Effects of Temperature During Ascus Formation and Frequency of Ascospore Discharge on Pseudothecial Development ofVenturia inaequalis

Abstract

The number of asci that developed in pseudothecia of V. inaequalis was determined by the temperature between the appearance of ascus initials and the appearance of ascospores. Varying the interval between ascospore discharges had no significant effect on production or maturation of asci when leaves were kept moist and pliable between discharges. There was no evidence of ascospore discharge by means of circumscissile dehiscence or bursting of pseudothecia. When ruptured pseudothecia were examined, the rupture of the ascocarp wall appeared as the result, rather than the cause, of senescence.