Abstract
Aspects related to the breeding of quinoa for increased tolerance against frost, drought, and salinity are presented with special emphasis on the conditions existing in the Peruvian Andes. Evidence from the literature indicates that plants' responses to these stresses are essentially similar, and the physiological processes involved are interrelated. The evidence suggests that tolerance to abiotic stress is polygenicallyinherited, justifying the application of appropriate plant breeding methods. A compilation of meteorological studies is presented that can be used to define the specific climatic phenomena of night frosts occurring in the quinoa-growing region of the Andes and to specify the conditions for selection of tolerant varieties. A composite-bulk breeding scheme is proposed that could be useful for highly efficient breeding of quinoa varieties. Possible future application of molecular-marker-assisted selection is discussed.