Germplasm conservation and agriculture

Abstract Background Rice, the most important crop in Asia, has been cultivated in Taiwan for more than 5000 years. The landraces preserved by indigenous peoples and brought by immigrants from China hundreds of years ago exhibit large variation in morphology, implying that they comprise rich genetic resources. Breeding goals according to the preferences of farmers, consumers and government policies also alter gene pools and genetic diversity of improved varieties. To unveil how genetic diversity is affected by natural, farmers’, and breeders’ selections is crucial for germplasm conservation and crop improvement. Results A diversity panel of 148 rice accessions, including 47 cultivars and 59 landraces from Taiwan and 42 accessions from other countries, were genotyped by using 75 molecular markers that revealed an average of 12.7 alleles per locus with mean polymorphism information content of 0.72. These accessions could be grouped into five subpopulations corresponding to wild rice, japonica landraces, indica landraces, indica cultivars, and japonica cultivars. The genetic diversity within subpopulations was: wild rices > landraces > cultivars; and indica rice > japonica rice. Despite having less variation among cultivars, japonica landraces had greater genetic variation than indica landraces because the majority of Taiwanese japonica landraces preserved by indigenous peoples were classified as tropical japonica. Two major clusters of indica landraces were formed by phylogenetic analysis, in accordance with immigration from two origins. Genetic erosion had occurred in later japonica varieties due to a narrow selection of germplasm being incorporated into breeding programs for premium grain quality. Genetic differentiation between early and late cultivars was significant in japonica (FST = 0.3751) but not in indica (FST = 0.0045), indicating effects of different breeding goals on modern germplasm. Indigenous landraces with unique intermediate and admixed genetic backgrounds were untapped, representing valuable resources for rice breeding. Conclusions The genetic diversity of improved rice varieties has been substantially shaped by breeding goals, leading to differentiation between indica and japonica cultivars. Taiwanese landraces with different origins possess various and unique genetic backgrounds. Taiwanese rice germplasm provides diverse genetic variation for association mapping to unveil useful genes and is a precious genetic reservoir for rice improvement.

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In vitro propagation and cytological analysis of Sophora mollis Royle: an endangered medicinal shrub

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00140-3 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Aakriti Bhandari ◽

Harminder Singh ◽

Amber Srivastava ◽

Puneet Kumar ◽

G. S. Panwar ◽

...

Keyword(s):

Chromosome Number ◽

Average Length ◽

Germplasm Conservation ◽

Basic Chromosome Number ◽

Shoot Tip ◽

Ex Situ ◽

Ms Medium ◽

Basic Chromosome ◽

Shoot Tip Explants

Abstract Background Sophora mollis Royle (family Fabaceae, subfamily-Papilionaceae) is a multipurpose legume distributed in plains and foothills of the North-West Himalaya to Nepal and is facing high risk of extinction due to habitat loss and exploitation by the local people for its fuel and fodder values. Therefore, the present study was conducted to standardize a micropropagation protocol for Sophora mollis by using shoot tip explants and to study the meiotic chromosome count in the species. Results Multiple shoots were induced in shoot tip explants of Sophora mollis in Murashige and Skoog medium supplemented with different concentrations of cytokinins alone (BAP, TDZ, and Kinetin) and in combination with varying concentrations of NAA. MS medium supplemented with BAP (8.9 μM) was observed to be the optimal medium for multiple shoot induction and maximum 25.32 shoots per explant was obtained with average length of 4.5 ± 0.8 cm. In vitro developed shoots were transferred onto rooting media supplemented with different concentrations of auxin (IAA, IBA, and NAA). Maximum 86% rooting was observed in half-strength MS medium supplemented with 21.20 μM NAA with an average of 21.26 roots per culture. In vitro raised plantlets were adapted to greenhouse for better acclimatization and 60% plants were successfully transferred to the open environment. Based on the chromosome counts available from the literature and the current study, the species tend to show a basic chromosome number of x = 9. Conclusion The micropropagation protocol standardized can be helpful for the ex situ mass multiplication and germplasm conservation of the endangered species. Moreover, the ex situ conservation approach will be helpful in actively bridging the gap between ex situ and in situ approaches through the reintroduction of species in the wild. The cytological studies revealed the basic chromosome number x = 9 of the species.

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Germplasm Conservation: Instrumental in Agricultural Biodiversity—A Review

Sustainability ◽

10.3390/su13126743 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6743

Author(s):

Veerala Priyanka ◽

Rahul Kumar ◽

Inderpreet Dhaliwal ◽

Prashant Kaushik

Keyword(s):

Plant Species ◽

Agricultural Production ◽

Genetic Instability ◽

Slow Growth ◽

Germplasm Conservation ◽

Agricultural Biodiversity ◽

Genetic Composition ◽

In Vitro Techniques ◽

Protection Strategies

Germplasm is a valuable natural resource that provides knowledge about the genetic composition of a species and is crucial for conserving plant diversity. Germplasm protection strategies not only involve rescuing plant species threatened with extinction, but also help preserve all essential plants, on which rests the survival of all organisms. The successful use of genetic resources necessitates their diligent collection, storage, analysis, documentation, and exchange. Slow growth cultures, cryopreservation, pollen and DNA banks, botanical gardens, genetic reserves, and farmers’ fields are a few germplasm conservation techniques being employed. However, the adoption of in-vitro techniques with any chance of genetic instability could lead to the destruction of the entire substance, but the improved understanding of basic regeneration biology would, in turn, undoubtedly increase the capacity to regenerate new plants, thus expanding selection possibilities. Germplasm conservation seeks to conserve endangered and vulnerable plant species worldwide for future proliferation and development; it is also the bedrock of agricultural production.

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All Populations Matter: Conservation Genomics of Australia’s Iconic Purple Wattle, Acacia purpureopetala

Diversity ◽

10.3390/d13040139 ◽

2021 ◽

Vol 13 (4) ◽

pp. 139

Author(s):

Marlien M. van der Merwe ◽

Jia-Yee S. Yap ◽

Peter D. Wilson ◽

Helen T. Murphy ◽

Andrew Ford

Keyword(s):

Genetic Diversity ◽

Allelic Variation ◽

Germplasm Conservation ◽

Snp Markers ◽

Genomic Diversity ◽

Ex Situ ◽

Spatial Distance ◽

Genetic Connectivity ◽

Conservation Genomics ◽

Modelling Framework

Maximising genetic diversity in conservation efforts can help to increase the chances of survival of a species amidst the turbulence of the anthropogenic age. Here, we define the distribution and extent of genomic diversity across the range of the iconic but threatened Acacia purpureopetala, a beautiful sprawling shrub with mauve flowers, restricted to a few disjunct populations in far north Queensland, Australia. Seed production is poor and germination sporadic, but the species occurs in abundance at some field sites. While several thousands of SNP markers were recovered, comparable to other Acacia species, very low levels of heterozygosity and allelic variation suggested inbreeding. Limited dispersal most likely contributed towards the high levels of divergence amongst field sites and, using a generalised dissimilarity modelling framework amongst environmental, spatial and floristic data, spatial distance was found to be the strongest factor explaining the current distribution of genetic diversity. We illustrate how population genomic data can be utilised to design a collecting strategy for a germplasm conservation collection that optimises genetic diversity. For this species, inclusion of all field sites will capture maximum genetic diversity for both in situ and ex situ conservation. Assisted cross pollination, within and between field sites and genetically structured groups, is recommended to enhance heterozygosity particularly at the most disjunct sites and further fragmentation should be discouraged to avoid loss of genetic connectivity.

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Genetic diversity of fringed brome (Bromus ciliatus) as determined by amplified fragment length polymorphism

Canadian Journal of Botany ◽

10.1139/b05-112 ◽

2005 ◽

Vol 83 (10) ◽

pp. 1322-1328 ◽

Cited By ~ 12

Author(s):

Yong-Bi Fu ◽

Bruce E. Coulman ◽

Yasas S.N. Ferdinandez ◽

Jacques Cayouette ◽

Paul M. Peterson

Keyword(s):

Genetic Diversity ◽

Length Polymorphism ◽

Fragment Length ◽

Habitat Restoration ◽

Fragment Length Polymorphism ◽

Natural Populations ◽

Germplasm Conservation ◽

Amplified Fragment Length Polymorphism ◽

Large Area ◽

Geographic Origins

Fringed brome ( Bromus ciliatus L.) is found in native stands throughout a large area of North America. Little is known about the genetic diversity of this species. The amplified fragment length polymorphism (AFLP) technique was applied to assess the genetic diversity of 16 fringed brome populations sampled in Canada from the provinces of Alberta, British Columbia, Quebec, and Saskatchewan. Four AFLP primer pairs were employed to screen 82 samples with four to six samples per population and 83 polymorphic AFLP bands scored for each sample. The frequencies of the scored bands in all assayed samples ranged from 0.01 to 0.99 and averaged 0.53. Analysis of molecular variance revealed that 52.6% of the total AFLP variation resided among the 16 populations and 20.6% among the four provinces. The five Quebec populations appeared to be genetically the most diverse and distinct. The AFLP variability observed was significantly associated with the geographic origins of the fringed brome populations. These findings are useful for sampling fringed brome germplasm from natural populations for germplasm conservation and should facilitate the development of genetically diverse regional cultivars for habitat restoration and revegetation.

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Ampelographic characterization of white grapevine cul-tivars (Vitis vinifera L.) grown in Palestine

مجلة جامعة فلسطين التقنية للأبحاث ◽

10.53671/pturj.v3i1.34 ◽

2015 ◽

Vol 3 (1) ◽

pp. 1-11

Author(s):

Rezq Basheer-Salimia

Keyword(s):

Genetic Diversity ◽

Genetic Distance ◽

Germplasm Conservation ◽

Genetic Distances ◽

Vitis Vinifera L ◽

Similarity Matrix ◽

Breeding Programs ◽

Local Varieties ◽

Synonymies And Homonymies

Abstract: In Palestine, grape culture consists of ecotypes and cultivars (also called local varieties), for which a large number of homonymous and synonymous designations exist as well as misnaming of cultivars. The present study is the first report using detailed ampelographic characterizations (39 informative traits) to assess genetic diversity and detect similarities among sixteen accessions collected from putative diverse grape genotypes In general, 30 descriptors presented highly and satisfactory divergent genotypes, whereas the remaining traits showed no or very little ampelographic variation. Based on the similarity matrix and the resulting dendrogram of these ampelographic data, distinguishable genotypes as well as some cases of synonymies and homonymies clearly exist. A synonymy case seemed to be in four genotypes including Jandali-Mfarad, Jan-dali-Mrazraz, Jandali, and Hamadani-Mattar, which indeed showed genetic distances of less than 0.5, sug-gesting their relatedness, and the possibility that they are the same genotype, but with different names. In addition, homonym cases also occur in the following pairs of “Marawi’s, Hamadani’s, and Zaini’s genotypes, in which each pair seems to be two distinctive genotypes. Finally, among the 16 examined genotypes, the Zaini-Baladi genotype tended to show the highest genetic distance values from the others and thus could be potentially incorporated into any further local or regional breeding programs as well as germplasm conservation.

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