This study aimed at evaluating the segregation, correlation and heritability of certain agronomic characters in F2 plants of oil palm (Elaeis guineensis Jacq.) which were collected and planted in 1989 at Klong Hoi Khong Research Station, Faculty of Natural Resources, Prince of Songkla University, Songkhla, Southern Thailand. The 1,038 palms collected at the age of thirteen-years derived from F1 Tenera hybrid plants were selected from oil palm plantations in different areas in Southern Thailand. Only one good performance bunch (i.e. big bunch with thin shell fruit) was selected from each plantation and four seeds per selected bunch were used for planting. The results showed that three types of oil palm could be distinguished by brown fiber ring in mesocarp and shell thickness of fruit, as having Dura, Tenera and Pisifera at 27.3, 49.8 and 22.9%, respectively. The presence of brown fiber ring character was controlled by a single gene pair with complete dominant action. The action of genes controlling shell thickness in fruit was additive. High variation was observed for agronomic charaters in F2 plants, e.g. fruit weight, %mesocarp/fruit, %shell/fruit, %kernel/fruit, number of bunch/plant, bunch weight and FFB yield. Correlations among these characters and broad sense heritabilities from this study could help in parental selection in breeding program of Thai oil palm.
