Is the immune system required to adapt to flowering time change?

为了有效地改良作物，育种者必须能够在不影响产量的情况下选择相关的表型性状。该项目建议调查开花时间改变对植物育种的第二个主要性状的进化后果：免疫力。这将对理解开花时间和防御网络之间的相互作用以及开发有效的育种策略都有意义。有明确的证据表明，植物成熟度影响防御水平和有效性。理论模型实际上预测，生活史的变化可以调节免疫的成本和收益之间的平衡。同时，免疫系统的参与者经常被观察到改变开花时间。两种替代的和可能互补的假说可以解释这种联系：由于两个系统中的参与者的多效性作用而造成的遗传限制，或者如果开花时间的变化调节免疫的成本-收益平衡，则是共同进化。我们将使用构建的品系以及重组自交系和天然材料在拟南芥中进行田间测试，以区分这两个解释性假设的作用。利用转录组分析，我们将发现与开花时间改变相关的防御基因(f-t-a防御基因)。我们将在化验过程中对它们的表达进行量化，并测试它是否会随着开花时间和适合度的变化而变化。我们将进一步测试开花时间和免疫力是否相互作用，以决定番茄和马铃薯的产量。

For effective crop improvement, breeders must be able to select on relevant phenotypic traits without compromising yield. This project proposes to investigate the evolutionary consequences of flowering time modifications on a second trait of major importance for plant breeding: immunity. This will have implications both for understanding cross-talks between flowering time and defense network and for developing efficient breeding strategies.There is clear evidence that plant maturity influences levels and effectiveness of defense. Theoretical models actually predict that changes in life-history can modulate the balance between costs and benefits of immunity. Simultaneously, actors of the immune system have often been observed to alter flowering time.Two alternative and possibly complementary hypotheses can explain this link: genetic constraints due to the pleiotropic action of players in either systems, or co-evolution, if flowering-time changes modulate the cost-benefit balance of immunity. We will conduct field assays in Arabidopsis thaliana, using constructed lines as well as recombinant inbred lines and natural accessions, to differentiate the action of the two explanatory hypotheses. Using transcriptome analyses, we will identify defense genes associating with flowering time modification (f-t-a defense genes). We will quantify their expression along the assay and test whether it varies with both flowering time and fitness. We will further test whether flowering time and immunity interact to determine yield in tomato and potato.