“Isolation and Characterization of Phosphate Solubilizing Microorganisms from Soils And Evaluation Their Phosphate Nutrition Of Field Pea (Pisum Sativum L.) In Tokke Kutaye District”

Abstract

Field pea (Pisum sativum L.) is a major pulse crop in Ethiopia. As compared with other cereal crops pulses contains the superior essential amino acids which are a valuable and reasonably priced protein sources. The study aimed to isolate and characterize phosphate solubilizing microorganisms from various soils and assess their phosphate nutrition of field pea (Pisum sativum L.Var) in Tokke Kutaye district. The study was conducted at Ambo University's Agriculture and Veterinary Science and Plant Science College, Guder Mamo Mazemir Campus, from July-November 2024 in both laboratory and greenhouse conditions. The study was experimental design. Total six soil samples of 3kg with two replicates of soil samples taken ranging from 0-20cm was collected and packed in polyethylene bags from Birbirsa, Ajo,Dhaga file and Guder mamo mezemir campus. The experimental pots was laid out in two factorial Randomized Block design combination.The isolation were made in laboratory condition on media of Pikoviskayas agar(PVK) and all isolates were characterized . Out of eight PSB, four active phosphate solubility isolates were selected with PSB1,PSB2,PSB3 and PSB4. Accordingly, findings showed PSB1 have the superior efficiency of phosphate solubilizing ability at 1.71±0.16PSI (cm). According to study findings out of 13 PSF isolates only four fungal isolates selected based on their phosphate solubility efficiency namely PSF1,PSF2,PSF3 and PSF4.Thus,PSF3 showed the highest efficiency in phosphate solubility index(SI) of 1.67cm.The determination P solubilization were evaluated on Aspergillus niger (PSF3),Trichoderma herzanium(PSF2),Aspergilus flavus(PSF1) and Penicillium oxalicum(PSF4) selected for evaluating their Phosphorous solubilization from PVK Broth Ca3(PO4)2 as inorganic phosphate. Hence to test amount of released phosphorus(P) in PVK broth were increased over time for most of the bacterial isolates. However, for Pseudomonas aeruginosa (PSB2) due to this 12.78±0.15,33.19±0.3 and 43.40±0.26µg ml-1 for days after incubation 5,10 and15DAI respectively.Thus, the amount of P-release was slightly not efficient while comparing with other isolates.Thus, Pseudomonas fluorescens(PSB1)exhibited the highest phosphorus release in the broth at 68.91±0.19,103.91±0.37,and 122.13±0.29 µg ml-1 on days 5,10,and 15 after incubation respectively. The release of P from PVK Broth increased slightly after 5DAI, with solubilized P levels varying by PSF1, PSF2, PSF3 and PSF4, respectively. Study reveals that PSB isolates inoculated pots significantly increased shoot compared to the control (n=3,p < 0.05) 55.03±0.45cm(RP+PSB1). The PSFs the best results the highest shoot length TCP+PSF2(62.6±1.6cm).The study compares the RP with PSBs and PSFs shows the highest root length RP+PSB1 and RP+PSF2 showing 8.4±0.28cm and 8.5±0.28cm respectively. As well as PSF2 +TCP which was 7.9±1.6cm. The result shows the highest level of phosphorus utilized by plant shoot by each treatment was observed with TCP+PSB2 (74.65 ppm), TCP+PSB1 (69.18 ppm) and TCP+PSF1 (63.96 ppm).The study revealed that the concentrations of soil P-solubilized by TCP+PSB1 and TCP+PSB2 were gradually high,reaching 46.43ppm and 36.92 ppm, respectively. Therefore,the PSB and PSF isolates would be promise to increase agricultural output without depending on chemical fertil