Volatile organic compounds (VOCs) released from bacterial species have been reported as plant growth inducers. In this sense, Lactuca sativa was used as model vegetable to prospect the effects of 2-nonanone released by Bacillus sp. BCT9 at cellular and organ structure level, so we present preliminary results about the physiological effects. In this study, 2-day-old L. sativa were exposed to 2-nonanone for 10 days under two delivery systems: 1) 2-nonanone (abrupt delivery) and 2) 2-nonanone + lanolin (controlled delivery). The X-ray elemental microanalysis, scanning electron and confocal laser microscopies techniques were used to evaluate physiological changes “in vivo” conditions. The results indicated that 2-nonanone increased root and shoot length independently of 2-nonanone delivery system after 7 days of exposition. Additionally, 2-nonanone elicited the increase of anthocyanin and not affects chlorophyll content and electrolyte leakage percentage. The abrupt delivery elicited the increase of both length and density of root hair without causing changes in size of cell epidermis, while controlled delivery induced stomatal opening. Besides, 2-nonanone exposition did not modify the composition and distribution of carbon, nitrogen, phosphorus, potassium, and chlorine in the surface of plant tissue. The results suggested that 2-nonanone acts as a bacterial signal molecule to elicit changes related to root development without damaging the external morphology while epidermal cells at leaf level are not affected, suggesting that 2-nonanone can be an important tool to apply to vegetables.

从细菌物种释放的挥发性有机化合物（VOC）已被报道为植物生长诱导剂。从这个意义上说，紫花苜蓿被用作模型蔬菜，以研究芽孢杆菌属（Bacillus sp。）释放的2-壬酮的作用。BCT9在细胞和器官结构水平上，因此我们提供了有关生理效应的初步结果。在这项研究中，2天大的L. sativa在两种递送系统下，将其暴露于2-壬酮10天：1）2-壬酮（突然递送）和2）2-壬酮+羊毛脂（受控递送）。X射线元素显微分析，扫描电子和共聚焦激光显微技术被用于评估“体内”条件下的生理变化。结果表明，暴露2天后2-壬酮能独立于2-壬酮传递系统而增加根和茎长。另外，2-壬酮引起花色苷的增加，并且不影响叶绿素含量和电解质渗漏百分比。突然的输送引起根毛的长度和密度的增加，而不会引起细胞表皮大小的改变，而受控的输送引起气孔开放。除了，2-壬酮暴露不会改变植物组织表面碳，氮，磷，钾和氯的组成和分布。结果表明2-壬酮是一种细菌信号分子，可引起与根发育相关的变化，而不会损害外部形态，而叶面的表皮细胞不受影响，表明2-壬酮可能是应用于蔬菜的重要工具。