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生长，但由于上层土壤覆盖层和/或喷杆或枪式灌溉损坏了垄，可能会导致坚固的土壤。此外，由于（历史）犁盘（低于苗床准备深度）和土壤干燥（增加土壤强度），土壤强度（评估为土壤容重计阻力）随土壤深度垂直增加，这限制了根系生长。虽然马铃薯传统上被认为是浅根的，但选择能够在坚固土壤中生长的品种可以获得深层土壤水分，维持冠层发育和光合作用，并在块茎膨胀期间延迟冠层衰老。尽管马铃薯根系发育存在相当大的遗传变异（Wishart et al. 2013），并且已经在谷物中鉴定出了赋予穿透坚固土层的能力增加的根系性状（沃利et al. 2013），但尚不确定是否可以利用马铃薯根系对坚固土壤的响应中的遗传变异。 个别马铃薯植物将在不同水分含量和强度的土壤中生根，并且不确定植物如何响应这种空间异质环境来调节冠层生长。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，然而基底根（来自种薯）和匍匐茎衍生的根对该信号传导过程的贡献尚未被评估。因此，该项目的目的是确定：-基生根和匍匐茎根穿透坚固土壤的能力的遗传变异-这些根系对坚固土壤的根-冠信号的相对贡献-根据对坚固土壤的表型根系反应选择基因型是否可以提高田间种植作物的产量/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