Effect of salinity and boron on seed germination and emergence of canola (Brassica napus L.)

Seed germination and the following growth of young seedlings are important stages of plant development particularly under stress conditions and plant survival depends on these two influential stages. The effects of salinity and boron on seed germination and seedling emergence of canola (Brassica napus L.) were examined in this research. Results showed that the seed germination were significantly (P≤0. 001) decreased and delay in seed germination increased by increasing the salinity. The percentage of germination in natural saline water was less than that of NaCl + CaCl2 solution when measured in high salinity levels. When using natural saline water، minimum germination was observed in 30 dS m-1 i. e.، 75% compared to control. Also، increased delay in germination was observed with increasing salinity levels; as delaying in germination at 30 dS m-1 (through application of NaCl + CaCl2 solution)، compared to non-saline conditions was nearly doubled. On the other hand، in the first and second experiments، boron application reduced germination significantly (P≤0. 001) and increased delay in germination. Combination of salinity and boron further reduced germination and caused more delay in germination. In the third experiment، the percentage of emerged plantlets decreased from 57% in the control to about two percent in salinity of 9 dS m-1. Inclusion of boron in soil significantly reduced emerging seed of canola. The results suggest when using saline waters، besides its osmotic effect، the boron concentration should also be considered.