The Mitotic Index in Diploid and Triploid Allium Roots

Abstract

Continuous light, with or without aeration, did not eliminate the midday peak of the mitotic index in root tips of diploid and triploid Allium triquetrum. However, when plants were grown in continuous darkness with aeration, the midday peak of the mitotic index was no longer evident. Aeration of the tap water in which the roots were grown increased the mitotic index in both 2X and 3X roots, indicating that a greater number of meristematic cells were dividing. Triploid root tips had a higher mitotic index than diploid root tips, partly because of an increase in the length of mitosis.