ORIGIN OF THE FIRST EUROPEAN POTATOES AND THEIR REACTION TO LENGTH OF DAY

Abstract

AMONG the consequences of the recent Russian expeditions to South America was a revival of interest in the origin of the European potato. There are two centres from which potatoes might have come: the Chiloe region of South Chile, and the Andes at tropical latitudes. Bukasov¹ and his co-workers chose Chile, partly for morphological reasons which by themselves were insufficient, but primarily because the Chilean potatoes are adapted to long summer days, whereas the Andean potatoes are suited to the approximately twelve-hour day of the tropics and, as a rule, fare badly if grown in Europe during summer. But Salaman² pointed out that at the time when potatoes were known in Europe the Spanish hold on Chile was tenuous., and Magellan had not yet navigated the Straits ; it was unlikely either that the Spaniards could have acquired the potato in Chile or, if they had, that they could have brought it safely over the slow route home. On grounds of probability, it was much more likely that they took potatoes from Colombia, Ecuador, Bolivia or Peru., which had been conquered half a century earlier and which were in constant touch with Spain. On the question of photoperiodism, Hawkes! suggests in support of this hypothesis first, that the first European potatoes may have been long-day or day-neutral types, since these occur occasionally among Andean varieties ; secondly, that if they were short-day types, their character might have been changed by breeding, as Salaman² suggested earlier ; and, thirdly, that if they were short-day types, they might not have done too badly at the fairly low latitudes of southern Europe, to which they first came.