Radial tires give better traction.
Their advantage is greater in tougher conditions such as higher drawbar loads and softer soils. Lower air pressures are better. Radial tires are designed to perform best at their lowest recommended air pressure for the load. You'll need to refer to tire inflation charts in your tractor's operator's manual for the recommended inflation for your tractor weight and tire size. Recommended inflation levels may be as low as 6 to 8 psi.