In two seasons (1986/87 and 87/88), phosphorus ferti—
lizer was applied as ordinary calcium superphosphate (OCSP)
mixed with seeds of field beans (Vicia faba L. cv. Giza
2) at rates of 7.0, 10.5 and 14 kg P/fad. (16, 24 and 32
kg P205/fad.). It caused more growth and gave 57 and 14%
mroe yield at the low and high rates than broadcast, and
37 and 19% more yield at the same respective rates than
banding.
Mixing OCSP with seeds has the same advantage as its
banding in keeping the contact of fertilizer with soil
to minimum P fixation. It also has the further advantage
of securing sample P in the vicinity of seeds, and seedling
roots at the earliest possible stage in crop life, both
of which are crucial for growth and yield. Uptake of N,
P and K as well as seed yield were all increased by this
method.
Under Egyptian conditions of (a)—soils being mostly
clayey or calcareous or both and (b)-OCSP being powdered,
appreciable fixation of P is invevitable; hence, this method
is imperative especially if conditions dictate low rates.
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