Inoculation of maize with phosphate solubilizing bacteria: effect on plant growth and yield

Abstract

Phosphate-Solubilizing Bacteria (PSB) improve plant growth, yield and phosphorus content of several crops, and may be used as bioinoculant to enhance sustainable production. We evaluated the response of maize (Zea mays L.) to PSB inoculation under controlled and field conditions in Tucumán, Argentina. A pot culture experiment was conducted to investigate the effects of seven previously isolated PSB on early development of plants. Seeds were treated with each bacterial strain, and seedlings were harvested 30 days after inoculation. All strains showed a positive effect on plant growth. A significant increment in plant height (45%), shoot dry weight (40%) was determined in plants treated with Pseudomonas tolaasii IEXb, while Pseudomonas koreensis SP28 has remarkably increased P content compared to the uninoculated control. IEXb strain was selected and evaluated under field conditions in combination with triple superphosphate (TSP) as P fertilizer. The presence of IEXb strain stimulated seedling emergence (8%), shoot length (19%), grain yield (44%), 1000-grain weight (18%), total dry biomass (32%) and P content (56%) of maize plants. In general, P. tolaasii IEXb inoculation was more efficient as bioinoculant without P fertilizer than with TSP. These results provide baseline information for future studies of P. tolaasii IEXb as bioinoculant to promote an eco-friendly and sustainable agriculture.

Effect of phosphorus, organic and biological fertilizer on yield of mungbean (Vigna radiata) under two cropping patterns

“…Similar report by Walpola and Yoon (2013) that Co-inoculation of both PSB and P fertilizer exhibited the highest growth performances of mung bean. Enhanced plant growth after inoculation of PSB can be attributed to the ability of the bacteria to make P available for plant uptake and to produce plant growth-promoting substances (Linu et al, 2009;Viruel et al, 2014). A similar increase in growth of mung bean plants due to inoculation of PSB was observed by Walpola and Yoon (2013) and Rani et al (2016).…”

Phosphorus acquisition of wheat, pea and narrow-leafed lupin under different P supplies

“…On the other hand, crop differences in acquiring P could be attributed to the interaction with different plant growth promoting rhizobacteria, microorganisms interacting with plants in several ways (Vessey et al, 2003). For instance, phosphate-solubilizing bacteria (PSB) are rhizobacteria that convert insoluble phosphates into soluble forms through acidification, chelation, exchange reactions and the production of organic acids (Viruel et al, 2014). There are no studies in wheat, pea and narrow-leafed lupin comparing the importance of root exudates and/or their interaction with PSB in order to acquire P, which would allow us to explain possible differences among these species in relation to this topic.…”

Phosphate solubilization by fungi with nematicidal potential

“…Nonetheless, these characteristics could be more related to the production of phytohormones and growth-promoting substances than to phosphorus solubilization (Narloch et al, 2002). A better indicator of the effect of phosphate solubilization on plants by a microorganism is to evaluate the variables related to phosphorus uptake, such as the numbers of flowers, fruits or seeds (Bashan et al, 2013;Viruel et al, 2014). We recorded a slight increase in the number of seeds in oat plants in the treatment with P. carneus, which may be directly related to the increase in available soil phosphorus (El-Azouni, 2008;Malviya et al, 2011).…”