Similar to the challenge associated with BPMV, there are few known sources of natural resistance against AMV in soybean (Crop Sci. 48:933). We have unequivocally established the seed transmissibility of AMV in soybean. This is important since AMV infected seed could serve as an inoculum source for spread of soybean-adapted variants to a new area. The antibody-based ELISA method developed in the laboratories of Drs. Hill and Grau for finding sources of resistance against BPMV and SMV by screening seeds collected from field-grown soybean plants is likely applicable to AMV.

However, the major limitation in application of this approach to AMV was lack of a suitable immunoassay. Suitable antibodies against AMV were produced that can easily detect a variety of virus isolates in infected plants. The results pertinent to these antibodies are published. Methods for extraction of seeds for the ELISA were determined in order to maximize the sensitivity of the assay. However, screening of soybean seeds for the presence of virus is awaiting availability of adequate seeds collected from AMV infected fields. These seeds are going to be produced in the current growing season.

For field testing of plants for resistance screening, it was determined that for North Central producers samples should consist of pooled trifoliolate leaf samples taken 30 - 60 days after infection. Symptomless infection can occur which means assessment of resistance and/or seed transmission based on field symptoms is problematic.