Two field trials were carried out in 2002 and 2003 seasons on sweet potato
cv. Abeese, at EI-Bramoon Agric. Farm of EI-Mansoura Hort. Res. Station. The
research aimed at studying the effect of foliar nutrition with a mixture of Fe, Mn and
Zn, each at 100 ppm, vascular arbuscular mycorrhiza (VAM) and Phosphorein, as bio-
phosphorus fertilizer, and mineral phosphate fertilizer at 0, 30, 45 and 60 kg P20slfed.,
on chemical composition of leaves and nutritional status of cured roots of sweet
potato. Results indicated that foliar application of micronutrients significamly increased
N contents of leaves and cured roots, P contents of cured roots and K contents of
leaves, in both seasons. Also Fe, ln and Mn contents of both leaves and tuber roots
Significantly increased in response to foliar spray with micronutrients. Using P₂0₅ at 60
kg/fed. as mineral fertilizer, or VAM, as bio-fertilizer resulted in best significant
increases in N, P, K, Fe, Zn, and Mn, in leaves and cured roots, in both seasons.
Organic composition, i.e., total carbohydrates, reducing, non-reducing, total
carotenes and dry matter, of cured sweet potato roots were significantly increased as
a result of treating plants with either micronutrients, or mineral phosphorus fertilizer at
30, 45 or 60 kg P20sl fed., or by VAM or Phosphorein as bio-phosphate fertilizer.
Positive interactions among micronutrients, mineral P-rates and bio-phosphorus
fertilizer, on chemical composition of leaves and cured roots were detected.