EFFECT OF PHOSPHORUS FERTILIZATION AND SEEDS INOCULATION WITH PHOSPHATE DISSOLVING BACTERIA ON MICROBIOLOGY OF RHIZOSPHERE, FABA BEAN YIELD AND YIELD COMPONENTS

Document Type : Original Article

Authors

1 Microblology and Soil Sci. Depts., Fac. of Agric., Mansoura University, Mansoura, Egypt.

2 Soil, Water and Environ. Res. Inst., ARC, Cairo, Egypt.

Abstract

Two field experiments were carried out al Sakhs Agricultural Research Stalion
using inoculated faba bean seeds variety Improved Giza 3 during the two successive
seasons of 1998/1999 and 199912000. The inoculation was done using phosphate
dissolving bacterial strain namely Bacillus mega/herium var.phosphaticum. Different
levels of superphosphate (P20S kg/fed) were also used with the bacterial inoculation
to examine their effect on microbiology of raba bean rhlzosphere, yield and yield
components and NPK upt"ka as well.             .
Obtained data showed significant differences (P< 0.01) between inoculated
treatments and uninccufDted ones regarding the five bacterial 9roups examined under
all level of superphosphate applied. These bacteria are P·dissolvers, total viable
bacteria. Rhizobium spp < /em>., Azotobacter spp < /em>. and Arosp < /em>iril/um spp < /em>.
Concerning the growth characters of taba bean, the data of plant height and
number of branches showed significant increase with bacterial inoculation and
superphosphate levels used during the two successive cultivation seasons.
The highest values of pod seeds, 100-seed weight, seed yield and straw yield
were achieved under bacterial inoculated treatment at all levels or superphosphate
used. After harves:ing. the three main elements, nitrogen, phosphorus. and potassium
recorded Significant increase towards the bacterial inoculation together with
superphosphate either for seed. shoot, or for straw. Obtained data proved also Ihe
importance or biofertilizer represent in P-dissolving bacteria as well as using
superphcsphate fertilization less than the recommended level. This can also lake part
in reducing the pollution of the soil from the chemical showed be added every year.
Furthermore. this also increased the yietd of taba bean and increase the nutritive
values as well.