Department of Ecology, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
Department of Biological Sciences, Eastern Illinois University, Charleston, Illinois, USA.
Plant Cell Environ. 2024 Dec;47(12):4572-4585. doi: 10.1111/pce.15055. Epub 2024 Jul 22.
The improvement of performance and yield in both cultivar and species mixtures has been well established. Despite the clear benefits of crop mixtures to agriculture, identifying the critical mechanisms behind performance increases are largely lacking. We experimentally demonstrated that the benefits of rice cultivar mixtures were linked to relatedness-mediated intraspecific neighbour recognition and discrimination under both field and controlled conditions. We then tested biochemical mechanisms of responses in incubation experiments involving the addition of root exudates and a root-secreted signal, (-)-loliolide, followed by transcriptome analysis. We found that closely related cultivar mixtures increased grain yields by modifying root behaviour and accelerating flowering over distantly related mixtures. Importantly, these responses were accompanied by altered concentration of signalling (-)-loliolide that affected rice transcriptome profiling, directly regulating root growth and flowering gene expression. These findings suggest that beneficial crop combinations may be generated a-priori by manipulating neighbour genetic relatedness in rice cultivar mixtures and that root-secreted (-)-loliolide functions as a key mediator of genetic relatedness interactions. The ability of relatedness discrimination to regulate rice flowering and yield raises an intriguing possibility to increase crop production.
已经充分证实，在品种和物种混合体中，性能和产量都得到了提高。尽管作物混合对农业有明显的好处，但对于提高性能背后的关键机制却知之甚少。我们通过实验证明，在田间和对照条件下，水稻品种混合的好处与种内亲缘关系介导的近邻识别和区分有关。然后，我们通过涉及添加根分泌物和根分泌信号（(-)-洛里奥利德）的孵育实验测试了生化反应机制，随后进行了转录组分析。我们发现，亲缘关系密切的品种混合物通过改变根系行为并加速与远缘混合物相比的开花，增加了籽粒产量。重要的是，这些反应伴随着信号（(-)-洛里奥利德）浓度的改变，这影响了水稻转录组谱，直接调节根系生长和开花基因表达。这些发现表明，可以通过在水稻品种混合物中操纵近邻遗传相关性来预先产生有益的作物组合，而根分泌的（-）-洛里奥利德作为遗传相关性相互作用的关键介质发挥作用。亲缘关系识别调节水稻开花和产量的能力提出了一个有趣的可能性，可以提高作物产量。
