Grain Sorghum Response to Row Spacing, Plant Density, and Planter Skips

Abstract

Adverse weather and soil conditions may prevent grain sorghum (Sorghum bicolor L. Moench) growers from achieving an evenly spaced, optimum plant density. In these situations, growers must decide whether to replant or manage a grain sorghum crop with uneven and/or lower stands. Research indicated that grain sorghum grain yield response to row spacing was variable and dependent upon environment. In uniform stands, grain sorghum was able to partially compensate for densities below 60,000 plants per acre by producing additional grain heads per plant. Results also indicated that in uniform grain sorghum stands, N at 100 to 150 lb/acre produced the highest grain yield under both high and low plant density conditions. In non‐uniform stands with frequent 6‐ to 9‐ft skips, sorghum had significantly reduced grain yield when compared to a uniform stand or 3‐ft skips. These results do not support reduced N rates in either uniform or uneven grain sorghum stands with less than optimal plant densities.

Quality Protein Maize Response to Nitrogen Rate and Plant Density in the Guinea Savanna Zone of Ghana

“…Eghball & Maranville (1993) found that the mean N influx of maize increased with increasing soil N supply. The increased yield with N application is supported by the findings of others who reported increases in grain yields of cereals with N application (Buah et al, 1998;Khosla et al, 2000;Workayehu, 2000;Yamoah et al, 2002;Aflakpui et al, 2005b;Conley et al, 2005). The effect of N fertilizer application in improving soil fertility status and sustainable crop production is demonstrated in the increased grain yield recorded in this study.…”

“…From this study, the contribution of plant population to grain yield was minimal (4.2%). These results differ from findings in other regions, where grain yield increased as plant density was increased (von Qualen et al, 1993;LaFarge & Hammer 2002;Conley et al, 2005), but supported by the findings of others (Ma et al, 2003;Aflakpui et al, 2005b). The results suggest that hybrid maize was somewhat flexible to plant density and replanting may not be necessary in some situations.…”

“…Research has demonstrated the importance of inorganic fertilizer in crop production (Buah et al, 1998;Workayehu, 2000;Yamoah et al, 2002;Aflakpui et al, 2005b;Conley et al, 2005). Response to fertilizer is dependent on amount and distributions of moisture, soil fertility and variety.…”

“…The relationship between plant density and yield of cereals has been studied extensively, but conflicting reports have led to a renewed interest in the effects of high plant densities on yield of cereals (Workayehu 2000;Ma et al, 2003). Conley et al (2005) showed that crop yield response to row spacing was variable and dependent upon environment. High plant densities increased cereal crop yield when compared to the recommended plant density in some studies (von Qualen et al, 1993;LaFarge & Hammer, 2002;Conley et al, 2005).…”

“…Conley et al (2005) showed that crop yield response to row spacing was variable and dependent upon environment. High plant densities increased cereal crop yield when compared to the recommended plant density in some studies (von Qualen et al, 1993;LaFarge & Hammer, 2002;Conley et al, 2005). Other researchers found that plant density had no effect on maize grain yield (Ma et al, 2003;Aflakui et al, 2005b;Shapiro & Wortmann, 2006).…”