Abstract: In order to understand the suitability of newly developed lines in the ecological area of the Yangtze river basin for machine harvesting,22 hybrids or lines of Brassica napus involved in the national regional trials of the upper Yangtze river reaches were assessed for pod shatter resistance using improved random impact test method. The results showed that pod shatter resistant index ranged from 0.05-0.76. The index of control variety Rongyou18 was 0.16,with a very low pod shatter resistance. The index of control variety Zhongshuang 11 was 0.61,with an intermediate resistance. 7 new hybrids or lines with higher average pod shatter resistance index were identified,including Fngpaiyou 555,Wanyou 26,Mianyou 21,Qingyou 8,Neiyou 835,Qianyou 31 and Dexinyou 97. Based on further analysis of other important agronomic traits of the 7 hybrids or lines with relatively high pod shatter resistance,4 hybrids,including Wanyou 26,Qingyou 8,Neiyou 835 and Qianyou 31,could be used for machine harvesting cultivation. The yield and other traits of these 4 varieties should be further evaluated.

Key words: Brassica napus L., pod shatter resistant index, variety screening