Effects of the fungal hyperparasite Colletotrichumgloeosporioides of dwarf mistletoe (Arceuthobiumamericanum) on young lodgepole pine

John A. Muir
1977 Canadian Journal of Forest Research  
MUIR, J. A. 1977. Effects of the fungal hyperparasite Colletotriehum gloeosporioides of dwarf mistletoe (Areeuthobiw/l amerieal1um) on young lodgepole pine. Can. J. For. Res. 7: 579-583. Dwarf mistletoe (Areelllhobium amerieal1um Nutt. ex. Engelm.) infected by the fungus Colletotriehum gloeosporioides Penz. sensu von Arx was examined in two areas of young lodge pole pine (Pinus eontorta Doug\. var. lati/olia Engelm.) in southwestern Alberta. The fungus infected 35% and 75% of the dwarf
more » ... the dwarf mistletoe plants, 6% and 54% of the aerial shoots, and 7% and 8% of the berries in the respective areas. The number of dwarf mistletoe berries and maximum shoot lengths of dwarf mistletoe plants were significantly reduced by the fungus, and dead plants were more frequent than in areas where the fungus was absent. However, numbers of new dwarf mistletoe plants were not significantly reduced by the fungus. Evidently future increase in numbers of dwarf mistletoe plants and eventual damage to young lodgepole pine in the areas will not be significantly decreased by the fungus. MUIR, J. A. 1977. Effects of the fungal hyperparasite Colletotricllllm gloeosporioides of dwarf mistletoe (Areeuthobium amerieanum) on young lodgepole pine. Can. J. For. Res. 7: 579-583. L'infection du faux-gui, Areeuthobium amerieal1um Nutt. ex Engelm., par Ie champignon Colletotriehum gloeosporioides Penz. sensll von Arx a ete examinee dans deux regions peuplees de pin tordu (Pinus eontorta Doug\. var. lati/olia Engelm.) it l'etat juvenile dans Ie sud-ouest de l'Alberta. Le champignon infectait respectivement 35% et 75% des plants, 6% et 54% des pousses aeriennes et 7% et 8% des baies du faux-gui dans l'une et I'autre region. La reduction du nombre des baies et de la longueur maximum des pousses de faux-gui y etait significative, de meme que la frequences des plants morts y etait plus grande que dans les regions ou Ie champignon etait absent. Pourtant Ie nombre des plants nouveaux du faux-gui n'etait pas reduit de maniere significative par Ie champignon. Evidemment l'accroissement futur du faux gui et I'endommagement eventuel des jeunes sujets de pin tordu dans les regions etudiees ne seront pas reduits significativement par Ie champignon.
doi:10.1139/x77-075 fatcat:ugdrgylcsfcyrdygtiyozogqsy