Cytology of hyphal interactions to determine mating types in Morchella esculenta

Abstract

Presently cultivation process of Morchella esculenta is a US patented technology. Limited information is available on cytology and the life cycle is ambiguous. Monosporous cultures were raised to study the cytology of hyphal interactions to determine mating types in M. esculenta. Hyphal interactions were performed in dual cultures (i) between eight monospores of the same ascus, (ii) between monospores of two different asci of the same ascocarp, (iii) between monospores of two asci of different ascocarp in M. esculenta. Three types of mycelial interactions were recorded. All self interactions did not formed any mycelial meld or fluffy zone in the confronting region. Hyphal interaction between ascospores of same ascocarp and asci from different fruit bodies resulted in formation of horizontal fluffy zone whereas some interactions formed longitudinal fluffy zone. An epifluorescent staining technique with DAPI and Calcoflour was developed, which confirmed nuclear exchange in horizontal fluffy zones. The cytological evidences validate heterothallic nature of M. esculenta. Present study is of significance for cultivation Morchella under controlled conditions.