ORIGINAL RESEARCH PAPER Grain yield and quality characteristics of different genotypes of winter pea in comparison to spring pea for organic farming in pure and mixed stands Peer Urbatzka & Rüdiger Graß & Thorsten Haase & Christian Schüler & Dieter Trautz & Jürgen Heß Received: 15 February 2010 / Accepted: 15 September 2011 / Published online: 27 September 2011 # Springer Science & Business Media BV 2011 Abstract High grain yields are difficult to achieve for common spring pea (SP), mainly as a result of its relatively low competitiveness and yield instability. In field experiments, seven different genotypes of winter pea (WP) were analysed for their yield performance and yield stability in comparison to one SP in pure and mixed stands (two replacement designs with cereal) at two experimental sites in four and two growing seasons, respectively. Additionally, in a selection of treatments, parameters of grain quality were analysed. Two of the seven genotypes cannot be recommended for cropping in climates where there are frequent incidences of frost in winter, due to their poor winter hardiness. The pea grain yield of the highest-yielding WP grown in mixed stands (overall mean of 2.4 tDM ha -1 ) was higher than in a pure stand, with 1.8 and 1.9 tDM ha -1 for WP and SP, respectively. Moreover, the concentration of valuable substances (crude protein, amino acids) in WP was comparable to SP, but the concentration of unfavour- able secondary compounds (tannin, trypsin inhibitor activity) was significantly higher. WP showed higher yield stability than SP, and negligible weed infestation was observed for WP, but not for SP. Hence, using WP–cereal mixtures provides an alternative to crop- ping SP, but awareness of the potential constraint to its use as feedstuff for monogastrics is required. Keywords Pisum sativum . Grain legumes . Mixture . Weed suppression . Resistance to lodging Introduction Growing spring peas in pure stands is often consid- ered difficult because of their low weed suppression (e.g., Corre-Hellou and Crozat 2005; Saucke and Ackermann 2006), poor resistance to lodging (Schouls and Langelaan 1994; Stelling 1997), high yield instability (Stelling 1999), and pronounced sensitivity to fungal diseases, often resulting in low grain yield. Consequently, cropping of spring peas and other grain legumes has declined greatly in many Org. Agr. (2011) 1:187–202 DOI 10.1007/s13165-011-0015-2 R. Graß : T. Haase : C. Schüler : J. Heß Department of Organic Farming and Cropping Systems, University of Kassel–Witzenhausen, Germany, Nordbahnhofstr. 1a, 37213 Witzenhausen, Germany D. Trautz Faculty of Agricultural Science, University of Applied Science, Oldenburger Landstraße 24, 49090 Osnabrueck, Germany Present Address: P. Urbatzka (*) Bavarian State Research Centre of Agriculture, Institute for Agricultural Ecology, Organic Farming and Soil Protection, Lange Point 12, 85354 Freising, Germany e-mail: peer.urbatzka@lfl.bayern.de