Optimal soybean maturity group selection is influenced by planting date in northern production systems

Abstract Changing climate conditions have resulted in a shift towards longer growing seasons Michigan and other northern U.S. states, providing soybean [ Glycine Max (L.) Merr.] growers an opportunity to achieve early planting dates (PDs). However, increasingly variable spring precipitation may result wide range of PDs. Current maturity group (MG) recommendations are based only on optimal PD not fully utilize the available season. To determine how MG selection should be adjusted PD, six varieties ranging from 1.0 3.5 were planted four PDs (from late April June) during 2018 2019 at two locations Michigan. Seed yield increased by average 286, 171, 73.0 kg ha −1 for each 0.5‐MG increase when was conducted day year (DOY) 120, 140, 160, respectively. When delayed DOY 180, there reduction 51.4 increase. The using correlated with seeds m −2 which mainly driven consistent cumulative degree days pod seed set. Results this study indicate that can profitability adjusting such maximum season is utilized. Specifically, late‐season maximize profits.