Activity of symbiotic nitrogen fixation and productivity of common vetch depending on soil pH and the amount of phosphorus, potassium, boron and molybdenum
Khramoi, V.K.; Posypanov, G.S.; Rakhimova, O.V.
Izvestiya Timiryazevskoi Sel' skokhozyaistvennoi Akademii 2: 56-71
In pot trials in 1989-90 and 1993, Vicia sativa was grown in dernopodzolic sandy soil adjusted to pH 4.3-7.1 with optimum nutrient concentrations and with different levels of P, K, B and Mo at pH 6.5. Nodule weight and nitrogenase activity were highest at pH 6.0-7.1 and assimilation of atmospheric N was 52% higher than at pH 5.1. Seed yield was highest at pH 6.6. Symbiotic activity and seed yield were higher with 165 than with 45 or 75 mg P2O5/kg soil.