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Sergei A Subbotin - One of the best experts on this subject based on the ideXlab platform.
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Ditylenchus gallaeformans sp. n. (Tylenchida: Anguinidae) – a neotropical nematode with biocontrol potential against weedy Melastomataceae
Nematology, 2020Co-Authors: Rosângela D L Oliveira, Sergei A Subbotin, ângelo M Santin, Dalila J Seni, Anna L Dietrich, Luis A Salazar, Renato Goldenberg, Manuel Mundo-ocampo, Robert W BarretoAbstract:Ditylenchus gallaeformans sp. n. was found on several hosts at numerous locations in Brazil and Costa Rica. In its native habitats it attacks several genera in the Melastomataceae, including two species ranked as among the worst invasive weeds of Pacific island forests, namely Miconia calvescens and Clidemia hirta. The new species causes a severe disease on infected plants involving the formation of gall-like structures on infected leaves, inflorescences and stems, and may cause significant impact on its hosts. Morphological study using light and scanning electron microscopy and analysis of the partial 18S rRNA, the D2-D3 expansion fragments of 28S rRNA and the ITS rRNA gene sequences showed little variations between populations from different hosts or geographical origins. The molecular study revealed that the new species is related to D. drepanocercus, which was recently found in association with M. calvescens but causing angular leaf spots on this host. Ditylenchus gallaeformans sp. n. is distinguished from D. drepanocercus by having a bursa reaching the tail tip (vs covering around 50% of tail in D. drepanocercus) and a conical tail, regularly tapering towards a variable tip (vs tail with a distinctive apical falciform appendage in both sexes in D. drepanocercus). PCR with species-specific primers was developed for diagnostics of both Ditylenchus species. Ditylenchus gallaeformans sp. n. deserves further investigation as a potential biocontrol agent against M. calvescens and C. hirta.
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Ditylenchus laurae sp n tylenchida anguinidae from poland a new species of the d dipsaci complex associated with a water plant potamogeton perfoliatus l
Nematology, 2017Co-Authors: Andrzej Skwiercz, Sergei A Subbotin, Aleksandra Obrepalskasteplowska, Franciszek Wojciech Kornobis, Grazyna Winiszewska, Arnika Przybylska, Magdalena GawlakAbstract:The genus Ditylenchus consists of more than 60 species, some of which are plant parasites. In this paper we report on Ditylenchus laurae sp. n. from Poland, a new species associated with the aquatic plant, Potamogeton perfoliatus L. Ditylenchus laurae sp. n. is characterised by a long and slender body with L = 1881 (1523-2095) μ m and 1875 (1690-2089) μ m, a = 88.8 (72.5-102.5) and 89.7 (71.9-97.9), stylet length = 10.8 (9.6-12.1) μ m and 8.3 (7.7-9.0) μ m, tail length = 117.2 (103.5-126.7) μ m and 102.4 (98.3-113.6) μ m in females and males, respectively; four incisures, rounded stylet knobs, long basal bulb (about ten times as long as wide), post-vulval uterine sac from 4.3-5.6 vulval body diam. long, and mucronate tail. Characterisation using the ITS rRNA, COI and hsp 90 gene sequences was conducted and a phylogenetic analyses revealed that D. laurae sp. n. belongs to the D. dipsaci complex.
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diagnostics of stem and bulb nematodes Ditylenchus weischeri and d dipsaci nematoda anguinidae using pcr with species specific primers
Canadian Journal of Plant Pathology-revue Canadienne De Phytopathologie, 2015Co-Authors: Mehrdad Madani, Mario Tenuta, Vladimir N Chizhov, Sergei A SubbotinAbstract:AbstractThe stem and bulb nematodes of the Ditylenchus dipsaci (Kuhn) Filipjev species complex are obligate endoparasites of various agricultural plants, causing stunting and swelling and resulting in significant economic losses. Recently, a new closely related Ditylenchus species, D. weischeri Chizhov, Borisov and Subbotin, a parasite of the cosmopolitan herbaceous perennial weed, Cirsium arvense (L.) Scop., was described. Many countries impose quarantine restrictions for the presence of D. dipsaci in imported plant and soil materials. In the current study, we developed PCR with species-specific primers for the rapid and reliable separation of D. weischeri and D. dipsaci using gel electrophoresis and melting curve analysis. Species-specific primer sets were designed based on the nucleotide sequence of the heat shock protein (hsp90) gene for both nematode species. The PCR protocol was verified using samples of D. weischeri, D. dipsaci and the closely related species, D. gigas, which parasitizes broadbean ...
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occurrence of Ditylenchus weischeri and not d dipsaci in field pea harvest samples and cirsium arvense in the canadian prairies
Journal of Nematology, 2014Co-Authors: Mario Tenuta, Mehrdad Madani, Shabeg S Briar, Oscar I Molina, Robert H. Gulden, Sergei A SubbotinAbstract:The stem nematode, a parasite of the herbaceous perennial weed, Cirsium arvense (L.) Scop. and identified as Ditylenchus dipsaci (Ku¨hn) Filipjev, was reported in the Canadian prairies in 1979. Recently, D. weischeri Chizhov parasitizing Cirsium arvense was described in Russia, and it has been shown that this species is not an agricultural pest. In this study, we examined Ditylenchus species found in field pea (Pisum sativum L.) grain harvest samples in 2009 and 2010 and from C. arvense shoots in pea fields in the Saskatchewan, Alberta, and Manitoba provinces. Samples from 538 fields (mainly yellow pea) were provided by 151 growers throughout the main pea-growing area of the Canadian prairies. Of the samples collected, 2% were positive for Ditylenchus. The population density of the nematode ranged between 4 and 1,500 nematodes kg-1 pea harvest sample and related to presence of C. arvense seeds. Positive samples occurred in 2009 but not in 2010 and were from throughout the pea-growing area of the Canadian prairies and not related to cropping history. C. arvense collected from yellow pea fields in Saskatchewan and Manitoba, but not Alberta, were infested with Ditylenchus. Morphological and molecular (ITS-PCR-RFLP) traits indicated that this species belongs to D. weischeri. The results indicated the stem nematode found in yellow pea grain is D. weischeri which resided with C. arvense seeds and debris to pea samples. Unlike D. dipsaci, D. weischeri is not a nematode pest of economic importance; therefore, its presence in the pea harvest samples was not a concern.
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Ditylenchus gallaeformans sp n tylenchida anguinidae a neotropical nematode with biocontrol potential against weedy melastomataceae
Nematology, 2013Co-Authors: Rosângela D L Oliveira, Sergei A Subbotin, ângelo M Santin, Dalila J Seni, Anna L Dietrich, Luis A Salazar, Manuel Mundoocampo, Renato Goldenberg, Robert W BarretoAbstract:Ditylenchus gallaeformans sp. n. was found on several hosts at numerous locations in Brazil and Costa Rica. In its native habitats it attacks several genera in the Melastomataceae, including two species ranked as among the worst invasive weeds of Pacific island forests, namely Miconia calvescens and Clidemia hirta. The new species causes a severe disease on infected plants involving the formation of gall-like structures on infected leaves, inflorescences and stems, and may cause significant impact on its hosts. Morphological study using light and scanning electron microscopy and analysis of the partial 18S rRNA, the D2-D3 expansion fragments of 28S rRNA and the ITS rRNA gene sequences showed little variations between populations from different hosts or geographical origins. The molecular study revealed that the new species is related to D. drepanocercus, which was recently found in association with M. calvescens but causing angular leaf spots on this host. Ditylenchus gallaeformans sp. n. is distinguished from D. drepanocercus by having a bursa reaching the tail tip (vs covering around 50% of tail in D. drepanocercus) and a conical tail, regularly tapering towards a variable tip (vs tail with a distinctive apical falciform appendage in both sexes in D. drepanocercus). PCR with species-specific primers was developed for diagnostics of both Ditylenchus species. Ditylenchus gallaeformans sp. n. deserves further investigation as a potential biocontrol agent against M. calvescens and C. hirta.
Mehrdad Madani - One of the best experts on this subject based on the ideXlab platform.
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molecular characterization and phylogeny of Ditylenchus weischeri from cirsium arvense in the prairie provinces of canada
Journal of Nematology, 2018Co-Authors: Mehrdad Madani, Mario TenutaAbstract:: Ditylenchus weischeri that parasitizes the weed Cirsium arvense (L.) Scop., 1772, (creeping thistle) was described in 2011 from Russia based on their morphology, ITS-RFLP analysis, and Hsp 90 gene sequence of a few individuals and one field collection of the plant. More recently, we found C. arvense parasitized by D. weischeri in the Prairie Provinces of Canada. Plant host preference for D. weischeri was also distinct from D. dipsaci (Kuhn) Filipjev, 1936. In the current study, a comprehensive molecular analysis of many D. weischeri specimens from Canada is presented. Individuals from 41 C. arvense or yellow pea grain samples with seeds of C. arvense from the Prairie Provinces were sequenced for the internal transcribed spacer (ITS rDNA), large subunit (LSU) D2D3 28S rDNA, partial segment of small subunit (SSU) 18S rDNA, and the heat shock protein Hsp 90 gene. The analysis also included D. weischeri individuals from C. arvense from Russia and garlic with D. dipsaci from the Provinces of Ontario and Quebec in Canada. Available sequence data of Ditylenchus species retrieved from GenBank were used to phylogenetically position this species within the genus Ditylenchus . In all studied genes, several single-nucleotide polymorphisms between the Canadian D. weischeri and both Russian haplotype and individuals of D. weischeri from C. arvense from Russia were found. The sequences of ITS rDNA, LSU D2D3 28S rDNA, and Hsp 90 were used to construct separate dendrograms. For each of the three genes examined, D. weischeri was grouped separately from the other Ditylenchus . Ditylenchus samples from C. arvense was positioned to a single clade such as D. weischeri and distinct from D. dipsaci . With past reports of plant host preference and morphology, the results of this study provide further evidence for the fact that D. weischeri is distinct to be separated from D. dipsaci . Furthermore, minor differences in molecular divergence and morphology to the Russian haplotype and limited symptoms of disease on C. arvense in Prairie Canada suggest the Canadian and Russian populations of D. weischeri may be diverging.
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diagnostics of stem and bulb nematodes Ditylenchus weischeri and d dipsaci nematoda anguinidae using pcr with species specific primers
Canadian Journal of Plant Pathology-revue Canadienne De Phytopathologie, 2015Co-Authors: Mehrdad Madani, Mario Tenuta, Vladimir N Chizhov, Sergei A SubbotinAbstract:AbstractThe stem and bulb nematodes of the Ditylenchus dipsaci (Kuhn) Filipjev species complex are obligate endoparasites of various agricultural plants, causing stunting and swelling and resulting in significant economic losses. Recently, a new closely related Ditylenchus species, D. weischeri Chizhov, Borisov and Subbotin, a parasite of the cosmopolitan herbaceous perennial weed, Cirsium arvense (L.) Scop., was described. Many countries impose quarantine restrictions for the presence of D. dipsaci in imported plant and soil materials. In the current study, we developed PCR with species-specific primers for the rapid and reliable separation of D. weischeri and D. dipsaci using gel electrophoresis and melting curve analysis. Species-specific primer sets were designed based on the nucleotide sequence of the heat shock protein (hsp90) gene for both nematode species. The PCR protocol was verified using samples of D. weischeri, D. dipsaci and the closely related species, D. gigas, which parasitizes broadbean ...
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occurrence of Ditylenchus weischeri and not d dipsaci in field pea harvest samples and cirsium arvense in the canadian prairies
Journal of Nematology, 2014Co-Authors: Mario Tenuta, Mehrdad Madani, Shabeg S Briar, Oscar I Molina, Robert H. Gulden, Sergei A SubbotinAbstract:The stem nematode, a parasite of the herbaceous perennial weed, Cirsium arvense (L.) Scop. and identified as Ditylenchus dipsaci (Ku¨hn) Filipjev, was reported in the Canadian prairies in 1979. Recently, D. weischeri Chizhov parasitizing Cirsium arvense was described in Russia, and it has been shown that this species is not an agricultural pest. In this study, we examined Ditylenchus species found in field pea (Pisum sativum L.) grain harvest samples in 2009 and 2010 and from C. arvense shoots in pea fields in the Saskatchewan, Alberta, and Manitoba provinces. Samples from 538 fields (mainly yellow pea) were provided by 151 growers throughout the main pea-growing area of the Canadian prairies. Of the samples collected, 2% were positive for Ditylenchus. The population density of the nematode ranged between 4 and 1,500 nematodes kg-1 pea harvest sample and related to presence of C. arvense seeds. Positive samples occurred in 2009 but not in 2010 and were from throughout the pea-growing area of the Canadian prairies and not related to cropping history. C. arvense collected from yellow pea fields in Saskatchewan and Manitoba, but not Alberta, were infested with Ditylenchus. Morphological and molecular (ITS-PCR-RFLP) traits indicated that this species belongs to D. weischeri. The results indicated the stem nematode found in yellow pea grain is D. weischeri which resided with C. arvense seeds and debris to pea samples. Unlike D. dipsaci, D. weischeri is not a nematode pest of economic importance; therefore, its presence in the pea harvest samples was not a concern.
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molecular diagnostics taxonomy and phylogeny of the stem nematode Ditylenchus dipsaci species complex based on the sequences of the internal transcribed spacer rdna
Phytopathology, 2005Co-Authors: Sergei A Subbotin, Mehrdad Madani, Dieter Sturhan, Eino L Krall, Maurice MoensAbstract:Subbotin, S. A., Madani, M., Krall, E., Sturhan, D., and Moens, M. 2005. Molecular diagnostics, taxonomy, and phylogeny of the stem nematode Ditylenchus dipsaci species complex based on the sequences of the internal transcribed spacer-rDNA. Phytopathology 95:1308-1315. The stem nematode Ditylenchus dipsaci is of great economic importance worldwide as a parasite of agricultural crops and horticultural plants. The internal transcribed spacer (ITS) of rDNA from 23 populations of the D. dipsaci complex from various host plants were amplified and sequenced. Seven previously studied populations were also included in the study. The phylogenetic analysis of the full ITS and ITS2 sequence alignments using minimum evolution, maximum parsimony, and Bayesian inference under the complex model of DNA evolution revealed trees with two main clades: (i) D. dipsaci sensu stricto with diploid chromosome numbers and comprising most isolates from agricultural, ornamental, and several wild plants, and (ii) Ditylenchus spp. with polyploid chromosome numbers, reproductively isolated from diploid populations, and subdivided into six subclades (“giant race” from Vicia faba, Ditylenchus species parasitizing various Asteraceae, and a Ditylenchus sp. from Plantago maritima). Using the energy minimization approach and comparative sequence analysis, it has been found that the secondary structure of ditylenchid ITS2 is organized in three main domains. The importance of knowledge on the RNA structure for phylogenetic analysis is discussed. Conventional polymerase chain reaction (PCR) and real-time PCR with SYBR green dye I with a species specific primer have been developed for detection and quantification of D. dipsaci sensu stricto. Validation tests revealed a rather high correlation between real numbers of fourth-stage juveniles of the stem nematodes in a sample and expected numbers detected by real-time PCR. Problems of accuracy of quantification are discussed.
Peter Mwaura - One of the best experts on this subject based on the ideXlab platform.
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application of an entomopathogenic fungus beauveria bassiana increases potato nematodes reproduction and potato tubers damage caused by Ditylenchus destructor and d dipsaci
Biological Control, 2017Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Abstract Two greenhouse experiments were conducted to investigate the influence of Beauveria bassiana inoculated in the soil together with potato tuber rot nematode ( Ditylenchus destructor ) and stem and bulb nematode ( Ditylenchus dipsaci ). Data on nematode reproduction and consequently damage caused on potato tubers by these nematodes was investigated. In both experiments, the growing medium was inoculated with B. bassiana singly or in combination with D. destructor or D. dipsaci . B. bassiana alone did not negatively influence potato growth or tuber development. However, when B. bassiana was inoculated together with nematodes, higher nematode reproduction and tuber damage was observed at the end of the experiments. Tuber numbers and above ground fresh weight were not influenced by nematodes or a combination of B. bassiana and nematodes. Tuber weight was significantly reduced when nematodes were present together with B. bassiana . Although B. bassiana is an effective bio-control agent against some Meloidogyne spp ., the application B. bassiana strain Naturalis in the presence of D. destructor and D. dipsaci might result in a detrimental interaction leading to higher nematode population densities and higher potato tuber damage.
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resistance and tolerance of potato varieties to potato rot nematode Ditylenchus destructor and stem nematode Ditylenchus dipsaci
Annals of Applied Biology, 2015Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Ditylenchus destructor and Ditylenchus dipsaci are economically important plant-parasitic nematodes, affecting potato production mostly in temperate climates. Management through crop rotation is not feasible because of their wide host range. These nematodes are listed as quarantine pests in many countries. Limited information exists on the resistance and tolerance of currently cultivated potatoes to D. destructor and D. dipsaci. Two greenhouse experiments were conducted to screen 25 potato varieties for resistance to and tolerance for D. destructor and D. dipsaci infections. Reproduction factor (RF) and relative susceptibility (RS) were used to evaluate resistance, while potato tuber damage and tuber weight reduction was used to evaluate tolerance. Based on the RF, 16 varieties were evaluated as susceptible (S) while 5 varieties were evaluated as resistant (R) to D. destructor; varieties ‘Innovator’, ‘Aveka’ and ‘Spunta’ were resistant to D. dipsaci based on RF. ‘Desiree’ was observed to be highly susceptible to D. destructor and D. dipsaci in both experiments and was used as the standard susceptible control variety for the calculation of RS. A scale of 1–9 was used to classify RS of the potato varieties to D. destructor and D. dipsaci, where 9 indicated the highest level of resistance. All classes of resistance to D. destructor and D. dipsaci were observed in the potato varieties tested in the experiments. Six varieties had significantly lower RS to D. dipsaci than the standard susceptible control variety. Tolerant to highly sensitive potato varieties to both nematodes were also observed. RS and external potato tuber damage were identified as suitable methods for resistance and tolerance determination, respectively. This study provides essential information on the status of resistance and tolerance in potato varieties against D. destructor and D. dipsaci but needs to be confirmed under field conditions.
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effect of initial population densities of Ditylenchus destructor and d dipsaci on potato tuber damage and nematode reproduction
Nematology, 2015Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Glasshouse experiments were conducted to evaluate the effect of initial population densities (Pi) of Ditylenchus destructor and D. dipsaci on potato tuber damage and nematode reproduction. Ditylenchus destructor did not influence tuber numbers but influenced tuber weight at high Pi levels. Ditylenchus dipsaci influenced tuber numbers and weights at a Pi level of 14.29 (g growing medium)−1. Tolerance limit estimates according to the Seinhorst model were very low indicating both nematode species have a major impact on potato tuber weight. External and internal tuber rot caused by both species increased with Pi levels. Ditylenchus destructor caused more tuber rot than D. dipsaci at all Pi levels. Reproduction rates of D. destructor were higher at all Pi levels studied compared to D. dipsaci. The equilibrium density of 1.3 and 0.6 for D. destructor and D. dipsaci, respectively, was observed at Pi level of 14.29 (g growing medium)−1.
M J Celetti - One of the best experts on this subject based on the ideXlab platform.
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intra racial genetic variation of Ditylenchus dipsaci isolated from garlic in ontario as revealed by random amplified polymorphic dna analysis
Canadian Journal of Plant Pathology-revue Canadienne De Phytopathologie, 2013Co-Authors: Y Qiao, B Hughes, M J Celetti, M Zaidi, A Badiss, Qing YuAbstract:Abstract The stem and bulb nematode (Ditylenchus dipsaci) was found in garlic from across Ontario in a survey conducted in 2011. Nematodes from the survey were extracted from garlic samples and the identification of Ditylenchus species was established using morphological and molecular methods. The genetic variation of 90 populations collected from different regions in the province was studied using the random amplified polymorphic DNA (RAPD) method. One population from onion and one population of D. destructor were included for comparison. Simple matching coefficiency and hierarchical cluster analysis were performed on the polymorphisms to demonstrate the intra-racial, intra-species and interspecies relationships. Genetic variation was detected in the D. dipsaci populations isolated from garlic in Ontario. All the D. dipsaci populations were separated into two distinct clusters: a small cluster consisting of 19 populations from counties in the southern part of the province, and a large cluster of 71 popul...
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discovery of potato rot nematode Ditylenchus destructor infesting garlic in ontario canada
Plant Disease, 2012Co-Authors: Qing Yu, M A Zaida, B Hughes, M J CelettiAbstract:Potato rot nematode, Ditylenchus destructor Thorne, 1945, is a serious nematode pest in a number of root and tube crops, primarily in potatoes, and is an internationally quarantined pest (2). In garlic, it was only reported in Japan (3). In 2011, a survey was conducted for the stem and bulb nematode, Ditylenchus dipsaci (Kuhn) Filipjev in Ontario, Canada. PCR analysis revealed that a population of Ditylenchus from one garlic (Allium sativum) bulb sample in a 0.81-ha field (2-acre) in the Ottawa area had a significantly longer ITS1 (approximately 100 bp) than that of D. dipsaci. Subsequent morphology and DNA sequencing concluded that the population was Ditylenchus destructor, a quarantine species in Canada. Twenty females and twenty males were fixed and permanently mounted for morphological studies. The main diagnostic characters matched the description of D. destructor by Thorne (4). The female stylets had strong knobs, 11.1 ± 0.9 (10 to 12) μm long, lateral fields with six distinct lines in the middle se...
Stefan Vidal - One of the best experts on this subject based on the ideXlab platform.
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application of an entomopathogenic fungus beauveria bassiana increases potato nematodes reproduction and potato tubers damage caused by Ditylenchus destructor and d dipsaci
Biological Control, 2017Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Abstract Two greenhouse experiments were conducted to investigate the influence of Beauveria bassiana inoculated in the soil together with potato tuber rot nematode ( Ditylenchus destructor ) and stem and bulb nematode ( Ditylenchus dipsaci ). Data on nematode reproduction and consequently damage caused on potato tubers by these nematodes was investigated. In both experiments, the growing medium was inoculated with B. bassiana singly or in combination with D. destructor or D. dipsaci . B. bassiana alone did not negatively influence potato growth or tuber development. However, when B. bassiana was inoculated together with nematodes, higher nematode reproduction and tuber damage was observed at the end of the experiments. Tuber numbers and above ground fresh weight were not influenced by nematodes or a combination of B. bassiana and nematodes. Tuber weight was significantly reduced when nematodes were present together with B. bassiana . Although B. bassiana is an effective bio-control agent against some Meloidogyne spp ., the application B. bassiana strain Naturalis in the presence of D. destructor and D. dipsaci might result in a detrimental interaction leading to higher nematode population densities and higher potato tuber damage.
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resistance and tolerance of potato varieties to potato rot nematode Ditylenchus destructor and stem nematode Ditylenchus dipsaci
Annals of Applied Biology, 2015Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Ditylenchus destructor and Ditylenchus dipsaci are economically important plant-parasitic nematodes, affecting potato production mostly in temperate climates. Management through crop rotation is not feasible because of their wide host range. These nematodes are listed as quarantine pests in many countries. Limited information exists on the resistance and tolerance of currently cultivated potatoes to D. destructor and D. dipsaci. Two greenhouse experiments were conducted to screen 25 potato varieties for resistance to and tolerance for D. destructor and D. dipsaci infections. Reproduction factor (RF) and relative susceptibility (RS) were used to evaluate resistance, while potato tuber damage and tuber weight reduction was used to evaluate tolerance. Based on the RF, 16 varieties were evaluated as susceptible (S) while 5 varieties were evaluated as resistant (R) to D. destructor; varieties ‘Innovator’, ‘Aveka’ and ‘Spunta’ were resistant to D. dipsaci based on RF. ‘Desiree’ was observed to be highly susceptible to D. destructor and D. dipsaci in both experiments and was used as the standard susceptible control variety for the calculation of RS. A scale of 1–9 was used to classify RS of the potato varieties to D. destructor and D. dipsaci, where 9 indicated the highest level of resistance. All classes of resistance to D. destructor and D. dipsaci were observed in the potato varieties tested in the experiments. Six varieties had significantly lower RS to D. dipsaci than the standard susceptible control variety. Tolerant to highly sensitive potato varieties to both nematodes were also observed. RS and external potato tuber damage were identified as suitable methods for resistance and tolerance determination, respectively. This study provides essential information on the status of resistance and tolerance in potato varieties against D. destructor and D. dipsaci but needs to be confirmed under field conditions.
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effect of initial population densities of Ditylenchus destructor and d dipsaci on potato tuber damage and nematode reproduction
Nematology, 2015Co-Authors: Peter Mwaura, Bjorn Niere, Stefan VidalAbstract:Glasshouse experiments were conducted to evaluate the effect of initial population densities (Pi) of Ditylenchus destructor and D. dipsaci on potato tuber damage and nematode reproduction. Ditylenchus destructor did not influence tuber numbers but influenced tuber weight at high Pi levels. Ditylenchus dipsaci influenced tuber numbers and weights at a Pi level of 14.29 (g growing medium)−1. Tolerance limit estimates according to the Seinhorst model were very low indicating both nematode species have a major impact on potato tuber weight. External and internal tuber rot caused by both species increased with Pi levels. Ditylenchus destructor caused more tuber rot than D. dipsaci at all Pi levels. Reproduction rates of D. destructor were higher at all Pi levels studied compared to D. dipsaci. The equilibrium density of 1.3 and 0.6 for D. destructor and D. dipsaci, respectively, was observed at Pi level of 14.29 (g growing medium)−1.