Physoderma pulposum
- 1 January 1958
- Vol. 50 (1) , 80-84
- https://doi.org/10.2307/3756038
Abstract
P. pulposum was collected on Atriplex patula var. hastata in 1954-57, in the vicinity of Purdue University. Chenopodium album plants growing amidst the infected plants, however, were not infected by the fungus. Nevertheless, the fungus was found parasitizing only C. album plants 5 miles south of Lafayette, Indiana in 1956. The two collections of P. pulposum were continuously maintained on their respective hosts for over 2 years in the greenhouse by periodical inoculations with planospores derived from the epibiotic ephemeral zoosporangia. Cross infection reactiqns indicated that the 2 collections represented different formae speciales of P. pulposum. The life cycle of P. pulposum includes epibiotic zoosporangial phase and endobiotic rhizomycelioid resting sporangial phase. They incite characteristic and conspicuous galls on the host plants. The planospores from sporangia may function as zoospores, re-infect and develop into epibiotic sporangia, or may function as gametes and fuse. The zygotes infect the host and develop the rhizomycelia and the resting sporangia. The latter germinate by forming stellate opening. The epibiotic sporangia are also inoperculate. The resting sporangia of P. hemisphericum on Carum carvi, and a Physoderma sp. on Trifolium subterraneum from Australia, also germinate similarly. This indicates the existence of inoperculate species of Physoderma.This publication has 0 references indexed in Scilit: