Analysis of the genetic effects for several traits in oil palm (Elaeis guineensis Jacq.) populations. I. Population means

Abstract

An oil palm experiment was set up in the Ivory Coast to compare the effects of crossing and selfing within two origins, Deli and La Mé, on the mean and the variability of Deli x Mé between-origin hybrids. The originality of the experiment lay in the crossing plan, which provided access to genetic parameters related to additivity, dominance and different components of epistasis. This first part covers the analysis of the components of the mean. The parents used were obtained from four palms, two from each origin. Those of La Mé origin were half-sibs. The common parent came from a wild stand in the Ivory Coast. Those of Deli origin were from two different populations bred in Southeast Asia for several generations from a narrow genetic base. These four parents gave rise to nine Deli x La Mé hybrid populations with double-cousintype links. The additive component is more important within the Deli origin than within the La Mé origin. This may be explained by the large genetic divergence between the two Deli parent palms. On the other hand, the additive(*) additive epistasis is more substantial within the La Mé origin, probably because of inbreeding. The discussion concentrates on how this information should be used when choosing parents to be crossed and tested and to produce improved populations. The crossing plan proposed can be of general use and is suitable for other species in a reciprocal recurrent selection programme.

Ecology and Evolutionary Biology of Clonal Plants

“…In self-compatible species, mating among ramets of the same genet will cause a significant portion of the non-additive effect on a trait to be passed on to seed offspring because it results in reduced breakup of allelic combinations (Baudouin et at., 1995;Pollack and Sabran, 1999). The inherently spatial nature of clonal growth may cause ramets of a resistant genet to be clumped within a population, which is likely to increase the frequency of matings among ramets of the same genet (Silander, 1985b, Charpantier, pp.…”

Components of variation of polygenic systems with digenic epistasis

“…In a theoretical work on the analysis of the genetic effects of several oil palm traits, Baudouin et al (1995) concluded that "Epistasis effects may contribute substantially to population means if the material tested is highly heterozygous, the genetic base is narrow (selected material or few individuals used) or there is linkage disequilibrium (due to further selection and insufficient intercrossing generations. )", although in the papers published by Balatero et al (1995), Gingera et al (1995) and Holtom et al (1995) there was no evidence of epistasis.…”