Farm-Grown Microbial Soil Inoculants: Effects on Bread Wheat Yield and Quality

Farm-Grown Microbial Soil Inoculants: Effects on Bread Wheat Yield and Quality

Summary

The aim of this project is to evaluate the efficacy of two on-farm produced microbial inoculants and one commercially available inoculant on organic bread wheat yield and quality. A prominent Maine organic farmer asked us to test a purchased inoculant that he uses in wheat (MycoApply from Mycorhizzal Applications Inc.). In addition we are evaluating two emerging on-farm inoculant production methods: one developed by USDA-ARS researchers for arbuscular mycorrhizal fungi (AMF) (Douds et al 2005), that has shown positive results in vegetables and fruit (Douds et al 2007 and 2008); and one based on a South Korean practice of culturing indigenous microorganisms (IMO) from local organic matter and soil (Park and DuPonte 2008; Prell 2010). AMF, IMO, MycoApply® and relevant controls are being tested in greenhouse and field trials for their effects on bread wheat growth, nutrient uptake, yield and grain quality.

We are also evaluating the production methods, costs and returns associated with producing on-farm inoculants. Outreach includes a fact sheet, presentations at field days and hands-on workshop. This project will help farmers evaluate whether to use microbial inoculants and whether on-farm production of inoculants is appropriate for their farm. It addresses the sustainable agriculture goals of fostering healthy soil and productive crops while reducing off-farm inputs and maximizing on farm resources.

Objectives/Performance Targets

1) Evaluate the effects of 2 farm-produced and 1 commercially available microbial soil inoculants on bread wheat yield, and grain quality through field and greenhouse trials.

a) Preliminary field trial completed in August 2011; tested all 3 inoculant treatments and their relative controls.

b) Greenhouse trial testing all 3 inoculants and their relevant controls scheduled to begin January 15th, 2012 in the University of Maine Roger Clapp Greenhouse.

2) Evaluate the costs and returns associated with producing and using the different inoculants.

a) Records kept of expenses from inoculant purchase or production and application.

b) Assessment of relative returns due to inoculant treatments to be accomplished when data analysis from field and greenhouse trials is completed.

3) Provide results to farmers through a factsheet, presentations at field days and conferences, and a hands-on workshop.

a) Presentation of preliminary field trial at University of Maine Sustainable Agriculture Field Day at Rogers Farm; July 11, 2011.

b) Additional discussion and sharing of SARE project research on microbial inoculants with farmers from the local and global community. (Details Section 4)

Accomplishments/Milestones

Beginning with a preliminary field trial in May and ending with planning the 2012 winter greenhouse trial, 2011 has been productive. Overall the research project has progressed as scheduled and according to plan. IMO 4 was successfully made twice in Orono, Maine in June and October (Figure 1). Specific accomplishments and lessons learned in the field and greenhouse trials are detailed below.

FIELD TRIAL:

A preliminary field trial was planted in May 2011 at the University of Maine Rogers Research Farm with Spring Wheat (variety Glenn). The preliminary trial and results, which are forthcoming, will be used to design the project field trial in 2012.

GREENHOUSE TRIAL:

-Scheduled starting date: January 15th, 2012.

-Fall of 2011: experiment planning, design and protocol development.

-Supplies ordered, collected and made: containers and soil media for growth, Glenn wheat seed, inoculants for treatments, clover for cover-crop simulation, organic fertilizer to ensure adequate fertility, and data loggers and sensors for monitoring environmental conditions.

-Grow lights and greenhouse space secured in University of Maine’s Roger Clapp Greenhouse. Bench light patterns have been monitored to create uniform light conditions within each of the 6 blocks/repetitions of the randomized experiment. Treatments within blocks will be rotated to further ensure even light distribution.

-First two weeks of January 2012 will be busy preparing for the start of the Greenhouse trial. An undergraduate worker has been hired to help the project leader mix soil, fill, seed and water containers, rotate containers within blocks, collect data, and other project tasks.

• Aaron Englander, project leader, making IMO 4 in Orono, Maine October, 2011.

Impacts and Contributions/Outcomes

The goal of the research project is to investigate the efficacy of 3 selected microbial inoculants on bread wheat and help farmers assess the applicability of such inoculants for their agricultural systems. By empirically assessing the inoculants we hope to gain a greater understanding of their effects upon wheat growth, nutrient uptake, grain quality and nutrient availability in the soil. This information can help inform farmers, gardeners and others how to use these inoculants and lead to further questions and research about the most effective, efficient applications for microbial inoculants in agriculture.

Outreach in 2011 included:

– Presentation of research at University of Maine Sustainable Agriculture Field Day held at Rogers Farm in July.

– Participation in discussion at MOFGA Farmer to Farmer Conference in November on microorganisms and their effect on soil organic matter.

-Sharing IMO production methods and information about research with Maine organic farmer and artisan bread baker from Backyard/Farmyard (http://backyard-farmyard.com/) Collective.

-Communication with A Growing Culture (http://www.agrowingculture.org/) and Camino Verde (http://www.caminoverde.org/) about the SARE project on soil microbial inoculants.

While the research project is relatively new, it has generated interest amongst local and global farmers and agriculturalists. This may reflect a burgeoning interest in the use of microbial inoculants and biofertilizers in modern agriculture to reduce reliance upon purchased inputs. For instance Robin Van Loon of Camino Verde said “IMO’s and the like are a kind of next frontier in agriculture” (Personal communication, 2011). Given the ecological impacts of farming practices, the current trends towards increased use of biological systems in agriculture such as microbial inoculants, may help maintain environmental integrity, locally and globally.

• Sources Cited

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