HISTOLOGY OF SOMATIC EMBRYO INITIATION AND DEVELOPMENT IN CHICKPEA (CICER-ARIETINUM L)

The histology of somatic embryo initiation and development in chickpea (Cicer avietinum L.) from different explants was studied. Immature co tyledonary segments, immature embryo axes and mature embryo axes of cu ltivar PG12 were cultured on Murashige and Skoog's (MS) basal medium s upplemented with 3.0 mg/l 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) with and without a gelling agent. In addition, young leaflets of culti var C235 and immature embryo axes of cultivar PG5 were also cultured o n MS basal medium supplemented with 1.25 mg/l 2,4-dichlorophenoxyaceti c acid (2,4-D)+ 0.25 mg/l kinetin and 3.0 mg/l 2,4-D + 0.1 mg/l 6-benz ylaminopurine (BAP). Explants with different developmental stages of s omatic embryos were fixed for histological examination, cut to 10 mu m thick sections, stained with hematoxylin-eosin and observed microscop ically. Histological studies revealed that somatic embryos arose indir ectly with an intervening callus phase from immature cotyledons and im mature embryo axes, directly from mature embryo axes and by both route s from young leaflets.