Crop diversity are all susceptible to a single fungus, "Fusarium oxysporum" (Panama disease); large areas of the crop were destroyed by the fungus in the 1950s. 'Gros Michel' has been replaced by the current main banana on the market, the 'Cavendish', which in turn is (2015) at risk of total loss to a strain of the same fungus, 'Tropical Race 4'. Such threats can be countered by strategies such as planting multi-line cultivars and cultivar mixes, in the hope that some of the cultivars will be resistant to any individual outbreak of disease. The implications of crop diversity are at both local
High plains disease for the wheat curl mite. High plains disease also may occur on barley, oats and rye, and on drooping brome "Bromus tectorum" and yellow foxtail "Setaria pumila" grasses. An ELISA test is available to detect high plains disease. Infection can be avoided by elimination of volunteer crop and wild host plants prior to planting. Resistant varieties of maize exist. High plains disease High plains disease is a viral disease afflicting wheat and maize. It is caused by the negative-sense ssRNA virus wheat mosaic virus. Symptoms are similar to wheat streak mosaic virus, with leaf veins showing yellow flecks and streaks,