Productivity of Field Pea (Pisumsativum L.) and Spring Oat (Avena sativa L.) Grown as Sole and Intercrops Under Different Nitrogen Levels

Authors

• Chengchou Han, University of Nebraska-Lincoln
• Christopher Borman, University of Nebraska-Lincoln
• Dori Osantowski, University of Nebraska-Lincoln
• Jeremy Wagnitz, University of Nebraska-Lincoln
• Katja Koehler-Cole, University of Nebraska-Lincoln
• Kevin Korus, University of Nebraska-Lincoln
• Evan Sonderegger, University of Nebraska-Lincoln
• Rodrigo Werle, University of Nebraska-Lincoln
• Tara Wood, University of Nebraska-Lincoln
• John L. Lindquist, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2012

Citation

Journal of Agricultural Science (2012) 4:136–143

doi: 10.5539/jas.v4n11p136

Comments

Open access

CC BY 3.0

Abstract

Intercropping cereal grains and legumes has potential as an alternative cool-season forage crop in low-input farming systems. The objectives of this study were to quantify the effects of density, species proportion, and nitrogen (N) supply on the biomass accumulation of field pea and spring oat grown as sole or intercrops. Greenhouse experiments were conducted using an additive series experimental design. Treatments included three fertilizer N rates and 20 density/proportion combinations in a randomized complete block with four replications. Sole plant densities included 2, 3, 4, 5 plants of each species pot-1 (16 cm in diameter, 16 cm in height). The species ratios per pot for the intercrop included 1:1, 1:2, 1:3, 1:4, 2:2, 2:3, and 3:5 and their reciprocals. Nitrogen treatments included urea at 0, 0.2, or 1.0 g N pot-1 in a split application. Plants were harvested and oven dried to constant weight at 46 days after planting. As density increased, sole cropped oat and field pea biomass increased. In the intercrop, oat showed greater biomass accumulation at higher N levels, whereas field pea biomass was reduced at the highest N level. In both sole and intercrop, oat was more sensitive to intraspecific competition than field pea. Niche differentiation was observed only at the highest N level. At higher N and lower total density, mixtures yielded more than monocultures, indicating that intercropping of field pea and spring oat may be beneficial. Results from this study can aid in future field research to determine optimum density for each species and N rates to be applied in field pea-oat intercropping systems.