caa a22 4500 469097191 CHVBK 20180323133034.0 cr unu---uuuuu 170328e19920201xx s 000 0 eng 10.1007/BF00317231 doi (NATIONALLICENCE)springer-10.1007/BF00317231 Reduced mycorrhizae on Juniperus monosperma with mistletoe: the influence of environmental stress and tree gender on a plant parasite and a plant-fungal mutualism [Elektronische Daten] [Catherine Gehring, Thomas Whitham] Summary: We examined how an important plant mutualist (fungal mycorrhizae) interacted with a common tree parasite, a xylem-tapping mistletoe (Phoradendron juniperium Engelm.) growing on one-seeded juniper (Juniperus monosperma Engelm.). We also examined how host tree gender and environmental stress might be involved in this interaction. Four major patterns were observed. First, the mycorrhizal levels of trees of both sexes were negatively correlated with mistletoe density. In comparisons of heavily and lightly infested trees at the stressful site, high mistletoe levels were associated with 27% less mycorrhizae on male trees and 38% less mycorrhizae on the roots of female trees. Second, the reduction of mycorrhizae on trees with high mistletoe levels was slightly but significantly greater for female trees than male trees. These results are consistent with the hypothesis that severe mistletoe infestation suppresses mycoresis and that this suppression is more severe in female trees because of their greater energetic investment in reproduction. Third, female junipers growing in the stressful ash and cinder fields averaged three-fold higher levels of mistletoe infestation than male trees. Fourth, no differences in mistletoe infestation were observed between male and female trees growing in the more favorable soils. Comparisons with other systems suggest that both mistletoes and herbivores have similar interactions with mycorrhizae. Springer-Verlag, 1992 Dioecy nationallicence Environmental stress nationallicence Parasitic mistletoe nationallicence Mutualist nationallicence Mycorrhizal fungi nationallicence Gehring Catherine Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA aut Whitham Thomas Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA aut Oecologia Springer-Verlag 89/2(1992-02-01), 298-303 0029-8549 89:2<298 1992 89 442 https://doi.org/10.1007/BF00317231 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00317231 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gehring Catherine Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA aut NATIONALLICENCE 700 1- Whitham Thomas Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA aut NATIONALLICENCE 773 0- Oecologia Springer-Verlag 89/2(1992-02-01), 298-303 0029-8549 89:2<298 1992 89 442 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer