A diallel study of yield components and essential oil constituents in basil (Ocimum basilicum L.)

This study aimed to estimate the general and specific combining abilities of basil by analyzing its essential oil content and main chemical compounds. The study was conducted at the “Campus Rural da UFS” Research Station, located in São Cristóvão, Sergipe. Four cultivars with different chemical compositions were selected and diallel crosses were performed. The F1 seeds and the parents were planted in a randomized block design in triplicate. Data were evaluated using Griffing's diallel analysis, model 2, and the means were grouped by the Skott–Knott test (p ≤ 0.05). Plant height, crown diameter, leaf length, leaf width, leaf dry weight, essential oil content and yield, and chemical constituent content were recorded and examined. Analysis of variance for combining ability indicated that the effects of the General Combining Ability (GCA) showed significant differences and the effects of the Specific Combining Ability (SCA) in crosses were significant, except for the length and width of leaves. For almost all the features tested, both additive and nonadditive effects influenced the hybrids’ performance.

► Maria Bonita showed a positive GCA effect for eight variables, inclusive linalool.
► Hybrids of Sweet Dani, Maria Bonita, and Genovese presented highest SCA values.
► Cultivars with high linalool can be obtained from hybrid Sweet Dani × Maria Bonita.
► Cultivars with high linalool can be obtained from hybrid Genovese × Maria Bonita.
► Hybrid Sweet Dani × Cinnamon can be used to increase essential oil yield and content.