結合組織培養與放射線照射誘導鳳梨變異之研究

Studies on the Combination of Tissue Culture and Gamma Ray Iirradiation to Induce Pineapple Mutations.

切取鳳梨組培苗帶有莖節之培植體，先行培養使其產生叢生狀芽原體，再以伽瑪射線照射誘導變異。第一年試驗照射劑量為0、25、35、45Gray等四種，處理之後二個月獲得葉部具有嵌紋之變異枝條，四種處理出現變異枝條之比率分別為0、0.4、0.5及0.8%，隨處理劑量之增加，變異率似有增高之趨勢。第二年試驗照射劑量為60、75及90Gray三種，以未照射者為對照，四種處理出現嵌紋變異枝條之比率分別為3.7、5.8、1.7及1.5%（對照）。結果顯示，鳳梨組織培養之芽原體，以75Gray之放射線照射劑量，可獲得較高比率之變異枝條。變異枝條經5個月繼代培養後，其葉片仍維持具有嵌紋性狀者，二年試驗總計分別獲得6及17株。 Pineapple multiple bud primordial, which came from an in vitro grown plantlets stem node through tissue culture, were treated with gamma ray to induce mutation. In the first year result, four irradiation doses, 0, 25, 35, and 45 Gray were used, mutants with chimerical leaves were obtained, and mutation rate were 0, 0.4, 0.5 and 0.8%, respectively in four treatments after treated two months. It seems that mutation rate could be increased along with increasing of the dosage. In the second year, three irradiation doses, 60, 75, and 90 Gray were used, together with a non­irradiation control. The mutation rate was 3.7, 5.8, 1.7, and 1.5%, respectively in four treatments. It has shown that the highest mutation rate was obtained by 75 Gray treatment. After five months sub­cultured, the total number of mutants, which maintained chimerical characteristics, were 6 and 17, respectively, in the first and second year experiment.