Improvement of performance of introduced varieties over generations is called:
Acclimatization describes gradual adaptive improvement in performance of introduced variety over successive generations grown in new environment. Initially introduced genotype may flower late, show asynchronous maturity or susceptibility to local leaf rust races. Continuous natural and farmer selection favours individuals with favorable alleles for photoperiod insensitivity, thermal tolerance, efficient nutrient uptake and pathogen defense mediated by polygenic QTL. Epigenetic modifications such as DNA methylation changes altering gene expression without sequence change also contribute. Over t
Ref: Allard RW Principles Plant Breeding Acclimatization chapter; e-courses Breeding Fruit Crops Acclimatization; FAO Adaptation.
