Thirty-five of 83 Pythium isolates from Indiana were identified as P. sylvaticum by the production of sexual reactions and mature oospores in matings with the male and female type cultures of that species. Revised and expanded taxonomic descriptions of P. sylvaticum are presented. P. sylvaticum appears to be synonymous with P. debaryanum var. pelargonii. All P. sylvaticum isolates could be placed in heterothallic male or female groups. Many isolates were also homothallic. The mating system of P. sylvaticum does not represent sexual dimorphism because some isolates of the male group produced heterothallic sexual reactions in paired matings. Variations in sexual reactions indicate that P. sylvaticum comprises male and female isolates which differ in sexual strength.
51 : 429-436. 1973. The sexuality and population structure of Sexual characteristics of 36 isolates of Pythi~~nz sylvatic~mz were investigated. Fourteen of 15 heterothallic males were also homothallic while only 2 of 21 females were homothallic. Four male and five female groups of isolates were delineated by similar reacting patterns under five different temperature and light conditions. Mature oospores formed in crosses varied with both male and female isolates and were not correlated with sexual strengths of reacting isolates. Three-to-one ratios of males to all other progeny occurred among 198 single-oospore progeny of two crosses involving non-homothallic parents. Most progeny were also homothallic. A pattern for the distribution of sexual characteristics of natural populations of P. sylvaticrun is proposed based on characteristics of the 36 isolates.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.