Genetic analysis of a heritage variety collection

Abstract

Landraces (including heritage varieties) are an important agrobiodiversity resource offering considerable value as a buffer against crop failures, as a crop for niche markets, and as a source of diversity for crop genetic improvement activities underpinning future food security. Home gardens are reservoirs of landrace diversity, but some of the accessions held in them are vulnerable or threatened with extinction. Those associated with seed saving networks have added security, for example, ca. 800 varieties are stored in the Heritage Seed Library (HSL) of Garden Organic, UK. In this study, Amplified Fragment Length Polymorphisms-based genetic analysis of accessions held in the HSL was used to (a) demonstrate the range of diversity in the collection, (b) characterize accessions to aid collection management and (c) promote broader use of the collection. In total, 171 accessions were included from six crops: Vicia faba L., Pisum sativum L., Daucus carota L., Cucumis sativus L., Lactuca sativa L. and Brassica oleracea L. var. acephala (DC.) Metzq. Average expected heterozygosity ranged from 0.18 to 0.28 in D. carota; 0.02–0.18 in P. sativum; 0.05–0.18 in L. sativa; 0.15–0.26 in B. oleracea var. acephala; 0.15–0.37 in C. sativus and 0.07–0.36 in V. faba. Genetic diversity and Fst values generally reflected the breeding system and cultivation history of the different crops. Comparisons of the diversity found in heritage varieties with that found in commercial varieties did not show a consistent pattern. Principal coordinates analysis and Unweighted Pair Group Method with Arithmetic Mean cluster analysis were used to identify four potential duplicate accession pairs.

Pursuing the Potential of Heirloom Cultivars to Improve Adaptation, Nutritional, and Culinary Features of Food Crops

“…acephala (DC.)) accessions, as well as 3.6-to 9-fold differences within faba bean, pea, and lettuce accessions [33]. Heirloom beans from southern Italy exhibited significant diversity in seed shape (cuboid, kidney, oval, round, truncate), seed coat pattern (absent, bicolor, pattern around hilum, speckled, spotted bicolor, stripped), seed color (black, brown, grey, vine, violet, white), seed weight (21-74 g 100 seed), and phaseolin (C, T, S) [78].…”

“…acephala (DC.) Metzq, faba bean (Vicia faba L.), pea (Pisum sativum L.), and lettuce (Lactuca sativa L.) [33]. Table 1 presents a list of a few websites providing further information on gene banks or seed-savers for heirloom cultivars.…”

Community Seed Groups: Biological and Especially Social Investigations Can Support Crisis Response Capacity

“…There is evidence that home or community gardens can be reservoirs of diversity not otherwise available. For example, a study in England that reviewed genetic diversity of 171 heritage varieties of six vegetable species maintained by a home gardeners' seed network found those varieties to contain "a unique and broad spectrum of crop genetic diversity… not represented in more formal genebanks" (Preston et al 2019).…”

Pursuing the potential of heirloom cultivars to improve adaptation, nutritional and culinary features in a changing climate

“…example, AFLP analysis of 171 heirlooms from the Heritage Seed Library (HSL) of Garden Organic revealed 1.5 to 2-fold differences in heterozygosity within carrot, cucumber and Brassica accessions, as well as 3.6 to 9-fold differences within faba bean, pea, and lettuce accessions[31].Heirloom beans from southern Italy exhibited significant diversity in seed shape (cuboid, kidney, oval, round, truncate), seed coat pattern (absent, bicolor, pattern around hilum, speckled, spotted bicolor, stripped), seed color (black, brown, grey, vine, violet, white), seed weight (21-74 g 100 seed), and phaseolin (C, T, S)[76]. 'Badda', a round large-seeded bean with a partially coloured seed coat, has been in cultivation for more than two centuries by Sicilian farmers.…”