Accelerated breeding using molecular markers
The increasing world population, changes in climatic conditions, the emergence of new diseases in certain regions, as well as competition among manufacturers of seeds and planting material, have put a huge pressure over the institutes and companies in the need to create new and more productive varieties. Unfortunately, the pace of new varieties creation through classical methods of breeding is considerably slower than the growing need for putting into practice of new ones.
The acceleration of the breeding process nowadays is carried out using molecular DNA markers. In recent decades, our knowledge about the genes and the function of the proteins they encode in a number of model and economically important plant species increased significantly, leading to the possibility of predicting the characteristics of a plant even before it has grown and has manifested them.
Genetic maps have been developed for a number of agricultural species and genome areas which determine important economic traits have been mapped as well as specific DNA markers associated with these traits have been identified. It is no longer necessary to wait years before the plants derived from the cross-pollination can be assessed. In this case, the plants can be analyzed at an early stage (eg. seedlings) for the presence of DNA regions with particular sequence, which determine the desired by the breeder qualities. Only those, which carry the respective DNA markers are retained for growing to mature plants.
Thanks to the use of DNA markers in modern breeding, the costs of maintaining large populations in the breeding process are largely reduced, while at the same time, the time required for breeding of a new variety is drastically decreased. As a disadvantage, one may highlight the need for prior identification of molecular DNA markers associated with particular traits in the respective plant species before their routine application for breeding is possible. While such markers have been identified for a number of economically important plant species, for many other species, studies are still missing or are at an early stage of development.