Production of Oilseed Crops on Marginal Land: Drought and Salt Tolerance of Selected Oilseed Crops During Germination Stage

The use of marginal land (saline soils and saline water) for producing biofuel feedstocks will help reduce energy dependence on foreign oils, while minimizing the direct competition with food production.  To be grown successfully in marginal land, bioenergy crops must be tolerant to drought and salt stresses.  The objective of this study was to evaluate the drought and salt tolerance of selected oilseed crops during germination stage.  A total of 9 treatments (solutions) were created, a control (distilled water, DI), four drought levels of -0.30, -0.58, -0.80, -1.05 MPa, which were equivalent in osmotic potential to the four salt stress levels of 50, 100, 150, 200 mM NaCl.  Drought and salt stresses were created by adding PEG (Polyethylene) and NaCl to DI water, respectively.  Twenty seeds of two genotypes of canola DKW 47-15 and DKW 45-10, three genotypes of camelina Cheyenne spring, BSX-WG1, and BSX-WG3, and three genotypes of safflower CW 1221, CW-99-OL, and PI 406002 were sown in Petri dishes containing a filter paper wetted with respective treatment solutions. Genotype and treatment interactively affected germination for canola and camelina. For safflower, germination rates differed among genotypes and was affected by treatments, but no interaction between genotype and treatment was observed. Treatment and genotype interactively affected the radical and hypocotyls elongation of camelina and safflower. For canola, high drought and salt stresses reduced radical and hypocotyls elongation.  Results indicated different responses to drought and salt stresses among genotypes of all three crops. Further studies are needed to evaluate the tolerance to drought and salt stresses during seedling emergence and early growth stages for potentially tolerant genotypes.