Cope Jonathan E, Berckx Fede, Galinski Anna, Lentz Jonas, Nagel Kerstin A, Fiorani Fabio, Weih Martin
Department of Crop Production Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Institute of Bio- and Geosciences, Plant Sciences (IBG-2), Forschungszentrum Jülich GmbH, Jülich, Germany.
Front Plant Sci. 2024 Jun 4;15:1389593. doi: 10.3389/fpls.2024.1389593. eCollection 2024.
Root system architecture (RSA) plays an important role in the plant's ability to sustain yield under abiotic stresses such as drought. Preceding crops (precrops) can affect the yield of the proceeding crop, partially by affecting the RSA. This experiment aims to explore the interactions between precrop identity, crop genotype and drought at early growth stages.
Rhizotrons, sized 60 × 80 × 3.5 cm, were used to assess the early root growth of two winter wheat (Triticum aestivum L.) genotypes, using precrop-treated soil around the seedlings and differing water regimes. The rhizotrons were automatically imaged 3 times a week to track root development.
Precrop-treated soil affected the RSA and changes caused by the reduced water treatment (RWT) were different depending on the precrop. Largest of these was the 36% reduction in root depth after wheat, but 44% after OSR. This indicates that effects caused by the precrop can be simulated, at least partially, by transferring precrop-treated soils to controlled environments. The genotypes had differential RSA and reacted differently to the RWT, with Julius maintaining an 8.8-13.1% deeper root system compared to Brons in the RWT. In addition, the combined environmental treatment affected the genotypes differently.
Our results could help explain discrepancies found from using precrops to enhance yield as they indicate differences in the preceding crop effect when experiencing drought stress. Further, these differences are affected by genotypic interactions, which can be used to select and adapt crop genotypes for specific crop rotations, depending on the year. Additionally, we have shown a viable method of stimulating a partial precrop effect at the seedling stage in a controlled greenhouse setting using field soil around the germinated seed.
根系结构（RSA）在植物抵御干旱等非生物胁迫并维持产量的能力中起着重要作用。前茬作物会部分地通过影响根系结构来影响后续作物的产量。本试验旨在探究前茬作物种类、作物基因型与干旱在作物生长早期阶段的相互作用。
使用尺寸为60×80×3.5厘米的根箱，利用幼苗周围经过前茬作物处理的土壤和不同的水分状况，评估两种冬小麦（普通小麦）基因型的早期根系生长。每周对根箱自动成像3次以追踪根系发育情况。
经过前茬作物处理的土壤影响了根系结构，水分减少处理（RWT）所引起的变化因前茬作物而异。其中最大的差异是，前茬为小麦后根深度减少36%，而前茬为油菜籽后根深度减少44%。这表明，至少部分地，通过将经过前茬作物处理的土壤转移到可控环境中，可以模拟前茬作物所产生的影响。不同基因型具有不同的根系结构，并且对水分减少处理的反应也不同，在水分减少处理中，“朱利叶斯”基因型的根系深度比“布伦斯”基因型深8.8 - 13.1%。此外，综合环境处理对不同基因型的影响也不同。
我们的结果有助于解释在前茬作物用于提高产量时所发现的差异，因为它们表明了在遭受干旱胁迫时前茬作物效应的差异。此外，这些差异受基因型相互作用的影响，这可用于根据年份选择和适配特定轮作方式的作物基因型。此外，我们展示了一种在可控温室环境中，利用发芽种子周围的田间土壤在幼苗期模拟部分前茬作物效应的可行方法。
