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 S1 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.