Heterosis in the Field: Why Hybrids Perform Better than Landraces

Heterotic responses of hybrid varieties lead to better performance of crops than conventional landrace varieties. Hybrids, which result from the known crossing of genetically distinct parent lines, are found to exhibit hybrid vigour in terms of increased yields, homogeneous growth, and the ability to resist biotic and abiotic stress factors. Landraces are locally adapted varieties that have been farmer chosen and provide the elements of genetic diversity, low-input resilience and cultural importance. Hybrids work best in commercial, high-input forms of farming, but landraces are still significant in marginal areas as well as sources of future breeding material. The maintenance of a balance in the seed choice, i.e. productive seed like hybrids and conservation seed, which are landraces, can increase the sustainability of the farms. Realising the strengths and weaknesses of the two kinds of varieties will enable the farmers to make informed choices that are suitable to their agro-ecological location, availability of resources and production objectives.