In this study, attempts were made to fuse the suspension-derived protoplasts of a sugar beet breeding line (ÇBM315) with the mesophyll-derived protoplasts of three breeding lines (M114, ELK345 and M1017), which were obtained from our previous experiments. | Turk J Biol 26 (2002) 163-170 © TÜB‹TAK Protoplast Fusion in Sugar Beet (Beta vulgaris L.) Songül GÜREL Sugar Institute, Plant Breeding Department, Etimesgut, 06790 Ankara – TURKEY Ekrem GÜREL Abant Izzet Baysal University, Department of Biology, 14280 Bolu – TURKEY Zeki KAYA Middle East Technical University, Department of Biology, 06110 Ankara - TURKEY Received: Abstract: In this study, attempts were made to fuse the suspension-derived protoplasts of a sugar beet breeding line (ÇBM315) with the mesophyll-derived protoplasts of three breeding lines (M114, ELK345 and M1017), which were obtained from our previous experiments. Combinations of three different PEG concentrations (20%, 25% or 30%) and three different treatment durations (15, 20 or 25 min) were tested. The fusion efficiency was determined by measuring the viability, heterokaryon frequency and plating efficiency (PE) of the fused protoplasts after four weeks of culture. In general, 25% PEG combined with 20 min treatment duration produced the highest fusion frequency, but the highest rate of viability was obtained at 20% PEG with 25 min treatment duration. The capacity of heterokaryons to form cell colonies was highest when lower PEG (20 or 25%) was used for shorter treatment durations (15 or 20 min). No macrocallus or regeneration from the fused protoplasts was achieved. Key Words: Sugar beet, protoplast fusion, PEG, breeding lines fieker Pancar›nda (Beta vulgaris L.) Protoplast Füzyonu Özet: Bu araflt›rmada, daha önceki denemelerimizden elde edilen ÇBM315 adl› fleker pancar› ›slah hatt›na ait süspansiyon-kökenli protoplastlar ile yine üç fleker pancar› ›slah hatt›na (M114, ELK345 ve M1017) ait mezofil-kökenli protoplastlar›n füzyonuna çal›fl›lm›flt›r. Üç farkl› PEG (%20, %25 ve %30) ile üç farkl› uygulama süresinin (15, 20 veya 25 dakika) de¤iflik kombinasyonlar› denenmifltir. Füzyon etkinli¤i; canl›l›k, hetereokaryon s›kl›¤› ve füzyona u¤rayan protoplastlar›n PE (plating efficiency) .
