Cytogenetic Studies on Some Kashmir Grasses. VIII

Tribe Agrostideae, Festuceae and Paniceae

Abstract

Meiotic studies have been carried out in 33 species belonging to 3 tribes namely Agrostideae, Festuceae and Paniceae of the family Poaceae. The gametophytic chromosome number in these species range from n=7 to 36. These taxa exist in 33 cytotypes of which 73% are poly-ploids and 27% diploids. Cytology of Calamagrostis stoliczkai and Polypogon viridis has been studied for the first time. New chromosome counts have been recorded in Agrostis munroana, Digitaria cruciata and Phleum himalaicum.
Two base numbers i.e. x=7 and 9 have been observed in the 33 taxa studied. The taxa belonging to the tribes Agrostideae and Festuceae have the same base number (x=7) while as plants of the tribe Paniceae have base number x=9. While meiosis is normal in all the diploids and 18 polyploid taxa, in 6 polyploid species meiosis is abnormal characterized by the presence of quadrivalents besides bivalents at diplotene and metaphase-I stages indicating towards their segmental allopolyploid nature. In tetraploid Pennisetum orientale associations involving upto five chromosomes are observed which point towards the presence of interchanges superimposed on polyploidy.