Effect of intercropping normal-leafed or semi-leafless winter peas and triticale after shallow and deep ploughing on agronomic performance, grain quality and succeeding winter wheat yield

Winter peas (Pisum sativum L.) are a promising alternative to spring peas in organic farming. Intercropping winter peas and cereals may be a beneficial way to improve lodging resistance in normal-leafed and weed suppression in semi-leafless winter peas. At the same time, there is an increasing interest in a reduction in tillage intensity, e.g. shallow ploughing. A normal-leafed, coloured-flowered (cv. E.F.B. 33) and a semi-leafless, white-flowered winter pea (cv. James) were cultivated as sole crops or in intercrops with triticale (Triticosecale Wittmarck) on a loam soil under Northern German conditions during two seasons (2009/2010, 2010/2011) and compared for winter survival, lodging resistance, yield performance, grain quality and succeeding winter wheat yield. The two ploughing depths were short-term shallow ploughing to 10-12 cm and continuous deep ploughing to 25-27 cm. Intercropping did not improve winter survival, which depended on pre-winter development. Owing to the low lodging resistance of normal-leafed winter pea E.F.B. 33, sole cropping is not advisable. Intercropping normal-leafed winter pea E.F.B. 33 and triticale resulted in a better yield performance (2.54-3.39 t d.m. ha−1) than the semi-leafless winter pea James sole (0.97-1.79 t d.m. ha−1) or intercrops (2.05-2.86 t d.m. ha−1). E.F.B. 33 had significantly higher grain crude protein, crude fibre and macronutrient contents, whereas the crude fat, starch and sugar content as well as the energetic feed value were higher in James. Wheat yields after E.F.B. 33 sole and intercrops were higher than after the corresponding James sole or intercrops. The biomass production, yield performance and the energetic feed value of winter pea sole and intercrops were comparable between ploughing depths or higher after shallow ploughing. Thus, E.F.B. 33-triticale intercrops provided better results than James sole or intercrops, except for the energetic feed value, and shallow ploughing was a good alternative to deep ploughing for the cultivation of winter peas.