Evaluation of the growth and heterosis of hybrids among three commercially important sea urchins in China: Strongylocentrotus nudus, S. intermedius and Anthocidaris crassispina

After 22 months of lab culturing, we measured the growth characteristics (i.e., diameter, height, wet body weight and gonad weight) and evaluated heterosis. The Si × Ac group showed clear heterosis in all characteristics compared to conspecific controls (4.00-59.40%). The Si × Sn and Ac × Sn groups showed limited heterosis, and the hybrids produced few or no gametes. The heterosis of Si × Ac, Si × Sn and Ac × Sn obtained in this work will have significant implications for the development of sea urchin aquaculture.