Department of Genetics, Faculty of Agriculture, University of Cairo, Giza, Egypt.
Theor Appl Genet. 1979 Jan;54(1):17-25. doi: 10.1007/BF00265703.
Flowering time, plant height and flower size in Petunia hybrida Hort. (multiflora type) have been genetically analysed by means of a 5 × 5 diallel cross. The results indicated that: (1) the three characters are controlled by additive-dominance polygenic systems. The contribution of the additive gene actions to the genetic variance of flowering time was relatively higher than that of dominance. The reverse situation was found for plant height and flower size. (2) Dominance is ambi-directional for the three characters. Ratios of average dominance were in the range of partial for flowering-time, complete for plant height and overdominance for flower size. (3) Number of genes (or gene groups) controlling the characters are about 3, 3 and 5 for flowering time, plant height and flower size: respectively, (4) Heritability estimates are 0.84, 0.88 and 0.89 in the broad-sense and 0.40, 0.49 and 0.37 in the narrow-sense, for flowering time, plant height and flower size; respectively. (5) Heterosis as percent increase of the mean F1-hybrid above the higher parent, or decrease below the lower parent, was observed for flowering time (+ 9.7% to +13.3%), for plant height (-13.6% to -20.3%) and for flower size (+2.5% to +16.0%).
矮牵牛杂种（多花型）的开花时间、株高和花朵大小已通过 5×5 完全双列杂交进行了遗传分析。结果表明：（1）这三个性状受加性-显性多基因系统控制。开花时间的加性基因作用对遗传方差的贡献相对较高，而株高和花朵大小则相反。（2）三个性状的显性均为双向。平均显性比率在开花时间为部分显性，株高为完全显性，花朵大小为超显性。（3）控制这些性状的基因（或基因群）数分别约为 3、3 和 5 个，用于开花时间、株高和花朵大小。（4）开花时间、株高和花朵大小的广义遗传力估计值分别为 0.84、0.88 和 0.89，狭义遗传力估计值分别为 0.40、0.49 和 0.37。（5）杂种 F1 代相对于高亲的平均优势表现为增加（+9.7%至+13.3%），相对于低亲的平均劣势表现为降低（-13.6%至-20.3%），而花朵大小的杂种优势表现为增加（+2.5%至+16.0%）。
