Screening Suitable Rapeseed Varieties In Brassica Napus L. For Mechanized Harvesting

In order to screen suitable rapeseed varieties for mechanized harvesting,in this paper theplant characters of6rape cultivars (including Yu10、Qinyan211、Za95、Zayou158、Shana oil15and QinyouNo.7) planted in the field with3kinds of densities (2×10~4/667m~2,3×10~4/667m~2,4×10~4/667m~2) and2sowing dates (September25th and October1st) wereinvestigated. The rapeseed variety suitable for mechanized harvesting was screenedpreliminarily via analyzing the agronomic traits、lodging resistance、disease resistance andflowering concentration of the6cultivars. All the materials’ pod crack angle character wasanalyzed through the random collision method to study the effects of planting density andsowing date on silique shatter resistance; A new designed measuring instrument was used tomeasure the silique shatter resistance, and evaluate the feasibility of the new instrumentcompared to random collision method. The results are as follows:Comprehensive analysis showed that the variety hybrid Zayou158was suitable formechanized harvesting. Hybrid Zayou158had lower plant height with the average height155cm, compact plant type, resistance to high planting density, slender stem, relativelyconcentrated flowering time, early maturity, the maturity’s consistency of pods is higher inlower and upper branches,8branches or so which positioned at about55cm, lodgingresistance and strong disease resistance. Although silique shatter resistance is relatively low,but very stable and not sensitive to changes of environmental. in the density of4×10~4plant/667m~2,the yield is higher;Planting density has significant effects on the silique shatter resistance of pods ofHybrid Qinyou No.7、Yu10and Qinyan211, among the6varieties. These effects mainlycaused the changes of the plant and pod characteristics under different planting density. Therape cultivars which had the longer Pod, the more thick skin and the wider fruit body hadstronger silique shatter resistance; The silique shatter resistance of hybrid158, za95andShaan oil15are stable, which have no significant change in the density, and suggesting that these varieties of pod silique shatter resistance capacity is relatively stable, not sensitive tothe change of the environment.Using the new design of the pod instrument determine the silique shatter resistance ofPods. Compared the result to the random collision method, we find that: the results have acertain consistency between new method of processing and random collision method.the newmethod can only be used to make a rough comparison of the silique shatter resistancedifference among different varieties. It cannot reflect the silique shatter resistance index of asingle pod accurately and only applies to the varieties that have stronger crack resistanceability.