Limitation of Drought Resistance Plant Breeding

Limitation of Drought Resistance Plant Breeding

Breeding for drought resistance has several advantages. It helps in extending cultivation of several field crops in drought prone areas. Drought resistant varieties are more stable to environmental fluctuations and are expected to stabilize crop production under conditions of water stress. Thus, drought resistance breeding is useful in many ways. However, there are some limitations of drought resistance breeding which are given below:

1. Breeding for resistance to various types of stress generally leads to reduction in yield due to strict selection pressure for resistant genes. Breeders are fortunate if any drought resistant line is equal to the best parent in yield. sometimes, simply inherited characters associated with stress resistance have adverse effect on yield potential.

2. In Spring wheat, a cultivar which gave the highest yield under normal moisture level gave lower yield than many cultivars where grown under drought conditions ( Hurd, 1969). Thus selection for wide adaptability is a selection for medium or even low yield. (Rutz, 1975).

3. Genes for drought resistance are mostly found in the germplasm lines which are generally unadapted types. Utilization of unadapted lines poses problems of linkage between desirable and undesirable characters.

4. In some cases, the drought resistant genes are available in the wild species. Transfer of resistant genes from wild sources poses several problems such as hybrid inviability, hybrid sterility and linkage between desirable and undesirable genes.
This greatly reduces the chances of obtaining desirable combination of favourable genes.

5. Breeding for drought resistance requires cooperation among geneticist, breeder and crop physiologist.