|
APSnet Education Center Advanced
Topics | Return
to the Topics Index Cultivar Mixtures
Ariel Castro High crop yields are a principal objective of modern agriculture. Plant breeding has achieved high crop yields through hybridization and selection of superior plants. These superior types are often grown in monocultures where each plant is genetically identical to its neighbor. The genetic uniformity for plant height, maturity, and quality characteristics also facilitates harvesting, marketing, and processing of the crop. Wheat, maize, rice, potatoes, soybeans, and banana are some crops that are typically grown in monocultures.
A negative consequence of genetic uniformity is an increase in genetic vulnerability to disease caused by microbial pathogens. Plant diseases can prevent a crop from achieving its yield potential, and the cost of disease and its prevention can dramatically affect the economics of crop production. If genetic uniformity makes a crop more vulnerable to disease, then one potential, low cost method of suppressing disease is to increase the genetic diversity of the crop. A simple way to enhance genetic diversity is to mix the seed of cultivars (i.e. plant genotypes) that vary in their susceptibility to specific pathogens. This method ensures genetic diversification with the advantage that it can be used in addition to any other form of disease control (Wolfe 1988). This unit describes theoretical, experimental and practical results obtained using mixtures of crop cultivars for disease suppression. The information is targeted at students who have had or are currently enrolled in an upper division or graduate level class in plant pathology. |
| ||
Copyright © 2007 by The American Phytopathological Society |
