MINERALS CONSTITUENTS, TOTAL FREE AMINO ACIDS AND NITRATE REDUCTASE ACTIVITY OF POTATOES (Solanum tuberosum, L.)AS AFFECTED BY BIO-AND MINERAL FERTILIZERS .

Helaly, M. N.; Ramadan, E. A.

doi:10.21608/jpp.2009.116963

MINERALS CONSTITUENTS, TOTAL FREE AMINO ACIDS AND NITRATE REDUCTASE ACTIVITY OF POTATOES (Solanum tuberosum, L.)AS AFFECTED BY BIO-AND MINERAL FERTILIZERS .

Document Type : Original Article

Authors

Dept. of Agric. Botany, Fac. of Agric., Mansoura Univ., Egypt.

10.21608/jpp.2009.116963

Abstract

During the two growing seasons, nitrogen, phosphorus and potassium concentrations and their content of potato shoots were negatively affected by decreasing NPK dose less than the recommended one (control).However, bio-fertilizers application, overall NPK dose, significantly increased N, P and P concentrations and their contents. The most effective strain was found with NFB when used individually or incombination with the otherstrains used. Therefore, NFB+PDB+SB recorded high values regarding N, P and K concentrations and their content.
The interaction treatments, indicate that, bio-fertilizers counteracted the depressing effects of NPK stress and showed an increase in N, P and K concentrations and their content in potato shoots. On the other hand, No₃^-concentration and nitrate reductase activity (NRA ) were decreased whereas, free amino acids were increased. Inoculation with the three bacterial strains used recorded best results in this respect.

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