Allelopathic effect of canola residues on germination and growth of corn

In order to study allelopathic effect of canola residues on growth of corn two greenhouse and laboratory experiments were conducted. The design of experiment was randomized complete block design in factorial with 12 treatments and four replications. The treatments were residues in four levels (0, 0.07, 0.09, and 0.11) and time of residues maintenance in three levels (planting at the same time mixing residues with soil, 15, and 30 days afterwarth. The laboratory experiment based on randomized completely design with four replications. The treatments were four concentrations extract (0, 5%, 10%, and 15%) of canola residues. The reasults showed in first week that planting at the same time mixing residues with soil deacreased stem length (2.05- 3,43 cm), root length (6.35-8.03 cm), root dry weight (0,15, 0,23 gr), stem dry weight (0.03 gr), root/stem dry weight ratio (0.63,1.11units), In the second week decreased stem length (4.3 cm), root dry weight(0.15-0.19 gr), stem dry weight (0.079-0.102gr), in the third week decreased stem length (5.32-7.89 cm), stem dry weight (3.07, 4.93gr), root volume (0.3 cm3), root/stem dry weight ratio (0.23unit), in forth week decreased root length (11.56-13.38 cm), root volume (4.36-6.01cm3), stem dry weight (0.75gr), root/stem dry weight ratio(0.29-0.37 units). The effect of residues was notsignificant. So the interaction between planting date and residues in all four week was not-significant. Results of laboratory experiment showed that effect of canola extracts on germination and the time to 50% germination was significant.