Germination and Early Seedling Development under Low Temperature in Canola
- Cory L. Nykiforuk and
- Anne M. Johnson-Flanagan
Canola is seeded when ambient temperatures are below the optimum. Therefore, we wished to determine whether certified seedlots displayed variation in low temperature germination potential and, thereafter, to study the effects of low temperature during germination and early seedling development. Canola (Brassiea napus L. cv. Westar) seed was tested for germination potential at 22, 10, 6, and 2 °C. Two seedlots, designated L and H, which represented the extremes in germination potential at 10 °C, were chosen for further study. Under the optimal conditions of 22 °C the two seedlots exhibited similar germination rates and early seedling growth. At 10 °C, L reached 95% germination within 8 d and displayed rapid seedling growth. This was associated with high isocitrate lyase activities and rapid mobilization of total lipid and protein reserves. Seedlot H, at 10 °C, did not reach a high percentage of germination until Day 12, and seedling growth was slow relative to that of L. Seedlot H had more gradual increases in isocitrate lyase activity, mobidization of storage lipid, and protein mobilization at 10 °C. Both seedlots germinated poorly at 6 and 2 °C. At 6 °C, L displayed higher isocitrate lyase activity and higher rates of lipid and protein mobilization than H. From these studies we have determined that low temperature has a deleterious effect on the germination of canola and this may be reflected in a loss or a delay of coordination in the mobilization of reserves. In addition, differences within the Westar cultivar exist with respect to germination under low temperature.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 1994.