Chemical stress reduces the lateral shoot growth in vernalized garlic

ABSTRACT Brazil’s low garlic productivity is attributed, mainly to the lateral shoot growth, a physiological anomaly characterized by early lateral shoot growth of cloves in noble group garlic cultivars. Considering the aforementioned information, the aim was to evaluate the occurrence of lateral shoot growth and productivity characteristics in garlic plants, cv. Chonan, subject to herbicide chemical stress. In order to do so, an experiment was conducted in outlining randomized blocks in a 3x5 factorial scheme, constituted by three herbicides (paraquat 500 g ha-1; ammonium gluphosinate 400 g ha-1 and glyphosate 720 g ha-1) and five subdoses (0, 5, 10, 15 and 20% of the minimum recommended dose of each herbicide). The electron transport rates (ETR) were evaluated after herbicide application, as well as the culture’s morphological and productive characteristics. The chemical stress caused by herbicides paraquat, ammonium gluphosinate and glyphosate in underdoses of 25, 40 and 36 i.a. ha-1, respectively, was efficient in reducing the electron transport rate and the lateral shoot growth of the Chonan garlic cultivar, and also technically viable in increasing the productivity of commercial bulbs.

摘要 巴西大蒜单产偏低的核心诱因是侧芽生长异常，这是一类以优级大蒜品种群（noble group garlic cultivars）蒜瓣过早萌发侧芽为典型特征的生理紊乱现象。基于上述研究背景，本研究旨在评估除草剂化学胁迫下，朝南（Chonan）大蒜品种的侧芽发生情况与产量相关性状。为此，本研究采用3×5析因设计的随机区组方案开展试验，共设置3种除草剂（百草枯（paraquat）500 g·ha⁻¹、草铵膦（ammonium gluphosinate）400 g·ha⁻¹与草甘膦（glyphosate）720 g·ha⁻¹）以及5个亚剂量梯度（各除草剂最低推荐剂量的0、5、10、15、20%）。除草剂施用后，本研究对电子传递速率（electron transport rates, ETR）以及供试大蒜的形态与产量相关性状进行了测定。分别以25、40、36 g·ha⁻¹有效成分的亚剂量施用百草枯、草铵膦与草甘膦所产生的化学胁迫，可有效降低朝南大蒜品种的电子传递速率与侧芽生长量，且在技术层面可行，能够提升商品鳞茎的产量。