外表型混合選拔法與同親兄妹輪迴選拔法對玉米台南白鮮果穗產量改良之效果

Abstract

為評估外表型混合選拔法與同親兄妹輪迴選拔對玉米台南白改良效果大小。利用經過改良之族群及原始台南族群為材料，於1997年秋作，在霧峰及崙背兩地點進行比較試驗。歷經三年，春作及秋作連續選拔後，由兩地點之平均，顯示應用外表型混合選拔法六個循環選拔，對非目標性狀如開花期、吐絲期及高而言並沒有明顯的改變，而對吐絲期則呈現提早之現象。對選拔性狀如穗位高及去苞葉果穗鮮重則有少量的影響，其去苞葉鮮果穗產量的增加僅為3.04%，改良之效果不明顯。而同樣經過三年兩個循環的同親兄妹輪迴選拔後，顯示對開花期及株高兩性狀均呈增加現象；對吐絲期、穗位高及穗長則沒有明顯改變；而對含苞葉果穗鮮重及去苞葉果穗鮮重均有顯著的改良效果，分別較原始族群增加19.01%和16.79%。就族群產量改良的效率而言，以同親兄妹輪迴選拔法較優於外表型混合選拔法。 Six cycles of mass selection, two cycles of full-sib recurrent selection, and the original Tainan-white (TNW) maize population were available in this study. All the material planted at Wufeng and Lunpei in the fall of 1997. Ear height, ear length and fresh weight were the major seleceted tarits in this experiment. The results indicated that no significant response was detected on the yield of Taichung TNW population followed by six cycles of mass selection. However, the average yield of Taichung TNW population were significantly improved by two cycles of full-sib recurrent selection. Across the two locations, the response of fresh weight of ear with husk and ear fresh weight to full-sib recurrent selection from C0 to C2 increased 19.01% and 16.79%, respectively. It showed that the efficiency of population improvement by the full-sib recurrent selection is better than that of mass selection on yield.