Anomalies in Structure, Growth Characteristics, and Nutritional Composition as Induced by 2,4-Dichlorophenoxy Acetic Acid Drift Phytotoxicity in Grapevine Leaves and Clusters
Anomalies in Structure, Growth Characteristics, and Nutritional Composition as Induced by 2,4-Dichlorophenoxy Acetic Acid Drift Phytotoxicity in Grapevine Leaves and Clusters
复制标题
DOI：
10.21273/jashs.136.3.165
复制
发表时间：
2011-05-01
影响因子：
1.9
通讯作者：
Bondada, Bhaskar R.
中科院分区：
文献类型：
--
作者：
Bondada, Bhaskar R.
自 2,4-二氯苯氧基乙酸 (2,4-D) 喷雾漂移在 2,4-二氯苯氧基乙酸 (2,4-D) 于 20 世纪 40 年代发现以来，其漂移危害和喷雾漂移对多年生木本植物的影响已被普遍观察到；然而，2,4-D 诱导的植物毒性、形态发生以及营养和生殖结构的结构和组成异常尚不清楚。对来自经历持续漂移的商业葡萄园的健康和 2,4-D 损伤的葡萄树 (Vitis vinifera L.) 芽进行了比较。使用光学和扫描电子显微镜 (SEM) 检查健康和 2,4-D 损伤的叶子和浆果的形态解剖学。随着显微镜检查，气孔！还测定了电导 (g(S))、叶片生长特性和矿物质成分。健康叶子的形态解剖学类似于典型的被子植物叶子。相比之下，暴露于 2,4-D 植物毒性的芽表现出异位行为，并发育出奇形怪状的畸形叶子，这些叶子厚实、扇形、内陷，并且由于叶脉的吸引而导致叶脉间皱起。由于实质替代组织的形成，细胞结构（包括维管束）发生了改变。 2,4-D 损伤叶片的 g(S)、叶指数、叶面积和叶柄尺寸显着减小。 2,4-D-受伤的叶子；然而，与健康叶子相比，它们积累了高水平的氮、钾和铁。受伤枝条的簇（受精花序）形成了上曲率，并且主要长出活的绿色子房（无籽未成熟的假果实），而不是真正的浆果（受精的完全成熟的肉质果实）。这些异常预计将严重扰乱光合作用和蒸腾作用的重要功能，低 g(S) 和坐果不良会导致衰老和局部坏死，最终导致当季芽死亡。
Drift hazards and the effects of 2,4-dichlorophenoxy acetic acid (2,4-D) spray drift on woody perennials have been commonly observed since its discovery in the 1940s; however, 2,4-D-induced phytotoxicity, morphogenesis, and structural and compositional anomalies of their vegetative and reproductive structures are not well understood. Healthy and 2,4-D-injured shoots of grapevine (Vitis vinifera L.) from a commercial vineyard experiencing persistent drift were compared. The morphoanatomy of healthy and 2,4-D-injured leaves and berries were examined using light and scanning electron microscopy (SEM). Along with the microscopic examinations, stomata! conductance (g(S)), leaf growth characteristics, and mineral composition were also determined. The morphoanatomy of healthy leaves resembled that of a typical angiospermic leaf. By contrast, shoots exposed to 2,4-D phytotoxicity displayed epinastic behavior and developed grotesquely malformed leaves that were thick, fan-shaped, enated, and interveinally puckered as a result of fasciation of veins. The cellular architecture, including the vascular bundles, was altered as a result of the formation of parenchymatous replacement tissues. The g(S), leaf index, leaf area, and petiole dimensions were significantly reduced in the 2,4-D-injured leaves. 2,4-D-injured leaves; however, accumulated high levels of nitrogen, potassium, and iron compared with healthy leaves. The clusters (fertilized inflorescences) of the injured shoots developed epinastic curvature and predominantly bore live green ovaries (seedless unripened pseudofruit) instead of true berries (fertilized fully ripened fleshy fruit). These abnormalities are expected to severely perturb the vital functions of photosynthesis and transpiration as evidenced by low g(S) and poor fruit set leading to senescence and localized necrosis ultimately causing death of current-season shoots.