Impairment of the sieve tube sealing mechanism of trees infected by mycoplasma-like organisms
1989
Kollar, A. (Biologische Bundesanstalt fuer Land- und Forstwirtschaft, Dossenheim (Germany, F.R.). Inst. fuer Pflanzenschutz im Obstbau) | Seemueller, E. | Krczal, G.
Apple (Malus pumila Mill.), alder (Alnus glutinosa (L.) Gaertn.), and aspen (Populus tremula L.) belong to the tree species which do not exudate if the phloem is severed. On proliferation-diseased apple trees as well as on alder and aspen tree similarly infected by mycoplasma-like organisms (MLOs) it was observed that at a variable number of trees the sealing mechanism of the sieve tubes was affected. From such trees up to 10 ml exudate were obtained. On apple, exudation was significantly influenced by the cultivar. Histological studies revealed that exudation is closely related to MLP colonization at the site of incision. MLOs were always found in the sieve tube sap at a concentration of at least 2400 organisms per ml
显示更多 [+] 显示较少 [-]