Reaction of garden pea (Pisum sativum L.) to inoculation and nitrogen fertilization in Eastern Croatia

Sa？etak Biological nitrogen fixation represents the subject of numerous investigations of the scientific community. The advantages of this process, as already well known while scientific research trials attempts to clarify the interactions of symbionts in this type of nitrogen fixation as well as the influence of abiotic factors on its efficacy. A field experiment was conducted to investigate the influence of garden pea cultivars ('Alicia' and 'Miracle of America'), seed inoculation with nodule bacteria (Rhizobium pisi DSM 30132, and Rhizobium leguminosarum bv. viciae OS–103), and nitrogen fertilization (0, 30 and 60 kg N*ha-1). The observed parameters are: stand density, number of pods, mass of 1,000 grains, mass of pods and grains and grain yield. It was established that all the investigated factors significantly influenced the traits. The seeds inoculated with the indigenous strain R. leguminosarum bv. viciae OS–103 had significantly increased numbers of pods per unit area, grain yield, and the weight of 1,000 grains, while a higher amount of applied nitrogen resulted only in an increase of grain yield. Cultivar 'Alicia' achieved a significantly higher grain yield compared to the 'Miracle of America' cultivars, while application of 60 kg N*ha-1 achieved statistically higher grain yield compared to control. Inoculation with R. leguminosarum bv. viciae OS-103 produced a significantly higher grain yield compared to inoculation with the reference strain R. pisi DSM 30132. The observed parameters were significantly influenced by the garden pea cultivar, seed inoculation with nodule bacteria, and nitrogen fertilization therefore further investigation are needed with new inoculant strains and new cultivars under different agroecological conditions