic variation among sites, and nonsignificant isolation-by-distance. We compared these results with the common bed bug ( Cimex lectularius L., 1758), a closely related but conversely well-known species, in the same geographic area. We found stronger genetic structuring in C. lectularius than in C. adjunctus, with 11 genetic clusters, of 0.7, 57% of genetic variation among sites, and significant but weak isolation-by-distance ( R2 = 0.09). These results suggest that while both species can be described as having classic metapopulation structure, C. adjunctus leans more towards a patchy population and C. lectularius leans more towards a nonequilibrium metapopulation. The difference in population structure between these species may be attributable to differences in movement potential and extinction-colonization dynamics. [ABSTRACT FROM AUTHOR]

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The filamentous fungus Fusarium verticillioides is a widely distributed pathogen that causes ear, stalk and root rot of maize. This fungus also produces mycotoxins that accumulate in maize kernels. As chemical control has proven to be insufficient, new and effective disease control measures must be implemented. An improved understanding of the diversity of pathogen populations is thus crucial. Here, a set of 83 F. verticillioides isolates from a major maize-growing region of Mexico was characterized at the pathogenic and genetic diversity levels. A pathogenicity assay on maize seedlings established that all isolates were pathogenic and variable for aggressiveness, with most causing major damage on maize roots (>50% of root rotted). Genetic analysis also revealed high levels of variability, as seen by the high number of haplotypes (76), the population diversity value according to effective number of alleles (6.32), gene diversity (0.80), the polymorphic index content (0.78) and Shannon’s information index (2.06). The analysed F. verticillioides population reproduces asexually, suggesting that the observed genetic and pathogenic diversity is not the result of sexual reproduction and is probably mediated by other evolutionary forces, such as mutation, gene flow, selection and hyphal anastomosis. [ABSTRACT FROM AUTHOR]

Eucalyptus globulus subsp. globulus Labill. (Tasmanian Blue Gum), native to southeast Australia, is a benchmark species for the pulp and paper industry. We genotyped 397 trees from 16 populations of E. globulus representing the native diversity in Australia using 24 microsatellite loci. Eight genetically distinct groups were detected, consistent with genetic groupings detected in previous quantitative and molecular studies. A sample of 29 Portuguese individuals was added to help clarify the origin of the Portuguese landrace. The results suggest a southern and eastern Tasmania origin for the Portuguese landrace. This genetic framework will enable researchers to investigate the provenance of individuals of unknown pedigree and assess the levels of representation of E. globulus natural variation in the Portuguese landrace. [ABSTRACT FROM AUTHOR]

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The American ginseng ( Panax quinquefolius L.) has been used for a wide range of medicinal purposes for more than 300 years, and is at risk in most of its range because of harvesting in natural populations, herbivory, and habitat loss. Its genetic structure is largely unknown in the previously glaciated areas of Eastern Canada, although such information could provide useful information for restoration strategies. We generated and analysed data from a reduced-representation high-throughput sequencing approach with a BAMOVA population model to partition the genetic variation within and among six natural populations of American ginseng in Eastern Canada. We found that an important and significant fraction of the genetic variation was structured among populations ( = 42%; FST = 34%) at the geographical scale of the study (<250 km). No clear evidence of isolation-by-distance was observed. This important genetic structure observed among American ginseng populations from a region that was covered by ice during the last glaciations is similar to what had been found in previous studies on southern populations or throughout the species range. [ABSTRACT FROM AUTHOR]

Castor is an important oilseed crop and although its oil is inedible, it has multiple industrial and pharmaceutical applications. The entire US castor germplasm collection was previously screened for oil content and fatty acid composition, but its genetic diversity and population structure has not been determined. Based on the screening results of oil content, fatty acid composition, and country origins, 574 accessions were selected and genotyped with 22 polymorphic EST-SSR markers. The results from cluster analysis, population structure, and principal component analysis were consistent, and partitioned accessions into four subpopulations. Although there were certain levels of admixtures among groups, these clusters and subpopulations aligned with geographic origins. Both divergent and redundant accessions were identified in this study. The US castor germplasm collection encompasses a moderately high level of genetic diversity (pairwise dissimilarity coefficient = 0.53). The results obtained here will be useful for choosing accessions as parents to make crosses in breeding programs and prioritizing accessions for regeneration to improve germplasm management. A subset of 230 accessions was selected and will be planted in the field for establishing a core collection of the US castor germplasm. Further evaluation of the US castor germplasm collection is also discussed. [ABSTRACT FROM AUTHOR]

The genetic gain and gene diversity of seed crops from a 1.5-generation clonal seed orchard of Pinus koraiensis Siebold & Zucc. were estimated under consideration of parental genetic values and fecundity variation. Fecundity variation among clones was estimated for 5 consecutive years (2010-2014) as the sibling coefficient, which was drawn from clonal contribution to the total production of seed conelet. To monitor gene diversity, status number was estimated by the integration of fecundity variation and group coancestry. Group coancestry was calculated as the average of genetic relatedness (coancestry) among orchard clones. The averages of conelet production were high in 2010 and 2011, moderate in 2013 and 2014, and poor in 2012 with a grand mean of 13.7. Correlation analysis showed that good conelet producers consistently gave good production. Cumulative distribution of clonal conelet production was presented as a function of the total conelet yield, and this distribution indicated deviation from the expected clonal equal production. Group coancesrtry was 0.0096, indicating minimal loss of gene diversity. Status number and genetic gain were higher in good than in poor conelet production years, highlighting the importance of fecundity variation in determining the genetic gain and gene diversity of seed orchard crops. [ABSTRACT FROM AUTHOR]

Studying the genetic diversity and structure of the current forest populations is essential for evaluating the ability to survive future biotic and abiotic changes and planning conservation strategies. Quercus trojana Webb is an eastern Mediterranean tree species with a fragmented distribution range, and its westernmost outposts are located in southern Italy. The demand for timber and cropland over the centuries has severely reduced its occurrence in this part of the range. We assessed the genetic diversity and structure of the extant Italian populations of Q. trojana and derived conservation guidelines. A total of 322 samples were genotyped with six polymorphic nuclear microsatellite markers. A high genetic diversity in all populations, two main gene pools, and a highly divergent single population were observed. Based on the allelic richness and heterozygosity estimation, we identified populations that can be considered as valuable source material for conservation programs and those requiring adequate measures to reestablish gene flow and reduce fragmentation. Finally, a comparison with a set of eastern Mediterranean samples indicated a relationship between the Italian and the Greek gene pools. The need to protect these marginal, disjunct populations was further reinforced. [ABSTRACT FROM AUTHOR]