Effect of nitrogen phosphorus and molybdenum fertilizer application on reproductive organ development and yield of the overwintering pea cultivar no. 11 and its relation to nitrogen fixation effectiveness
Kostov, K.; Petkov, N.; Popov, N.
Rasteniev'dni Nauki 25(6): 40-45
1988
ISSN/ISBN: 0568-465X Accession: 007254689
A field fertilizer application trial was carried out with the overwintering pea cultivar No. 11 in 1986-1987 in Sadovo for the purpose of assessing the effect of N, P and Mo fertilizer application on the reproductive organs and yield and its relation to nitrogen fixation, determined by nitrogenase activity. It was found that application of phosphorus alone had highest positive effect on reproductive organ development and seed yield of peas, followed by application of single molybdenum application. Combined phosphorus-molybdenum fertilizer application did not increase the yield. Low nitrogen rates stimulated reproductive organ development and had a positive effect on the final amount of yield, while the high rates had negative effect due to the low effectiveness and the short duration of symbiotic nitrogen fixation. No accumulating effect was observed by nitrogen + phosphorus fertilizer application, a fact proving that in the presence of added phosphorus the peak cultivar studied does not prequire industrial nitrogen.