Soil Properties Related to the Occurrence of Rock Phosphate-Solubilizing Bacteria in the Rhizosphere Soil of Faba Bean (Vicia faba L.) in Morocco

Abstract

This study focused on revealing the correlations between rock phosphate-solubilizing bacteria (PSB) counts and differing properties of the rhizosphere soil. One hundred and thirty-two samples of rhizosphere soil of faba bean (Vicia faba L.) were collected and analyzed from 14 agricultural areas in Meknes, Morocco. The results revealed that all the samples were inhabited with indigenous PSB ranging from 3.55 to 0.002 (×10 5 CFU/g soil). The correlations between PSB counts and cation exchange capacity, available phosphorus (P), and pH were insignificant; on the contrary, a highly significant correlation (p ≤ 0.01) was found between the numbers of PSB and total soil bacteria (TB) (r = 0.80), total nitrogen (N) (r = 0.86), and organic matter (r = 0.90). This research enhances our knowledge on PSB population and their interaction with physical, chemical, and biological properties of the rhizosphere soil of faba bean to provide a new index for better use in organic agricultural practices.

Diversity and Phosphate Solubilization Efficiency of Phosphate Solubilizing Bacteria Isolated from Semi-Arid Agroecosystems of Eastern Kenya

“…Soil pH have also been shown to have an impact on the abundance of PSB. 40 This finding is in agreement with the finding of Ndung'u-Magiroi et al, 24 who showed that the population of PSB is higher in soils with low phosphorus levels. One mechanism in which PSB work is believed to be through production of organic acid which lowers the pH.…”

“…These values was within the ranges of a similar study conducted in Morocco which reported values of between 0.0021 and 7.24 × 10 5 CFU g - 1 soil. 40 However, the percentage of culturable PSB to total culturable bacteria was lower than the finding of the same study. In their study, Nannipieri et al, 41 showed that soil properties and land use affect the population of soil bacteria.…”

Identification, characterization and optimization of phosphate solubilizing rhizobacteria (PSRB) from rice rhizosphere

“…The greater number of catalase positive PSRB is strongly supported by the findings of Bumunang and Babalola, 2014 , Shrivastava, 2013 , Shruti et al, 2013 who also reported similar findings for Oryza sativa from other countries. PSRB are known to be found in wide variety of soil types but their function is heavily impacted by different environmental variables that include organic matter, cation exchange capacity, temperature, salinity, pH and soil composition, ( Mujahid et al, 2014 , Zaidi et al, 2014 , Rfaki et al, 2018 ). Thus, tolerance to intrinsic and extrinsic stress is highly significant for microorganism growth, survival and establishment in the rhizospheric soils which was tested in the current research at ex situ (laboratory) conditions by optimizing the developmental processes of the selected strains at different pH, temperature and salt concentrations.…”

Isolation and characterization of phosphate solubilizing bacteria naturally colonizing legumes rhizosphere in Morocco

“…On the other hand, as discussed by Khan et al (2010) , although there is a clear potential for the development of inoculants with PSBs, their widespread application remains limited by a poor understanding of microbial ecology, dynamics population in soil, and inconsistent performance in a range of environmental factors. However, although PSBs are present in the majority of soils, their performance is strongly influenced by environmental factors such as soil type, temperature, salinity, cation exchange capacity, pH, organic matter, and availability of substances in soils ( Rfaki et al, 2018 ; Masdariah et al, 2019 ). Similarly, Namli et al (2017) stated that resistance to extreme environmental conditions is an important characteristic that allows inoculant bacteria to survive and maintain optimal population numbers throughout a specific crop life cycle.…”