Meiotic Phenomena in Certain Gramineae. II. Paniceae and Andropogoneae

Abstract

The following representatives of these 2 tribes have been found to fall in the groups of chromosome multiples as listed Diploids[long dash]Paspalum muhlenbergii, Panicum lindheimeri in its 4 varieties, P subvillosum, P tsugetorum, P sphaerocarpon, P scribnerianum; Tetra-ploids[long dash]Digitaria sanguinalis, Panicum miliaceum, Sorghastrum nutans; Hexaploids[long dash]Panicum dichotomi-florum, Echinochloa crus-galli, Miscanthus sinensis v. zebrinus; Octoploids[long dash]Echinochloa frumentacea, Andropogon scoparius; Decaploid[long dash]Andropogon furcatus. Lagging univalents are found in Andropogon scoparius. Non-disjunction is reported in Panicum lindheimeri v. fa ciculatum. Polyspory is found only in Panicum lindheimeri v. typicum. Irregularities in the chromosome count are reported in several members of Panicum. Cytomyxis is found to extend throughout the diakinesis and heterotypic metaphase in several species. Varying degrees and combinations of non-pairing, lagging and extrusion, cytomyxis, polycary and sterile pollen are frequently seen. Polyploidy or cytological abnormalities of the maturation divisions or both are considered as evidence of the hybrid origin of these species.