Micro-Nutrient Fertilization of Dry Pea: Effects on Grain Yield.

Dry pea (Pisum sativum L.) is an important crop in the dryland cropping systems of the Northern Great Pains of the USA. Micronutrient deficiency in dry pea is suspected in the area due to its shallow root system compared with cereals and oilseed crops together with continuous farming without micronutrient fertilization. We evaluated micronutrients foliar application rates on dry pea yield and mineral content at two locations in North East Montana from 2016 to 2017. In 2016, the results showed that grain yield increase due to micronutrient fertilization at Richland location was substantial. The mean grain yield increase over the control ranged from 538 kg ha^-1 to 1210 kg ha^-1 for 2.2 kg ha^-1 Fe and 1.1 kg ha^-1 Cu application, respectively. The response at Sidney dryland was only significant to boron application with yield increase of 375 kg ha^-1 over the control when 1.1 kg ha^-1 boron was applied. The response in 2017 was low due to very low precipitation during the growing season. The results showed that areas like Richland with high yield potential need micronutrient fertilizer application even if the soil test values showed micronutrient level above critical value.