Disease Management
Disease Spread
Magnaporthe oryzae is spreadnaturally from plant to plant within a field and from field to field within a regionthrough the forcesof wind and rain. This is
how most epidemics develop. M. oryzae can also be spreadfrom field to field within a region and from region to regionas a result of human activities, including the movement of farm machinery or seeds infected/infested with the 1xbet online games login pathogen from an infested field to uninfected fields.Movementof infected/infested seedsis the most likely mechanism for thespread of 1xbet online games login from the original outbreak site in Brazil to other parts of Brazil and to Bolivia and Paraguay. 1xbet online games login could be introduced into the U.S. as a result of increased trade and travel between the U.S. and Brazil.
1xbet online games login could alsoemerge in the U.S. as a result of the evolution and establishment of new strains of M. oryzae from indigenous populations on grass species. 1xbet online games login pathogens may have already emerged in U.S. on other hosts but environmental factors haven’t yet favoredoutbreaks/epidemics.
Host Plant Resistance
1xbet online games login is currently managedby planting wheat varieties selected for some level of resistance to M. oryzae. Although an important component of a blast management plan, to date host plant resistance has not been adequate as a stand alone strategy. Even with "resistant" varieties, the application of fungicides is necessary during epidemic years in order to prevent substantial yield loss. The search for effective and durableresistance is underway in Brazil, Bolivia, Paraguay andat CIMMYT(the International Maize and Wheat Improvement Center in Mexico).Plant genotypes with immunity have not yet been identified.However, research at Kansas State university and at the USDA ARS Lab at Fort Detrick MD has identified wheat varieties with very high levels of resistance.The durability ofthat resistance needs to be determined.
Avoidance
In Bolivia and Brazil, wheat blastoutbreakscan be significantly reducedbydelaying the planting date to avoid infection. This has been effective except in El Nino years when temperatures and rainfall favor spread of the pathogen anddisease development.
Fungicides
As with any plant disease,successful managementof 1xbet online games login with fungicides requires the application ofan effective chemistry at the right dose, at the right time, andusing the right equipment (e.g., spray nozzles). 1xbet online games login ismost effectivelymanaged with a combination of timely applications of preventative fungicides and the planting of wheat varieties with some level of resistance.
