Comparaison des aptitudes morphogénétiques des étamines fertiles ou stériles d'Actinidia chinensis cultivées in vitro

Abstract

High frequency plantlet regeneration is obtained by means of in vitro culture of neoformed roots arising from Actinidia chinensis Pl. stamens. The favourable influence of zeatin upon bud initiation from roots is demonstrated. Potential differences between stamens coming from ♀ or ♂ plants are also shown. On the same medium, sterile stamens exhibit a greater rooting potential than fertile ones, but the latter have a more pronounced callusing efficiency. These differences are transmittable through dedifferentiation; neoformed roots of ♂ origin have a weak bud regeneration ability, whereas roots of ♀ origin give rise to callus and buds. The implications of such observations in regard to the endogenous contents of auxins and cytokinins and their relations with the ♀ or ♂ nature of the plants are discussed. The histological origin of the different kinds of regeneration are also examined and point to the preservation of rooting potential by the bundle sheath of the stamens and of budding potential by the pericycle of neoformed roots. These data are considered in relation to the recent literature.