欧亚国际

法国科学家利用Airphen多光谱相机发表了题为Tree architecture, light interception and water use related traits are controlled by different genomic regions in an apple tree core collection的文章，文章发表于知名期刊New Phytologist。

Tree architecture, light interception and water use related traits are controlled by different genomic regions in an apple tree core collection

Aude Coupel-Ledru,Benoît Pallas,Magalie Delalande,Vincent Segura,Baptiste Guitton,Hélène Muranty,Charles-Eric Durel,Jean-Luc Regnard,Evelyne Costes

SUMMARY

Tree architecture shows large genotypic variability, but how this affects water deficit responses is poorly understood. To assess the possibility of reaching ideotypes with adequate combinations of architectural and functional traits in the face of climate change, we combined high-throughput field phenotyping and genome-wide association studies (GWAS) on an apple tree (Malus domestica) core-collection.

We used T-LiDAR scanning and airborne multispectral and thermal imagery to monitor tree architecture, canopy shape, light interception, vegetation indices and transpiration on 241 apple cultivars submitted to progressive field soil drying. GWAS was performed with SNP-by-SNP and multi-SNP methods.

Large phenotypic and genetic variability was observed for all traits examined within the collection, especially canopy surface temperature in both well-watered and water deficit conditions, suggesting control of water loss was largely genotype-dependent. Robust genomic associations revealed independent genetic control for the architectural and functional traits. Screening associated genomic regions revealed candidate genes involved in relevant pathways for each trait.

We show that multiple allelic combinations exist for all studied traits within this collection. This opens promising avenues to jointly optimise tree architecture, light interception and water use in breeding strategies. Genotypes carrying favourable alleles depending on environmental scenarioses and production objectives could thus be targeted.

树结构、光截获和水分利用相关性状受苹果树核心种质中不同基因组区域的控制

总结

树木结构显示出很大的基因型变异性，但对水分亏缺反应的影响尚不清楚。在面对气候变化的情况下,充分利用结合和功能特征，评估达到理想型的可能性，我们在苹果树（Malus domestica）核心种质上结合了高通量田间表型分析和全基因组关联研究（GWAS）。

我们使用T-LiDAR扫描和机载多光谱和热成像技术，对241个苹果品种的树木结构、冠层形状、光截获、植被指数和蒸腾作用进行了监测，这些品种置于渐进式田间土壤干燥处理下。采用SNP和多SNP方法对SNP进行GWAS分析。

在采集的所有性状中，观察到很大的表型和遗传变异性，尤其是在水分充足和缺水条件下的冠层表面温度表型和遗传变异性，这表明水分流失的控制在很大程度上取决于基因型。强大的基因组关联揭示了结构和功能特征的独立遗传控制。筛选相关的基因组区域发现了参与每个性状相关途径的候选基因。

研究表明，在这个集合中，所有研究性状都存在多个等位基因组合，这为在育种策略中联合优化树木结构、光截获和水分利用开辟了有希望的途径。携带有利等位基因的基因型取决于环境情景，因此可以作为生产目标。