Meiotic Behaviour in Perennial Ryegrass (Lolium perenne L.), Meadow Fescue (Festuca pratensis Huds.) and Their Triploid Hybrids

Authors: Bilal DENİZ

Abstract: This study was carried out in the glasshouse of the Agronomy Department of Agricultural Faculty. Atatürk University in summer 1993. In this study, metaphase 1 (MI) chromosome pairing and anaphase 1 (AI) segregations were studied in diploid perennial ryegrass (Lolİum perenne L.) and eutetraploid meadow fescue (Festuca pratensİs Huds.) and their artificial triploid hybrids (Festuca Ioiİaceum). Diploid perennial ryegrass had very regular meiosis with mainly ring bivalents at MI and with mostly balanced chromosome segregations at AI. Artificial eutetraploid meadow fescue had somewhat irregular meiosis with univalents and multivalents in MI. but bivalent pairings were often observed. AI segregatians were generally balanced and some unbalanced ones were also seen. Intergeneric triploid hybrids showed very regular chromosome association. Most chramasomes formed bivalents though univalents and quadrivalents were rarely observed. However . all the hybrids had the expected anequal chromosome segregations and other disjunction abnormalities at AI. In a number of hybrid plants. significant differences in terms of chromosome pairings and segregations were also seen. Meiosis in triploid were more irregular than their parents. No triploid plants with a regular and stable meiosis were found.

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