Foeniculum vulgare: Polyploidy, Translocation Heterozygosity and Pollen Variability Part I. Cytology

Abstract

The present study deals with the effect of colchicine-gammexane treatment on Foeniculum vulgare which leads to the production of tetraploid, mixoploids and diploid plants which exhibited pollen variability. E. 139. In this 2n plant the cytological behaviour was normal but it had 90% variable pollen grains which included giant and bichambered grains also. E. 147. Though diploid it showed multivalent formation. Meiosis is considerably irregular. It also exhibited cytomixis and syncyte formation. Nuclear migration between cells takes place as late as T. II. E. 151. In this diploid plant a good proportion of PMC's had normal stages but a few showed laggards, strays and bridges. It exhibited development of exceptionally large giant pollen grains resembling embryosac like structures. It had giant as well as joined pollen grains which show transfer of nuclei and cytoplasmic material from one grain to another. E. 182. (4n) The meiotic instability was considerable. It is characterised by very low frequency of multivalents. The possibility of certain genes controlling the pairing has been discussed. This plant also exhibited splitting of nuclei at T. I which resulted into multiple spindles at M. II. This is caused by the splitting of the spindle organizers. © 1966, Japan Mendel Society, International Society of Cytology. All rights reserved.