分枝型普通小麦的创育及其杂种优势利用研究

Study on the Development and the Heterosis of Branched Heads in Common Wheat

小麦产量构成的三要素是单位面积穗数、每穗粒数及粒重，其中通过增加穗粒数来提高产量的潜力是很大的。应用亚远缘梯级复合杂交培育出多粒穗分枝普通小麦（2n=42）品系，其优点是半矮秆，抗病抗逆性好。分枝性状稳定，穗粒数较普通小麦增加50％以上，在良好栽培条件下，公顷产量最高可达11235奴。选用其中两个不同类型的分枝小麦与5个普通小麦配置了6个CHA杂交组合，试验结果表明，其中杂种比双亲之一的推广品种晋麦67号（CK）等平均增产24．4％，幅度为7．5％-38．8％。由此可以预测，多粒穗分枝小麦将成为CHA组合理想的强优势亲本，并在生产中得以广泛应用。

The most important yield components in wheat are panicles per unit area, number of spikelets per panicle and spikelet weight. We can increase the number of spikelets per panicle which is considered to be the most effective approach to improve the yield. We breed the branched heads wheat varieties （2n = 42） through the method of sub - distant compound crossing which have several advantages ： semi - dwarf plant, plant resistance and plant diseases resistance . The characteristic of branched heads is stable. There is a 50 percent increase in the number of spikelets per panicle. The highest yields of branched heads wheat can reach i 1 235 kilogram when they are in suitable - breeding conditions. We select two different varieties of branched heads wheat and five common wheat in order to get 6 CHA cross. The experiment illustrates that whatever crossing or back - crossing the average superiority is 24.4 percent which means that the later generations exceed their parents （Jin Chun 67 and so forth） in the percentage of 24.4. This figure varies in the range of 7.5 percent to 38.8 percent. To sum up, we can predict that branched heads in wheat will be used widely as the ideal parent of CHA cross which have powerful superiority.