Size and alkaloid content of seeds in induced autotetraploids of Datura innoxia, Datura stramonium and Hyoscyamus niger

Alkaloid content and metric features of seeds in diploid and induced autotetraploid Datura innoxia Mill., D. stramonium L. and Hyoscyamus niger L. were studied. As a result of chromosome doubling, the seeds of tetraploid forms were larger and heavier. Scopolamine was the main alkaloid in both ploidy levels of D. innoxia and H. niger whereas hyoscyamine was the main alkaloid in D. stramonium. The tetraploid seeds of Datura innoxia, D. stramonium and hyoscyamine niger had 1.86-, 1.65- and 1.96-times higher alkaloid contents compared to the seeds of the diploid form. The scopolamine to hyoscyamine ratio in tetraploids was higher in both Datura species and lower in Hyoscyamus niger. The increased size and alkaloid content makes tetraploid seeds a better source of alkaloids than diploid seeds.