Prediction of the heterosis of Laminaria hybrids with the genetic distance between their parental gametophyte clones

Eighteen microsatellite markers were used to determine the genetic distances between the parental gametophyte clones of 14 Laminaria hybrids, which were then used to establish a linear relationship with the heterosis (hybrid vigor) of economic traits including yield, mean blade try weight, mean blade fresh weight, blade length, blade width and mean blade thickness using regression analysis. Significant regression was found between the genetic distance (x) and the heterosis (y) of yield (y=115.10 x 77.97, r=0.8151, p=0.00038), mean blade dry weight (y=115.23 x 77.97, r=0.8154, p=0.00038), mean blade fresh weight (y=100.08 x 57.85, r=0.7306, p=0.0030) and blade length (y=204.11 x 46.77, r=0.6963, p=0.00566). The prediction of the heterosis of Laminaria hybrids with the genetic distance between parental gametophyte clones will facilitate the selection of elite Laminaria hybrids by avoiding the time-consuming and labor-intensive trait evaluation of a large number of hybridization combinations.