A field experiment was carried out on a newly reclaimed sandy soil at
South-Tahrir Sector, Al-Behira Governorate, Egypt during the two
successive summer seasons of 2008 and 2009, under sprinkler irrigation
system. This study was conducted to identify the effect of bio-inoculation by
Rhizobium leguminosarum in combination with applied gypsum at the rates
of 0, 0.5 and 1.0 ton fed-1 and iron foliar spray at the rates of 0, 0.3 and 0.6 g
L-1 on improving some soil properties as well as peanut pod or seed yield and
its contents of oil, protein and nutrients.
The obtained data showed that application of gypsum led to improve
some soil properties, i.e., soil bulk density, total porosity, pH and ECe, where
an increased was occurred in soil total porosity. On the contrary, soil bulk
density and pH were decreased, and such favorable effects were achieved at
the highest rate of gypsum. The data revealed also that the available contents
of NPK as macro and Fe, Zn, Mn and Cu as micronutrients in soil after
peanut harvesting increased as a result of bio-inoculation with rhizobium and
gypsum addition, however, the combined treatment of (gypsum at a rate of 1
ton fed-1 with bio-inoculation) gave the best results.
In addition, the applied triple treatment of (bio-inoculation + gypsum +
iron foliar spray) significantly increased the number and dry weight of
nodules plant-1 as well as dry weight of shoot and root of peanut plants at 75
days from sowing. A pronounced increase was achieved in each peanut pod
or seed yield and its contents of oil, protein and nutrients (i.e., N, P, K, Fe,
Zn, Mn and Cu). The greatest values for the abovementioned traits were
recorded with bio-inoculation. Application of gypsum resulted in a
significantly increase for each of the previous peanut parameters, except of
potassium content in seed that tended to decrease with increasing the applied
rates of gypsum.
Iron foliar spray resulted in a significantly increase for each of the
previous peanut parameters in both studied seasons as compared to the
control. The greatest values were attained by iron foliar spray at the applied
rate of 0.6 g L-1, except for P, Zn and Cu contents and uptake that were
significantly decreased with increasing the applied rates of Fe as foliar spray.
Therefore, under the condition of the studied newly reclaimed sandy soil, the
applied gypsum with bio-inoculation plays an effective role for improving
soil characters, increasing the available nutrient contents and raising the
efficiency of iron foliar spray. This of course positively reflected on peanut
yield and improved its seed quality.