MEIOSIS AND POLLEN FERTILITY IN HIGO CHRYSANTHEMUM (DENDRANTHEMA X GRANDIFLORUM (RAMAT) KITAM)

To understand the cytogenetic behaviors and pollen resource potentiali ties, meioses and pollen fertility were examined in the 16 cultivars o f Higo chrysanthemum (Dendranthema x grandiflorum (Ramat.) Kitam.). Bi valent formation was highly regular at metaphase I in the pollen mothe r cells of all the cultivars although univalents and quadrivalents wer e also sporadically distributed. Considerable abnormalities such as la gging chromosomes and chromosome bridges at telophase I and II, and un equal sizes and abnormal numbers of microspores at tetrad stage were o bserved in the succeeding stages of microsporogenesis in all the culti vars. Pollen fertility varied from 0.4 to 97.7% among the cultivars an d they could be grouped into 3: high (71 similar to 100%), 8 cultivars ; intermediate (31 similar to 70%), 5 cultivars; and, low (0 similar t o 30%), 3 cultivars. It is indicative from the above results that majo rity of the cultivars of Higo chrysanthemum are potential pollen resou rces for the improvement of modern chrysanthemums.