Genetic analysis of inbreeding depression in plus tree 850.55 of Pinus radiata D. Don.: I.: Genetic map with distorted markers

A genetic map of Pinus radiata plus tree 850.55 was constructed using megagametophytes of S-1 seeds. The map contained 19 linkage groups, with 168 RAPD and four microsatellite markers. The total map length was 1116.7 cM (Kosambi's function) and was estimated to cover 56% of the genome. Of the 172 markers, 59 (34%) were distorted from the expected 1:1 ratio in megagametophytes (P < 0.05). We show that if the distortion is caused by a single viability gene or by sampling error, the estimate of recombination frequency in megagametophytes of selfed seeds would not be affected.