The Interaction of Irrigation Water Salinity, Vermicompost and Cultivar onGrowth, Yield and Yield Components of Canola

In order to investigate the interaction of irrigation water salinity (four levels including 1.15, 4.0, 7.0 and 10.0 dS.m-1) and vermicompost organic fertilizer (two levels including zero and 10 Tons.ha-1) and cultivar (including Hyola 4815, 308 and 401 and RGS) on growth, yield and yield components of canola, an experiment was designed as factorial based on complete randomized blocks with three replications in Gorgan region. Significant difference between four cultivars in term of days to flowering was in order of RGS˃401˃308˃4815. The interaction of salinity, vermicompost and cultivar on the days to maturity was significant. However, the significant reduction of this trait was observed by vermicompost (2.2 days) and salinity (1.9 days). Application of vermicompost increased the number of secondary branches by 52.2% averagely; however, this increase was higher in Hyola 401 cultivar. Vermicompost resulted reducion in the 1000-seeds weight and silique length of the studied cultivars, except for the Hyola 4815 and Hyola 401 which increased significantly. There was observed increasing stem diameter, seeds per silique, silique per plant, seed yield (from 1358.5 to 2067.1 Kg.ha-1) and biological yield (from 3603.2 to 5318.3 Kg.ha-1) under the influence of vermicompost by 40, 23, 70, 52, and 48%, respectively. Among the studied cultivars, Hyola 308 and RGS cultivers had the highest and lowest seed yield, with 1855.4 and 1572.8 Kg.ha-1, respectively. The higher ability of Hyola 308 in production of seed number per silique and siliques number per plant and Hyola 401 in seed number per silique and 1000-seeds weight resulted in their seed yield was significantly higher than Hyola 4815 and RGS. The interaction of vermicompost and salinity showed that increased salinity in the absence of vermicompost resulted in a significant increase in 1000-seeds weight and insignificant reduction in seed yield and biological yield but in vermicompost application condition, these effects were reverse.