CYTOGENETIC STUDIES ON REGENERATED PLANTS DERIVED FROM PROTOPLASTS OF ACTINIDIA DELICIOSAⅢ.LIGHT MICROSCOPE INVESTIGATION ON CHROMOSOME PAIRING OF FIRST MEIOTIC DIVISION IN POLLEN MOTHER CELLS OF MOTHER PLANT

Chromosome pairing of first meiotic division in pollen mother cells (PMCs) of Actinidia deliciosa No.26 (the mother plant of protoplast-derived plant) investigated microscopically was first repor ted in this paper.It was indicated that the chromosome pairing and condensation were not synchronous obviously.Greater variation appearred in the form of chromosome pairing in different PMCs.Among them,the main form was bivalent synapsis;multivalent was formed by various pairing forms,such as complex pairing,repeated pairing,association by telomeres or centromeres,and multivalent synapsis;and there were few unpaired or inter paired univalent (occasionally),and secondary pairing between some bivalents.Some structural variations,such as chromosome deficiency (or duplication),inversion,translocation,and loose pairing can be observed at pachytene stage.These phenomenans illustrated that this mother plant is a complicated segmental allohexaploid,and structural variations occur in some chromosomes.It is suggested that this mother plant is an excellent material for the studies on the mechanism of chromosome pairing and synopsis in meiosis.