Effects of Seeding Date, Seeding Rate and Nitrogen Rate on Yield and Agronomic Characters of Direct - seeding Rape Dadi 95

【Objective】The suitable seeding date, seeding rate and nitrogen rate of direct - seeding rape Dadi 95 were determined in order to provide technical guidance for its cultivation and promotion. 【Method】The growth process and agronomic characters of Dadi 95 were investigated under different seeding date, seeding rate and nitrogen rate combinations by using split plot design.【Result】The growth process of rape was mainly affected by seeding date. Under the same seeding date with different seeding rates and fertilization amounts, there was no obvious effect on the growth process of rape. The differences of plant height, branch position, branch number, length of main inflorescence, pod number of main inflorescence, pod spacing, pod number per plant, pod length, yield per plant and plot yield reached an extremely significant level in different seeding date treatments. The differences of plant height, branch position and branch number reached an extremely significant level under different seeding rates. Seeding date had the greatest impact on the yield. Early seeding could increase the yield of rape. The plot yield was positively correlated with the main sequence length, the pod number per plant and the yield per plant, but negatively correlated with the pod spacing.【Conclusion】When seeding on April 12, with seeding rate and urea amount set as 0.75 kg and 15 kg/667m2 respectively, the yield of rape was the highest, which was 38.64% higher than the average. For early seeding of spring rape, proper increase of seeding and fertilization rates could effectively increased the yield of rape. For late seeding of spring rape, low-density and high-level fertilization could make the plant grow vigorously, but it was not conducive to the development of group yield, and proper increase of density could ensure the overall yield.