Six field experiments were conducted in Arkansas during the 2004 crop season at three locations to evaluate effect of plant population and hybrid on grain sorghum yield. Three experiments were conducted under irrigated conditions and three were grown in a dryland production system. Three popular high yielding hybrids were evaluated at six plant populations (20, 40, 60, 80, 100, and 120 thousand plants/acre) to evaluate at what plant population maximum grain yields would occur. Standard weed control practices were utilized and supplemental fertilizer was applied according to soil test guidelines. Row spacing was 38 inches in 4 experiments and 30 inches in two experiments. Plots were harvested with a small plot combine at maturity and yields were adjusted to 14% moisture. Grain sorghum yields were maximized with plant populations of approximately 60,000 plants/acre, but populations of 120,000/acre did not decrease yields under irrigated conditions. Under dryland conditions, yields tended to be maximized by populations of approximately 50,000 plants/acre.
Two field experiments were conducted to evaluate the effect of starter fertilizer on grain sorghum yield. Ten popular grain sorghum hybrids were evaluated with or without starter fertilizer placed in the seed furrow at two locations. Starter fertilizer consisted of 30 lbs of 18-46-0. During the growing season no effect on plant growth was seen from starter fertilizer and yields were not affected by starter fertilizer.
See more of Crops Posters/Reception
See more of The ASA Southern Regional Branch (June 19-21, 2005)