Conventional breeding of Pacific Island staple crops: A paradox

Abstract

The Pacific Islands (Melanesia, Micronesia, Polynesia) were the last region in the world to be colonized by modern humans. In their migrations, they dispersed asexually propagated food plants that were first domesticated in Melanesia and exposed them to further selection in diverse insular environments. Later, staple food crops were introduced from South America. In our search for research on genetic resources characterization and breeding conducted between 1950 and 2022, we retrieved 338 references on 13 crop species. All studies were examined, and a review is presented here. Relatively few were on genetic improvement (92 references) compared to those on morphological diversity (246 references). The paradox is that the Pacific is considered a region exposed to the climatic crisis, perhaps more vulnerable than any other region in the world. This paradox is surprising when we consider that most people in the Pacific are growing staple food crops, for household use and/or for local markets, and occasionally for export. In some countries, it involves more than 75% of the population with a considerable contribution to gross domestic product (GDP). Plant breeding has not been considered a priority to mitigate against forthcoming changes in climate, which is likely to be detrimental to crops with a narrow genetic base. We suggest several possible reasons and that conventional plant breeding should be given high priority based on new approaches that include geographical distribution of allelic diversity.