| Food security is a guarantee to the stable development of the country.In recent years, due to the rapid growth of population, the global demand for food is increasing.Wheat isthe largest and most widely distributed grain crops in the world, so for the food security and economic stability it is very important to keep wheat industry developing he althily. At present,winter wheat is the main cultivate wheatin China, and Heilongjiang province has always been the main producing area of wheat,but the latitude of Heilongjiang province is higher than other areaswith long duration of winter,low and severe fluctuation temperature and other unfavorable factors. Therefore, Improving the cold resistance of winter wheat and exploringto plant high potentialyield of winter wheat with large area in high latitude frigid regions have become a new research area that challenges to increase the total yield of the wheat.The winter wheat has a complicated cold resistance mechanism and the climate conditions of cold temperate zone in China are complex and changeable, so they bring a great threat to winter wheat to live thr ough the winter safely. Now, a newseries of winter wheat varieties that can live through the winter safely in frigid regions has been bred, and “Dongnong dongmia1†is a representative one, so how to breed higher yield and more adaptable varieties of winter wheat that live through the winter safely in the frigid areas has become a long-term task in the future.In this experiment 12 varities of winter wheat were chosen as materials, for instance,Dongnong dongmai1,Dongnong 03-608,Dongnong 03-614,which could live through the winter safely in Heilongjiang province. Two factorsthat are variety and densityrandomized block experiment was used. The relationship between the population uniformity and yield, yield traits and agronomic traits were studied.The genetic effects of yield traits, agronomic traits and population uniformity of winter wheat were revealed.The validity of the new index in the process of new variety selection in winter wheat were discussed. Provided theoretical basis for high yield and high efficiency breeding of Winter Wheat in frigid region The results of this experiment were as followings:1. Spike number, harvest index, thousand kerner weight,total spike numbers, and effective spike numbers all had significant correlations with yield. harvest index, and thousand kerner weight had a great influence on yield. These traits had a great contribution to yield, and the contribution rate was 71.80%.the contribution rate of spike number and stem length was 54.27%.2. The population uniformityincrease of spike length and kernels per spike could improve the yield, kernels per spike and spike length. Heritability of spike length uniformity and kernels per spike uniformity was relatively low, respectively 23.78%,4.35%. It should not be used as the basis for selection in the early generation, but it the could be selected spike length uniformity and kernels per spike uniformity of winter wheat stability generation under strict condition..3. Increasing the uniformity of morphological characters was beneficial to the incr ease of spike length,total spike number,effective spike number and kernels per spike..4. The uniformity of stem length,spike length,effective spike number, and kernels per spike were all at high levels, and to some extent they had a positive role in spike l ength, effective spike number,kernels per spike and thousand kernels weight, and they were beneficial to reducing the invalidnumber of spike and increasing yield... |
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