To comprehensively assess and recommend the optimum seeding date of no-till rapeseed in low altitude mountain areas, comparisons of no-till rapeseed agronomic traits and yield of 10 seeding dates in 4 altitude areas were carried out from 2011 to 2015 in Yuxi by using grey relation analysis and fuzzy clustering analysis. The results indicated that: (1) there was significant difference of main agronomic traits among different seeding dates, the main agronomic traits of rapeseed of earlier seeding date were better than that of conventional seeding date (October 10); (2) the correlation between yield and main agronomic traits varied in different degrees; (3) the yield of different seeding dates varied in different degrees; (4) the optimum seeding date of no-till rapeseed depended on climate, the best seeding date in warm year was around August 10 -September 10, whereas in cold year it was around August 30 - September 30. Therefore, according to the comprehensive evaluation of the yielding ability and stability of rapeseed of 10 seeding dates during 5 years, the optimum seeding date of August 30 - September 10 is recommended for no-till rapeseed in low altitude mountain areas.
Oil Crops
