Study on winter wheat yield under technology of no-tillage, bunch-planting, whole film and soil mulching during whole growth.

The new cultural technology is the characteristic of covering with film on which covering soil; no tillage and bunch planting during the whole growth period. In order to make clean its mechanism of improving yield and the other important factors, we designed the test of 4 factors with 4 levels and repeated 4 times under the different densities. The results show the technology, compared with traditional culture, is able to put off the date of sowing but advance time of reviving green and ripening, increase the rate of healthy seedlings before over wintering, and also produce positive to the agronomic traits. It can improve yield, compared with CK, by a large percent of 22.79%-34.73%, that is, increase by 1304.11 kg/hm2-1715.16 kg/hm2. The highest yield under the density of 10 seeds per hole is 7055.10 kg/hm2, which owns to many factors, especially population, effective tillers, effective spikelets, number of grain per ear and volumetric weight. With the different density, the technology produces different efficiency on the traits and yield factors. The density of range 8～10 seeds per hole is able to develop latent yield capacity, improve relative factors' productive ability, prevent crop lodging, ensure enough fertilizer and avoid premature decay in the late stage. If less than the range, it always leads to less population and production reduction. If more than the range, the lodging, less fertilizer, premature decay and nutrient partial consumption would be the results. Conclusion: the new technology is adapt to the dried and semidried area of 500mm rainfall, able to accumulate invalid rainfall, upgrade deeper water, improve water use efficiency, increase surface temperature during early growth stage and decrease in late stage. It also can do its best to develop cultivars production potentiality, provide excellent conditions to wheat growth and is helpful to every living factor, which is beneficial to highly yield.