Biosolubilization of phosphorus from rock phosphate and other P fertilizers in response to phosphate solubilizing bacteria and poultry manure in a silt loam calcareous soil

Abstract

‘Phosphate solubilizing bacteria' (PSBs) are able to release unavailable P from native and applied P sources into plant‐available soil pool through their solubilizing and acidifying effects. The effects of three indigenous and one exotic PSBs on P solubilization from different P sources, plant biomass production, and P‐uptake efficiency of maize (Zea mays L.) were examined in an incubation and greenhouse study. For incubation study, surface (0–15 cm) soil was collected from an arable field (Inceptisols) and amended with rock phosphate (RP), single superphosphate (SSP), poultry manure (PM), and RP+PM with and without PSBs. The amended soil was incubated in the control environment at 25 ± 2°C for a total of a 100‐d period to establish relative potential rate of P solubilization of added P sources. A complementary greenhouse experiment was conducted in pots by growing maize as a test crop. Growth characteristics, P‐uptake, and P‐utilization efficiency (PUE) were determined. Phosphate solubilizing bacteria generated a solubilization effect on different P sources by releasing more P into plant‐available soil pool, i.e., 14.0–18.3 µg g−1 in RP, 5.0–9.9 µg g−1 in SSP, 1.4–4.4 µg g−1 in PM, and 4.5–7.8 µg g−1 in RP+PM compared to their sole application without PSBs. The available P from inorganic SSP declined continuously from the mineral pool (after day 30) and at the end 40% of applied P was unaccounted for. However, P losses were reduced to 28 and 27% when PSBs (PSB1 and PSB3) were applied with superphosphate treatments. In the absence of PSBs, the recoveries of applied P (in soil) from RP, SSP, PM and RP+PM were 4, 25, 9, and 12%, respectively, those had been increased to 14, 30, 12 and 15% in the presence of PSBs. Similarly, the plant biomass in RP+PSBs treatments compared to the RP without PSBs increased between 12–30% in first sampling (30 DAG) and 13–30% in the second sampling (60 DAG). The P utilization efficiency (PUE) in plants supplemented with PSBs was 20–73% higher compared to those without PSBs. The detection of oxalic and gluconic acids in culture medium treated with PSBs (7.8–25.0 and 25–90 mg L−1, respectively) confirmed the production of organic acids by the indigenous bacterial isolates. This study indicate that low P recovery both in plant and soil can likely be improved by using indigenous PSBs and organic amendment poultry manure, which allowed a more efficient capture of P released due to P solubilization.

Inoculation with rhizobacterial consortia alleviates combined water and phosphorus deficit stress in intercropped faba bean and wheat

“…Such changes would suggest that membrane stability is affected and that these structures would no longer function properly. Another study conducted by Abbasi and Manzoor (2018) showed that the RWC of wheat plants decreased under P deficiency and salt stress. For the same species, the combination of water and salt stress highly affected the genes that are responsible and related to growth and different trait indicators of nitrogen metabolism (nitrogen content, stable nitrogen isotope composition, glutamine synthetase, and nitrate reductase activities) and photosynthetic carbon metabolism (Yousfi et al, 2016).…”

“…The application of RP seems to be an affordable and environment-friendly solution to replace chemical P fertilizers. Additionally, the application of organic fertilizers often did not show the same positive effects as mineral fertilizers (Abbasi and Manzoor, 2018). The utilization of phosphate-solubilizing bacteria (PSB) in combination with RP could increase the level of plant-available P in soils (Wahid et al, 2016).…”

Use of Mineral Weathering Bacteria to Enhance Nutrient Availability in Crops: A Review

“…In vitro investigations of microbial weathering have demonstrated that the solubilizing ability of PSB and KSB is mainly affected by factors such as the concentration of soluble P or K, C and N sources, and pH (Parmar and Sindhu, 2013;Musarrat and Khan, 2014). In the same way, soil experiments and field trials indicate that N fertilization, organic amendment, and lime addiction directly influence the effectiveness or abundance of solubilizing organisms (Adnan et al, 2017;Zheng et al, 2017;Kaleem Abbasi and Manzoor, 2018;Zheng et al, 2019). Therefore, these factors can be modulated to enhance bacterial solubilization of minerals.…”

“…Since the first reports of 70 years ago, PSB benefits have been demonstrated for different and agronomically relevant crops. The main observed effects in crop production include the reduction in the application of traditional fertilizers (Sundara et al, 2002), the improvement on the efficacy of low-cost RP, the reduction of P losses in the soil, and the improvement of plant development (Kaleem Abbasi and Manzoor, 2018). In Table 1, different studies were summarized considering the concomitant effect of PSB inoculation with the RP soil amendment.…”

Will Phosphate Bio-Solubilization Stimulate Biological Nitrogen Fixation in Grain Legumes?

“…The role of PSM such as bacteria and fungi in increasing soil P available fraction has been widely investigated by many researchers (Manzoor et al, 2017;Adhikari and Pandey, 2019;Faried et al, 2019). Phosphate solubilizing bacteria are the most known and studied microorganisms for their potential to solubilize P. These microbes participate in bio-geochemical P cycling mainly through solubilization of inorganic forms of P and mineralization of organic ones (Manzoor et al, 2017;Abbasi and Manzoor, 2018). The microbial solubilization of insoluble P has been often attributed to organic acid excretion (i.e., lactic acid, succinic acid, acetic acid, fumaric acid, etc.)…”