Date of this Version
Agronomy Journal 110:4 (2018), pp 1412-1419.
Increased market demand and larger adoption of field pea (Pisum sativum L.) in semiarid west-central Nebraska has provided opportunities to replace summer fallow and diversify crop rotations. As a relatively new crop, its response to different seeding practices has not been evaluated in this eco-region. Field pea grain yield response to seeding depth (25, 50, and 75 mm), inoculation with Rhizobium leguminosarum bv. viciae (yes and no rhizobia inoculant), and seeding rates (35, 50, 65, 75, 90, 105, and 120 plants m–2) was investigated in 2015 and 2016 at five sites in Perkins County, NE. There were no differences in yield for field pea planted at depths of 25, 50, and 75 mm. Yield differences between inoculated and noninoculated field pea were not observed; however, a lack of nodules on noninoculated field pea plants suggests that carryover of rhizobia in soil with a history of field grown 2 to 3 yr previously was not sufficient to initiate nodulation. Seeding rates resulting in plant populations of 45 to 60 plants m–2 provided the highest economic return; an economic penalty (~$1.05 ha–1) may occur for each additional plant per square meter attained over this plant population. Increasing the seeding rate, however, may help farmers manage risks of hail injury, enhance weed suppression, and increase harvest efficiency. Therefore, field pea grown in semiarid west-central Nebraska should be properly inoculated with rhizobia at every planting, seeded in good moisture at depths ranging from 25 to 75 mm, and have final plant population of at least 60 plants m–2.