Konkurrenz und Ertragsvorteile in Gemengen aus Erbsen (Pisum sativum L.) und Hafer (Avena sativa L.)

In field trials on a fertile fluvisol in 1995 and 1996 near Göttingen, Germany, pea (Pisum sativum; cv. Messire/conventional leafed, cv. Profi/semileafless) and oats (Avena sativa; cv. Alf) were grown as sole crops and in substitutive mixtures. The sole crops were established at 80 pea seeds m^?2 and 300 oat seeds m^?2. The mixtures consisted of 67 % (pea) and 33 % (oats) of the monoculture densities, respectively. Interactions of cv. Messire or cv. Profi and oats were similar in 1995 and 1996. The mixtures outyielded the monocultures with respect to total above ground dry matter (RYT = 1.15) and grain yield (RYT = 1.09). Grain yield of pea and oats averaged 4.9 t ha^?1 in monocultures and 5.5 t ha^?1 in mixtures. Oats was relatively the stronger of the two competitors. Decreasing number of pods per plant could be highlighted as the factor for a lower pea seed frequency in the yield of the mixtures. For oats the number of panicles per plant and kernels per panicle were higher in the mixtures compared with the oat monocultures. The average amount of the harvest index (HI) was 0.52 for pea and 0.46 for oats. Favourable growth conditions increased HI values however, prolific vegetative growth in the mixtures resulted in lower HI values. The predicted RYT‐values estimate the maximum combined grain yield of 6.3 t ha^?1 in the mixture of 87 % pea (70 seeds m^?2) and 13 % oats (39 kernels m^?2).