Effect of Planting Date and Starter Fertilizer on Soybean Grain Yield

Abstract

In the Midwest, soybean [Glycine max (L.) Merrill] is planted over a large window of time. Starter fertilizer may be beneficial at earlier planting dates when cool soils limit nutrient availability or at later planting dates when the growing season is shortened. The objective was to evaluate the effect of planting date and starter fertilizer on soybean nodulation, biomass, canopy closure, grain yield, and grain quality in high‐yielding environments. A trial was conducted at the Western Agricultural Research Station (WARS) in 2013 and 2014 and the Northwest Agricultural Research Station (NWARS) in 2014. Treatments included three to four planting dates ranging from May through early July and five starter fertilizers (none, urea, triple superphosphate, urea + triple superphosphate, and diammonium phosphate) applied 2 inches below and 2 inches beside the seed at planting. Starter fertilizer had a very small effect on soybean nodulation, biomass, canopy closure, and grain quality. In 2013 and 2014 at the WARS location, yield decreased an average of 0.58 bu/acre per day from the first to last planting date. Fertilizer did not increase soybean yield at any of the site‐years. All sites had soil phosphorus (P) levels greater than the critical level of 15 ppm. At soil P levels >15 ppm, a yield response to fertilizer is unlikely. Nitrogen fixation and mineralization were adequate to meet the crop demand. Planting in early May without starter fertilizer provides the greatest chance to consistently maximize soybean yield and profitability when N and P are not limiting.

Soybean yield and crop stage response to planting date and cultivar maturity in Iowa, USA

“…Our data combined with nine other studies ( Figure 8) showed that soybean yield response to delayed PD has not changed for Iowa and much of the major soybean growing region of the United States despite changing climate patterns (Anderson & Vasilas, 1985;Beaver & Johnson, 1981;De Bruin & Pedersen, 2007a;De Bruin & Pedersen, 2007b;Elmore, 1990;Hankinson et al, 2015;Oplinger & Philbrook, 1992;Pedersen & Lauer, 2003;Wilcox & Frankenberger, 1987). The locations in this review contain similar variety maturities and growing season length to our Iowa locations.…”

“…Current recommendations in Iowa advise an optimum planting date during the last week of April for southern Iowa and the first week of May for northern Iowa (De Bruin & Pedersen, ). In the Midwest, Egli and Cornelius () found that planting could be delayed to 30 May before a resulting grain yield loss of 0.7% d −1 occurs and Hankinson, Lindsey, and Culman () found that yield decreased by 0.04 Mg ha −1 d −1 from the first to last planting date (5 May to 2 July mean first and last day of planting, respectively). Selecting a favorable cultivar maturity has been studied as a way to mitigate the effect of planting date on grain yield, but has been found to have little to no effect (Anderson & Vasilas, ; Barreiro & Godsey, ; Johnson & Major, ; Raymer & Bernard, ; Wilcox & Frankenberger, ).…”

Variation in nitrogen uptake efficiency in upland rice landraces as influenced by P fertilization

“…The results of this study is concurrent with the findings of other researcher who have reported that P fertilizers do not contribute to increase yield in plant at soil P levels >15 mg/kg (Hankinson et al, 2015). Another study done by Shehu et al, (2010) found that application of P significantly increased dry matter yields plant -1 but no significant increase in N uptake during P fertilization.…”

Soybean seeding rate and fertilizer effects on growth, partitioning, and yield

“…Subsurface banded fertilizer applications have previously been observed to increase early‐season DM and nutrient accumulation in corn ( Zea mays L.) (Niehues, Lamond, Godsey, & Olsen, 2004; Rutan & Steinke, 2018). As soybean growers respond to a changing climate and plant earlier in the season due to warmer air and soil temperatures, similar benefits may exist in soybean production (Hankinson et al., 2015).…”

“…In 2012, 44, 43, and 69% of Michigan soybean hectares were fertilized with N, P, and K, respectively (USDA‐NASS, 2012). Potential for a grain yield increase to fertilizer applications may be dependent on site‐specific factors (i.e., soil and physical properties and precipitation) (Clover & Mallarino, 2013; Hankinson, Lindsey, & Culman, 2015; Warncke et al., 2009). However, grower interest in N, P, K, S, and Zn applications continues to increase due to volatile spring environmental conditions, variable soil texture, decreased atmospheric S deposition in the north‐central United States, perceived increases in micronutrient deficiencies, and to ensure yield potential of modern higher‐yielding cultivars (i.e., yield potential >4500 kg ha −1 ) (Chien et al., 2016; Havlin et al., 2014; Hitsuda, Toriyama, Subbarao, & Ito, 2008; Osborne & Riedell, 2006; Sutradhar, Kaiser, & Behnken, 2017; Tamagno, Sadras, Haegele, Armstrong, & Ciampitti, 2018).…”