Full text in pdf format

Ascospore number and viability in hybrid and selfed cleistothecia of Aspergillus nidulans

Neiva Monteiro de Barros^I; João Lúcio de Azevedo^II

^IInstituto de Biotecnologia, Universidade de Caxias do Sul, Caixa Postal 1352, 95070, Caxias do Sul, RS, Brasil
^IIInstituto de Genética, ESALQ/USP, Caixa Postal 83, 13400 Piracicaba, SP, Brasil. Send correspondence to J.L.A.

ABSTRACT

The aim of the present investigation was to study the number and viability of ascospores in hybrid and selfed cleistothecia of Aspergillus nidulans. Seven strains were crossed with each another in all possible combinations and the resulting cleistothecia were analyzed. A correlation was detected between cleistothecium diameter and ascospore number both for hybrid and selfed cleistothecia, whereas a correlation between cleistothecium diameter and number of viable ascospores was detected only in hybrids.

Keywords: ascospore; viability; hybrid; selfed; cleistothecia; Aspergillus nidulans.

REFERENCES

Baracho, I.R. (1968). Estudos sobre corpos de frutificação em Aspergillus nidulans. Masters Thesis. ESALQ, Piracicaba, 57 pp.

Baracho, I.R. and Azevedo, J.L. (1971). A quantitative analysis of cleistothecia production in Aspergillus nidulans. Experientia 27: 855-856.

Baracho, I.R. and Azevedo, J.A. (1977). Relative heterothallism in Aspergillus nidulans. Rev. Microbiol. 8:36-38.

Baracho, I.R., Vencovsky, E. and Azevedo, J.L. (1970). Correlation between size and hybrid or selfed state of the cleistothecia in Aspergillus nidulans. Trans. Br. Mycol. Soc. 54: 109-116.

Butcher, A.C. (1968). The relationship between sexual outcrossing and heterokaryon incompati- bility in Aspergillus nidulans. Heredity 23:443-452.

Caten, C.E. and Jinks, J.L. (1966). Heterokaryosis: its significance in wild homothallic ascomycetes and fungi inperfecti. Trans. Br. Mycol. Soc. 49: 81-93.

Clutterbuck, A.J. and Roper, J.A. (1966). A direct determination of nuclear distribution in heterokaryons of Aspergillus nidulans. Genet. Res. 7: 185-194.

De Lange, A.M. and Griffiths, A.F. (1980). Meiosis in Neurospora crassa. II. Genetic and cytological characterization of three meiotic mutants. Genetics 96: 379-398.

Hemmons, L.M., Pontecorvo, G. and Bufton, A.W.J. (1952). The technique of "perithecium analysis" in Aspergillus nidulans. Heredity 6: 135.

Mahoney, M. and Wilkie, D. (1958). An instance of cytoplasmic inheritance in Aspergillus nidulans. Proc. R. Soc. Lond. Soc. B 154:524-532.

Newmeyer, D., Schroeder, A.L. and Galeazzi, D.R. (1978). A meiotic UV-sensitive mutant that causes deletion of duplications in Neurospora. Genetics 89: 245-269.

Olive, L.S. (1954). Heterothallic behavior in the Aspergillaceae.Mycologia46: 254-255.

Perkins, D.D. and Barry, E.G. (1977). The cytogenetics of Neurospora. Adv. Genet. 19: 133-285.

Pontecorvo, G., Roper, J.A., Hemmons, L.M., McDonald, K.D. and Bufton, A.W.J. (1953). The genetics of Aspergillus nidulans. Adv. Genet. 5: 141-238.

Schroeder, A.L. (1975). Genetic control of radiation sensitivity and DNA repair in Neurospora. In: Molecular Mechanisms for Repair of DNA, part B, (Hanawalt, P.C. and Setlow, R.B., eds.). Plenum Press, New York, pp. 567-576.

Smith, G. (1957). An Introduction to Industrial Mycology. Arnold, London, 399 pp.

Smith, D.A. (1975). A mutant affecting meiosis in Neurospora. Genetics 80: 125-133.

Snedecor, G.W. and Cochran, W.G. (1972). Statistical Methods, 6th edn. The Iowa State University Press, Ames, 593 pp.