Use of Alpha-Designs in Oil Palm Breeding Trials

摘要

In Oil Palm Breeding trials the plots have palms at vertices of equilateral triangles with side length of 9 m. The plots consist of 6×6 = 36 palms, hence a plot is a rectangle of 46.8 × 54m. The number of tested varieties is 20 - 40, the experimental design needed is an incomplete block design, with usually 3 replications; the alpha-designs can give a connected incomplete block design. Current Oil Palm planting materials are DxP hybrid based on crossing selected dura palms (female parents) with pisifera palms (male parents) to produce tenera palms with thin shelled fruits. The crossing scheme of A dura and B pisifera is an incomplete diallel if he number of crossings C is smaller than A*B. To make a connected crossing scheme the alpha-design can be used. In the analysis of an oil palm breeding trial an additive model of the dura and pisifera effects is applied to estimate the general combining ability of the parents after removing the fixed replication effect and the random blocks within the replication effects. The analysis can be done with the package SAS or IBM SPSS Statistics with program Mixed; further with R and the R package lme4.