Seeds V. villosa (hairy vetch) were treated with 0.005% colchicine and 12% tetraploid plants (2n=4x=28) were obtained. Besides two chimeric plants, one of them consisted of diploid, triploid, tetraploid, hexaploid, heptaploid, octoploid roots and the other diploid and triploid roots were also obtained in hairy vetch. Tetraploid plants were determined by the chromosome numbers in the root tips which were confi rmed by studies conducted in the pollen mother cells (PMCs). Chromosome irregularities in the PMCs of diploids were not observed, however normal and abnormal chromosomal behavior were detected in tetraploids. The morphological observations pointed out those tetraploids were shorter, surface of leaves were greater, and size of stomata were bigger but the number of stomata in per area were less than diploids. Flowering was delayed in tetraploids, the number of fl owers was less, but forming a few larger fl owers than diploids. It was also observed that the colour of leaves was darker, and amount of total chlorophyll in the leaves was higher in tetraploids. Pollen grains also showed some differences in diploids and tetraploids. While diploid pollen grains had tricolporate, numbers of pore and colpi showed variations in tetraploids; pollen grains with 4 pores and 4 colpi, 5 pores and 5 colpi and 6 pores and 6 colpi were identifi ed. The pollen size in the tetraploids was defi ned bigger than others. There were differences in the shapes of pollen grains; they were elliptical in diploids, triangular in polyploids. Pollen viability was measured as 99% in diploids, and this rate lowered to 81% in tetraploids.

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The genotoxic and cytotoxic effects of exogenous polyamines (PAs), putrescine (Put), spermidine (Spd), spermine (Spm) and PA biosynthetic inhibitors, alpha-difluoromethylornithine (DFMO), cyclohexilamine (CHA), methylglioxal bis-(guanylhydrazone) (MGBG) were investigated in the root meristems of Allium cepa L. The reduction of mitotic index and the induction of chromosomal aberrations such as bridges, stickiness, c-mitotic anaphases, micronuclei, endoredupliction by PAs and PA biosynthetic inhibitors were observed and these were used as evidence of genotoxicity and cytotoxicity.

In Lathyrus undulatus Boiss. (Fabaceae), the young microspore stage of anther development was characterized by the enlarged secretory tapetal cells, which presented an intense reaction with regard to protein, insoluble polysaccharides and lipids. At bicellular pollen stage, the middle layer and the tapetum degenerated. After degradation of the tapetum, epidermis and single row U-shaped endothecium existed in the mature anther wall, and pollen grains remained in the locus. Young microspores had a spherical and centrally located nucleus with one or two nucleoli, many spherical lipid bodies and starchy plastids. A mature pollen grain contains insoluble polysaccharides, proteins, lipids and calcium. The mature pollen had the following morphological characteristics: 3-zonocolporate, prolate, tectate (imperforate) type of exine and perforate type of structure. The intine formed an important constituent portion of the wall, and consisted two sublayers: an outer intine (exintine) and an inner intine (endintine). The well-defined exine was made up of lipoidal substances and protein, but the intine composed of insoluble polysaccharides and protein.The bicellular state of the pollen grains persisted to anthesis.