Some Aspects of Morphology, Genetics, and Cultural Behavior of Gelasinospora Calospora Var. Autosteira
1958; Taylor & Francis; Volume: 50; Issue: 3 Linguagem: Inglês
10.1080/00275514.1958.12024731
ISSN1557-2536
Autores Tópico(s)Plant Disease Resistance and Genetics
ResumoThe organism used in this study, Gelasinospora calospora (Mouton) Moreau & Moreau var. autosteira (Alexopoulos & Sun) Alexopoulos & Sun, is a strictly heterothallic pyrenomycete closely allied to Neurospora and Fimetaria. Alexopoulos and Sun (1) gave this form varietal status so as to separate it from the strictly homothallic Gelasinospora calospora, which is practically indistinguishable on a morphological basis. When two isolates of opposite compatibility are mated on a suitable medium, dark, pyriform perithecia containing asci with eight uniseriately arranged ascospores are produced. From the cytological study of ascospore formation made by Sun, Alexopoulos, and Wilson (38) it is evident that this linear arrangement of the ascospores indicates the exact order of nuclear movement during meiosis. Therefore, just as in such organisms as Neurospora sitophila, N. crassa and Bombardia lunata, an analysis of the tetrads yields information about the segregation of alleles during meiosis (10, 11, 28, 44). Interest in Gelasinospora calospora var. autosteira was initiated when it was first described by Alexopoulos and Sun (1) in 1950. They removed the spores from two asci and found the compatibility factor segregated at first division. In addition, they found considerable variation in: 1) the intensity of the pigmentation of the mycelium, 2) the length of time required for the development of perithecia, 3) the relative numbers of perithecia produced in matings, 4) the distribution of perithecia in Petri-dish matings, and 5) the fertility of isolates after repeated subculture. Accordingly, this investigation was undertaken to determine to what extent the environmental culture conditions and genetic segregation con-
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