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Ward M. Tingey - One of the best experts on this subject based on the ideXlab platform.
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Performance of a North American Field Population and a Laboratory Colony of the Potato Tuberworm, Phthorimaea operculella, on Foliage of Resistant and Susceptible Potato Clones
Journal of Insect Science, 2010Co-Authors: Mahmut Dogramaci, Ward M. TingeyAbstract:Foliar resistance of two potato clones was tested against a Columbia Basin field population (CBFP) and a Colorado laboratory colony (COLC) of the potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). The first clone was a cross of a cultivated potato, Solanum tuberosum L. (Solanales: Solanaceae), and a wild potato, Solanum Berthaultii Hawkes (Q 174-2); the second clone was cv. Allegany, S. tuberosum L.. In no-choice assays, defoliation by P. operculella larvae of COLC and CBFP did not differ on Allegany and Q174-2. Larval weight and production of COLC and CBFP colonies were similarly reduced on Q174-2 compared to cv. Allegany, although larval weights and production of the CBFP population were slightly less affected by the host. Larval production by the COLC on Allegany was greater than that on Q174-2, while that of the CBFP on Allegany and Q174-2 did not differ. However, production of P. operculella larvae by the CBFP on Q174-2 during no-choice assays was greater than that in choice tests, indicating reduced host preference. Most of the larvae recovered from either host were fourth instars, followed by third instars. Although the levels of resistance expressed by Q174-2 potato clone to the two P. operculella populations differed in magnitude, nearly all of P. operculella performance criteria measured in this study were adversely affected by Q174-2 foliage compared to the commercial potato cultivar, cv. Allegany.
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Glandular Trichomes of Solanum Berthaultii and Its Hybrids with Solanum tuberosum Affect Nymphal Emergence, Development, and Survival of Empoasca fabae (Homoptera: Cicadellidae)
Journal of Economic Entomology, 2006Co-Authors: Ane Hackbart Medeiros, Ward M. TingeyAbstract:The influence of foliar glandular trichomes on developmental biology of the potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae), was examined by selective removal of trichomes on resistant and susceptible potato germplasm comprising two glandular trichome-bearing genotypes (PI 473331 and PI 473334) of wild potato, Solanum Berthaultii (Hawkes), two interspecific hybrids of S. Berthaultii with Solanum tuberosum L. (Q174-2 and NY123), and two commercial S. tuberosum cultivars ('Elba' and 'Allegany'). Adult mortality was affected, whereas nymphal emergence was unaffected by removal of glandular trichome exudates. No nymphs were observed emerging from leaves of PI 473331 or PI 473334. Regardless of the trichome removal treatment, no nymphs completed development on PI 473331, and only a small percentage of nymphs survived to adulthood on NY123 and PI 473334. PI 473331 had the greatest frequency of adults and nymphs with trichome exudate deposition on their bodies, followed by PI 473334. Nymphs, but not adults, had exudate accumulation when caged on foliage of Q174-2. Removal of type A trichome heads and type B droplets eliminated exudate deposition. The results of these studies provide evidence that phenolic oxidation chemistry and the physical barrier imposed by trichomes of S. Berthaultii are responsible for much of the observed resistance but that other factors possibly linked to the presence of trichomes aid in the expression on resistance.
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Aspects of tuber resistance in hybrid potatoes to potato tuber worm
Entomologia Experimentalis Et Applicata, 2006Co-Authors: Raksha Malakar-kuenen, Ward M. TingeyAbstract:Tubers produced from crosses between the wild potato, Solanum Berthaultii Hawkes (Solanaceae), and the cultivated species Solanum tuberosum L. (Solanaceae) are resistant to potato tuber worm (PTW), Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), infestation compared to those of the popular commercial North American cultivars Allegany, Atlantic, Chieftain, Katahdin, MaineChip, NorDonna, Norwis, Russet Norkotah, Snowden, and Yukon Gold. Given a choice between Atlantic and hybrid tubers, female PTW deposited ca. 50% fewer eggs on hybrid tubers than on those of Atlantic; larval survival and production of prepupae on hybrid tubers were reduced similarly. Time needed for neonates to penetrate eye buds was ca. 100 min greater on hybrid tubers compared to that on cv. Atlantic. Periderm of hybrid tubers is thicker than that of cv. Atlantic and may contribute to the delay in larval penetration of tubers and the success of initial establishment.
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Aspects of Potato Leafhopper (Homoptera: Cicadellidae) Biology on Solanum Berthaultii and Other Potato Genotypes
Journal of Economic Entomology, 2005Co-Authors: Ane Hackbart Medeiros, Italo Delalibera, Ward M. TingeyAbstract:Survival of nymphs and adult males and females of potato leafhopper, Empoasca fabae (Harris), on six potato (Solanum spp.) genotypes with varied levels of resistance was evaluated and related to type, density, and droplet/head size of foliar glandular trichomes. Survival was greater on Solanumtuberosum cultivars (OAlleganyO and OElbaO) compared with accessions of the wildS.Berthaultii (PI 473331 and PI 473334). The barrier provided by glandular trichomes may affect survival ofE.fabae by restricting nymph and adult feeding. PI 473331 was the most pubescent host, bearing type A and type B trichomes and the most unsuitable host for E. fabae. Allegany possesses leasets with low trichome densities and small gland diameter and was the most suitable host for adult E.fabae survival. Females generally had higher survival rates than males. Nymphal and adult leafhoppers differed greatly in their survival rates, particularly onS.tuberosumS.Berthaultii hybrids (Q174-2 and NY123). Interestingly, nymphs had longer (190 d) mean lethal time (LT50) than adults (31 d) when held on Q174-2, and a lower LT50 (19 d) when held on NY123 compared with adults (104 d). Starvation, dehydration, or both were likely associated with mortality of nymphs conÞned on PI 473331 and PI 473334. Nymphs on these accessions died at a comparable rate to those conÞned on a starvation treatment and more rapidly than those supplied with water only, sucrose solution or other potato genotypes. Darkened trichome exudates were observed on insects held on PI 473331 and PI 473334, consistent with previous reports that glandular trichomes of S. Berthaultii contain phenolic oxidation chemistry. This study aids in the identiÞcation of the probable mechanisms of resistance to E. fabae used by S. berthaulti and its hybrids with S. tuberosum.
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Phenolic oxidase activities in glandular trichomes of Solanum Berthaultii
Phytochemistry, 2001Co-Authors: James D. Ryan, Peter Gregory, Ward M. TingeyAbstract:Abstract Polyphenol oxidase and peroxidase activities were detected in foliar glandular trichomes of the wild, insect-resistant potato species, Solanum Berthaultii . These enzyme activities may provide the basis for conversion of clear, viscous trichome exudate into a hard, brown substance which is formed rapidly after insect attack.
Yvan Pelletier - One of the best experts on this subject based on the ideXlab platform.
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Trade-off between foliage and tuber resistance to Phthorimaea operculella in wild potatoes
Entomologia Experimentalis Et Applicata, 2009Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:Plants allocate resources between defence, reproduction, maintenance, and growth. This can lead to detectable allocation and ecological costs expressed as trade-offs between distinct plant functions. It could also lead to trade-offs between a plant's defences to different kinds of herbivores or a plant's defences to herbivory on different plant parts. We examined the hypothesis that allocation to defence in leaves is inversely related to allocation to defence in tubers of two distinct trichome-bearing morphotypes of the wild potato, Solanum Berthaultii Hawkes (Solanaceae). This species has been widely used in potato breeding programs aimed at acquiring foliage resistance to Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae) and other herbivores. Phthorimaea operculella lays eggs in the soil and neonate larvae generally initiate host attack. We exposed leaves and tubers from multiple wild potato populations to neonate P. operculella. For both plant morphotypes, survival of neonate larvae placed on foliage was negatively correlated with the survival of neonate larvae placed on tubers, suggesting a trade-off between the levels of herbivore defence in these plant tissues. These results suggest that the evolution of tuber resistance and trichome-mediated foliage resistance to herbivores may not be independent, and that potato-breeding programs that select for resistance in one tissue might compromise resistance in another.
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Effects of altitude of origin on trichome-mediated anti-herbivore resistance in wild Andean potatoes
Flora, 2008Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:Abstract The diversity and abundance of herbivores often decreases with increasing altitude. Plants are expected to respond to reduced herbivore pressure by allocating fewer resources to anti-herbivore resistance at higher altitudes. This study uses a greenhouse experiment and parallel bioassay to examine population variability in trichome-mediated defenses across a range of accessions of Solanum Berthaultii Hawkes and S. tarijense Hawkes that originated from different altitudes. S. Berthaultii bears two types of glandular trichomes, type A and type B, whereas S. tarijense has type A trichomes only, and hairs resembling type B trichomes that are eglandular. Both type A and type B glandular trichomes on S. Berthaultii deterred ovipositing female Phthorimaea operculella (Zell.) (Lepidoptera: Gelechiidae). The density of type A, but not type B trichomes decreased with increasing altitude of origin in S. Berthaultii populations. The ratio of type A to type B trichomes on the abaxial surface of S. Berthaultii negatively affected oviposition and was inversely related to altitude of origin. In S. tarijense, type A trichomes deterred, but eglandular leaf hairs stimulated oviposition. Consequently, the ratio of type A trichomes to eglandular leaf hairs was negatively related to the number of eggs laid. The total numbers of trichomes per leaf generally increased with increasing altitude of origin in S. tarijense whereas the ratio of type A trichomes to eglandular hairs declined. In the oviposition bioassay, we found no direct relationship between resistance and altitude of origin, which may have been due to differences in leaf area at the time of the bioassay. Nevertheless, the results suggest that populations of both plant species that originated from higher altitudes were generally more susceptible to ovipositing P. operculella.
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Periderm- and cortex-based resistance to tuber-feeding Phthorimaea operculella in two wild potato species
Entomologia Experimentalis Et Applicata, 2007Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Alberto Salas, Yvan PelletierAbstract:The trichome-bearing wild potatoes Solanum Berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae) have noted resistance to leaf-feeding insect herbivores; however, little is known about their resistance to tuber-feeding herbivores. This study evaluates resistance in tubers of these two species to attack by the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). Tu bers from a range of accessions were presented to recently emerged neonate tuber moth larvae. Resistance to neonates varied between accessions and was generally higher in accessions of S. tarijense . The contribution to observed resistance of periderm vs. cortex factors was assessed by perforating tuber periderm in paired-tuber experiments. Across species and accessions, an average of 62% of resistance was attributed to periderm-related factors. All larvae entered tubers through the eyes. Unidentified cortex-related factors affected larval development time and pupal weight. Sprouting compromised resistance by reducing the protective value of the periderm. The degree of sprouting also decreased larval development times and increased pupal weights in one of two accessions examined. These results demonstrate the potential of S. Berthaultii and S. tarijense as sources of tuber-resistance and identify accessions of both species with notably high periderm-based protection. Levels of periderm resistance were not correlated to levels of cortex resistance and represent an independent resistance source compatible with the food value of crop potato.
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Variable responses of tuber moth to the leaf trichomes of wild potatoes
Entomologia Experimentalis Et Applicata, 2007Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:This study examines the response of tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), during the initial stages of attack, to variability in trichome density and composition on foliage of Solanum Berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae). Solanum Berthaultii bears two types of glandular trichome (type A and type B) that together reduced oviposition by the moth. Females were often completely deterred from ovipositing on foliage with >300 trichomes per cm 2 . In contrast, neonate establishment on S. Berthaultii was generally positively related to trichome densities, indicating that trichomes may be a poor defense against P. operculella when the moth oviposits in soil and neonate larvae select the host plant. Solanum tarijense has only one type of glandular trichome (type A) and eglandular hairs. Most eggs were deposited on the adaxial leaf surfaces that had lower trichome densities. Although the density of type A trichomes was negatively related to oviposition, high densities of hairs on the abaxial and adaxial leaf surfaces appeared to stimulate oviposition, leading to stronger positive relations between hair densities and oviposition. Larvae generally established on the abaxial surface where hair densities were greatest. Relationships between the abaxial densities of leaf hairs and neonate establishment on S. tarijense were positive. The results indicate that the responses by P. operculella to the types and density of trichomes are complex. Whereas type A and type B trichomes may act synergistically to reduce oviposition by the moth, leaf hairs do not defend against oviposition and neither leaf hairs nor type A and B trichomes reduce neonate establishment by this herbivore species.
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Biological and genetic study on the utilization of Solanum Berthaultii Hawkes by the Colorado potato beetle (Leptinotarsa decemlineata (Say))
Canadian Journal of Zoology, 1991Co-Authors: Yvan Pelletier, Zane SmilowitzAbstract:Solanum Berthaultii Hawkes is used in some potato breeding programs because of its resistance to insects. This close relative of Solanum tuberosum L. may eventually be introduced as a hybrid with the potato, in the geographic distribution of the Colorado potato beetle. To evaluate the fate of such a resistant variety derived from S. Berthaultii, the biological performance and the genetic potential for adaptation of the Colorado potato beetle on S. Berthaultii has been evaluated. Survival, developmental time, prepupal weight, fecundity, and egg weight were the fitness parameters considered. Survival and fecundity were reduced and more variable on S. Berthaultii than on S. tuberosum, but developmental time and prepupal weight were similar on both plant species. The egg weight was not affected by the plant species or the parentage and did not influence the larval fitness parameters. For all the fitness parameters studied, except egg weight, a significant effect of the "Host × Sire" component was observed, in...
Jurgen Lorenzen - One of the best experts on this subject based on the ideXlab platform.
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A QTL that confers resistance to Colorado potato beetle (Leptinotarsa decemlineata [Say]) in tetraploid potato populations segregating for leptine
Theoretical and Applied Genetics, 2009Co-Authors: B. Sagredo, H. Casper, N. Balbyshev, Abbas Lafta, Jurgen LorenzenAbstract:Genetic resistance to Colorado potato beetle ( Leptinotarsa decemlineata [Say]) from Solanum chacoense has been incorporated in the tetraploid potato selection, ND4382-19, which is highly resistant and contains moderate level of foliar leptines. We recently reported using ND4382-19 progeny, population ND5873 (ND4382-19 × Chipeta), to map two genes that segregated as complementary epistatic genes that allow accumulation of leptinidine ( Lep ) and acetyl-leptinidine ( AL ) on chromosomes 2 and 8, respectively. We describe here the characterization of a second half-sib population NDG116 (ND4382-19 × N142-72). In this population, solasodine from parent N142-72, which has Solanum Berthaultii in its background, was predominant over solanidine-based alkaloids. Concentrations of solanidine, leptinidine, and acetyl-leptinidine were 15-, 5-, and 14-fold lower than in the ND5873 population. Nevertheless, Lep and AL mapped to the same locations on chromosomes 2 and 8 of parent ND4382-19, respectively. The two populations were evaluated for resistance to Leptinotarsa in field assays, and by detached leaf assay for population NDG116. In both families, QTL analysis identified a major QTL from ND4382-19 on the distal end of chromosome 2, close to the Lep locus. The contribution of this QTL to resistance ranged from 11 to 34% for ND5873 at four field sites. Contribution to resistance from the linkage group that contains the gene AL for the accumulation of leptine was not detected. In family NDG116, the same chromosome 2 QTL was detected for field and detached leaf assays, explaining 26 and 12% of the variance for defoliation and larval development, respectively. These data may indicate another resistance mechanism besides leptine in the Leptinotarsa resistance observed in these populations.
Finbarr G. Horgan - One of the best experts on this subject based on the ideXlab platform.
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Trade-off between foliage and tuber resistance to Phthorimaea operculella in wild potatoes
Entomologia Experimentalis Et Applicata, 2009Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:Plants allocate resources between defence, reproduction, maintenance, and growth. This can lead to detectable allocation and ecological costs expressed as trade-offs between distinct plant functions. It could also lead to trade-offs between a plant's defences to different kinds of herbivores or a plant's defences to herbivory on different plant parts. We examined the hypothesis that allocation to defence in leaves is inversely related to allocation to defence in tubers of two distinct trichome-bearing morphotypes of the wild potato, Solanum Berthaultii Hawkes (Solanaceae). This species has been widely used in potato breeding programs aimed at acquiring foliage resistance to Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae) and other herbivores. Phthorimaea operculella lays eggs in the soil and neonate larvae generally initiate host attack. We exposed leaves and tubers from multiple wild potato populations to neonate P. operculella. For both plant morphotypes, survival of neonate larvae placed on foliage was negatively correlated with the survival of neonate larvae placed on tubers, suggesting a trade-off between the levels of herbivore defence in these plant tissues. These results suggest that the evolution of tuber resistance and trichome-mediated foliage resistance to herbivores may not be independent, and that potato-breeding programs that select for resistance in one tissue might compromise resistance in another.
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Effects of altitude of origin on trichome-mediated anti-herbivore resistance in wild Andean potatoes
Flora, 2008Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:Abstract The diversity and abundance of herbivores often decreases with increasing altitude. Plants are expected to respond to reduced herbivore pressure by allocating fewer resources to anti-herbivore resistance at higher altitudes. This study uses a greenhouse experiment and parallel bioassay to examine population variability in trichome-mediated defenses across a range of accessions of Solanum Berthaultii Hawkes and S. tarijense Hawkes that originated from different altitudes. S. Berthaultii bears two types of glandular trichomes, type A and type B, whereas S. tarijense has type A trichomes only, and hairs resembling type B trichomes that are eglandular. Both type A and type B glandular trichomes on S. Berthaultii deterred ovipositing female Phthorimaea operculella (Zell.) (Lepidoptera: Gelechiidae). The density of type A, but not type B trichomes decreased with increasing altitude of origin in S. Berthaultii populations. The ratio of type A to type B trichomes on the abaxial surface of S. Berthaultii negatively affected oviposition and was inversely related to altitude of origin. In S. tarijense, type A trichomes deterred, but eglandular leaf hairs stimulated oviposition. Consequently, the ratio of type A trichomes to eglandular leaf hairs was negatively related to the number of eggs laid. The total numbers of trichomes per leaf generally increased with increasing altitude of origin in S. tarijense whereas the ratio of type A trichomes to eglandular hairs declined. In the oviposition bioassay, we found no direct relationship between resistance and altitude of origin, which may have been due to differences in leaf area at the time of the bioassay. Nevertheless, the results suggest that populations of both plant species that originated from higher altitudes were generally more susceptible to ovipositing P. operculella.
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Periderm- and cortex-based resistance to tuber-feeding Phthorimaea operculella in two wild potato species
Entomologia Experimentalis Et Applicata, 2007Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Alberto Salas, Yvan PelletierAbstract:The trichome-bearing wild potatoes Solanum Berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae) have noted resistance to leaf-feeding insect herbivores; however, little is known about their resistance to tuber-feeding herbivores. This study evaluates resistance in tubers of these two species to attack by the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). Tu bers from a range of accessions were presented to recently emerged neonate tuber moth larvae. Resistance to neonates varied between accessions and was generally higher in accessions of S. tarijense . The contribution to observed resistance of periderm vs. cortex factors was assessed by perforating tuber periderm in paired-tuber experiments. Across species and accessions, an average of 62% of resistance was attributed to periderm-related factors. All larvae entered tubers through the eyes. Unidentified cortex-related factors affected larval development time and pupal weight. Sprouting compromised resistance by reducing the protective value of the periderm. The degree of sprouting also decreased larval development times and increased pupal weights in one of two accessions examined. These results demonstrate the potential of S. Berthaultii and S. tarijense as sources of tuber-resistance and identify accessions of both species with notably high periderm-based protection. Levels of periderm resistance were not correlated to levels of cortex resistance and represent an independent resistance source compatible with the food value of crop potato.
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Variable responses of tuber moth to the leaf trichomes of wild potatoes
Entomologia Experimentalis Et Applicata, 2007Co-Authors: Finbarr G. Horgan, Dan T. Quiring, Aziz Lagnaoui, Yvan PelletierAbstract:This study examines the response of tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), during the initial stages of attack, to variability in trichome density and composition on foliage of Solanum Berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae). Solanum Berthaultii bears two types of glandular trichome (type A and type B) that together reduced oviposition by the moth. Females were often completely deterred from ovipositing on foliage with >300 trichomes per cm 2 . In contrast, neonate establishment on S. Berthaultii was generally positively related to trichome densities, indicating that trichomes may be a poor defense against P. operculella when the moth oviposits in soil and neonate larvae select the host plant. Solanum tarijense has only one type of glandular trichome (type A) and eglandular hairs. Most eggs were deposited on the adaxial leaf surfaces that had lower trichome densities. Although the density of type A trichomes was negatively related to oviposition, high densities of hairs on the abaxial and adaxial leaf surfaces appeared to stimulate oviposition, leading to stronger positive relations between hair densities and oviposition. Larvae generally established on the abaxial surface where hair densities were greatest. Relationships between the abaxial densities of leaf hairs and neonate establishment on S. tarijense were positive. The results indicate that the responses by P. operculella to the types and density of trichomes are complex. Whereas type A and type B trichomes may act synergistically to reduce oviposition by the moth, leaf hairs do not defend against oviposition and neither leaf hairs nor type A and B trichomes reduce neonate establishment by this herbivore species.
B. Sagredo - One of the best experts on this subject based on the ideXlab platform.
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A QTL that confers resistance to Colorado potato beetle (Leptinotarsa decemlineata [Say]) in tetraploid potato populations segregating for leptine
Theoretical and Applied Genetics, 2009Co-Authors: B. Sagredo, H. Casper, N. Balbyshev, Abbas Lafta, Jurgen LorenzenAbstract:Genetic resistance to Colorado potato beetle ( Leptinotarsa decemlineata [Say]) from Solanum chacoense has been incorporated in the tetraploid potato selection, ND4382-19, which is highly resistant and contains moderate level of foliar leptines. We recently reported using ND4382-19 progeny, population ND5873 (ND4382-19 × Chipeta), to map two genes that segregated as complementary epistatic genes that allow accumulation of leptinidine ( Lep ) and acetyl-leptinidine ( AL ) on chromosomes 2 and 8, respectively. We describe here the characterization of a second half-sib population NDG116 (ND4382-19 × N142-72). In this population, solasodine from parent N142-72, which has Solanum Berthaultii in its background, was predominant over solanidine-based alkaloids. Concentrations of solanidine, leptinidine, and acetyl-leptinidine were 15-, 5-, and 14-fold lower than in the ND5873 population. Nevertheless, Lep and AL mapped to the same locations on chromosomes 2 and 8 of parent ND4382-19, respectively. The two populations were evaluated for resistance to Leptinotarsa in field assays, and by detached leaf assay for population NDG116. In both families, QTL analysis identified a major QTL from ND4382-19 on the distal end of chromosome 2, close to the Lep locus. The contribution of this QTL to resistance ranged from 11 to 34% for ND5873 at four field sites. Contribution to resistance from the linkage group that contains the gene AL for the accumulation of leptine was not detected. In family NDG116, the same chromosome 2 QTL was detected for field and detached leaf assays, explaining 26 and 12% of the variance for defoliation and larval development, respectively. These data may indicate another resistance mechanism besides leptine in the Leptinotarsa resistance observed in these populations.