International Potato Center

About: International Potato Center is a facility organization based out in Lima, Peru. It is known for research contribution in the topics: Population & Phytophthora infestans. The organization has 1036 authors who have published 1460 publications receiving 47183 citations.

Cultivation of Quinoa on the Peruvian Altiplano

Abstract: Quinoa cultivation in the Peruvian altiplano occurs under environmental conditions that change from year to year, including adverse climatic conditions such as drought, flooding, hail, and frost. Under such conditions, ensuring harvest security is crucial. Therefore, farmers plant quinoa throughout the various agroecological and physiographic zones of the altiplano to avoid losing their entire crop in a given year in a particular area (Morlon, [1982]). For the same reason, organization of the production of quinoa traditionally includes rotation with a mixture of quinoa cultivars as well as other crops such as potato, caniwa, field beans, and barley. Selection of cultivars is determined according to the climate, soil, and humidity of the location. The primary factor for organization of quinoa production is the agroecological zone. Each agroecological zone is divided into physiographic zones, which can be further divided based on specific environmental conditions.

Ecogeography of ploidy variation in cultivated potato (Solanum sect. Petota)

Abstract:  Premise of the study : The taxonomy of cultivated potatoes has been highly controversial, with estimates of species numbers ranging from 3 to 17. Ploidy level has been one of the most important taxonomic characters to recognize cultivated potato species, containing diploid (2 n = 2 x = 24), triploid (2 n = 3 x = 36), tetraploid (2 n = 4 x = 48), and pentaploid (2 n = 5 x = 60) cultivars. We tested the environmental associations of different ploidy levels in cultivated potato species that traditionally have been recognized as Linnaean taxa to see whether, in combination with prior morphological, molecular, and crossing data, some of the ploidy variants can be recognized as distinct taxa.  Methods : We summarize 2780 chromosome counts of landrace cultivated potatoes, provide georeferences to 2048 of them, and analyze these data for 20 environmental variables at 10-min resolution using the randomForest algorithm to explore associations with taxa and ploidy variants.  Key results : Except for the S. tuberosum Chilotanum Group and extreme northern and southern range extensions of the Andigenum Group, it is impossible to fidistinct habitats for the ploidy variants of the S. tuberosum Andigenum Group.  Conclusions : Our distributional and ecological data, in combination with prior results from morphology, microsatellites, and crossing data, provide yet additional data to support a major reclassifi cation of cultivated potato species. A rational, stable, and universally accepted taxonomy of this major crop plant will greatly aid all users of wild and cultivated potatoes from breeders to gene bank managers to ecologists and evolutionary biologists.

Etiology of Sweet Potato Chlorotic Dwarf Disease in Argentina

Abstract: Di Feo, L., Nome, S. F., Biderbost, E., Fuentes, S., and Salazar, L. F. 2000. Etiology of sweet potato chlorotic dwarf disease in Argentina. Plant Dis. 84:35-39. Chlorotic dwarf (CD), the most important disease in the sweet potato-producing regions of Argentina, is caused by the synergistic combination of two aphid-transmitted potyviruses with a whitefly-transmitted crinivirus. Sweet potato feathery mottle virus, sweet potato mild speckling virus, and a crinivirus (serologically related to sweet potato chlorotic stunt virus) were associated with CD. The synergistic combination of these three viruses reproduced the disease. Additional keywords: Bemisia tabaci, Myzus persicae, sweet potato sunken vein virus, synergistic virus interactions

Assessing changes in the genetic diversity of potato gene banks. 1. Effects of seed increase

Abstract: Effects of gene bank seed-increases on the genetic integrity of potato germ plasm is a major concern of gene bank managers. Thus the Association of Potato Inter-gene-bank Collaborators (APIC), a consortium of world potato gene bank leaders, initiated this joint research project using RAPD markers to determine genetic relationships between increased generations within accessions. Solanum jamesii (2n=2x=24) and S. fendleri (2n=4x=48), two wild potato species native to North America, were used as plant material. These species represented two major breeding systems found among Solanum species: outcrossing diploids and inbreeding disomic tetraploids, respectively. Comparisons were made between populations one generation apart and between sister populations generated from a common source. Fourteen such comparisons within S. jamesii accessions had an average similarity of 96.3%, and 21 such comparisons within S. fendleri accessions had an average similarity of 96.0%. No pairs of populations were significantly different, despite the fact that RAPD markers easily separated all of these very similar accessions within their respective species. Only one of six S. jamesii accessions analyzed showed a significant change in gene frequencies among generations. These findings indicate that there has been minimal loss or change of genetic diversity in ex situ germplasm using the gene bank techniques standard at NRSP-6 and other world potato gene banks.

A review of varietal change in roots, tubers and bananas: consumer preferences and other drivers of adoption and implications for breeding.

Abstract: This review of the literature on varietal change in sub-Saharan Africa looks in detail at adoption of new varieties of bananas in Uganda, cassava in Nigeria, potato in Kenya, sweetpotato in Uganda and yams in Cote d'Ivoire. The review explored three hypotheses about drivers of varietal change. There was a strong confirmation for the hypothesis that insufficient priority given to consumer-preferred traits by breeding programmes contributes to the limited uptake of modern varieties (MVs) and low varietal turnover. Lack of evidence meant the second hypothesis of insufficient attention to understanding and responding to gender differences in consumer preferences for quality and post-harvest traits was unresolved. The evidence on the third hypothesis about the informal seed system contributing to slow uptake of MVs was mixed. In some cases, the informal system has contributed to rapid uptake of MVs, but often it appears to be a barrier with inconsistent varietal naming a major challenge.