Seed Yield and Quality of Transgenic High Oleic and Conventional Soybean as Influenced by Foliar Manganese Application
Douglas Alt, Sin Joe Ng, John Grusenmeyer, and Laura E. Lindsey
Soybean growers are interested in specialty crop soybeans with modified oil profiles providing price premiums to help offset low soybean grain prices. High oleic soybeans have been modified to produce high levels of oleic fatty acid, improving frying quality and shelf stability while reducing trans fat (Warner and Gupta, 2005).
Plenish® high oleic soybeans (DuPont® Pioneer®, Johnston, IA) are specialty soybean cultivars that have been genetically modified to limit the amount of linolenic acid and increase the amount of oleic acid in the soybean grain (DuPont® Pioneer®, 2017; Syed, 2015). The effect of manganese (Mn) foliar fertilizer on the oil profile of Plenish® soybean has not previously been examined. The objective of this study was to evaluate the effect of foliar Mn fertilizer on seed yield, protein and oil concentration, and oil profile of transgenic high oleic soybean (Plenish®) and soybean with a normal oil profile (referred here as “conventional”).
- In 2014, the Mn-SO4 application increased soybean grain yield by 2.1 bu/acre at the Wood County location where soybean plants were deficient in Mn. At the other three site-years, soybean grain yield was not affected by Mn application.
- Manganese application did not influence the oil protein content of the soybean grain or alter the oil profile.
- The high oleic cultivars and cultivars with normal oil profile yielded the same at the Wood County location both years.
- In 2014 and 2015 at the Clark County location, the high oleic cultivars yielded 6.1 and 4.0 bu/acre less than cultivars with a normal oil profile, respectively.
- Growers considering planting Plenish® soybean cultivars do not need to alter their Mn foliar fertilizer management.
Methods. The trial was established in 2014 and 2015 at the Ohio State University Northwest Agricultural Research Station in Wood County and the Western Agricultural Research Station in Clark County.
Treatments included cultivar and manganese foliar fertilizer:
Soybean cultivar (Note: Cultivar names ending in “PR” were Plenish®.):
- 2014- Pioneer P29T68PR, P31T11R, P33T34PR, P33T72R, P34T90PR, and P35T33PR
- 2015- Pioneer P29T40PR, P31T11R, P31T96PR, P32T49PR, P33T34PR, P33T72R, P34T90PR, and P35T66PR
Manganese foliar fertilizer (applied at label rate):
- Mn-EDTA (Feast® Micro Master Chelated Manganese, Conklin Company, Inc.)
- Mn-SO4 (Max-In Ultra Manganese Winfield United)
- None (control)
Effect of Mn application on soybean grain yield. Soybean grain yield was influenced by Mn application at the Wood County location in 2014, but not at the other three site-years. The Mn-SO4 treatment increased grain yield by 2.1 bu/acre compared to the control treatment. At the Wood County location in 2014, Mn leaf concentration prior to Mn application averaged 23 ppm and visual deficiency symptoms of interveinal chlorosis were noted. Manganese is likely sufficient when the concentration of Mn in the uppermost fully developed leaf prior to initial flowering is at least 20 ppm (Vitosh et al., 1995). The increase in soybean grain yield with Mn-SO4 application may be attributed to Mn deficiency due to low Mn in the soybean leaves and accompanying visual deficiency symptoms. Below average rainfall at the Wood County 2014 location from May through August and soil pH of 7.7 may have reduced Mn availability causing Mn deficiency in the soybean plants. Although Mn-SO4 also supplies sulfur (S), the concentration of S in the leaf tissue prior to Mn treatment averaged 2.8% which was within the sufficiency range of 2.1-4.0% and was not likely limiting (Vitosh et al., 1995).
Manganese application did not influence grain yield at the Wood County location in 2015 and the Clark County location in 2014 and 2015. Leaf Mn concentration prior to Mn application averaged 44.3, 44.6, and 64.2 ppm at the Wood County location in 2015, Clark County location in 2014, and Clark County location in 2015, respectively. Grain yield increases were not associated with Mn application at these locations because leaf Mn concentration was within the established sufficiency range of 21-100 ppm and not likely deficient (Vitosh et al., 1995).
Grain yield comparison of high oleic soybean to soybean with normal oil profile. When comparing high oleic cultivars to cultivars with normal oil profile, there was no difference in grain yield at the Wood County location in 2014 and 2015. At the Clark County location, high oleic soybean cultivars yielded 6.1 and 4.0 bu/acre less than the soybeans with the normal oil profile in 2014 and 2015, respectively.
Recommendations. The oil profile from the high oleic soybean cultivars was unaffected by foliar Mn fertilizer application despite the Mn deficiency detected at one site-year. High oleic soybean cultivars do not require different Mn management compared to normal soybean cultivars. The normal oleic cultivars showed a slight yield advantage over the high oleic cultivars at the Clark County location.
DuPont® Pioneer®. Plenish® High oleic soybeans. 2017. https://www.pioneer.com/home/site/us/products/soybean/enhanced-oil-soybeans (verified 6 June 2017).
Syed, A. 2015. Specialty/GM vegetable oils: properties and application in food (rapeseed, sunflower, soybean). In: Specialty oils and fats and nutrition: properties, processing, and applications. Ed. Geoff Talbot. Woodhead Publishing, Waltham, MA. p. 184-185.
Vitosh, M.L., J.W. Johnson, and D.B. Mengel. 1995. Tri-state fertilizer recommendations for corn, soybeans, wheat, and alfalfa. Bull. E-2567. Ohio State Univ. Ext. Serv., Columbus.
Warner, K., and M. Gupta. 2005. Potato chip quality and frying oil stability of high oleic acid soybean oil. J. Food Sci. 70:s395-s400.
- Research funded by DuPont Pioneer and the Ohio Soybean Council Moser Award.
- Thanks to OARDC staff for field assistance.
- Salary and research support provided in part by state and federal funds appropriated to the Ohio Agricultural Research and Development Center (OARDC) and The Ohio State University.