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Location: Crops Pathology and Genetics Research

2010 Annual Report

1a. Objectives (from AD-416)
Objectives are as follows: 1)Evaluate the impact of microbial inoculants on the incidence and severity of soilborne disease and on the overall health and vigor of bedding plants; 2)Evaluate the effect of adding pheromones to sticky traps on ability to monitor/detect thrips populations and for the potential to reduce thrips populations and the resultant damage on a variety of ornamental crops; 3)Evaluate the addition of silicon to ornamental crops to reduce damage by insects and mites and to produce healthier and more vigorous plants; and 4)Transfer effective new technologies to appropriate customer/stakeholder groups.

1b. Approach (from AD-416)
1) Through a series of research/demonstrations, will evaluate the relative performance of a variety of microbial inoculants compared to normal grower practices; 2)in cooperation with growers in California, will evaluate the use of pheromone/sticky traps on control of thrips in a commercial greenhouse; 3)in cooperation with growers, will run side by side comparisons of plants grown with and without the addition of silicon to determine if adding silicon to ornamental plants will increase their ability to resist attack insects and diseases and produce healthier and more vigorous plants; and 4)will develop a Bedding Plant/Plant Propagators Alliance. Via meetings of this Alliance, will complete a Crop Profile for bedding plant producers and plant propagators. Documents SCA with UC Davis.

3. Progress Report
The agreement was established by S. Schneider in FY2008 for a three year SCA associated with FNRI research, the goal being to develop and implement integrated pest management for bedding plants. The goal of this project is to evaluate the impact of microbial inoculants on the incidence and severity of soilborne disease and on the overall health and vigor of bedding plants. Efficient Microorganisms (EM-1) & EM Technology are currently used in a wide range of applications in more than 100 countries on six continents. The use of this product in the US is limited, and efforts are underway by the company to expand into the US market. The concept of EM is based on the inoculation of mixed cultures of beneficial microorganisms into the system where they shift the microbial equilibrium back to a normal, healthy state. In general a series of inoculations are needed to reestablish this balance. Focusing on the floriculture/nursery industry in CA, we initiated a series of experiments to evaluate the ability of EM-1 AEM (activated EM) to reduce plant pathogens after colonization in the rhizosphere. It also appears that these materials have the potential to reduce pathogens in irrigation water via direct injection and this was also evaluated. Our first experiments reported here addressed the latter question. Both EM1 and AEM provided control of Phytophthora capsici and Fusarium oxysporum, although there were notable differences in observed control between products, pathogens, exposure times, and dilutions. In addition, the products impacted P. capsici much more than they did F. oxysporum. In the P. capsici trials, longer contact times were needed in the second trial than in the first to achieve comparable reductions in survival for both EM1 and AEM, although by 4000 minutes in both trials all treatments showed less survival than the control. This is most likely due to the higher initial pathogen level in the second trial (3.2 x 101cfu/ml in the first trial vs. 6.9 x 101cfu/ml in the second). There was a trend with both EM1 and AEM for higher concentrations of product to result in reduced P. capsici survival. In a set of separate experiments we examined whether the pH value or EC levels of the EM-1 and AEM solutions may also have affected the results of these trials. While both these variables impacted pathogen survival, they could not fully explain the treatment differences. There was a trend for greater reductions in survival to be caused by EM-1 compared to AEM at the same concentration and contact time. It is not clear from these experiments whether this is due to the activity of EM-1 or AEM, solution pH or EC, or an interaction of several factors. From our preliminary work, it appears that a concentration of 1:500 for both the EM-1 and AEM products provided better root growth and stronger plants, so this is the concentration we will use when we begin the Phytophthora control trials in hydroponic recirculating systems. The ADODR monitors this SCA by maintaining a complete file of the agreement, reviewing the annual reports, and conducting meetings with the cooperator during the course of the agreement.

4. Accomplishments