棉花品种间的杂交后代在产量和品质等方面一般都具有杂种优势。随着育种水平的提高,新品种与杂交种之间的差距逐渐缩短,也就是杂交种与品种的竞争优势在缩小。如何进一步提高杂交种的竞争优势是值 Hybrids between cotton cultivars generally have heterosis in terms of yield and quality. With the improvement of breeding level, the gap between new varieties and hybrids is gradually shortened, that is, the competitive advantages of hybrids and varieties are narrowing. How to further improve the competitive advantage of hybrids is the value