Sign up for email alerts of new Fluid Journal issues!
Fluid Journal : Fluid Journal 1999-2001
Summer 1999 Summary: Knifing produced higher yields than broadcast or dribble applications. Even though knifing tended to increase yields in all tillage systems, placement was more important in the no- till system. Knifing increased amounts and rates of N, P, and K uptakes early in the season and appeared to shorten the time to reach maximum plant growth and P and K uptakes. Positional availability of knifed plant nutrients early in the growing season, especially P and K, may improve nutrient uptake by grain sorghum and also affect kernel potential that is determined shortly after growing point differentiation and, consequently, yield. _________________________________ Public awareness for the environ- ment, farm programs, and economic concerns has increased the amount of U.S. land planted in conservation tillage. With less soil mixing, placement of fertilizer becomes more important. Research has shown that fertilizer placement can affect yields in conservation tillage systems. Surface or subsurface banding has resulted in greater nutrient-use efficiency than broadcast application. The objective of this two-year study was to determine the effect of broadcast, surface band (dribble), and subsurface band (knife) placements of N, P, and K suspensions on grain sorghum yield, dry matter production and nutrient uptake in conservation tillage systems. Yield components Tillage. Grain sorghum yield was not significantly affected by tillage system in either year. Placement. Suspension fertilizer applications increased two-year average yields over the check by nearly 20 bu/A, regardless of placement method (Figure 1). Method of placement also signifi- cantly affected yields. Knifing produced higher yields than broadcast or dribble applications. Even though knifing tended to increase yields in all tillage systems, placement was more important in the no-till system. Split N applications did not increase yields. However, in the first year of the study, a knife/split-N application tended to result in the highest yields (data not shown). Kernels per head were affected by suspension application methods (Figure 2) and paralleled yield responses. These data suggest that placement methods affected the sorghum plants early in the growing season because the potential number of kernels per head is determined shortly after growing point differentiation. Plant stand was minimally affected by placement, as also shown in Figure 2. Growth and uptake Tillage. Although no-till resulted in nearly a 30 percent decrease in dry matter accumulation and N, P, and K uptakes at the nine-leaf growth stage when compared with either reduced or ridge-till, further reductions at later growth stages were generally not Dr. Dan Sweeney Nutrient Placement Affects Yield In Grain Sorghum Kansas scientist compares sorghum responses to broadcast, dribble, and knifing of NPK suspension fertilizers in two-year placement study.
Fluid Journal 1996-1998
Fluid Journal 2002-2004