Simulation test of hybrid rice production demonstrated that the purity of hybrid rice would be improved greatly by using leaf colour as a marker to eliminate the false hybrid rice at early stage.
模拟杂交稻生产和制种繁种，表明利用苗期叶色标记结合人工去杂，可有效提高田间纯度。
3
The first group had their plumage colour enhanced with a marker pen.