Planting Soybean With A Grain Drill Inconsistently Increases Yield And Profit

Abstract

Growers can plant soybean [Glycine max (L.) Merr.] with a grain drill or row crop planter, which can affect seed and weed control costs and yield. Farmers planted soybean with a drill in 0.19‐m rows and row crop planter in 0.38‐ and 0.76‐m rows at two seeding rates (420,000 and 321,000 seeds ha−1) in two field‐scale studies in New York to obtain agronomic information and conduct partial budget analyses to aid in future planter selection and purchase decisions. Soybean intercepted more light at flowering in 0.19 (65–70%) compared with 0.76‐m rows (50–55%), despite lower early plant establishment (∼70 and ∼85%, respectively) at both locations. At a no‐till location, 0.76‐m rows compared with narrower rows had greater weed density at full pod stage (19.7 vs. 6.3 and 5.1 weeds m−2) and weed biomass at harvest (13.7 vs. 6.6 and 7.3 g m−2, respectively) but similar yield (∼3.30 Mg ha−1). At a chisel tillage location, soybean in 0.19‐m rows at the recommended 420,000 seeds ha−1 yielded 4% more (4.27 Mg ha−1) than in 0.76‐m rows at the recommended 321,000 seeds ha−1 (4.11 Mg ha−1). Partial budget analyses indicated that soybean in 0.19‐m rows at 420,000 seeds ha−1 had ∼$30 ha−1 greater profit compared with 0.76‐m rows at 321,000 seeds ha−1. Partial budget analyses indicated that at present prices the 4% yield advantage offset purchasing and owning costs of a new drill and added seed costs, if planting 250 and 500 ha of soybean.

High Planting Rates Improve Weed Suppression, Yield, and Profitability in Organically-Managed, No-till–Planted Soybean

“…Although creating a within-row gap in the mulch would reduce the weed suppression provided by the rolled cover crops, faster emergence and higher soybean populations (Mirsky et al 2012) could potentially compensate by enhancing soybean competitiveness (Place et al 2009; Wells et al 2015). Our no-till planter setup did not include row cleaners, but the soybean populations in our experiment were similar to those reported under conventional no-till management from previous research in New York (Cox and Cherney 2011; Orlowski et al 2012), as well as other studies in the United States (De Bruin and Pedersen 2008a; Ethredge et al 1989; Lee et al 2008; Walker et al 2010). Still, further modifications to no-till planters will be helpful for improving seed placement and potentially lowering recommended planting rates, if the performance of such configurations is consistently demonstrated.…”

“…Estimated changes in partial return were also calculated for a range of soybean seed costs ($0.00029 to $0.00051 per seed) and market prices ($0.74 to $1.14 kg −1 ). The estimated change in partial return reflects the economic loss or gain from planting soybean at 687,000 seeds ha −1 (the average of the predicted economically optimal planting rates from both sites), rather than at the recommended rate of 321,000 seeds ha −1 for conventional soybean planted at 76-cm row spacing (Cox and Cherney 2011; Orlowski et al 2012). The predicted yield advantage of 349 kg ha −1 when planting at 687,000 seeds ha −1 instead of 321,000 seeds ha −1 was used for Y s , and the additional number of seeds (366,000 seeds ha −1 ) required at the higher planting rate was used for R s in Equation 4.…”

“…In this research, we compared a wide range of planting rates in organic no-till–planted soybean. Planting rates of more than double the recommended rate of 321,000 seeds ha −1 in 76-cm-wide rows for conventional production in New York (Cox and Cherney 2011; Orlowski et al 2012) were used to overcome potential seed placement challenges that can be common in rolled cover crop systems, and to ensure an asymptotic relationship between planting rate and yield. By reaching a yield plateau (or decline due to lodging or severe intraspecific competition), we can estimate the economically optimal planting rate.…”

Rolled Mixtures of Barley and Cereal Rye for Weed Suppression in Cover Crop–based Organic No-Till Planted Soybean

“…Soybean was no-till planted in 76-cm-wide rows parallel to the direction of cover crop rolling at a high seeding rate of 740,000 seeds ha −1 . Although this is more than double the recommended seeding rate of 321,000 seeds ha −1 for conventional soybean production at 76 cm row spacing in New York (Cox and Cherney 2011;Orlowski et al 2012), the high rate was used as a cultural weed management tactic. Soybean canopy closure is attained earlier at higher seeding rates, which contributes to weed suppression through increased shading (Arce et al 2009;Bastiaans et al 2008;Place et al 2009;Ryan et al 2011b).…”

Effect of row spacing, seeding rate and nitrogen fertilization on yield and yield components of soybean

“…Reasons given for better yields with narrow rows and higher plant densities are the enhanced early crop growth and the higher leaf area index and light interception (Shibles and Weber, 1966;Envi, 1973;Willcott et al, 1984;Bullock et al, 1998). Further, a decrease of weed infestation and weed biomass production has been shown by both planting in narrower rows (Orlowski et al, 2012) and increasing plant densities (Liebert and Ryan, 2017). The N demand of soybean is partly fulfilled by biological nitrogen fixation (BNF).…”