Table_7_Comparative Aerial and Ground Based High Throughput Phenotyping for the Genetic Dissection of NDVI as a Proxy for Drought Adaptive Traits in Durum Wheat.XLSX

High-throughput phenotyping platforms (HTPPs) provide novel opportunities to more effectively dissect the genetic basis of drought-adaptive traits. This genome-wide association study (GWAS) compares the results obtained with two Unmanned Aerial Vehicles (UAVs) and a ground-based platform used to measure Normalized Difference Vegetation Index (NDVI) in a panel of 248 elite durum wheat (Triticum turgidum L. ssp. durum Desf.) accessions at different growth stages and water regimes. Our results suggest increased ability of aerial over ground-based platforms to detect quantitative trait loci (QTL) for NDVI, particularly under terminal drought stress, with 22 and 16 single QTLs detected, respectively, and accounting for 89.6 vs. 64.7% phenotypic variance based on multiple QTL models. Additionally, the durum panel was investigated for leaf chlorophyll content (SPAD), leaf rolling and dry biomass under terminal drought stress. In total, 46 significant QTLs affected NDVI across platforms, 22 of which showed concomitant effects on leaf greenness, 2 on leaf rolling and 10 on biomass. Among 9 QTL hotspots on chromosomes 1A, 1B, 2B, 4B, 5B, 6B, and 7B that influenced NDVI and other drought-adaptive traits, 8 showed per se effects unrelated to phenology.

高通量表型平台（High-throughput phenotyping platforms, HTPPs）为更高效解析干旱适应性性状的遗传基础提供了全新机遇。本研究通过全基因组关联分析（GWAS），以248份优良硬粒小麦（*Triticum turgidum* L. ssp. *durum* Desf.）种质群体为材料，对比了2架无人机（Unmanned Aerial Vehicles, UAVs）与1套地面表型平台在不同生育阶段、不同水分条件下测定归一化差异植被指数（Normalized Difference Vegetation Index, NDVI）的结果。研究结果表明，相较于地面平台，空中表型平台检测NDVI相关数量性状基因座（quantitative trait loci, QTL）的能力更优，尤其在生育后期干旱胁迫条件下：前者共检测到22个单QTL，后者为16个；基于多重QTL模型计算的表型变异解释率分别为89.6%与64.7%。此外，本研究还针对该硬粒小麦种质群体在生育后期干旱胁迫下的叶片叶绿素含量（SPAD）、叶片卷曲度及干生物量开展了测定与分析。最终共鉴定到46个可在各表型平台中影响NDVI的显著QTL，其中22个同时对叶片绿度存在调控效应，2个影响叶片卷曲度，10个与生物量性状相关。在1A、1B、2B、4B、5B、6B及7B染色体上，共存在9个同时调控NDVI与其他干旱适应性性状的QTL热点区域，其中8个的遗传效应独立于物候期影响。