蘆筍的細胞遺傳學研究 II.人為誘致倍數體之研究

Abstract

本試驗之目的為尋求蘆筍種子，以秋水仙素處理誘致四倍體之最佳處理濃度與時聞，供蘆筍育種之參考。結果顯示，以發芽當天或第二天之種子處理為佳，在23~28℃ 室溫下，四倍體之誘變率以0.5%，15 小時處理者為最佳。成活之植株均經形態及細胞學上染色體數之觀察，以鑑別其為二倍體、四倍體或混數體之植株。觀察10 株混數體之植株中，有6 株四倍體細胞數多於二倍體，4 株之四倍體細胞數少於二倍體之現象，此可能對蘆筍植物之進化過程有重要之關連。同時進行不同性別品種（系）間親本不同花青素雜交後代花青素特性之調查，以便瞭解其後代遺傳關係，確立無花奇素品種（系），供日後無花青素品種育種之參考。 The objective of this experiment is to obtain tetraploid asparagus plants for breeding purpose. Tetraploid asparagus plant can be induced by treating the germinating asparagus seeds with colchicine. The best result obtained by treating germinating asparagus seeds, within 24 or 48 hours of germination, with 0.5% colchicine solution for 15 hours at 23-28°C. Morphological and cytological examination of the asparagus plants showed that the survived colchicine-treated plants had three types, namely, diploids, tetraploids and mixoploids. Among the ten mixoploid plants examined, 6 plants showed more 4X cells while the other 4 plants had less than diploids. This may have played an important role in the evolution of asparagus plants. In order to examine the inheritance nature of the anthocyanin-free characteristics of asparagus, the progenies of the cultivar Connover’s Colossal were investigated. This could serve as a breeding tool for developing anthocyanin-free lines of asparagus cultivars.