It is possible to induce apogamous sporophytes and aposporous gametophytes in some bryophytes under cultural conditions. Among the factors which favour apogamy are reduced hydration, low light level, high sugar concentration, chloral hydrate, low concentration of hormones, coconut milk, ‘sporogon factor’, high chromosome number and heritable variations. Apospory is favoured by suitable temperature and light, wounding, removal of apical dominance, sufficient humidity and lack of sugar in the medium. Being rare in nature, these phenomena do not have much significance in the life cycle of bryophytes. However, these have resulted in increased ploidy level in some mosses. These phenomena support the ‘homologous’ theory of the origin of alternation of generations, and have also helped in the understanding of some aspects of differentiation.
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