http://orgprints.org/7596/ Effects of plant based organic fertilizer (faba bean meal) compared to farmyard manure on yield and quality of potatoes and soil organic matter levels Raupp, Dr Joachim Oltmanns, Meike Root crops Composting and manuring Whereas the positive effects of farmyard manure on soil biological properties have been shown in several long-term experiments, no comparable information was available for plant based organic fertilizers. Since 1996 such materials were applied with the same amount of total nitrogen as farmyard manure (100 (kg ha-1) on a poor sandy soil. In 2005 it was found that faba bean meal application caused the same potato yield, and tubers with the same phosphorus content, but lower potassium and slightly increased starch contents compared to farmyard manure. Tuber quality was similar as regards nitrate content. However, as regards crude extract darkening better values have been achieved by farmyard manure. Soil organic matter content was lower with faba bean meal than with farmyard manure. 2006 Conference paper, poster, etc. NonPeerReviewed rtf http://orgprints.org/7596/1/E-ode.doc Raupp, Dr Joachim and Oltmanns, Meike (2006) Effects of plant based organic fertilizer (faba bean meal) compared to farmyard manure on yield and quality of potatoes and soil organic matter levels. Joint Organic Congress, Odense, Denmark, May 30-31, 2006. http://orgprints.org/7596/http://orgprints.org/7596/1/