Effects of waterlogging followed by a salinity peak on rapeseed (Brassica napus L)

Due mainly to alterations in plant metabolism, lack of oxygen and excess salts are disturbances that affect crop yields. In different parts of the world crops are subjected to those disturbances, simultaneously or successively. Our objective was to determine the effects of a winter waterlogging followed by a spring salt peak on rapeseed yield. A pot experiment, combining waterlogging and salinization was carried out. The waterlogging duration was: 0 (control), 3, 7 and 14 days and the salinity treatments were peaks of Electrical Conductivity of 5 and 8 dS m(-1) and the control. The yield started decreasing from 3 days during waterlogging, mainly due to the lower number of seeds per plant. The salt peak from 5 dS m(-1) affected the yield only in plants which had suffered a waterlogging lower than 7 days, showing interaction between salinity and waterlogging. Only salinity reduced oil content. The saline peak affected the K, Ca and Na concentration in plant tissues, but the effect of salinity on rapeseed could be more related to soil water potential than specific ion toxicities or imbalance.