effect of tillage systems and organic manure on root morphology of corn

abstract methods of tillage and organic matter affect root growth and distribution and therefore nutrient uptake by plant and its growth. this study was performed consecutive two years. tillage treatments included disk harrowing + two disk harrowings as reduced tillage (15 cm plowing depth) and moldboard plowing + two disk harrowings as conventional tillage system (30 cm plowing depth). also, three levels of 0, 30 and 60 tons per hectare farmyard manure were used as organic manure treatments. the above mentioned treatments were done in a split block design with 3 replications and under corn cultivation for two years. to determination of root morphological properties of plant, sampling was done by a cylinder with a cap from top of the row and root length and density were measured. the results showed, tillage systems had a significant effect (p=0.05) on root length and density of corn in 0-20 cm soil depth. in the reduced tillage treatment, root length and density in the stages of 9 and 11 leaves increased significantly in comparison conventional tillage, but root depth was higher at conventional tillage than reduced tillage. this is due to presence of soft soil (disturbed soil) in lower soil depth from top of the row under conventional tillage. the results indicated that manure had no significant effect on morphological root characteristics, but increased biological yield of corn.