Gfeller Aurélie, Glauser Gaétan, Etter Clément, Signarbieux Constant, Wirth Judith
Herbology in Field Crops and Viticulture, Plant Production Systems, Agroscope, Nyon, Switzerland.
Neuchâtel Platform of Analytical Chemistry, University of Neuchâtel, Neuchâtel, Switzerland.
Front Plant Sci. 2018 Jan 31;9:50. doi: 10.3389/fpls.2018.00050. eCollection 2018.
Weed control by crops through growth suppressive root exudates is a promising alternative to herbicides. Buckwheat () is known for its weed suppression and redroot pigweed () control is probably partly due to allelopathic root exudates. This work studies whether other weeds are also suppressed by buckwheat and if the presence of weeds is necessary to induce growth repression. Buckwheat and different weeds were co-cultivated in soil, separating roots by a mesh allowing to study effects due to diffusion. Buckwheat suppressed growth of pigweed, goosefoot and barnyard grass by 53, 42, and 77% respectively without physical root interactions, probably through allelopathic compounds. Root exudates were obtained from sand cultures of buckwheat (BK), pigweed (P), and a buckwheat/pigweed mixed culture (BK-P). BK-P root exudates inhibited pigweed root growth by 49%. Characterization of root exudates by UHPLC-HRMS and principal component analysis revealed that BK and BK-P had a different metabolic profile suggesting that buckwheat changes its root exudation in the presence of pigweed indicating heterospecific recognition. Among the 15 different markers, which were more abundant in BK-P, tryptophan was identified and four others were tentatively identified. Our findings might contribute to the selection of crops with weed suppressive effects.
作物通过生长抑制性根系分泌物进行杂草控制是一种很有前景的除草剂替代方法。荞麦（）以其抑制杂草的特性而闻名，对反枝苋（）的控制可能部分归因于化感根系分泌物。这项研究旨在探讨荞麦是否也能抑制其他杂草，以及杂草的存在是否是诱导生长抑制所必需的。将荞麦和不同的杂草在土壤中共培养，用网隔开根系，以便研究扩散作用产生的影响。在没有根系物理相互作用的情况下，荞麦分别抑制了反枝苋、藜和稗草的生长，抑制率分别为53%、42%和77%，这可能是通过化感化合物实现的。从荞麦（BK）、反枝苋（P）以及荞麦/反枝苋混合培养物（BK-P）的砂培中获取根系分泌物。BK-P根系分泌物抑制反枝苋根系生长达49%。通过超高效液相色谱-高分辨质谱（UHPLC-HRMS）和主成分分析对根系分泌物进行表征，结果表明BK和BK-P具有不同的代谢谱，这表明荞麦在有反枝苋存在时会改变其根系分泌物，表明存在异源特异性识别。在BK-P中含量更高的15种不同标志物中，鉴定出了色氨酸，并初步鉴定出了其他4种。我们的研究结果可能有助于筛选具有杂草抑制作用的作物。
