Abstract:

The research aims to screen out the germplasm of Coix with high cold resistance, and provide a basis for hybrid breeding and cultivation of Coix. Taking 16 germplasms of Coix as test materials, we cultured the materials under low temperature stress at 3℃ for 3 days, measured the physiological indexes related to cold resistance, and comprehensively evaluated cold resistance by using a pole-sorting method. The results showed that under low temperature (3℃) stress, the chlorophyll content and SOD activity of leaves decreased, and the electrical conductivity content, malondialdehyde content, soluble sugar content, proline content, and soluble protein content of leaves of various germplasms increased to varying degrees. Under the treatment of low temperature and normal temperature, there were obvious differences in the change of these physiological indicators, indicating that the changes are closely related to the cold resistance of the Coix. The rank of the cold resistance of the Coix obtained by the pole-sorting method is: ‘Yunye-6’<‘YGL’<‘Yunye-10’<‘Yunye-8’<‘Yunye-12’<‘Yunye-1’<‘Yunye-4’<‘Yunye-3’<‘Yunye-5’<‘YLO’<‘YOL-12’<‘Yunye-7’<‘Yunye-9’<‘Yunye-11’<‘Yunye-2’<‘Y9-5’. Among the 16 germplasms, ‘Y9-5’ and ‘Yunye-2’could be used as cold resistance material for hybrid breeding and cultivation.

Key words: Coix, cold tolerance, physiological indexes, pole-sorting method, comprehensive evaluation