Evaluation of Seed Yield of Three Brassica Species, B. napus, B. rapa and

Canola is one of the most important oilseed crops. Seeds of canola contain 40-50% oil and 22% protein. In the present study seed yields of 15 lines of three brassica species, B. napus, B. rapa and B. juncea were evaluated under warm dryland conditions in Gachsaran Agricultural Research Station during three cropping seasons (2003-2006) using a randomized complete block design. Each line was planted in six rows with four meter length and 25cm distance from each other. Different agronomic traits were recorded during the growth period of canola. The simple and combined analusis of variance on data showed that lines different significantly for different traits such as days to flowering, plant height, seeds per pod, days to maturity, seed yield and 1000 seeds weight indicating genetic variations among the lines. Results of combined analysis of variance indicated that the effects of line and years were significant at 1% level for all traits, but the effects of line×year was not significant for plant height. In 2003-2004 and 2004-2005 cropping seasons, line Lethbridge from B. juncea with 1.018 and 1.466 (tha-1) respectively, produced the highest seed yield, while in 2005-2006 cropping season the seed yield of line J-98 from the same species was 3.194 tha-1.