Resistance detection of blackjack to ALS inhibitors by in vitro plant growth method

Abstract Background: The resistance of weeds to herbicides is a problem that has been increasingly studied because of its great importance in agriculture and rapid growth of this phenomenon worldwide. The quick detection of resistant plants is extremely important for resistance management. Weed resistance to herbicides can be detected through field, greenhouse and laboratory tests. A fast way of detecting resistance is using tissue culture method, where is possible to use resistant plant clones and obtain results faster than whole-plant method in greenhouse. Objective: The aims of the research were to detect the resistance of blackjack to herbicides inhibitors of the acetolactate synthase (ALS), addition in vitro cultivation; determine the herbicide concentration of imazethapyr to 95% control of the susceptible plant population; evaluate explants growth; and, determine the herbicide concentration added to the culture medium where is possible to distinguish a resistant from a susceptible plant. Methods: Experiments were carried out in greenhouse and tissue culture laboratory. Screening was performed to select resistant and susceptible biotypes, tests for specie establishment and dose response curves in vitro were made. Results: The herbicide concentration added to the culture medium that provided 95% susceptible biotype control and efficiently differentiated susceptible biotype from resistant one was 0.6μM of imazethapyr. Conclusions: This method helps recommendations of weed management and provides a quick decision to alternative control of this specie, thus avoiding major damage to the crops.

背景：杂草对除草剂的抗药性是当前农业领域备受关注的重要问题，且该现象在全球范围内快速扩散，相关研究需求日益增长。快速检测抗药性植株对于抗药性管理工作至关重要。目前可通过田间试验、温室试验与实验室试验三种途径检测杂草的除草剂抗药性。其中组织培养法是一种快速检测手段，可利用抗性植株克隆体，且相较于温室整株检测法，能够更快获得检测结果。
研究目的：本研究旨在通过体外培养法检测三叶鬼针草（blackjack）对乙酰乳酸合酶（acetolactate synthase, ALS）抑制剂类除草剂的抗药性；确定可使敏感种群达到95%防效的咪唑乙烟酸（imazethapyr）浓度；评估外植体生长情况；并明确可有效区分抗性与敏感植株的培养基除草剂添加浓度。
试验方法：本研究在温室与组织培养实验室开展试验。试验内容包括抗/敏感生物型筛选、物种建立试验，以及体外剂量反应曲线测定。
试验结果：可使敏感生物型达到95%防效、且可有效区分敏感与抗性生物型的培养基中咪唑乙烟酸添加浓度为0.6μM。
研究结论：该方法可为杂草管理方案制定提供参考，为该杂草的替代防治手段提供快速决策依据，从而避免作物遭受重大损失。