Study on Yield Formation of Two Kinds of Spike of Winter Wheat Cultivars and Their Key Cultivation Techniques for Super-high Yield

It showed that differences in dynamic of population, development of spike and floret, and grain filling existed between two kinds of wheat cultivars in this paper. With regards to high ratio of spike to tiller and low ear weight in small-spike cultivars, nitrogen application at jointing stage increased grain number by decreasing aborted florets and ovaries. As for large-spike cultivars, low ratio of spike to tiller and insufficient spike number in the field resulted in low yield compared with small-spike cultivars, which are suggested that increasing sowing density, application of fertilizers and irrigation in fitted stage , increasing number of effective spike, reasonably could get more spikes and higher yield.