Yanling Guoa, Moran Guo, Wenlu Zhao, Kaoshan Chen, Pengying Zhang*

Carbohydrate Polymers 97 (2013) 731–735

ABSTRACT

Burdock fructooligosaccharide (BFO) isolated from the root tissue of Arctium lappa is a reserve carbohy-drate that can induce resistance against a number of plant diseases. Stomatal closure is a part of plantinnate immune response to restrict bacterial invasion. In this study, the effects of BFO on stomata move-ment in Pisum sativum and the possible mechanisms were studied with abscisic acid (ABA) as a positivecontrol. The results showed that BFO could induce stomatal closure accompanied by ROS and NO produc-tion, as is the case with ABA. BFO-induced stomatal closure was inhibited by pre-treatment with l-NAME(NG-nitro-l-arginine methyl ester, hydrochloride; nitric oxide synthase inhibitor) and catalase (hydrogenperoxide scavenger). Exogenous catalase completely restricted BFO-induced production of ROS and NO inguard cells. In contrast, l-NAME prevented the rise in NO levels but only partially restricted the ROS pro-duction. These results indicate that BFO-induced stomatal closure is mediated by ROS and ROS-dependentNO production.