Influence of Mechanical Impedance on Rice Seedling Root Growth1

Abstract

AbstractThe influence of bulk density and the strength of lateritic sandy loam soil of Kharagpur on root growth of rice (Oryza saliva) seedlings was studied under controlled conditions. Rice (‘Taichung Native‐1’) seedlings were grown for 14 days in soils compacted to different bulk densities in painted galvanized iron cylinders. Water and nutrient requirements were met through nutrient solution.Maximum rice root growth and penetration occurred when the soil bulk density and penetration pressure were 1.6 g cm− 3 and 36 kg cm− 2, respectively. Lower bulk densities resulted in poor root growth, whereas subsequent increase in bulk densities above 1.6 g cm−3 decreased root growth. A penetration pressure of 72 kg cm− 2 was found to be critical for rice root penetration and growth. Rice root growth under saturated conditions is more significantly related to bulk density than to strength of the soil.