Selective Diversification of Aquaculture Stocks: A Proposal for Economically Sustainable Genetic Conservation

1991 ◽  
Vol 48 (S1) ◽  
pp. 148-154 ◽  
Author(s):  
R. W. Doyle ◽  
N. L. Shackel ◽  
Z. Basiao ◽  
S. Uraiwan ◽  
T. Matricia ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
National Level ◽  
Economic Benefits ◽  
Conservation Strategy ◽  
Environment Interaction ◽  
Production Traits ◽  
Local Environments ◽  
Genotype Frequencies ◽  
Genetic Impact ◽  
Breeding Programmes

The genetic diversity of aquaculture stocks can be maintained, and their genetic impact on wild stocks minimized, by breeding programmes that deliberately generate genetic diversity. Current animal breeding practices are likely to reduce the diversity of domestic stocks if they are extended to aquaculture. It is proposed that national breeding programmes for aquaculture should, instead, try to develop numerous breeds specially adapted to local environments and aquaculture systems. An economic model is presented of decision-making by individual farmers who, in choosing which breed to produce, determine the "fitness" of the breeds in a meta-population that includes all breeds. As long as strong genotype-environment interaction for production traits is maintained by artificial selection, the economic self-interest of farmers should ensure the stability of genetic polymorphisms among breeds. Genetic variation would be conserved (in the among-breed component of genetic diversity) but not the primordial distribution of gene and genotype frequencies. Economic benefits to farmers, plus a high return on investment at the national or supra-national level, makes breed diversification an attractive conservation strategy even though it is admittedly a compromise from a purely genetic viewpoint.

Designing genetic impact assessment for crossbreeding with exotic beef breeds in mixed farming systems

2020 ◽  
pp. 003072702091520 ◽  
Author(s):  
Tri Satya Mastuti Widi ◽  
Henk Udo ◽  
Kor Oldenbroek ◽  
I Gede Suparta Budisatria ◽  
Endang Baliarti ◽  
...  
Keyword(s):  
Impact Assessment ◽  
National Level ◽  
Farming Systems ◽  
Economic Benefits ◽  
Meat Production ◽  
Group Discussions ◽  
Central Java ◽  
Cattle Management ◽  
Genetic Impact ◽  
Local Farm

A genetic impact assessment (GIA) methodology is developed, consisting of consultation of stakeholders, identification of issues and assessment of associated indicators, for crossbreeding with exotic beef breeds in smallholder mixed farms. The GIA is implemented in two case studies of crossbreeding with Limousin and Simmental in Madura and Central Java, Indonesia. Consultation of stakeholders ( n = 421) in focus group discussions yielded the issues that should be taken into account in a GIA. Farmers identified economic benefits, feed availability, cattle management, animal’s performances, additional functions of cattle, and health and fertility as issues. Policymakers mentioned the production of beef as the main issue while scientists called for environmental quality and maintaining local farm animal genetic resources as issues. Indicators to characterize these issues in a GIA were deducted from literature; determination of the indicators was based on data sampled on 97 farms, keeping local Madura or Limousin crossbreds, in Madura and 252 farms and keeping local Ongole or Simmental crossbreds, in Central Java. The GIA showed that crossbreeding contributes to increased meat production at the national level; however, it does not necessarily guarantee improvements in economic benefits at farm level nor environmental performances.

Genetic diversity of mungbean (Vigna radiata L.) germplasm in Indonesia

2014 ◽  
Vol 12 (S1) ◽  
pp. S91-S94 ◽  
Author(s):  
Puji Lestari ◽  
Sue Kyung Kim ◽  
Reflinur ◽  
Yang Jae Kang ◽  
Nurwita Dewi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Ssr Markers ◽  
Vigna Radiata ◽  
Diversity Index ◽  
Polymorphic Information Content ◽  
Conservation Strategy ◽  
Low Genetic Diversity ◽  
Breeding Programmes ◽  
The Mean ◽  
Simple Sequence

Despite widespread mungbean [Vigna radiata (L.) Wilczek] consumption in Indonesia, few molecular studies have been carried out on accessions and available data are minimal. In this study, we used 30 newly developed simple sequence repeat (SSR) markers designed from the mapped sequence scaffolds of the Korean Sunhwanokdu and Gyeonggijaerae 5 mungbean genomes. These markers were used to examine loci in 83 mungbean accessions collected from diverse geographical areas in Indonesia. A total of 107 alleles were detected among the accessions with 29 polymorphic markers. However, the mean of polymorphic information content (0.33) value and diversity index (0.38) value was indicative of low genetic diversity in this germplasm. The mungbean population structure was not clearly differentiated and the number of subpopulations was unclear. Neighbour-joining tree analysis revealed that the genetic cluster did not reflect the geographical origin of the accessions. Interestingly, the most agriculturally improved varieties were genetically similar to some landraces from one of the main mungbean-producing regions. These newly developed SSR markers could be useful for detecting genetic variability as a basis for establishing a conservation strategy for mungbean germplasm with the aim of enhancing Indonesian breeding programmes.

PROFILING OF GUAVA GENOTYPES GROWN IN VIDARBHA CONDITIONS ON THE BASIS OF MORPHOLOGICAL TRAITS

2017 ◽  
Vol 23 (1) ◽  
Author(s):  
R.A. PATIL ◽  
S.G. BHARAD ◽  
S.N. SAWANT
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Morphological Traits ◽  
Considerable Extent ◽  
Fruit Traits ◽  
Breeding Programmes ◽  
Tree Leaf ◽  
Qualitative Characteristics ◽  
Intrapopulation Diversity

Assessment of genetic diversity in the available germplasm is the prerequisite for development of improved genotypes through planned breeding programmes. In the view of this Forty-eight genotypes of seedling origin guava along with 1 check (L-49/Sardar) collected and conserved at germplasm block, Main Garden, Department of Horticulture, Dr. P. D. A. University, Akola were evaluated for genetic variability and diversity based on the qualitative characteristics. The genotypes were evaluated for sixteen morphological traitsviz. tree, leaf, floral and fruit traits. Results Show considerable extent of variability amongst the 49 genotypes in each traits. A sizeable amount of intrapopulation diversity recorded can be used to identify diverse parents which can be utilized in hybridization programmes.

Genetic diversity of native cultivated cacao accessions (Theobroma cacao L.) in Nicaragua

2012 ◽  
Vol 10 (3) ◽  
pp. 254-257
Author(s):  
Erwin Aragon ◽  
Claudia Rivera ◽  
Helena Korpelainen ◽  
Aldo Rojas ◽  
Paula Elomaa ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Theobroma Cacao ◽  
Phytophthora Palmivora ◽  
Genetic Composition ◽  
Breeding Programmes ◽  
Black Pod ◽  
Black Pod Disease ◽  
Parental Lines ◽  
Resistant Genotypes ◽  
Theobroma Cacao L

A total of 60 farmers' cacao accessions (Theobroma cacao L.) from Nicaragua were investigated using microsatellite markers to reveal their genetic composition and to identify potentially resistant genotypes against the black pod disease caused by Phytophthora palmivora. These accessions were compared with 21 breeders' accessions maintained locally, two Criollo accessions from Costa Rica and two accessions from Ecuador. The analyses showed a low level of differentiation among groups of farmers' accessions (FST = 0.06) and that six Nicaraguan accessions were genetically closely related to the two Criollo accessions used as a reference. In addition, seven distinct genotypes were found to have allelic composition that may indicate linkage to resistance alleles, thus being potential parental lines in future breeding programmes.

Reducing the Impact of Unemployment through Work-Sharing: Some Industrial Relations Considerations

1983 ◽  
Vol 25 (2) ◽  
pp. 153-161 ◽  
Author(s):  
Noah M. Meltz ◽  
Frank Reid
Keyword(s):  
Local Level ◽  
Industrial Relations ◽  
National Level ◽  
Economic Benefits ◽  
Firm Level ◽  
Labour Relations ◽  
Work Sharing ◽  
Long Run ◽  
Short Run ◽  
The Impact

The Canadian Government has introduced a work-sharing program in which lay offs are avoided by reducing the work week and using unemployment insurance funds to pay workers short-time compensation. Compared to the lay-off alternative, there appear to be economic benefits to work-sharing for both management and employees. Reaction to the scheme has been generally positive at the union local level and the firm level, but it has been negative at the national level of both labour and management. These divergent views can be explained mainly as a result of short-run versus long-run perspectives. Managers at the firm level see the immediate benefit of improved labour relations and the avoidance of the costs of hiring and training replacements for laid-off workers who do not respond when recalled. The national business leaders are more concerned with work incentive and efficiency aspects of work-sharing.

scholarly journals The new use of Sorghum bicolor-derived SSR markers to evaluate genetic diversity in 17 Australian Sorghum species

2005 ◽  
Vol 3 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Sally L. Dillon ◽  
Peter K. Lawrence ◽  
Robert J. Henry
Keyword(s):  
Genetic Diversity ◽  
Sorghum Bicolor ◽  
Ssr Markers ◽  
Diversity Indices ◽  
Basic Knowledge ◽  
Apparent Lack ◽  
Breeding Programmes ◽  
Diversity Studies ◽  
Potential Use ◽  
Simple Sequence

The Sorghum genus is extremely diverse both morphologically and geographically, however, relatively few of the 25 recognized species have been evaluated genetically. The apparent lack of basic knowledge pertaining to the levels of genetic diversity both within and between the 17 Australian wild species is a major obstacle to both their effective conservation and potential use in breeding programmes. Twelve Sorghum bicolor-derived simple sequence repeat (SSR) markers were evaluated for cross-species amplification in all 25 Sorghum species. The SSR markers were highly polymorphic, with diversity indices ranging from 0.59 to 0.99 with mean of 0.91. Five markers combined were able to differentiate 24 of the 25 Sorghum species, with intra-species polymorphism apparent. Sorghum bicolor-derived SSRs have proven to be an efficient source of markers for genetic diversity studies of the relatively poorly characterized Australian indigenous Sorghum species.

Overt and Concealed Genetic Loads Revealed by QTL Mapping of Genotype-dependent Viability in the Pacific Oyster Crassostrea gigas

Genetics ◽  
2021 ◽  
Author(s):  
Xiaoshen Yin ◽  
Dennis Hedgecock
Keyword(s):  
Genetic Diversity ◽  
Crassostrea Gigas ◽  
Pacific Oyster ◽  
Genetic Load ◽  
High Density ◽  
High Genetic Diversity ◽  
High Fecundity ◽  
Recessive Mutations ◽  
Genotype Frequencies ◽  
The Pacific

Abstract Understanding the genetic bases of inbreeding depression, heterosis, and genetic load is integral to understanding how genetic diversity is maintained in natural populations. The Pacific oyster Crassostrea gigas, like many long-lived plants, has high fecundity and high early mortality (type-III survivorship), manifesting a large, overt, genetic load; the oyster harbors an even greater concealed genetic load revealed by inbreeding. Here, we map viability QTL (vQTL) in six interrelated F2 oyster families, using high-density linkage maps of single nucleotide polymorphisms generated by genotyping-by-sequencing (GBS) methods. Altogether, we detect 70 vQTL and provisionally infer 89 causal mutations, 11 to 20 per family. Genetic mortality caused by independent (unlinked) vQTL ranges from 94.2% to 97.8% across families, consistent with previous reports. High-density maps provide better resolution of genetic mechanisms, however. Models of one causal mutation present in both identical-by-descent (IBD) homozygotes and heterozygotes fit genotype frequencies at 37 vQTL; consistent with the mutation-selection balance theory of genetic load, 20 are highly deleterious, completely recessive mutations and 17 are less deleterious, partially dominant mutations. Another 22 vQTL require pairs of recessive or partially dominant causal mutations, half showing selection against recessive mutations linked in repulsion, producing pseudo-overdominance. Only eight vQTL appear to support the overdominance theory of genetic load, with deficiencies of both IBD homozygotes, but at least four of these are likely caused by pseudo-overdominance. Evidence for epistasis is absent. A high mutation rate, random genetic drift, and pseudo-overdominance may explain both the oyster’s extremely high genetic diversity and a high genetic load maintained primarily by mutation-selection balance.

scholarly journals AUTOCHTHONOUS BREEDS OF DOMESTIC ANIMALS AND CONSERVATION MEASURES

AGROFOR ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Zoran MALETIC
Keyword(s):  
Genetic Diversity ◽  
Biological Diversity ◽  
Domestic Animals ◽  
Conservation Strategy ◽  
Ex Situ ◽  
Animal Genetic Resources ◽  
Diversity Preservation ◽  
The Republic ◽  
International Conventions

Recently, highly productive breeds of various species of domestic animals have been used in livestock production, which has resulted in the destruction of indigenous breeds of domestic animals around the world, even in our area. This is the first reason why indigenous races and strains have been endangered. Another reason is that domestic, indigenous breeds were crossed with specialized breeds, which were imported, and in that way their genetic diversity was negatively affected. Resistance is lost, adaptation to the conditions in which they were created, the ability to survive in nature. Indigenous breeds of different species of domestic animals, which are recognized in the Republic of Srpska (BiH) are gatačko cattle and buša (cattle), Vlašić pramenka, Podveleška pramenka, Kupres pramenka (sheep), domestic Balkan horned goat (goats), Bosnian mountain horse (horses), mangulica (pigs) and pogrmuša hen or živičarka hen (poultry). By acceding to international conventions, BiH /Republic of Srpska has committed itself to establishing a system of measures that will enable the conservation of biological diversity and the protection of indigenous and endangered breeds of domestic animals. The choice of a strategy for the conservation of diversity, the establishment of an adequate conservation scheme, and the implementation of a conservation strategy are some of the key elements of any process for the conservation of genetic diversity. Preservation of autochthonous and protected breeds of domestic animals is possible through preservation in the original environment (in situ) and preservation outside the original environment (ex situ). There is a possibility of combining these models of conservation of animal genetic resources.

scholarly journals Molecular characterization and genetic diversity studies of Indian soybean (Glycine max (L.) Merr.) cultivars using SSR markers

2021 ◽  
Author(s):  
S. P. Jeevan Kumar ◽  
C. Susmita ◽  
K. V. Sripathy ◽  
Dinesh K. Agarwal ◽  
Govind Pal ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Molecular Characterization ◽  
Ssr Markers ◽  
Crop Yield ◽  
Gene Pool ◽  
Stress Factors ◽  
Soybean Cultivars ◽  
Genetic Base ◽  
Purity Analysis ◽  
Breeding Programmes

Abstract Background The genetic base of soybean cultivars in India has been reported to be extremely narrow, due to repeated use of few selected and elite genotypes as parents in the breeding programmes. This ultimately led to the reduction of genetic variability among existing soybean cultivars and stagnation in crop yield. Thus in order to enhance production and productivity of soybean, broadening of genetic base and exploring untapped valuable genetic diversity has become quite indispensable. This could be successfully accomplished through molecular characterization of soybean genotypes using various DNA based markers. Hence, an attempt was made to study the molecular divergence and relatedness among 29 genotypes of soybean using SSR markers. Methods and results A total of 35 SSR primers were deployed to study the genetic divergence among 29 genotypes of soybean. Among them, 14 primer pairs were found to be polymorphic producing a total of 34 polymorphic alleles; and the allele number for each locus ranged from two to four with an average of 2.43 alleles per primer pair. Polymorphic information content (PIC) values of SSRs ranged from 0.064 to 0.689 with an average of 0.331. The dendrogram constructed based on dissimilarity indices clustered the 29 genotypes into two major groups and four sub-groups. Similarly, principal coordinate analysis grouped the genotypes into four major groups that exactly corresponded to the clustering of genotypes among four sub-groups of dendrogram. Besides, the study has reported eight unique and two rare alleles that could be potentially utilized for genetic purity analysis and cultivar identification in soybean. Conclusion In the present investigation, two major clusters were reported and grouping of large number of genotypes in each cluster indicated high degree of genetic resemblance and narrow genetic base among the genotypes used in the study. With respect to the primers used in the study, the values of PIC and other related parameters revealed that the selected SSR markers are moderately informative and could be potentially utilized for diversity analysis of soybean. The clustering pattern of dendrogram constructed based on SSR loci profile displayed good agreement with the cultivar’s pedigree information. High level of genetic similarity observed among the genotypes from the present study necessitates the inclusion of wild relatives, land races and traditional cultivars in future soybean breeding programmes to widen the crop gene pool. Thus, hybridization among diverse gene pool could result in more heterotic combinations ultimately enhancing genetic gain, crop yield and resistance to various stress factors.

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