ABSTRACT
The use of organic and synthetic soil amendments such as compost,
farmyard manure and polyacrylamide can be considered as a specific
management to improve the soil physical and chemicals properties of
sandy soil along with decreased irrigation water consumptive use and
water use efficiency. So, a field experiment was carried out at the Farm
of El-Ismailia Agricultural Research Station, El-Ismailia Governorate
Egypt in winter season 2014/2015 cultivated with wheat (Triticum
aestivum L., cv Giza 168 ) under three water deficit at (100%, 75% and
50% of crop evapotranspiration, ETc) and soil amendments (none,
compost, farm yard manure and polyacrylamide). Also, the effect of
allowable soil moisture depletion (ASMD) at 25%, 50% and 75% of total
soil available water was studied on peanut crop (Arachis hypogaea L.
Giza 6) under the same previous soil amendments. Wheat and peanut
water consumptive use, water use efficiency and both yields components
along with physical and chemicals properties of studied sandy soil were
also evaluated.
Results indicated that, the highest actual irrigation treatment was
recorded at rate of 100% (ETc) treatment, for wheat crop, while the
highest one was recorded under 25% (ASMD) for peanut crop as
compared to other irrigation treatment. Also, the obtained results show a
noticeable reduction in soil pH and salinity as a result of treating the soil
with different soil amendments compared to control. The effect was more
obvious in case of applying FYM and irrigation treatments 100% ETc for
wheat and 25% ASMD for peanut crops as compared to other treatments
and control. Also, OM and CEC values were increased in case of used
FYM soil amendment as compared with other treatments and control for
both studied crops under different irrigation treatments. However, the
highest diameters of dry aggregates were positive affected by FYM and
irrigation treatments 100% ETc for wheat and 25% ASMD for peanut
crops as compared with other treatments and/or control. In addition, the
values of soil bulk density of soil profiles treated by all treatments were
relatively low compared to those of control, whereas the maximum
Egypt. J. of Appl. Sci., 36 (3) 2021 36-61
decrease exists in soil treated by FYM and irrigation treatments 100%
ETc for wheat and 25% ASMD for peanut crops as compared with other
treatments and control. The same trend was true in case of the soil total
porosity values. It is clear that application of all treatments decreased soil
hydraulic conductivity (cm h-1) values when compared to the control.
Moreover, the best treatment in decreasing soil hydraulic conductivity
(cm h-1) value of FYM and irrigation treatments 100% ETc for wheat
and 25% ASMD for peanut crops as compared with other treatments and
control. Whereas the highest values of field capacity and available water
existed in case of the same treatments.
Finally, applying FYM and irrigation treatments 100% ETc for
wheat and 25% ASMD for peanut crops as compared with other
treatments and control increased significantly the yield and yield
components of both wheat and peanut. The beneficial effects of the
applied treatments on wheat and peanut yields could be arranged in the
following order: FYM>compost > polyacrylamide>control under
different irrigation treatments.