Taxonomy and new collections of wild potato species in central and southern Peru in 1999

Peru contains about half of the described wild potato taxa, and many of the se are not yet preserved in genebanks. This paper reports results of the se cond of a series of five planned collecting expeditions to Peru. Collection s were made in the central Peruvian departments of Ancash, Huancavelica, La Libertad, and Lima, from March 8 to April 25, 1999. They follow collection s in 1998 in the southern Peruvian departments of Apurimac, Arequipa, Cusco , Moquegua, Puno, and Tacna. me collected 101 germplasm accessions, includi ng first germplasm collections of the following 22 Solanum taxa: Solanum am ayanum, S. anamatophilum, S. arahuayum (lost in germplasm increase), S. aug ustii, S. bill-hookeri, S. cantense, S. chavinense, S. chomatophilum var. s ubnivale, S. chrysoflorum, S. gracilifrons, S. hapalosum, S. huarochiriense , S. hypacrarthrum, S. jalcae, S. moniliforme, S. multiinterruptum f. longi pilosum, S. multiinterruptum var. machaytambinum, S. peloquinianum, S. rhom bilanceolatum, S. simplicissimum, S. taulisense (lost in germplasm increase ), and S. wittmackii. In addition, new collections were made of the under-c ollected species S. hastiforme (three collections). The above taxonomy is t hat used in planning our expedition, that we compare to a new treatment of Peruvian wild potatoes published by C. Ochoa in 1999. This paper reports th e collection and new species identifications of the 1999 collections, and g ermplasm conservation and survival of the 1998 and 1999 collections. In add ition, chromosome counts are provided for 134 accessions from the 1998 and 1999 expeditions, including first reports for S. chomatophilum var. subniva le (2n = 2x = 24), S. megistacrolobum subsp.purpureum (2n = 2x: = 24), and S. multiinterruptum var, multiinterruptum f. albiflorum (2n = 2x = 24); we also report the first triploid count of an accession of S. immite.