ABSTRACT
A field study was conducted in the winter season of 2017 at the
Agricultural Experimental Station of Wadi Suder, south Sinai (D.R.C.),
to evaluate the effect of soil organic matter, trickle irrigation depth and
bio-fertilizer (Azotobacter chroococcum, Bcillus megatherium and
Bacillus circulans) on soil properties such as air permeability, total
porosity, carbon dioxide evolution and microbial activity on quinoa yield
and water use efficiency (WUE) of quinoa yield (Chenopodium
quinoawilld). Water use efficiency (WUE) was calculated as a result of
cumulative improvement of studied parameters. The results revealed that
soil air permeability increased by 49.9% with increasing the organic
matter. Trickle irrigation depth reduced the permeability by 7.2 % when
depth reached 10cm and 44.6% at 20cm depth. For bio-fertilizers, soil
permeability increased by 48, 47 and 52% as general medium increase
for (Azotobacter chroococcum, Bcillus megatherium and Bacillus
circulans respectively, these increases achieved when organic matter
increased by 100% at zero, 10 and 20cm of trickle irrigation depth.
Whilst, Bcillus megatherium as a sole treatment surpassed other bio
fertilizers. Meantime, air permeability increased by 112% as a result of
increasing porosity by 9% this mean that every 1% of porosity
improvement led to increasing respiration 12%. Also, soil respiration
improved by increasing carbon dioxide evolution whatever, increasing
respiration by 112% refer to increasing CO2 evolution by 84% (every 1%
CO2 increase led to increased respiration by 1.33%) Total porosity
decreased by trickle depth by 2.7%, while comparing to control it
increase at each depth, this increase reached 9.6, 8.03 and 6.79% for
depths zero, 10 and 20cm respectively. Biofertilizers also increase soil
porosity by 7.6, 9.2 and 8.08% for A.chroococcum, B.megatherium and
B.circulans comparing to control. Also, total porosity increased by
increasing additive organic manure from 0.5 to 1% by 5.1%. Quinoa seed
and straw yields promoted by 22 and 21% as organic matter increase for
Egypt. J. of Appl. Sci., 35 (5) 2020 75-92
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seed and straw yields respectively. Meantime, irrigation depth and
biofertilizers haven't direct significant effect however, they hve an
important role though indirect effect on soil permeability, total porosity
and soil respiration. Also, permeability increasing by 112% enhanced
seed and straw yields by 82% (725kg/fed.) and 92 %( 884kg/fed.), for
seed and straw yields respectively. This means that every 1%
improvement in permeability led to increase in seed and straw by
6.5kg/fed., and 8kg/fed., respectively. Water use efficiency for seed and
straw affected significantly by organic matter. In contrast, irrigation
depth, and carbon dioxide have a non significant correlation with the two
yield parameters, while air permeability show the values (r= 0.505*, r=
0.435NS), for water use of seed and straw, respectively. Carbon dioxide
and permeability when coupled with organic matter as mixing technique
show significance correlation value with water used of seed and straw.
CO2 increased with different biofertilization treatments, maximum value
obtained with phosphate dissolving bacteria (B.megatherium), depth of
latellier and organic matter 10 T/fed being 13.1 mg CO2/100g dry
soil/24 hr with 85% of increase over control.