Genetic analysis of cut-flower longevity in Antirrhinum majus

Genetics of Antirrhinum majus L. (snapdragon) cut flower postharvest longev ity (PHL) was investigated by generation means analysis using a white short -lived inbred (WS) and white long-lived inbred (WL) to determine mode of in heritance and heritability. Broad and narrow sense PHL heritability was est imated at 78 % and 30%, respectively Scaling tests for adequacy of an addit ive-dominance model in explaining PHL inheritance suggested absence of epis tasis. However, joint scaling indicated digenic or higher order epistatic i nteractions. Fitting of a digenic epistatic model revealed significant addi tive effects and nonsignificant dominance and epistatic interactions. Addit ionally, based on sequential model fittings all six parameters [mean,additi ve(a), dominance(d),a x a,d x d,and a x d] proved necessary to explain obse rved PHL variation. Continuous variation for PHL observed in the F-2 and ba ckcross generations suggests PHL is quantitative. Assessment of associated traits revealed a positive relationship between number of flowers opening p ostharvest on a cut newer and PHL, In addition, floret wilting led to short PHL while floret browning was associated with long PHL.