On-Farm Diversity and Genetic Erosion of Tetraploid Wheat Landraces in Ambo and Dandi Districts, West Shewa, Ethiopia

Interest in local landraces has unfortunately decreased over, the last decades, in which they have been continuously subjected to a high genetic erosion in favour of new modern varieties. Within the Puglia region (S-E Italy), Foggia province was found to be the richest in vegetable landraces. In the present study, six garlic landraces collected from this area have been assessed for their chemical composition (minerals, organic acids, free sugars, volatile, and phenolic compounds) along with their main morpho-biometrical traits. A commercial genotype was also considered as a reference standard. The landraces show a large variability, but in general high morphological standards, high levels of cations and phenols, and low levels of volatile-(S)-compounds in comparison with the commercial genotype and the literature values. ‘Aglio di Peschici’ and ‘Aglio Rosso di Monteleone di Puglia’ are very rich in minerals and phenols (mainly ferulic acid and iso-rhamnetin). This increase in knowledge on the chemical properties of these garlic landraces could represent a tool for encouraging the consumption of a food product. At the same time, the consumption of these landraces would stimulate their cultivation and could highly contribute to protection against the risk of erosion of agro-biodiversity by their in situ/on-farm conservation.

Download Full-text

Genetic diversity of high-molecular-weight glutenin subunit compositions in bread wheat landraces originated from Turkey

Plant Genetic Resources ◽

10.1017/s1479262116000356 ◽

2016 ◽

Vol 16 (1) ◽

pp. 28-38 ◽

Cited By ~ 1

Author(s):

Ridvan Temizgul ◽

Mikail Akbulut ◽

Domenico Lafiandra

Keyword(s):

Genetic Diversity ◽

Molecular Weight ◽

Genetic Variation ◽

High Molecular Weight ◽

Bread Wheat ◽

Gene Diversity ◽

Polyacrylamide Gel Electrophoresis ◽

Genetic Erosion ◽

Allele Polymorphism ◽

Wheat Landraces

AbstractFocusing on 116 bread wheat landraces, this study investigated high molecular weight glutenin allele polymorphism, gene diversity, genetic variation and linkage disequilibrium (LD) inGlu-1loci. To identify gluten alleles, sodium dodesyl sulphate-polyacrylamide, gel electrophoresis was used and for statistical analyses POPGENE software was employed. The results indicated that average genetic variation (h) was the highest inGlu-B1(0.6421) and the lowest inGlu-A1locus (0.4548); genetic similarity ratio (I) was the highest inGlu-B1(1.4170); the highest average genetic diversity (Ht) was observed inGlu-B1(0.6575) and the lowest diversity was observed inGlu-A1(0.4558). It was also observed that genetic diversity inGlu-1locus was largely due to intra-population variations. Inter-population gene flow was also calculated as 4.0051. Marmara and Southeastern Anatolia regions, the results further indicated, had the highest (2.8691) and lowest (0.1694) heterozygosity. Genetic erosion risk for Turkish bread wheat landraces was also seen to be high. Considering the mutual analyses of subunits of nationwide wheat landraces, it is possible to speculate about a limited migration between the landraces. LD of the landraces was largely because of this limited migration and/or epistatic natural selection. Since Turkey is known as the gene centre for major cereals including wheat, barley, rye and oat, where they diversified and spread throughout the world, studying the gluten allele diversity of Turkish bread wheat landraces is important. In addition, this study has revealed the applicability of LD, and neutrality tests to gluten protein diversity for the first time.

Download Full-text

Implications of farmers’ seed exchanges for on-farm conservation of quinoa, as revealed by its genetic diversity in Chile

The Journal of Agricultural Science ◽

10.1017/s0021859612000056 ◽

2012 ◽

Vol 150 (6) ◽

pp. 702-716 ◽

Cited By ~ 37

Author(s):

F. F. FUENTES ◽

D. BAZILE ◽

A. BHARGAVA ◽

E. A. MARTÍNEZ

Keyword(s):

Genetic Diversity ◽

Genetic Erosion ◽

Agricultural Practices ◽

Urban Systems ◽

Small Scale ◽

South American ◽

Exchange Networks ◽

On Farm Conservation ◽

Genetic Structure And Diversity ◽

On Farm

SUMMARYQuinoa cultivation in Chile presents an ancient and active complex of geographic, climatic, social and cultural interactions that has determined its current biodiversity in the three main growing zones (north, central and south). Importantly, these interactions involve the participation of farmers, whose activities are at the base of seed exchange networks due to their knowledge andin situconservation of genetic diversity. The present study reports how a better understanding of farmers’ seed exchanges and local production practices could impact the genetic structure and diversity of quinoa at national scale in Chile. Using field interviews and characterization of 20 microsatellite genetic markers in a multi-origin set of 34 quinoa accessions representative of Chile and the South American region, the phenetic analysis of germplasm was consistent with the current classification of quinoa ecotypes present in Chile and Andean zone. This allowed the identification of five populations, which were represented by quinoa of Salares (northern Chile), Coastal/Lowlands (central and southern Chile), Highlands (Peru, Bolivia and Argentina) and Inter-Andean Valleys (Ecuador and Colombia). The highly informative quality of the markers used revealed a wide genetic diversity among main growing areas in Chile, which correlated well with natural geographical–edaphic–climatic and social–linguistic context to the expansion of quinoa biodiversity. Additionally, in addition to ancient seed exchanges, this process is still governed by the diverse agricultural practices of Andean farmers. Genetic erosion is considered an imminent risk due to small-scale farming, where the influence of increased migration of people to urban systems and export-driven changes to the agro-ecosystems may further reduce the diversity of quinoa plants in cultivation.

Download Full-text

Estimation of genetic erosion on Ethiopian tetraploid wheat landraces using different approaches

Genetic Resources ◽

10.46265/genresj.pybz4246 ◽

2021 ◽

Vol 2 (4) ◽

pp. 66-71

Author(s):

Alemayehu Zemede Lemma ◽

Firew Mekbib ◽

Kebebew Assefa Abebe ◽

Zewdie Bishaw

Keyword(s):

Durum Wheat ◽

Tetraploid Wheat ◽

Genetic Erosion ◽

Wheat Varieties ◽

Central Ethiopia ◽

Growing Seasons ◽

Crop Varieties ◽

Field Assessment ◽

Loss Of Diversity ◽

Local Farmers

The demand and use of improved crop varieties by farmers has increased in the central highlands of Ethiopia, where continuous loss of local traditional varieties has been occurring in the last two to three decades. The objectives of the study were to assess the extent of genetic erosion and perception of farmers and associated causes for the reduction of traditional farmers' varieties. Direct field assessment covering 56 wheat farms and a survey in which 149 farmers participated were carried out in three districts of central Ethiopia. Based on data collected during direct farm assessment, the loss of genotypes was found to be 88% in Ada followed by 80% and 60% in Lume and Gimbichu districts, respectively. The farmer survey indicated an even greater loss of diversity of100% in Ada followed by Lume (93%) and Gimbichu (67%). Diseases and pests as well as shorter growing seasons associated with climate change were identified as main causes for farmers to switch to modern varieties. The expansion of high yielding improved bread and durum wheat varieties also contributed to gradually replace local durum wheat varieties by local farmers of these districts. Overall, genetic erosion of tetraploid wheat varied among the three districts of central Ethiopia. Reductions in the number of farmers and area coverage in the study districts could be used as good indicators for the existence of genetic erosion.

Download Full-text

Plant agrobiodiversity conservation and use in intensive farming systems: N-Italy as a case study.

10.21203/rs.3.rs-449495/v1 ◽

2021 ◽

Author(s):

Marco Canella ◽

Nicola M.G. Ardenghi ◽

Jonas V. Müller ◽

Graziano Rossi ◽

Filippo Guzzon

Keyword(s):

Ex Situ Conservation ◽

Plant Genetic Resources ◽

Conservation Status ◽

Genetic Erosion ◽

Northern Italy ◽

Crop Diversity ◽

Ex Situ ◽

Field Surveys ◽

Neglected Crops ◽

On Farm

Abstract Northern Italy is an area particularly suitable for the cultivation of different crops. It used to be characterized by a high agrobiodiversity. However, it is estimated that over the last decades, this area experienced a genetic erosion of more than 95%, resulting in the loss of many traditional plant genetic resources (PGR). Nevertheless, recent surveys found an unexpectedly high agrobiodiversity which remains. The presented study aims to provide a complete overview of plant agrobiodiversity (in terms of crop landraces, old cultivars and neglected crops) in northern Italy using a mixed approach of literature research and ethnobotanical field surveys. This paper is a fundamental step towards putting in place successful on farm and ex situ conservation measures in the study area. 811 entities were found, of which 27 were identified as neglected crops, 377 as landraces (plus 124 doubtful landraces) and 99 as old cultivars (plus 184 doubtful old cultivars). 248 entities were here recorded for the first time through field surveys. It clearly emerges that by using an ethnobotanical approach, several PGR can still be found in the study area especially in small farms and home gardens. We describe hotspots of crop diversity and areas in which there is still a lack of knowledge of local agrobiodiversity. Only 43% of the PGR recorded are conserved long-term in seed banks, underlying the fact that great efforts are needed to ensure the ex situ conservation of PGR in northern Italy. Careful interventions are needed to enhance the on-farm conservation status of the crop diversity reported here by enhancing its demand and its accessibility.

Download Full-text