RECQ4 restricts non-interfering crossover formation to fine-tune meiotic recombination rates in rice.

Crop breeding fundamentally depends on meiotic crossovers (COs) to reshuffle genetic material and integrate favourable alleles into elite cultivars. Recombination frequency is of paramount importance in this process. Higher recombination rates enhance the probability of breaking linkage drag and generating novel allelic combinations. Here, using rice (Oryza sativa) as a model crop species, we reveal that RECQ4, a conserved suppressor of meiotic CO formation, is indispensable for safeguarding the integrity of meiotic recombination intermediate metabolism. We demonstrate that RECQ4 limits COs in rice by specifically suppressing non-interfering CO pathways. Genetic redundancy with FANCM underscores their cooperative function in ensuring canonical CO formation, which is essential for accurate homologue segregation and genome stability. Furthermore, the recq4 dmc1 double mutant exhibits persistent chromosome fragmentation, implicating RECQ4 in resolving recombination intermediates through sister chromatid repair. Our findings redefine RECQ4's role in crop meiosis, bridging its CO suppression activity with broader genome surveillance functions.