Meiotic Phenomena in Certain Gramineae. II. Paniceae and Andropogoneae

Abstract

1. The following representatives of the tribes Paniceae and Andropogoneae have been investigated: Diploids.-Paspalum muhlenbergii, Panicum lindheimeri in its four varieties, P. subvillosum, P. tsugetorum, P. sphaerocarpon, P. scribnerianum. Tetraploids.-Digitaria sanguinalis, Panicum miliaceum, Sorghastrum nutans. Hexaploids.-Panicum dichotomiflorum, Echinochloa crus-galli, Miscanthus sinensis var. zebrinus. Octoploids.-Echinochloa frumentacea, Andropogon scoparius. Decaploid.-Andropogon furcatus. 2. Lagging univalents are found in Andropogon scoparius. 3. Non-disjunction is reported in Panicum lindheimeri var. fasciculatum. 4. Polyspory is found only in Panicum lindheimeri var. typicum. 5. Irregularities in the chromosome count are reported in several members of Panicum. 6. Cytomyxis is found to extend throughout the diakinesis and heterotypic metaphase in several species. 7. Varying degrees and combinations of non-pairing, lagging and extrusion, cytomyxis, polycary, and sterile pollen are found in the species investigated. 8. Polyploidy or cytological abnormalities of the maturation divisions or both are considered as evidence of the hybrid origin of these species.