Potato microtuber production and performance: A review

Almost half a century has passed since in vitro tubers (microtubers) were first described in Potato, but their adoption as a seed propagule has been uneven globally. Consensus is lacking regarding optimal production practices for microtubers and their relative productivity in relation to other propagules for minituber production. There is significant uncertainty regarding the utility of microtubers for evaluation of agronomic characters. However, the application of microtubers in germplasm conservation is widely accepted. Microtubers are produced in vitro in a plethora of different growing systems with varying environment, media constituents, and storage intervals. Many of the interactions between growth parameters in vitro and subsequent productivity appear to be genotype-specific. Accordingly, microtubers come in different sizes, have different dormancy requirements, and differ widely in relative growth potential and productivity. Despite these differences, there is evidence for strong analogies in growth responses between field-grown tubers and microtubers. The use of microtuber technology in seed tuber production, breeding programs, germplasm conservation, and research appears to have enormous potential. This review discusses microtuber production, yield and performance, in vitro screening, and germplasin storage and exchange.