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1.研究目的：台灣食用玉米台南白，已有80年以上之栽培歷史，深受消費
者喜愛，但外表性狀不整齊、果穗大小不一，產量偏低。本論文目的在瞭
解不同地區之台南白族群是否有明顯的差異存在及其遺傳變異之大小。針
對台南白進行性狀遺傳分析、雜種優勢表現及族群改良方面探究，以作為
台南白育種應用及遺傳理論之基礎參考資料。
2.研究方法：以不同地區之台南白族群及其分離之自交系，外來種源等為
材料進行F1雜種之生產，然後進行田間之產量評估及實驗室RAPD遺傳歧異
度之分析。
3.結果：(1)各地台南白族群性狀有明顯差異且有分化現象，(2)台南白S2
世代早期組合力檢定與S5世代檢定結果具有顯著相關，(3)RAPD遺傳歧異
度可作為玉米自交系雜種優勢類群之劃分，同時可用於預估F1雜種產量及
雜種優勢之大小，(4)產量係受GCA及SCA基因共同控制，顯性基因為增量
基因，至少受六群基因所左右，(5)F1雜種在不同期作下，表現較台南白
族群高產，且優良之組合表現極為穩定，(6)外種源與台南白之F1雜種表
現較台南白佳，顯然可作為台南白產量改良之育種材料。
Tainan-White(TNW) is a native maize population which has been cultivated
for over 80 years in Taiwan. The results showed significant differences
in many agronomic characters among the eight TNW maize populations. The
results indicate that the temperature of collecting sites maybe a main
factor for the differentiation of cultivars. Singnificant phenotypic
correlations were found between the S2 and later generation testcrosses
for yiield. Performance of S5 testcross could be precisely predicted from
that of S2 testcross, suggesting that early testing was effective for
evaluating relative combining abilities at later inbreeding generation.
Cluster analysis by the unweighted pair group method of arithmetic
means (UPGMA) showed that thirteen inbred lines could be classified
into different heterotic group with RAPD-similarity coefficients.
RAPD analysis was a useful tool in determining the genetic relationships
among maize inbred lines in the present case. There was a significant
correllation between the RAPD-based genetic distance and heterosis and
average performance for F1 Hybrids yield. The present results also suggest
that RAPD-Jaccard similarity coefficients can be used to predict the
yield performance or heterosis for F1 hybrids yield. In a 13×13 diallel
analysis, significant differences in tested traits among genotypes were
observed. In general, the average yield, general combining ability (GCA)
effect, specific combining ability (SCA) effect and heterosis
of interpopulation
crosses were greater thatn that intrapopulation crosses. And most of F1 hybrids
derived from interpopulation had higher yield than the TNW population. The
gene--effect analysis, indicated the GCA and SCA effect are significantly
for all the agronomic characters. The ear dry weight and grain dry weight
was controlled by six group of dominant gene, and the dominant gene might
be the increasing genes. During four crop seasons compared the yield and
agronomic characters with open-pollinated TNW population, hybrids of E×G,
H×E and H×G has been selected. And these hybrids had eight row number,
larger kerneels, longer ear length, higher yield, better plant type and
resistance to lodging. Some F1 hybrids among exotic inbred lines producted
hight yield in ear fresh weight and grain dry weight than did the open-
pollinated TNW population. Heterotsis existed among TNW inbred line and
CML76, CML93, CML98. But the eating quality for green corn needs to be
furthar investigating.
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