Response of tea plants (Camellia sinensis (L.) O. Kontze) to Al (300 μM AlCl3 for 14 weeks) was studied in combination with deficient (-B) or adequate B supply (?B) in hydroponics. Aluminum improved plant growth under B deficiency. This positive Al effect in (-B) plants was related to an Al-induced increase of B contents in the root cell walls (CW). Moreover, in (-B) plants more Al was partitioned into CW-bound fractions in both leaves and roots than in (+B) plants; an indication that B deficiency reduced the mobility of Al in the tea plants. In general, the highest activities of phenylalanine ammonia lyase, polyphenol oxidase, and soluble and CW-bound fractions of peroxidases were observed in (+Al/-B) plants. In (-B) plants Al supply caused a reduction of CW-bound phenolic acids and lignin, while the concentrations of soluble phenolics increased in the leaves. In the roots, however, Al treatment of B-deficient plants caused a significant increase of CW-bound phenolic acids, but not of lignin. Our results suggest that increased B partitioning into CW and reduction of lignification were important causes for Al-mediated amelioration of growth in B-deficient plants. In addition, the observation that in (+Al/-B) roots CW binding of both Al and phenolic acids was enhanced indicates that in the B-deficient roots Al was mainly bound to the CW phenolic acids; this, in turn, reduced their availability for enzymatic reactions and lignin synthesis.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.