Our key target is to produce hybrid rice with consistently high - yield heterosis (hybrid vigor), good grain quality, tolerance to key environmental stresses, multiple resistances to insect pests and diseases, and high seed production yield. (irri.org)
They refer to this as the «Hybrid Vigor» caused by the «Heterosis Effect». (bulldogmixes.com)
Heterosis applies for the first generation — but where do you go from there? (americanshihtzuclub.org)