| 摘要: | 甘藷適應性廣，是少數全株皆可被利用的雜糧與蔬菜作物。傳統育種方法耗時，且受環境影響，使用分子標誌技術如輔助標誌選拔(Marker-assisted selection, MAS)分析，可提高育種效益。本研究使用甘藷’臺農57號’(TN57)與’清水紫心’(CP)做為親本，利用其正、反交之F1做為mapping population，調查親本及F1之莖葉重、塊根數量、塊根重、皮色、肉色、糖分、澱粉、直鏈澱粉與粗蛋白等9個外表型性狀。隨機抽取正反交各100個樣本，以Inter Simple Sequence Repeat (ISSR)與Amplification fragment length polymorphism (AFLP)分子標誌進行MAS研究，最後定位數量性狀基因座(QTL)，並繪製基因連鎖圖譜。研究結果顯示正交(TN57×CP)外表型性狀之間呈顯著相關的有7組，反交(CP×TN57)外表型性狀之間呈顯著相關的有9組。正交與反交的莖葉重與塊根重有顯著差異，表示此兩性狀之遺傳具有母系效應。在粗蛋白含量之性狀則具有雜種優勢。ISSR與AFLP之QTL分析得到正交2個連鎖群與反交3個連鎖群。在正交子代連鎖群發現13個QTL，分別為莖葉重1個、塊根重5個、塊根皮色1個、塊根數目1個、直鏈澱粉2個、糖含量2個、粗蛋白含量1個；反交子代連鎖群發現4個QTL，分別為莖葉重1個、塊根重1個、塊根個數1個、糖分含量1個。而這些與甘藷產量及品質QTL連鎖之marker可作為日後雜交育種的選種標誌，並縮短育種年限。
Sweet potato is widely adapted and one of the most economically important crops in the world. Controlled reciprocal crosses were made between sweet potato ‘Tainung 57’ (TN 57) and ‘Chinshey purple’ (CP). Trait measurement included : fresh weight of tops, root skin color and root flesh color, fresh root weight and number, percentage crude protein content, percentage starch content, percentage amylose content, and percentage soluble sugar content in storage root. The correlations between traits were analyzed. The results indicate that substantial differences of mean and coefficients of variation in the measured traits existed in the F1 populations. Maternal effects on top weight and root weight was observed. Top weight, root weight and crude protein of the hybrids were heterotic. Significant correlations were detected among top weight, root weight and root number, between root shape and top shape and root weight, between root skin color and root flesh color, and between starch content and amylose content. Combination of the mentioned 9 traits and the informative ISSR and AFLP markers, two linkage groups were constructed, and 13 QTLs of traits linked to the markers were identified under TN57 x CP. Among these QTLs, 1 of them linked to top weight, and 5 linked to root weight, etc. In the case of CP x TN 57, three linkage group was created and 4 QTLs were identified on it. Using these informative markers as selection marker to improve these economic traits will reduce breeding cycles in the existing breeding practice. |
