offspring. Management The best way to control the virus is to plant with clean seed, since the virus is spread through infected seed. BMSV is also spread through mechanical transfer of the virus; reducing handling and movement through infected areas will help contain the disease. Sterilization of all tools and machinery, specifically irrigation systems, used in fields will reduce the spread of BMSV. Quaternary ammonium salts and hydrogen dioxides are two common commercial products used for sterilization of horticulture tools and machinery. Removal of infected plants can help reduce the spread of the virus. In fields where the disease has gone unnoticed, allowing the virus to spread, it is important to prevent spread to other fields and prevent seeds from infected plants from being planted the next year, as they too are likely infected with virus. Chemical control and biological control are not known to exist for this virus. Host plant resistance is another form of management. Barley hosts differ in their susceptibility to BSMV. There are many types of resistant barley varieties including: Traill, Moreval, Modjo-1, Morex, Modjo, and CI 4197. Importance One study has found that the BSMV resistance gene shows Mendelian genetics and has shown to be dominant by complete mapping of the Bsr1 Barley Stripe Moasic Virus Resistance Gene in Brachypodium distachyon. Barley Stripe Mosaic Virus is one of the very few viruses that is transmitted through seeds for small grain cereals. BSMV mostly affects regions in Montana and North Dakota and have reduced yields by up to 25%. Shortly after its discovery, BSMV was found to be present in 97% of barley fields in North Dakota in 1954. To combat this, in 1957 Kansas, Montana, and North Dakota launched a seed certification program to obtain BSMV free barley seeds. The control program involved assaying seedlings for presence of the virus, and only seed foundations determined to be BSMV-free were used to produce certified BSMV-free seeds to be sold commercially. By 1972 a zero tolerance was placed on all certified seeds in Montana which led to a dramatic decline in yield loss due to BSMV. Similarly, in 1971 BSMV was eliminated in barley seeds in North Dakota. However, despite not being a factor in crop production anymore, BSMV is still important in research, as various studies have shown that it can be used to study gene function via gene silencing in oat, wheat, and Brachypodium distachyon