Microsporogenesis, Macrosporogenesis, and Development of the Macrogametophyte and Seeds of Duboisia Leighhardtii (F.v.M.) and D. Myoporoides (R.Br.)

Abstract

In Duboisia Leichhardtii and D. myoporoides macrosporogenesis and the development of the embryo-sac are similar to the descriptions reported for other genera of the family Solanaceae. The haploid number of chromosomes in both species is 30. A generative and vegetative nucleus is formed in each micros pore which later becomes filled with starch grains and uninucleate as a result of degeneration of the vegetative nucleus. At maturity the pollen grains are devoid of starch and are uninucleate. Division of the generative nucleus to form two male nuclei presumably occurs just prior to the discharge of the pollen tube.