Pod Morphology, Primary and Secondary Metabolite Profiles in Non-grafted and Grafted Carob Germplasm Are Configured by Agro-Environmental Zone, Genotype, and Growing Season

Carob is a predominantly rainfed tree crop of high nutritive value and a long history of adaptation to the edaphoclimatic stress conditions of the Mediterranean. However, declining attention to the carob tree in recent decades has aggravated genetic erosion. The extant in situ germplasm varies both in terms of pod morphology and composition, reflecting the genetic and physiological divide chiefly among grafted and non-grafted material, and possibly the impact of variable agro-environments. Accordingly, the present study aimed to establish a systematic categorization of the genetic and phenotypic diversity encountered across carob germplasm identified in situ throughout Cyprus, a historical center of production and genetic diversity for the species. Linking pod morphology, primary and secondary metabolite profiles with genotyped source material originating in different agro-environments and crop seasons would provide a framework for interpreting (a) the interaction of these factors in configuring carob pod physicochemical constitution, and (b) the relative stability of phenotypic traits against environmental and seasonal variation. Microsatellite analysis discriminated 36 genotypes out of the 124 trees located in nine traditional agro-environmental zones and revealed low genetic diversity within the grafted germplasm. Two landraces were identified: “Tillyria,” which is widespread and predominant, and “Kountourka,” which is mainly localized to the northeastern peninsula of Karpasia. Morphological traits, such as seeds-to-pod weight ratio, pod width and thickness were principally under genetic control. Contrarily, compositional traits, particularly total phenolic content—including condensed tannins, in vitro antioxidant capacity and to a lesser extent gallic acid, organic acids and minerals were under agro-environmental control. Agro-environmental zone also modulated principally fructose and glucose; sucrose was modulated equally by genotype and agro-environment, while total sugars were under genetic control. Statistically significant differences between seasons were detected for all traits except for the seeds-to-pod weight ratio, pod length and width. Hierarchical cluster analysis corroborates that Cyprus may be divided into two major agro-environmental zones modulating the compositional properties of the carob pulp. The present study provides a comprehensive insight into the extant carob genetic resources of Cyprus and advances our understanding of how genetic, agro-environmental and seasonal factors interact in shaping carob pod morphology and composition.

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Strategies for conservation of germplasm in endemic redwoods in the face of climate change: a review

Plant Genetic Resources ◽

10.1017/s1479262111000153 ◽

2011 ◽

Vol 9 (3) ◽

pp. 411-422 ◽

Cited By ~ 5

Author(s):

M. R. Ahuja

Keyword(s):

Climate Change ◽

Genetic Diversity ◽

Conservation Strategy ◽

Ex Situ ◽

Conservation Strategies ◽

Phenotypic Traits ◽

Coast Redwood ◽

Giant Sequoia ◽

The Face

This study reviews the various conservation strategies applied to the four redwood species, namely coast redwood (Sequoia sempervirens), Sierra redwood or giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides) and South American redwood or alerce (Fitzroya cupressoides), which are endemic in the USA, China and South America, respectively. All four redwood genera belong to the family Cupressaceae; they are monospecific, share a number of common phenotypic traits, including red wood, and are threatened in their native ranges due to human activity and a changing climate. Therefore, the management objective should be to conserve representative populations of the native species with as much genetic diversity as possible for their future survival. Those representative populations exhibiting relatively high levels of genetic diversity should be selected for germplasm preservation and monitored during the conservation phase by using molecular markers. In situ and ex situ strategies for the preservation of germplasm of the redwoods are discussed in this study. A holistic in situ gene conservation strategy calls for the regeneration of a large number of diverse redwood genotypes that exhibit adequate levels of neutral and adaptive genetic variability, by generative and vegetative methods for their preservation and maintenance in their endemic locations. At the same time, it would be desirable to conserve the redwoods in new ex situ reserves, away from their endemic locations with similar as well as different environmental conditions for testing their growth and survival capacities. In addition, other ex situ strategies involving biotechnological approaches for preservation of seeds, tissues, pollen and DNA in genebanks should also be fully exploited in the face of global climate change.

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Indirect estimates reveal the potential of transgene flow in the crop–wild–weed Sorghum bicolor complex in its centre of origin, Ethiopia

Plant Genetic Resources ◽

10.1017/s1479262116000204 ◽

2016 ◽

Vol 15 (6) ◽

pp. 496-505

Author(s):

Asfaw Adugna ◽

Endashaw Bekele

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Phenotypic Traits ◽

Wild Populations ◽

Centre Of Origin ◽

Transgene Flow ◽

Potential Risks ◽

Cultivated Populations ◽

Simple Sequence

AbstractA study was carried out between 2008 and 2011 to investigate the potential risks of gene flow and its consequences in the crop–wild–weed S. bicolor complex in Ethiopia to aid efforts to conserve genetic diversity. Morphological measurements and genomic DNA samples were taken in situ from 30 wild and eight cultivated populations representing a total of 760 samples from five regions. Genetic diversity, gene flow, population structure and outcrossing rates of wild populations were computed using phenotypic measurements and/or polymorphic simple sequence repeat (SSR) markers. Moreover, morphological analyses of fitness of crop–wild hybrids were studied. High diversity was observed among the wild/weedy sorghum populations for phenotypic traits and SSRs. SSR diversity was high in both wild and cultivated populations, but the magnitude was greater in the former. Gene flow between the wild and the cultivated sorghum was observed to be higher than that within either pool. Wild sorghums exhibited variation in the multilocus outcrossing rate (range = 0.31–0.65) and fitness was not compromised in most wild × crop hybrids. The study indicated that crop-to-wild gene flow is possible in Ethiopia. Thus, genes from transgenic sorghum are expected to enter into the wild and non-transgenic cultivated populations and may spread and persist, if transgenic sorghum is deployed in Ethiopia and in other countries of Africa, which may pose risk of introduction of unwanted effects, which in turn may lead to loss of genetic diversity.

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Impact of fertility variation on genetic diversity and phenotypic traits in second generation seed production areas and clonal seed orchards of Eucalyptus camaldulensis

Silvae Genetica ◽

10.2478/sg-2019-0006 ◽

2019 ◽

Vol 68 (1) ◽

pp. 29-40

Author(s):

P.G. Suraj ◽

K. Nagabhushana ◽

R. Kamalakannan ◽

M. Varghese

Keyword(s):

Genetic Diversity ◽

Population Size ◽

Effective Population Size ◽

Second Generation ◽

Gene Diversity ◽

Eucalyptus Camaldulensis ◽

Phenotypic Traits ◽

Effective Population ◽

Fertility Variation ◽

The Impact

Abstract Fertility and gene diversity were estimated in three second generation (F2) seed stands (SPA 1-3) and two clone trials (CSO 1&2) of Eucalyptus camaldulensis to assess the impact on seed crop. F2 seedlots were evaluated in comparison to native provenances, ten commercial clones and interspecific hybrids at diverse sites. SPA 1&2 were genetic gain trials of five first generation (F1) orchard seedlots, SPA 3 a plantation of one F1 orchard seedlot, and CSOs were clone trials of 21 commercial clones established at two contrasting sites. Fertility variation, as indicated by sibling coefficient, was high (Ψ, 9-14) in the SPAs as only about 26 % trees were fertile compared to 81 % trees in CSOs. Effective population size was higher in SPA 1 and 2 (Ns, 95 and 74, respectively) than SPA 3 (Ns = 39). Fertility was highly skewed in CSO 2 resulting in low effective population size (Ns = 2) compared to CSO 1 (Ns = 11). Constant seed collection enabled 3-fold increase in relative population size and 22 % higher predicted gene diversity in CSO 2. Genetic diversity (He) estimated using SSR markers was higher in SPA 1&2 and native provenances (NAT), compared to SPA 3 and CSO 1, whereas CSO 2 and clones had lower values. There was a high positive correlation between estimated He and predicted gene diversity values of SPAs and CSOs. He was positively correlated to mean field survival and negatively correlated to kraft pulp yield (KPY), evaluated at three years in progeny trials across three locations. Number of alleles per locus was higher in SPAs and native provenances compared to CSOs and clones. Discriminant principal component analysis clustered CSO, NAT and SPA seedlots in different groups while commercial E. camaldulensis clones clustered close to NAT. Multilocus outcrossing rate was generally high (tm, 91-100 %), though selfing was observed in two families of SPA 3 and CSO 2. Selected interspecific hybrid families of commercial E. camaldulensis clones (with E. urophylla and E. pellita) evaluated at two of the sites had higher He and KPY than clones at three years.

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Editorial

The Lichenologist ◽

10.1017/s0024282905990014 ◽

2005 ◽

Vol 37 (5) ◽

pp. 371-372

Author(s):

Peter D. Crittenden ◽

Richard P. Beckett ◽

Dianne Fahselt

Keyword(s):

Genetic Diversity ◽

Microbial Diversity ◽

Genetic Control ◽

Secondary Metabolite ◽

International Association ◽

Breeding Systems ◽

Metabolite Production ◽

Lichen Thallus ◽

Poster Presentations ◽

Oral Presentations

Between 16–21 August 2004, 250 lichenologists gathered in Tartu, Estonia for the Fifth Symposium of the International Association for Lichenology (IAL5). The meeting comprised six principal lecture sessions and associated posters. This issue of The Lichenologist presents papers deriving from contributions to Session 3: Genes, Physiology and Structure. This session probably had the broadest scope of all those comprising the symposium because it essentially encompassed all aspects of the general biology of the lichen thallus. The response to this topic from prospective authors and presenters was excellent and the final programme included fourteen oral presentations and sixteen posters; of this total of thirty contributions, eight are published here. Inevitably, several of the oral and poster presentations were already submitted to, or destined for, alternative journals or were considered too preliminary to warrant publication at this stage. In particular, there were several excellent “molecular” contributions dealing with such topics as breeding systems, genetic diversity, microbial diversity within thalli, and the genetic control of secondary metabolite production, but none were available or offered as papers to this volume.

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Study on Properties of Carbon Nanotubes/Epoxy Resin Composite Prepared by In Situ Polymerization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.132 ◽

2013 ◽

Vol 750-752 ◽

pp. 132-135 ◽

Cited By ~ 1

Author(s):

Zhang Yue ◽

Mei Yan Yu ◽

Xi Lan

Keyword(s):

Carbon Nanotubes ◽

Impact Strength ◽

Epoxy Resin ◽

Resin Composite ◽

Weight Ratio ◽

Fracture Pattern ◽

Epoxy Resin Composite ◽

The Impact ◽

Hydroxy Groups

Carbon nanotubes (CNTs) treated with an alkali solution were used to toughen epoxy resin (EP) by in-situ polymerization.The effects of different CNTs contents on the impact strength of EP were discussed. The morphology of impact section was investigated too.The results indicated that a certain amount of hydroxy groups were introduced on the surface of CNTs.The impact strength of EP is greatly enhanced with the increase of CNTs/EP weight ratio, and exhibited a maximum when ratio was 0.5.The toughness of CNTs/EP composites was remarkably improved.SEM showed that the fracture pattern of CNTs/EP composites was changed from brittle fracture to ductile fracture.

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In situ Quantification of the Impact of Episodic Enhanced Turbulent Events in Large Phytoplankton

10.21236/ada598366 ◽

2011 ◽

Author(s):

Percy L. Donaghay ◽

Jan Rines ◽

James Sullivan

Keyword(s):

The Impact

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Trends in genetic diversity and the effect of inbreeding in American Angus cattle under genomic selection

Genetics Selection Evolution ◽

10.1186/s12711-021-00644-z ◽

2021 ◽

Vol 53 (1) ◽

Author(s):

Emmanuel A. Lozada-Soto ◽

Christian Maltecca ◽

Duc Lu ◽

Stephen Miller ◽

John B. Cole ◽

...

Keyword(s):

Genetic Diversity ◽

Beef Cattle ◽

Genomic Selection ◽

Inbreeding Depression ◽

Growth Traits ◽

Effective Population ◽

Angus Cattle ◽

Genomic Inbreeding ◽

Chromosome Segments ◽

The Impact

Abstract Background While the adoption of genomic evaluations in livestock has increased genetic gain rates, its effects on genetic diversity and accumulation of inbreeding have raised concerns in cattle populations. Increased inbreeding may affect fitness and decrease the mean performance for economically important traits, such as fertility and growth in beef cattle, with the age of inbreeding having a possible effect on the magnitude of inbreeding depression. The purpose of this study was to determine changes in genetic diversity as a result of the implementation of genomic selection in Angus cattle and quantify potential inbreeding depression effects of total pedigree and genomic inbreeding, and also to investigate the impact of recent and ancient inbreeding. Results We found that the yearly rate of inbreeding accumulation remained similar in sires and decreased significantly in dams since the implementation of genomic selection. Other measures such as effective population size and the effective number of chromosome segments show little evidence of a detrimental effect of using genomic selection strategies on the genetic diversity of beef cattle. We also quantified pedigree and genomic inbreeding depression for fertility and growth. While inbreeding did not affect fertility, an increase in pedigree or genomic inbreeding was associated with decreased birth weight, weaning weight, and post-weaning gain in both sexes. We also measured the impact of the age of inbreeding and found that recent inbreeding had a larger depressive effect on growth than ancient inbreeding. Conclusions In this study, we sought to quantify and understand the possible consequences of genomic selection on the genetic diversity of American Angus cattle. In both sires and dams, we found that, generally, genomic selection resulted in decreased rates of pedigree and genomic inbreeding accumulation and increased or sustained effective population sizes and number of independently segregating chromosome segments. We also found significant depressive effects of inbreeding accumulation on economically important growth traits, particularly with genomic and recent inbreeding.

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Reciprocal hemizygosity analysis reveals that the Saccharomyces cerevisiae CGI121 gene affects lag time duration in synthetic grape must

G3 Genes|Genome|Genetics ◽

10.1093/g3journal/jkab061 ◽

2021 ◽

Author(s):

Runze Li ◽

Rebecca C Deed

Keyword(s):

Saccharomyces Cerevisiae ◽

Low Temperatures ◽

Lag Time ◽

Lag Phase ◽

Phenotypic Traits ◽

Time Duration ◽

Phase Duration ◽

Grape Must ◽

The Impact ◽

Reciprocal Hemizygosity Analysis

Abstract It is standard practice to ferment white wines at low temperatures (10-18 °C). However, low temperatures increase fermentation duration and risk of problem ferments, leading to significant costs. The lag duration at fermentation initiation is heavily impacted by temperature; therefore, identification of Saccharomyces cerevisiae genes influencing fermentation kinetics is of interest for winemaking. We selected 28 S. cerevisiae BY4743 single deletants, from a prior list of open reading frames (ORFs) mapped to quantitative trait loci (QTLs) on chromosomes VII and XIII, influencing the duration of fermentative lag time. Five BY4743 deletants, Δapt1, Δcgi121, Δclb6, Δrps17a, and Δvma21, differed significantly in their fermentative lag duration compared to BY4743 in synthetic grape must (SGM) at 15 °C, over 72 h. Fermentation at 12.5 °C for 528 h confirmed the longer lag times of BY4743 Δcgi121, Δrps17a, and Δvma21. These three candidate ORFs were deleted in S. cerevisiae RM11-1a and S288C to perform single reciprocal hemizygosity analysis (RHA). RHA hybrids and single deletants of RM11-1a and S288C were fermented at 12.5 °C in SGM and lag time measurements confirmed that the S288C allele of CGI121 on chromosome XIII, encoding a component of the EKC/KEOPS complex, increased fermentative lag phase duration. Nucleotide sequences of RM11-1a and S288C CGI121 alleles differed by only one synonymous nucleotide, suggesting that intron splicing, codon bias, or positional effects might be responsible for the impact on lag phase duration. This research demonstrates a new role of CGI121 and highlights the applicability of QTL analysis for investigating complex phenotypic traits in yeast.

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Genotyping Strategies Using ddRAD Sequencing in Farmed Arctic Charr (Salvelinus alpinus)

Animals ◽

10.3390/ani11030899 ◽

2021 ◽

Vol 11 (3) ◽

pp. 899

Author(s):

Fotis Pappas ◽

Christos Palaiokostas

Keyword(s):

Genetic Diversity ◽

Salvelinus Alpinus ◽

Arctic Charr ◽

Cost Effective ◽

Limiting Factors ◽

Phenotypic Traits ◽

Production Volume ◽

High Coverage ◽

Genomic Relationships ◽

Low Coverage

Incorporation of genomic technologies into fish breeding programs is a modern reality, promising substantial advances regarding the accuracy of selection, monitoring the genetic diversity and pedigree record verification. Single nucleotide polymorphism (SNP) arrays are the most commonly used genomic tool, but the investments required make them unsustainable for emerging species, such as Arctic charr (Salvelinus alpinus), where production volume is low. The requirement to genotype a large number of animals for breeding practices necessitates cost effective genotyping approaches. In the current study, we used double digest restriction site-associated DNA (ddRAD) sequencing of either high or low coverage to genotype Arctic charr from the Swedish national breeding program and performed analytical procedures to assess their utility in a range of tasks. SNPs were identified and used for deciphering the genetic structure of the studied population, estimating genomic relationships and implementing an association study for growth-related traits. Missing information and underestimation of heterozygosity in the low coverage set were limiting factors in genetic diversity and genomic relationship analyses, where high coverage performed notably better. On the other hand, the high coverage dataset proved to be valuable when it comes to identifying loci that are associated with phenotypic traits of interest. In general, both genotyping strategies offer sustainable alternatives to hybridization-based genotyping platforms and show potential for applications in aquaculture selective breeding.

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