A xyloglucan-induced increase in lettuce germination and seedling elongation is not related to the degradation of the exogenous xyloglucan

作者：Pereira Netto Adaucto B^*; Petkowicz Carmen L O

来源：Botany, 2013, 91(12): 822-829.

DOI：10.1139/cjb-2013-0099

• cell wall expansion
• HPSEC
• Hymenaea courbaril
• Lactuca sativa

Xyloglucans are the main hemicellulosic polysaccharides found in the primary cell walls of dicots and nongraminaceous monocots. Although xyloglucans are building blocks used in plant cell wall assembly, the function of these molecules in the structure and growth of the primary cell wall remains poorly understood. In this study, we demonstrate that treatment of lettuce seeds with a xyloglucan extracted from cotyledons of Hymenaea courbaril L. (Leguminosae (Fabaceae) - Caesalpinioideae) in the 0.1 to 10 nmol.L-1 range resulted in significantly increased germination percentage. In addition, lettuce seedlings grown in the presence of 500 nmol.L-1 xyloglucan presented a significantly larger length compared with seedlings grown in the absence of xyloglucan. Furthermore, the H. courbaril xyloglucan was not able to reverse a 2,4-dichlorophenoxy acetic acid induced inhibition of seedling elongation. High performance size exclusion chromatography (HPSEC) and high-performance liquid chromatography (HPLC) analyses indicated that the xyloglucan-induced enhancement of germination percentage and seedling elongation in lettuce does not rely on the release of monomers, i.e., glucose, xylose, and galactose from the exogenous xyloglucan.

• 出版日期2013-12