Breeding disease resistance

Most early efforts in flax improvement in North America were aimed at breeding disease resistance (Kenaschuk and Rowland, 1993), and the most practical method of controlling disease remains the development and use of resistant varieties, combined with effective crop rotations. 

Maintenance of conditions ia the culture environment that keep stress to a minimum is one of the best methods of a voiding diseases. Vacciaes have beea developed agaiast several diseases and more are under development. Selective breeding of animals with disease resistance has met with only limited success. Good sanitation and disiafection of contaminated faciUties are important avoidance and control measure. Some disiafectants are Hsted ia Table 6. Poad soils can be sterilized with burnt lime (CaO), hydrated lime [Ca(OH)2], or chlorine compounds (12). 

Chemical treatment of diseases is not common, because of legislative controls and costs caused by the difficulty of appHcation through the leaf canopy. Breeding of resistant varieties is the main weapon for disease control. Some diseases, chiefly ratoon stunting disease, are controlled by hot water treatment of cane (6,8). 

Breeding Recurrent mass selection Adaptation to climate change Disease resistance Drought resistance Genetic diversity Salinity resistance Banilas et al. (2009) Carruba and Catalano (2009) Hejnak et al. (2009) Marais and Botes (2009) Martinez-Ballesta et al. (2009)... 

As genetic understanding develops, it will be incorporated into basic breeding programs that are concerned with such characteristics as yield, growth habit, insect and disease resistance, flavor, and texture. These programs will be most effective if present ambient ozone and other oxidant concentrations do not increase. 

Jansky, S. (2000). Breeding for disease resistance in potato. Plant Breeding Reviews, 19, 69-155. 

One of the advantages of using local breeds is that they are usually very well adapted to regional conditions. They are often better suited than modern breeds especially under harsh conditions. This could be also true for regions where particular breeds are not native (e.g. Brahman cattle in Australia). Local breeds can have some unknown properties or traits that will be important. They often have properties like disease resistance or longevity that are important for sustainable agriculture systems. Furthermore, rare breeds are part of the cultural history of the country of origin. 

Axford, R.F.E., Bishop, S.C., Nicholas, F.W. and Owen, J.B. (eds) 2000. Breeding for Disease Resistance in Farm Animals. CABI, Wallingford. 

The choice of breeds or strains should favour stock that is well adapted to the local conditions and to the husbandry system intended. Vitality and disease resistance are particularly mentioned, and preference should be given to indigenous species. 

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