甜椒的遺傳與育種行為之研究（二）產量構成要素之完全互交法分析

Studies on Genetic Behavior and Breeding of Sweet Pepper (Ⅱ) A Diallel Analysis of Yield Components in F1 Progeny

(1)以六個甜椒品種進行全互交，利用F1及親本後代為材料，依據Hayman之統計分析原理及方法，研究果柄長、萼片大小、果長、果寬、果肉厚、果重、果數及產量等8個產量構成因素之遺傳，結果如下：(1)所有的調查性狀，由品種間平均效果所引起的遺傳變異甚大。除果寬外其他7個性狀均具有單向之顯性作用。一般其雜種優勢均呈正值，亦即各性狀之大者為顯性。(2)除果數及產量外，其他6個性狀之遺傳，均受細胞質之影響。(3)支配果長及果數之顯，隱性之因子頻度相等，而支配其他6個性者狀則均不相等。(4)由迴歸分析發現萼片大小，果長，果寬及果肉厚為部份顯性及累加性。但果重、果數、產量及果柄長為超顯性，均具有非對立因子間之交感作用。(5)支配果長、果重及產量之顯隱性因子總數大約相等，惟顯性稍多；而支配萼片大小、果寬之顯性因子約為隱性因子數之2倍，至於果柄及果肉厚則約為3倍。但果數，則隱性因子數較多。(6)至少有3~5對因子群各支配果肉厚、果數、果重及產量之遺傳，而其他性狀受微效因子所支配。(7)遺傳力除萼片大小、果肉厚、果長及果寬外，其他則偏低。(8)六個親本中顯性因子多者與果柄長、果長、果寬及果肉厚較大者有關聯，同時與果重較重且產量較高者有密切關係。

A diallel analysis of six sweet pepper cultivars and their all possible crosses were used to study the genetic behavior of stalk length, calyx size, fruit length, fruit width, flesh thickness, number of fruit, fruit weight and total fruit weight according to Hayman's method. Results were as follows: 1. The genetcial variation of all characters were highly singificant among these six parents. The unidirectional dominance effect is present in all characters except fruit width. A positive heterosis value was found in the characters and dominance was in the direction of higher value. 2. Maternal effects were existed in the characters except number of fruit and total fruit weight. 3. The gene frequencies of dominance and recessive were equal m the characters of fruit length and number of fruit but were not in others. 4. Regression analysis indicated an additive and partially dominant genes effect were exsisted in the characters of calyx size, fruit length, fruit width and flesh thickness. Overdominant genes effect and non-allelic interaction were present in the characters of stalk length, fruit weight, number of fruit and total number of fruit. 5. The total number of dominant and recessive alleles were apporximately equal in fruit length, fruit length, fruit weight and total number of fruit. The total number of dominant genes was about 3 times greater than the recessive genes in the character of calyx size and fruit width and was 2 times in the character of stalk length and flesh thickness. But the number of recessive genes was greater than dominant genes in number of fruit. 6. There were at least 3 to 4 factor pairs influencing the characters of flesh thickness, number of fruit, fruit weight and number of total fruits while others were controlled by polygenes. 7. The heritability values were low in the characters except calyx size and flesh thickness 8. The higher value in the characters of stalk length, fruit length, fruit width and flesh thickness were related to the greater number of dominant genes and also showed a close relationship with heavy fruit weight and total fruit weight.