Exploiting genetic diversity in root phenotypes to overcome soil constraints to potato yields

尽管马铃薯种植者辛勤地准备苗床以促进作物的建立，但由于上层土层的覆盖和/或围栏或喷灌破坏了垄层，可能会产生坚硬的土壤。此外，土壤强度(评估为土壤渗透阻力)随着土壤深度的增加而垂直增加，这是由于(历史上的)犁盘(低于苗床准备深度)和土壤干燥(这增加了土壤强度)限制了根的生长。虽然马铃薯传统上被认为是浅根品种，但选择能在坚硬土壤中生长的品种可以获得深层土壤水分，维持块茎膨大期间的冠层发育和光合作用，延缓冠层衰老。尽管在马铃薯根发育中存在相当大的遗传变异(Wishart等人。2013年)，而且在谷物中已经确定了能够增强渗透坚硬土层的能力的根系特征(Whalley等人。2013)，还不确定是否可以利用马铃薯根系对坚硬土壤的反应的遗传变异。单个马铃薯植物将在不同水分含量和强度的土壤中扎根，目前还不确定植物如何对这种空间异质环境做出反应，以调节树冠的生长。干燥土壤中的根合成化学信号，这些信号被输送到地上部以调节冠层发育、光合作用和衰老，然而(来自种子马铃薯的)基根和匍匐茎来源的根对这一信号过程的贡献尚未得到评估。因此，该项目的目的是确定：-基根和地龙衍生的根穿透坚硬土壤的能力的遗传变异-这些根系对坚硬土壤的根冠信号的相对贡献-根据根型对坚硬土壤的反应来选择基因是否可以提高大田作物的产量/质量

Although potato growers assiduously prepare the seedbed to promote crop establishment, strong soil can result from the overburden of upper soil layers and/or boom or gun irrigation damaging the ridge. Furthermore, soil strength (assessed as soil penetrometer resistance) increases vertically with soil depth due to (historical) plough pans (below the depth of seedbed preparation) and soil drying (which increases soil strength), which limit root growth. Although potato is traditionally regarded as shallow rooted, selecting varieties better able to grow in strong soil can access soil moisture at depth, sustaining canopy development and photosynthesis and delaying canopy senescence during tuber bulking. Although considerable genetic variation in potato root development exists (Wishart et al. 2013), and root traits conferring increased ability to penetrate strong soil layers have been identified in cereals (Whalley et al. 2013), it is uncertain whether genetic variation in potato root response to strong soil can be exploited. Individual potato plants will have roots in soils of different moisture contents and strength, and it is uncertain how the plant responds to this spatially heterogeneous environment to regulate canopy growth. Roots in drying soil synthesise chemical signals which are transported to the shoot to regulate canopy development, photosynthesis and senescence, however the contribution of basal (from the seed potato) and stolon-derived roots to this signalling process has not been assessed. This seems critical in regulating crop performance, as these roots show different spatial occupation of the soil profile.Consequently, the project aims are to determine:- genetic variation in the ability of basal and stolon-derived roots to penetrate strong soil - the relative contribution of these root systems to root-to-shoot signalling of strong soil- whether selecting genotypes based on phenotyping root responses to strong soil can improve the yields / quality of field-grown crops