Change in XET activities, cell wall extensibility and hypocotyl elongation of soybean seedlings at low water potential

摘要: In dark-grown soybean (Glycine max [L.] Merr.) seedlings, exposing the roots to water-deficient vermiculite (ψw=−0.36 MPa) inhibited hypocotyl (stem) elongation. The inhibition was associated with decreased extensibility of cell walls in elongation zone. A detailed spatial analysis showed xyloglucan endotransglucosylase (XET; EC 2.4.1.207) activity on basis unit wall dry weight region after seedlings were transplanted low ψw. decrease XET at least partially due an accumulation mass. Since number only slightly altered, mass had increased per and probably led thickness extensibility. Alternatively, increase may represent a mechanism for regulating enzyme walls, this case, therefore Hypocotyl recovered grown low-ψw vermiculate about 80 h. partial recovery enhancement Our results indicate XTH proteins play important role thus hypocotyls. also imperfect correlation along Other potential functions their regulation growth are discussed.