许多作者报道过,与生长速率及产量潜力有关的杂种优势可能与 F_1杂种植株内的生理生化活性较高有关。作者在一系列试验中曾指出,诸如玉米 F_1发芽较快以及幼苗生长较健壮等杂种优势都与胚内的 RNA、蛋白质和 DNA的高代谢活性有关。另一方面,玉米胚组织内所贮存的脂类和蛋白质及胚乳中的淀粉,对维持发芽籽粒中的胚轴生长起着重要作用。 Many authors have reported that the heterosis associated with the growth rate and yield potential may be related to the higher physiological and biochemical activities in F1 hybrid plants. In a series of experiments, the authors pointed out that hybrids such as rapid F_1 maize F_1 growth and robust seedling growth are all associated with the high metabolic activity of RNA, protein and DNA in embryos. On the other hand, the lipid and protein stored in the maize embryo tissue and the starch in the endosperm play an important role in maintaining the hypocotyl in the germinating grain.