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.

The effect of density on tuber yield in plants grown from true potato seed in seed beds during two contrasting seasons

Abstract: The production of potatoes from true seed was studied in direct-sown seed beds during both winter and summer seasons in Lima, Peru. After emergence, seedlings were thinned to give 6, 12, 24, 48 or 96 plants per m2. In all five density treatments plants were arranged in a square configuration. In both seasons, increasing plant density significantly increased total tuber number as well as tuber weights in the grades 1–5 g, 5–20 g and 20–40 g. The yield of tubers larger than 40 g was similar in all densities. In the warm summer season, tuber number was significantly reduced and mean tuber weight was 56% greater compared with that in the winter season. The potential of producing consumer potatoes from true seed in seed beds in warm climates is discussed.

Explaining Andean Potato Weevils in Relation to Local and Landscape Features: A Facilitated Ecoinformatics Approach

Abstract: Background Pest impact on an agricultural field is jointly influenced by local and landscape features. Rarely, however, are these features studied together. The present study applies a “facilitated ecoinformatics” approach to jointly screen many local and landscape features of suspected importance to Andean potato weevils (Premnotrypes spp.), the most serious pests of potatoes in the high Andes. Methodology/Principal Findings We generated a comprehensive list of predictors of weevil damage, including both local and landscape features deemed important by farmers and researchers. To test their importance, we assembled an observational dataset measuring these features across 138 randomly-selected potato fields in Huancavelica, Peru. Data for local features were generated primarily by participating farmers who were trained to maintain records of their management operations. An information theoretic approach to modeling the data resulted in 131,071 models, the best of which explained 40.2–46.4% of the observed variance in infestations. The best model considering both local and landscape features strongly outperformed the best models considering them in isolation. Multi-model inferences confirmed many, but not all of the expected patterns, and suggested gaps in local knowledge for Andean potato weevils. The most important predictors were the field's perimeter-to-area ratio, the number of nearby potato storage units, the amount of potatoes planted in close proximity to the field, and the number of insecticide treatments made early in the season. Conclusions/Significance Results underscored the need to refine the timing of insecticide applications and to explore adjustments in potato hilling as potential control tactics for Andean weevils. We believe our study illustrates the potential of ecoinformatics research to help streamline IPM learning in agricultural learning collaboratives.

Ex Situ conservation of potato [Solanum Section Petota (Solanaceae)] genetic resources in genebanks.

Abstract: Conserving the genetic diversity of potato is critical for the long-term future of potato improvement programs. Further, it is the social and ethical responsibility of the present generation to ensure future generations have the same opportunities to use, exploit, and benefit from the genetic diversity that exists today. Genebanks and the ex situ conservation of potato genetic resources are the only way to ensure this happens; in situ conservation plays a complementary role, but it can never ensure that the vast diversity that exists on earth today is still there for use in the future. Material in ex situ genebanks not only serve as a reservoir of ready-to-use genetic material when needed but also provide invaluable tools for research now and in the future of cultivated potato and its wild relatives.

Temperature-dependent phenology and growth potential of the Andean potato tuber moth,Symmetrischema tangolias(Gyen) (Lep., Gelechiidae)

Abstract: The Andean potato tuber moth, Symmetrischema tangolias (Gyen) [Lepidoptera, Gelechiidae], is an economically important pest of potato (Solanum tuberosum L.) in the mid-elevated Andean region and an invasive pest of partially global importance. Determination of the pest's population life table parameters is essential for understanding population development and growth under a variety of climates and as part of a pest risk analysis. The development, mortality and reproduction were studied in two pest populations (from Peru and Ecuador) in which cohorts of each life stage were exposed to different constant temperatures ranging from 10°C to 28°C. Using the Insect Life Cycle Modeling software, nonlinear equations were fitted to the data and an overall phenology model established to simulate life table parameters based on temperature. The temperature-dependent development curve was statistically well described for eggs by Ratkowsky's model and for larvae and pupae by Taylor's model. Variability in development time among individuals independent of temperature was significantly described by a log-logistic model. Temperature effects on immature mortality were described using different nonlinear models. Optimal temperature for survival was between 14° and 17°C. Temperature effects on adult senescence and oviposition time were described by simple exponential models; within-group variability was described by a Weibull distribution function. Fecundity per female due to temperature followed a nonlinear model indicating maximum reproduction at ~17°C. The established model revealed good convergence with historical life tables established at fluctuating temperatures. The results confirm that S. tangolias is more adapted to cooler temperature than the common potato tuber moth, Phthorimaea operculella (Zeller). S. tangolias develops at temperatures within the range of 8–28.8°C with a maximum finite rate of population increase (=1.053) at 21°C. The established process-based physiological model can be used globally to simulate life table parameters for S. tangolias based on temperature and should prove helpful for evaluating the potential establishment risk and in adjusting pest management programmes.