Researchers Create Inoculant Which Improves Corn, Tomato and Potato

06 Oct 2015 --- Researchers at the Benemérita Universidad Autónoma de Puebla (BUAP) have developed a microbial multi-species soil inoculant for plants which stimulates better absorption of their nutrients, reduces the occurrence of toxic substances and promotes the growth of corn, tomatoes, potato and rice, among others.

The project, which started in 2006, has dealt with six bacteria which reactivate the soil microbial population that has been affected by contaminants such as pesticides, herbicides and fertilizers used in agriculture and which also does not genetically modify the fruit.

The tests were conducted in the laboratory and suburbs in Tlaxcala, Hidalgo, Atlixco, Morelia, Veracruz and Puebla, where more nutritious and larger crops are available.

The formula, which has a patent from the Mexican Institute of Industrial Property (IMPI), contains beneficial bacteria that eliminate toxic compounds and produce inhibitory substances that protect against diseases, stimulate cell division and create a prominent root to acquire more nutrients, says Jesus Muñoz Rojas, a researcher at the Laboratory of Molecular Microbial Ecology, Research Center in Microbiological Sciences BUAP.

For several years different phyto-stimulating bacteria which produced inhibitory substances were selected, which are resistant to desiccation (lack of water), heat and cold. The result was the EMMIM-1 formula, composed of six bacteria: Gluconacetobacter diazotrophicus EPI 5T unamae MTL-641 Burkholderia, Bradyrhizobium sp. MS22, Azospirillum brasilense Sp7, Pseudomonas putida KT2440 and Sphingomonas sp. OF 178.

EMMIM-1 provides a natural communication between microorganisms and plants, called associative symbiosis. For example, one of the researcher says, the bacterium Pseudomonas putida KT2440 works like a vaccine. "It releases metabolites (organic compounds) which the plant detects and which protects it from pathogens that can infect it, like fungi."

Jesus Muñoz explained that the multi-species inoculant ensures its’ success. “If one bacteria does not work, another one comes in and reacts, so there is a greater chance that one of the six bacteria will assert its’ function.

Its use is simple; the seed is soaked in 250 milliliters of liquid form of EMMIM-1 and 250 of water, stirred and then allowed to dry: inoculated corn is used for planting one hectare. "When there is damp, the germination which activates the bacteria begins, which then travel down towards the roots.”

The research was funded by the Sectoral Innovation Fund (FINNOVA), the Ministry of Economy and CONACYT. The formula has had successful results in corn, beans, potatoes, tomatoes, lettuce, rice and several varieties of chili.

In addition, BUAP researcher says that crops absorb only 30 percent of the nitrogen fertilizer, the rest seeps into groundwater, which does not allow oxygen exchange. Also nitrogen oxide produces acid rain and affects the ozone layer; however, with multi-species inoculant the crop nutrients are better used and it contributes to reversing climate change.

The BUAP research group is also trying to create other multi-species formulations. They are currently patenting bacterium which are highly resistant to drought, stimulating the growth of plants in arid and semi-desert areas and which could increase the growth of endangered cactus.

"The future of agriculture must be healthy, organic, with the introduction of microorganisms that offer higher crop yield and healthy products which are free of toxic compounds"