Breeding grain crops to increase adaptability

The most essential feature of promising varieties is their adaptability, i.e., an ability to withstand environmental effects, which reduce productivity. Adaptation under plant-environment interaction, and the use of self-regulation mechanisms of yield formation and habitat-forming environmental processes influenced by plants take a central place in the evolution theory and plant breeding (Z.V. Andreeva et al, 2014). The review considers the adaptive potential of grain crops and the main concepts, characteristics and tasks of plant breeding for adaptability. The purpose of such breeding is to obtain the varieties with high resistance to unfavorable conditions. The concepts of stability, plasticity, homeostasis and resistance to stressors are discussed. In a broad sense, the genotype-environment interaction reflects plant response to any changes of the environment. In a narrower sense, the concept is used to describe the productivity change of genotypes in different environmental conditions. This interaction is crucial to increase crop production. The interactions and interrelations of genotype and environment are various and complicated. They greatly depend on genotype and a factor chosen as environmental agent or conditions (V.A. Zykin et al, 2005). A slight difference between genotypic potential and its phenotypic manifestation indicates a less response of a particular genotype to the environmental factors. Various methods are helpful to identify potential productivity and adaptability of the varieties. The estimates of adaptability and plasticity allow to determine reliably the differences among breeding material and gives an additional information to select valuable parental forms possessing adaptive traits. Special breeding methods which depend on environmental conditions and a phase of plant ontogenesis are necessary to create crop varieties and hybrids that have a good adaptability (A.P. Golovchenko, 2001).