國立臺灣大學植物病理與微生物學系暨研究所張慧羽2006-07-262018-06-292006-07-262018-06-291999http://ntur.lib.ntu.edu.tw//handle/246246/17664雖然果蠅的微小染色體相當小但仍具 有重要的遺傳功能。許多種果蠅的微小染 色體在長度上有種間或種內變異的情形， 而其差異來自於異染色質量的不同，推測 可能是 Y 染色體轉位的結果。我們以往的 研究顯示，若將印度輝顏果蠅 (Drosophila nasuta) 雄蟲與日本石垣島紅果蠅 (D. albomicans) 雌蟲做種間雜交，雜交族群的 微小染色體大都會固定為紅果蠅的型式。 推測也許是紅果蠅長型的微小染色體在選 汰上佔優勢。本年度計畫將不同地理品系 的輝顏果蠅與紅果蠅做組合配對，以建立 數個種間雜交族群。再累代培養後對雜交 後代進行核型分析，以了解不同長度的微 小染色體是否有選汰上的差異。實驗結果 顯示紅果蠅長型的微小染色體在選汰上並 不佔明顯的優勢。In Drosophila, the microchromosomes have essential genetic function in spite of their small size. Inter- or intraspecific variation in length of microchromosomes was discovered in many Drosophila species. The difference was contributed to different amount of heterochromatin, and it might also be due to a translocation with Y chromosome. A previous report of ours indicated when an Indian D. nasuta male crossed with a Okinawa D. albomicans female, a tendency of reaching fixation to the albomicans type of microchromosome was observed in the hybrid offspring. Since the microchromosome of D. albomicans is larger, there may exist selective advantage. Therefore, we make interspecific crosses in order to find out whether this tendency holds. Taking the characteristics of interspecific difference in length of microchromosomes between D. albomicans and D. nasuta, hybrid populations were established by crosses between different geographical stocks of these two Drosophila species. Those hybrid populations have been reared by non-overlapping generation method. The result of the karyotype assay suggests no obvious selective advantage of the albomicans type microchromosome.application/pdf29132 bytesapplication/pdfzh-TW國立臺灣大學植物病理與微生物學系暨研究所微小染色體輝顏果蠅紅果蠅種間差異Drosophila albomicansD. nasutainter-specific differencemicrochromosomesotherhttp://ntur.lib.ntu.edu.tw/bitstream/246246/17664/1/882313B002006.pdf