Effect of Organic Nitrogen Amendments and Irrigation Regimes on Agronomic Performance of Two Quinoa (Chenopodium quinoa Willd.) Cultivars.

Quinoa (Chenopodium quinoa Willd.) is a native crop of South America. It is high in protein and considered a “superfood” because it contains all of the essential amino acids to meet the human dietary requirement. In 2014, a study was conducted at the Irrigated Agriculture Research and Extension Centre (IAREC) in Prosser, Washington to evaluate the performance of two different Quinoa cultivars in response to different nitrogen (N) and irrigation rates. The experiment was laid out in RCBD in a strip-plot arrangement with different irrigation regimes as main treatment and different rates of N, applied using certified organic compost, as sub-treatment, replicated three times. For the three irrigation regimes, soils were held at 40%, 80% and 100% of field capacity. Certified vegetation based compost was applied to supply 0 kg/ha, 25 kg/ha, 50 kg/ha, 75 kg/ha and 100 kg/ha N. Two cultivars of Quinoa, Oro de Valle and Cherry Vanilla, were planted in a row planting arrangement. Both the compost and irrigation treatments were significantly related (P ≤ 0.05) to germination, final plant height and the end of season biomass in both cultivars whereas there was not a significant interaction of compost and irrigation treatment on either cultivar. Due to extreme temperatures during the flowering/seed set period in the 2014 growing season there was no seed yield.

The data suggests that the germination rate of Cherry Vanilla was higher than Oro de Valle at 80% and 100% irrigation regime. N rates of 75 kg/ha and 100 kg/ha at 80% and 100% irrigation levels had the greatest plant height and biomass in both cultivars. However, air temperatures exceeding 35 ⁰C during flowering and seed setting prevented seed yield in both Quinoa cultivars.