Résumé
Improved plant varieties are important in our attempts to face the challenges of a growing human population and limited planet resources. Plant breeding relies on meiotic crossovers to combine favourable alleles into elite varieties
1
. However, meiotic crossovers are relatively rare, typically one to three per chromosome
2
, limiting the efficiency of the breeding process and related activities such as genetic mapping. Several genes that limit meiotic recombination were identified in the model species
Arabidopsis thaliana
2
. Mutation of these genes in
Arabidopsis
induces a large increase in crossover frequency. However, it remained to be demonstrated whether crossovers could also be increased in crop species hybrids. We explored the effects of mutating the orthologues of
FANCM
3
,
RECQ4
4
or FIGL1
5
on recombination in three distant crop species, rice (
Oryza sativa
), pea (
Pisum sativum
) and tomato (
Solanum lycopersicum
). We found that the single
recq4
mutation increases crossovers about three-fold in these crops, suggesting that manipulating
RECQ4
may be a universal tool for increasing recombination in plants. Enhanced recombination could be used with other state-of-the-art technologies such as genomic selection, genome editing or speed breeding
6
to enhance the pace and efficiency of plant improvement.
The genes
FANCM
,
RECQ4
and
FIGL1
affect meiotic recombination in
Arabidopsis
. By examining the effects of their orthologues on recombination in three crop species, the authors find that mutating
RECQ4
could be a universal tool for increasing recombination.