Prices of mineral fertilizers are getting higher nowadays, so that this
experiment was designed. In a private farm in the New Vally governorate,
different fertilizer combinations; organic, bio and mineral sources were used
in this study using potato (Cara cv.) in sandy soil in the two successive
winter seasons of 2019/2020 and 2020/2021. Results showed that
inoculating potato plants with Biofert (as a N-fixing bacteria) in the
presence of ―half of the recommended doses of organic manures‖ (as
Farmyard Manure, FYM + Poultry Manure, PM) gave the highest mean
values of all studied growth (emergnce %, plant height, number of branches,
fresh and dry weight of potato plant foliage) and yield characters (number of
tuber/plant, total yield ton/fed, average weight of tuber g/plant and average
weight of marketable tubers >45g (ton/fed)). The highest mean values of
those characters were obtained from potato plants treated with the
combination of FYM + PM + Biofert + 100% of NPK dose comparing with
the control treatment. From the obtained results, it could be recommended
that inoculating potato plants with the Biofert (as N-fixing bacteria) and
Biopotass (as K-solubilizing bacteria) combined with compost (FYM) +
(PM) and 75% of the recommended doses of mineral fertilization (NPK) is
the best for potato production to get the highest economic yield of potato
with the best qualities of marketable tubers.