Study on Yield Formation of Winter Wheat Cultivars with Different Spike Types and Their Key Cultivation Techniques for Super-high Yield

The study was carried out on yield formation of winter wheat with different spike types in Yanshi,Henan province from 1997 to 1999.The results indicated that differences in population dynamic,development of spike and floret,and grain filling existed between small and large spike wheat cultivars.With regards to high ratio of spikes to tillers and low ear weight in small-spike cultivars,nitrogen application at jointing stage increased grain number by decreasing aborted florets or ovaries.As for large-spike cultivars,low ratio of spikes to tillers and insufficient spike number in the field resulted in low yield compared with small-spike cultivars,which suggested that increasing sowing rate reasonably could get more spikes and higher yield.