NUMBERS OF CHLOROPLASTS AND POLLEN GRAIN PORES IN DIPLOID AND TETRAPLOID VARIETIES OF SOME TRIFOLIUM SPECIES

In red clover (2n=14), berseem (2n=16) and in white clover (2n=32) the differences in the number of plastids in the leaf stomata and the number of germinal pores in the pollen grains between diploid and induced tetraploid plants was established. In all species the doubling of the chromosomes was followed by an increase in the number of plastids. This increase was about the same in all three species. The number of plastids in the stomata of the amphidiploid white clover was similar to that of the tetraploid types of red clover and berseem. The pollen grains of the diploid plants had almost exclusively three pores. The pollen grains of the chromosome doubled plants had predominantly more than three germinal pores. It was concluded that both characters can serve as useful indicators for establishing the polyploid level in the three clover species studied. © 1968 H. Veenman en Zonen N.V.