Haploid plants from in vitro anther culture of Annona squamosa Linn.

Haploid plants were induced from anther callus of Annona squamosa Linn. (Custard apple) on a Nitsch basal medium supplemented with 6-benzyl-aminopurine and naphthalene acetic acid. When naphthalene acetic acid was replaced by indole-3-acetic acid only multiple shoots were obtained. Pretreatment (chilling, centrifugation, reduced atmospheric pressure etc.) of the flowers was not effective but dissection of the flowers in a suspension of activated charcoal and sucrose was found essential. The anthers required an initial dark period and a high sucrose medium followed by light and lowered sucrose levels. Root tip squashes of the regenerated plantlets revealed the haploid (n = 7) nature of the plantlets.