FLOWER CULTURE OF A MALE STERILE STAMENLESS‐2 MUTANT OF TOMATO (LYCOPERSICON ESCULENTUM)

Abstract

Young floral buds of a male sterile stamenless‐2 (sl‐2/sl‐2) mutant of tomato were cultured, at the sepal primordia stage, in a liquid Murashige and Skoog medium containing either benzylaminopurine (BAP) or gibberellic acid (GA3) or both. In the basal medium (BM), the buds initiated petal and stamen primordia only and they showed limited development. In buds grown in BM supplemented with 10–6 M BAP, all types of organ primordia were initiated but the petals remained small and the stamens and carpels were immature. Well‐developed flowers with a normal complement of floral organs were, however, produced in a medium containing both BAP (10–6 M) and GA3 (10–7 M to 10–5 M). The development of stamens was variable and ranged from the complete absence of microsporogenesis to the formation of abnormal pollen. Gynoecium development was normal and ovules with megaspores were produced in the ovary. The results show that male sterility in the sl‐2/sl‐2 mutant can be expressed in vitro and that GA3 is essential for the in vitro growth and development of all the floral organs of this mutant.