Updated December 2, 2016:
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Title – Seeding date, cultivar, and location influence on soybean performance and phenology in eastern North Dakota
Principle Investigator(s): Burton Johnson, Dept. of Plant Sciences, NDSU Dept. 7670, Fargo, ND 58108-6050, phone 701-231-8895, fax 701-231-8474, Burton.Johnson@ndsu.edu
Dates of research proposal: July 1, 2014 to June 30, 2015 and July 1, 2015 to June 30, 2016
Soybean cultivar maturity rating and seeding date were evaluated at Carrington (northern), Prosper (central), and Lisbon (southern), ND, locations to determine yield response for cultivars from three maturity ratings, as seeding date was delayed from mid/late May to early/mid July in the 2014 and 2015 growing seasons. Maturity ratings were 00.9, 0.7, and 1.4, and seeding dates were spaced at about 10-day intervals, for a total of six seeding dates.
This research is important for producers from different locations in selecting seeding dates for optimum yield performance from soybean cultivars with different maturity ratings. Later maturity varieties can offer higher yield potential; however, delayed planting and uncertainty of growing season duration often dictates selection of earlier cultivars to reduce production risk from early fall frosts that may result in low yield of later maturity cultivars, because of not reaching physiological maturity.
In 2014, the Carrington and Prosper locations cultivar maturity rating and seeding date yield responses ranged from 30 to 45 bu/acre and 40 to 64 bu/acre, respectively, between Date 1 and Date 4 for 00.9 and 0.7 maturity rated cultivars, respectively (Table 1). Yield for the late maturity group 1.4 cultivar was 17 and 26 bu/acre at seeding Date 4 at Carrington and Prosper, respectively. This indicates seeding later than June 12 resulted in substantial yield reduction at these locations for the late maturity rating cultivar. At the southern Lisbon location, yield was 36 bu/acre at seeding Date 4 on June 23 and 46 bu/acre at seeding Date 3 on June 12.
In 2015, the Carrington, Prosper, and Lisbon locations cultivar maturity rating and seeding date yield responses ranged from 13 to 23 bu/acre, 28 to 42 bu/acre, and 24 to 39 bu/acre, respectively, between Date 1 and Date 4 (Table 1). Consequently, there are no clear maturity rating seeding date yield responses at Carrington in 2015 due to constricted yields. At the Prosper location in 2015, greater than 30 bu/acre yields were achieved from Dates 1 through 3 for maturity ratings 00.9 and 0.7, and Dates 1 through 4 for maturity rating 1.4. At the Lisbon location the 0.7 maturity rating cultivar did not yield greater than 30 bu/acre at any of the seeding dates. Yield for the 00.9 maturity cultivar was greater than 30 bu/acre for seeding Dates 1 and 2. The 1.4 maturity rated cultivar at seeding Date 1 yielded 39 bu/acre with later seeding Dates 2, 3, and 4 yielding between 30 and 33 bu/acre.
Based on this study with six environments, seeding date recommendations for 00.9 and 0.7 maturity ratings and yield potential of 30 bu/acre or greater are from seeding on/before June 23, and for maturity rated cultivars 1.4 on/before June 11. Also, yield was generally greatest at the earliest and second seeding dates for each maturity rating.
This soybean research will provide producers with important information about late or replanting soybean performance compared to alternative production strategies regarding profit potential. Cropping alternatives to late-seeded soybean could be short-season crops such as buckwheat and millet, warm season forages, and cover crops. Perhaps late-seeded soybean could follow an early maturing winter annual oilseed crop (camelina) that is harvested in late June/early July. The study proposal provides support for a graduate student to develop research skills leading to a career that will contribute to agricultural sustainability.