Genetic Diversity and Stability of Performance of Wheat Population Varieties Developed by Participatory Breeding

Gaëlle Van Frank,Sophie Pin,Hélène Montaz,Raphaël Baltassat,Isabelle Goldringer,Jean-Sébastien Gascuel,François Caizergues,Jean-François Berthellot,Bernard Ronot,Alexandre Hyacinthe,Pierre Rivière,Florent Mercier,Christian Dalmasso

doi:10.3390/su12010384

Abstract

Modern agricultural systems rely on reduced crop genetic diversity, due in particular to the use of homogeneous elite varieties grown in large areas. However, genetic diversity within fields is a lever for a more sustainable production, allowing greater stability and resistance to biotic and abiotic stresses. In France, a Participatory Plant Breeding (PPB) project on bread wheat, involving farmers, facilitators and researchers, has led to the development of heterogeneous populations whose within-variety genetic diversity is expected to confer the ability to adapt to farmers’ practices and environments. We studied the stability and local adaptation of ten of these farmers’ populations as well as two commercial varieties in relation to their within-variety genetic diversity. Although no clear evidence of local adaptation was detected, we found that populations’ grain yield and protein content were more stable over space and time respectively than those of commercial varieties. Moreover, the varieties’ stability over time in terms of protein content was positively correlated with within-variety genetic diversity with no significant drawback on protein yield. These results demonstrate the wide adaptive potential of PPB populations, highlighting the importance of seed exchange networks for agrobiodiversity management and use. They emphasize the benefits of genetic diversity for stability over time, which is of great interest to farmers.

Highlights

In recent decades, the increase in inter-annual climate variability has led to instabilities in agricultural production, sometimes leading to food shortages and rises in global food prices [1,2])
Projections predict an increase in frequency of extreme low yields due to adverse weather conditions [3,4], since current homogeneous varieties lack resilience to cope with climate instability as was demonstrated for European wheat varieties [5]
One of Savoysone’s parents (Blanc de Saône) is very close genetically to three of Mélange-5-Bourguignonnes’ landrace components (Blé de la Saône, Blanc hâtif de la Saône and Blanc de haute Saône), which may explain the genetic proximity of these two Participatory Plant Breeding (PPB) populations

Summary

Introduction

The increase in inter-annual climate variability has led to instabilities in agricultural production, sometimes leading to food shortages and rises in global food prices [1,2]). One of the identified levers is the increase of genetic diversity at the field level which allows for better disease regulation [11,12], greater resilience to climate variability [13,14,15], and better ecosystems functioning [16,17,18]. Increased within-field diversity can be achieved by growing landraces or old varieties (i.e., in the French context, varieties cultivated before 1940 and generally showing some intrinsic genetic variability), by mixing or crossing varieties, and by growing Composite Cross Populations (CPP) or open-pollinated varieties [19]. Overyielding and stability effects of variety mixtures were found to increase with components diversity [23,24]; no correlation was found with genome-wide genetic diversity for example in oat [25]

Methods

Results

Discussion

Conclusion