Showing papers by "International Potato Center published in 1983"
TL;DR: Potato production is increasing rapidly in the tropics and sub-tropics and is declining gradually in the temperate zone and is not expected that in the near future potato production for ethanol production will become important or that the production for starch or stock feed will increase.
Abstract: Potato production is increasing rapidly in the tropics and sub-tropics and is declining gradually in the temperate zone. It is not expected that in the near future potato production for ethanol production will become important or that the production for starch or stock feed will increase. Consumption per capita is more or less stable in Western Europe and North America but is increasing in Africa and Asia. On average, energy and protein from potatoes cost the developing-country consumer at least three times as much as from wheat or rice. Better application by farmers of existing and newly developed technologies — including better adapted cultivars, healthy seed tubers, botanical seed and low-cost storage and processing — can reduce costs per unit of output substantially, mainly by increasing yield. Doubling the yield without considerable increases in production costs per hectare would allow the potato to become a cheap vegetable in many tropical or sub-tropical areas and to become a staple food in others with favourable growing conditions.
59 citations
TL;DR: It is suggested that the warm-adapted clones of the commonly cultivated potato were selections showing an increased generalized capacity to withstand environmental stresses of several kinds rather than a specific genotypic adaptation to tolerate warm temperatures.
Abstract: Heat and cold tolerances were determined for 13 clones of the commonly cultivated potato, Solanum tuberosum L. Five clones were considered to be adapted to warm climates and the others to cool climates only in terms of their ability to produce tubers. The decrease in the rate of the induced rise in chlorophyll fluorescence after heating leaves at 41°C for 10 min was used to measure relative heat tolerance, and the decrease following chilling at 0°C was used to measure relative cold tolerance. The warm-adapted clones all showed enhanced heat tolerance compared with the cool-adapted clones. Higher heat tolerance was also correlated with a greater tolerance towards a cold stress of 0°C and it is suggested that the warm-adapted clones were selections showing an increased generalized capacity to withstand environmental stresses of several kinds rather than a specific genotypic adaptation to tolerate warm temperatures. Heat and cold tolerances were also determined for several other species of potato cultivated in the Andean region of South America. Of these, S. phureja, which is found at low altitudes on the eastern slopes of the Andes, showed a tolerance to heat comparable to that of the warm-adapted clones of the common potato, the two most heat tolerant of which contained some phureja in their parentage. Diploid and triploid species of cultivated potatoes were considerably more cold tolerant than the clones of the common potato, a tetraploid. The genetic variability for heat and cold tolerance in cultivated and wild potatoes is discussed in relation to increasing the tolerance of the potato to these stresses.
40 citations
35 citations
TL;DR: The ability of wild potatoes (Solanum spp.) to adapt to potentially stressful environmental temperatures was investigated by measuring the cold and heat tolerances of plants grown near sea-level in Lima following collection of tubers from plants growing naturally at altitudes ranging from 450 to 4,200 m.
Abstract: The ability of wild potatoes (Solanum spp.) to adapt to potentially stressful environmental temperatures was investigated by measuring the cold and heat tolerances of plants grown near sea-level in Lima following collection of tubers from plants growing naturally at altitudes ranging from 450 to 4,200 m. Relative cold tolerance was measured in leaves stored at 0°C by the decrease in the induced rise of chlorophyll fluorescence. Similarly, changes in chlorophyll fluorescence were used to determine the relative heat tolerance of leaves heated at 41°C for 10 min. With increasing altitude, the cold tolerance of different species tended to increase and conversely, heat tolerance decreased. However, these two genotypic adaptations were not closely correlated and appear to vary independently of each other in response to climate.
34 citations
TL;DR: The results indicated that yield could be increased through selection utilizing additive variance for the component traits, especially tuber size, and that rendimiento podía ser incrementado mediante selección al utilizar variancia aditiva for the atributos, especialmente for the tamano del tuérculo.
Abstract: Genetic variances were estimated for a population ofSolarium tuberosum L. subsp.andigena, selected for adaptation to north temperate climatic conditions. Estimates for 15 traits, including some unique to true seed (TPS) propagation, were obtained from trials conducted under short day conditions in Peru. Only non-additive variance was found for yield, but heritability estimates were relatively high for tuber number and tuber size. The results indicated that yield could be increased through selection utilizing additive variance for the component traits, especially tuber size. Estimates of genetic variability for tuber uniformity were low. TPS yield was positively correlated with most other traits except tuber number.
28 citations
TL;DR: In this article, a series of 14 on-farm trials indicated that improved seed-storage facilities, in the form of additional diffuse light and ventilation, may considerably reduce losses of seed-tubers and result in a better quality product: less weight loss in store, more sprouts per tuber and shorter, more robust, sprouts.
Abstract: A series of 14 on-farm trials indicated that improved seed-storage facilities, in the form of additional diffuse light and ventilation, may considerably reduce losses of seed-tubers and result in a better quality product: less weight loss in store, more sprouts per tuber and shorter, more robust, sprouts. This improvement resulted generally in improved emergence, stem number per hill, yield of marketable tubers and economic return. The improved onfarm stores compared favourably with the refrigerated storage available locally.
13 citations
TL;DR: In this article, the authors suggest that developing countries, in an effort to reduce post-harvest potato losses and to make potatoes available to an increasing number of their peoples by the year 2000, should investigate alternative low-cost application of basic principles.
11 citations
TL;DR: Foliar application of carbaryl alone, or in combination with soil-incorporated insecticides, was equally effective in reducing damage and yield loss, and foliar application of methomyl, reduced pest damage and increased yields significantly.
10 citations
TL;DR: In this article, the adoption of a new technology, namely the storage of potato seed tubers in diffuse light, is described under conditions typical of many developing countries: lack of financial and technical resources etc.
Abstract: An example of the adoption of a new technology, namely the storage of potato seed tubers in diffuse light, is described under conditions typical of many developing countries: lack of financial and technical resources etc. Progressive stages are shown within one farm. In addition, farmer awareness of seed-tuber quality and confidence in new technologies were increased so that other related technologies have been adopted prior to any apparent data on subsequent yields and economic returns, which have since been shown to be not inconsiderable.
9 citations
TL;DR: In this paper, the authors present a case in which conventional wisdom proved to be highly erroneous, as a result, use of the technology which researchers and extensionists recommended most highly (improved seed) reduced farmers' net returns.
8 citations
TL;DR: The hypothesis that S. X ajanhuiri is of hybridogenic origin and was derived from natural crosses between the cultivated and the wild potato species is supported.
Abstract: The leaf phenolics of the potato speciesS. × ajanhuiri, S. stenotomum, S. megistacrolobum and the artificial F1S. stenotomum × S. megistacrolobum hybrids have been compared using thin layer chromatography
TL;DR: Viral transmission was occurring during the storage period of potato tubers in diffuse light and dark rustic storage houses in Peru and there were significantly more plants infected with virus from tuber that had not been sprayed for aphid control than from tubers that had been sprayed.
Abstract: Population levels ofMyzus persicae (Sulzer) were studied on potato tubers in diffuse light and dark rustic storage houses in Peru. No differences in numbers of aphids/sprouted eye on potatoes infested naturally during storage in diffuse light or darkness were observed. Significantly more alate aphids were observed on tubers stored in darkness than in diffuse light storage houses. Viral transmission was occurring during the storage period. The incidence of viral transmission was not significantly influenced by storing tubers in diffuse light or dark storages. There were significantly more plants infected with virus from tubers that had not been sprayed for aphid control than from tubers that had been sprayed
TL;DR: In this paper, the introduction of a new technology to farmers in developing countries frequently necessitates complementary changes in related traditional practices, and this has been particularly true where post-ha...
Abstract: The introduction of a new technology to farmers in developing countries frequently necessitates complementary changes in related traditional practices. This has been particularly true where post-ha...
TL;DR: The efficacy of methamidophos, Salithion, phenthoate, and R&H 0994 for control of Myzus persicae (Sulzer) on stored tubers was determined and populations developed very rapidly on unsprayed tubers in rustic store.
Abstract: The efficacy of methamidophos, Salithion, phenthoate, and R&H 0994 for control ofMyzus persicae (Sulzer) on stored tubers was determined. In Huancayo, Peru, which is in the Sierra, R&H 0994 proved to be most efficacious and protected tubers for 45 days. Phenthoate, at the rate tested, was not effective. In San Ramon, Peru, which is tropical in climate, methamidophos was most efficacious and protected tubers for 22 days. In both locationsM. persicae populations developed very rapidly on unsprayed tubers in rustic store.
TL;DR: In some remote and unexplored regions of Bolivia, it is still possible to find new material, as demonstrated by the new species described herein, which represents the southern most species from South America described to date for the series Conicibaccata.
Abstract: It is probable that the wild potatoes from Bolivia are the least known of all the Andean region. Although approximately 50 species have been described from this country since Dunal, 1852, a great majority of these are synonyms. Nevertheless, in some remote and unexplored regions of Bolivia, it is still possible to find new material, as demonstrated by the new species described herein.
TL;DR: Exploratory work shows that finding new species is still possible in the isolated and remote localities of this country as demonstrated by the present new species,Solarium neovavilovii (Sect. Petota), dedicated to the great Russian scientist Nicolai I. VavILov.
Abstract: Regions such as Mexico, where important sources of resistance to late blight of potato have been found, have also been widely explored for wild potatoes. In contrast, Bolivia has received little attention. Although more than 50 names have been published for wild species from Bolivia, a great majority of these only constitute synonyms. Nevertheless, our exploratory work shows that finding new species is still possible in the isolated and remote localities of this country as demonstrated by the present new species,Solarium neovavilovii (Sect. Petota), dedicated to the great Russian scientist Nicolai I. Vavilov.
01 Jan 1983
TL;DR: There is a great deal of general research information published on growing potatoes and an average of 1,820 papers and reports annually during the past five years according to Potato Abstracts.
Abstract: There is a great deal of general research information published on growing potatoes — an average of 1,820 papers and reports annually during the past five years according to Potato Abstracts Although much of this information is concerned with diseases and pests, emphasis is skewed toward temperate zone diseases and pests. For example, less than two percent of the reports dealt with the potato tuber moth, root-knot nematodes and Pseudomonas wilt, which combined, are major production constraints of potatoes grown in a band encircling the world 30°N and 30°S of the equator.