Yanniccari Marcos, Vázquez-García José G, Gómez-Lobato María E, Rojano-Delgado Antonia M, Alves Pedro L da C A, De Prado Rafael
National Scientific and Technical Research Council, Buenos Aires, Argentina.
Chacra Experimental Integrada Barrow, MDA-INTA, Tres Arroyos, Argentina.
Front Plant Sci. 2021 Feb 18;12:617945. doi: 10.3389/fpls.2021.617945. eCollection 2021.
Vahl. has been used as a valuable forage crop, but it has also been noted as a weed of winter crops and an invader in several countries. In Argentina, a putative glyphosate-resistant population of was identified as a consequence of the lack of effective control with glyphosate in the pre-sowing of wheat. Plant survival and shikimate accumulation analysis demonstrated a lower glyphosate-sensitivity of this population in comparison to a susceptible population. The resistant population was 4-fold more resistant to glyphosate than its susceptible counterpart. There was no evidence of target-site mechanisms of glyphosate resistance or an enhanced capacity to metabolize glyphosate in the resistant population. However, the resistant plants showed a lower foliar retention of glyphosate (138.34 μl solution g dry weight vs. 390.79 μl solution g dry weight), a reduced absorption of C-glyphosate (54.18 vs. 73.56%) and lower translocation of C-glyphosate from the labeled leaf (27.70 vs. 62.36%). As a result, susceptible plants accumulated a 4.1-fold higher concentration of C-glyphosate in the roots compared to resistant plants. The current work describes the first worldwide case of glyphosate resistance in . A reduced foliar retention of herbicide, a differential rate of glyphosate entry into leaves and an altered glyphosate translocation pattern would be the most likely mechanisms of glyphosate exclusion.
法尔（Vahl.）一直被用作一种有价值的饲料作物，但它也被视为冬季作物的杂草以及在多个国家的入侵物种。在阿根廷，由于小麦播种前使用草甘膦未能有效控制，发现了一个疑似对草甘膦具有抗性的法尔种群。植株存活和莽草酸积累分析表明，与敏感的法尔种群相比，该种群对草甘膦的敏感性较低。抗性种群对草甘膦的抗性是其敏感对应种群的4倍。没有证据表明抗性种群存在草甘膦抗性的靶标位点机制或增强的草甘膦代谢能力。然而，抗性植株的草甘膦叶面滞留量较低（138.34微升溶液/克干重，而敏感植株为390.79微升溶液/克干重），碳-草甘膦的吸收减少（54.18%对73.56%），且碳-草甘膦从标记叶片的转运较低（27.70%对62.36%）。结果，与抗性植株相比，敏感植株根部积累的碳-草甘膦浓度高4.1倍。当前研究描述了法尔在全球首例对草甘膦产生抗性的情况。除草剂叶面滞留量减少、草甘膦进入叶片的速率差异以及草甘膦转运模式改变可能是草甘膦排斥的最可能机制。
