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Papers by Dick Peters

Research paper thumbnail of Variation in tospovirus transmission between populations of Frankliniella occidentalis (Thysanoptera: Thripidae)

Bulletin of Entomological Research, 1999

Fourteen populations of the western flower thrips Frankliniella occidentalis Pergande, originatin... more Fourteen populations of the western flower thrips Frankliniella occidentalis Pergande, originating from different hosts and countries in Asia, Europe, North America and New Zealand, were analysed for their competency and efficiency to transmit tomato spotted wilt virus (TSWV). All populations acquired and subsequently transmitted the virus, and were thus competent to transmit. They show marked differences in their efficiency, expressed as the percentage of transmitting adults. Efficiencies varied from 18% for a F. occidentalis population from the USA (US2) to 75% for a population from Israel (IS2). The differences between populations were not affected by the amount of virus ingested or by the host plant used. However, the tospovirus species studied and age at which the larvae acquired the virus affected the efficiency to transmit. First instar larvae of the NL3 population from The Netherlands were able to acquire tomato spotted wilt virus, whereas second instar larvae failed to do s...

Research paper thumbnail of Molecular characterization of cucurbit aphid-borne yellows virus isolates associated with 'namamarako' in the Philippines and 'Mara ba' in Thailand

Research paper thumbnail of Characterization of Tomato spotted wilt virus from Paprika in Korea

The Plant Pathology Journal, 2004

Research paper thumbnail of Characterization of a Tospovirus Isolate of Iris Yellow Spot Virus Associated with a Disease in Onion Fields in Brazil

Plant Disease, 1999

A tospovirus from onion causing a disease known as “sapeca” by growers in Brazil was characterize... more A tospovirus from onion causing a disease known as “sapeca” by growers in Brazil was characterized. Symptoms on onion consisted of numerous eyelike spots on the leaves and flower stalks resulting in flower abortion. Nicotiana benthamiana and N. rustica were the only systemic hosts experimentally found. Double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) experiments demonstrated that this virus was serologically related to iris yellow spot virus (IYSV), a tospovirus recently described in the Netherlands. This virus, from onion, based on an amino acid sequence identity of 90.5% for the N gene protein, is regarded as a strain of IYSV and is designated IYSVBR This 10% divergence in the nucleocapsid protein may represent an adaptation of the virus to distinct ecological niches.

Research paper thumbnail of Genome structure and sequence analysis of the tomato spotted wilt virus genome

Research paper thumbnail of Morphogenesis of sonchus yellow net virus in cowpea protoplasts

Journal of ultrastructure …, 1985

... Nikolai AM van Beek 1 , Dick Lohuis, Jeanne Dijkstra and Dick Peters Corresponding Author Con... more ... Nikolai AM van Beek 1 , Dick Lohuis, Jeanne Dijkstra and Dick Peters Corresponding Author Contact Information. ... of major ultrastructural changes consisted of appearance in the nucleus, 10 hr after inoculation, of a granular matrix with coiled nucleocapsid strands at its edge ...

Research paper thumbnail of Symptomatology and serology of plum pox virus isolates using antibodies to the N-termini of coat protein

Research paper thumbnail of Investigation of two polyclonal antisera to plum pox virus recovered at different stages after immunization

Research paper thumbnail of Rapid Technique for Determining Greenbug (Homoptera: Aphididae) Biotypes B, C, E, and F

Journal of Economic Entomology, 1988

A method for quickly determining greenbug, Schizaphis graminum (Rondani), biotypes B, C, E, and F... more A method for quickly determining greenbug, Schizaphis graminum (Rondani), biotypes B, C, E, and F was developed. 'Largo' resistance in 'TAM 105' x 'Largo' (5 x L), 'Triumph 64' (TR), 'TAM 107' (107), and 'CI 9058' was evaluated against biotype F so these host relationships could be compared to other biotypes. Mean damage ratings for 5 x L did not differ significantly from the susceptible checks, TR and 107. Therefore, only TR, 107, and 5 x L are needed to differentiate the biotypes. These cultivars were exposed for feeding exposure times of I, 2, 4, and 6 h to determine the time required for each biotype to make lesions. Feeding damage appeared as brown lesions on the leaves of susceptible plants. Lesions did not form on cultivars resistant to each biotype. Counts of lesions per leaf were made 24, 48, 72, and 96 h after infestation. All of the lesions that were to appear did so by 72 h after infestation. Some of the susceptible plants developed lesions at the 1-and 2-h feeding exposure. All of the susceptible plants formed lesions at the 4-and 6-h feeding times. Mean lesion numbers of 5.0 and 5.2 for 4 and 6 h, respectively, were not significantly different. Our technique permits biotype determinations to be made within 2 wk after aphid collection. Details on the construction of a clip cage, which is an integral part of the methodology, are provided.

Research paper thumbnail of Determination of the Median Latent Period of Two Tospoviruses in Frankliniella occidentalis, Using a Novel Leaf Disk Assay

Research paper thumbnail of Decreased preference and reproduction, and increased mortality of Frankliniella occidentalis on thrips-resistant pepper plants

Entomologia Experimentalis et Applicata, 2004

The effect of thrips resistance in pepper (Capsicum annuum L.) previously shown to result in impe... more The effect of thrips resistance in pepper (Capsicum annuum L.) previously shown to result in impeded thrips population development (Maris PC, Joosten NN, Goldbach RW & Peters D (2003a) Restricted spread of Tomato spotted wilt virus in thrips-resistant pepper. Phytopathology 93: 12231227. Maris PC, Joosten NN, Goldbach RW & Peters D (2003b) Spread of Tomato spotted wilt virus and population

Research paper thumbnail of Serological differentiation of 20 isolates of tomato spotted wilt virus

Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing f... more Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing five different procedures using a rabbit polyclonal antiserum against nucleocapsid proteins (NuAbR) and mouse monoclonal antibodies (MAbs), two directed to nucleocapsid proteins (N1 and N2) and four directed to glycoproteins G1 to G4. All the antisera were raised against TSWV-CNPH1. The 20 isolates were differentiated into two distinct serogroups. Serogroup I consisting of 16 isolates strongly reacted with NuAbR. The other four isolates were poorly recognized by NuAbR and were placed in another serogroup, designated II. The panel of MAbs differentiated the TSWV isolates into three serotypes. The 16 isolates forming serogroup I reacted strongly with the MAbs generated and were identified as serotype I isolates. The four isolates which made up serogroup II were split into serotypes II and III. The serotype II isolates did not respond or responded poorly with MAbs N1, N2 and G3. The two other isolates placed in serotype III were recognized by N1 but not by N2 and G3. Two isolates became defective after several mechanical passages and failed to respond or responded very poorly with MAbs directed to glycoproteins. Our results show that ELISA employing polyclonal and monoclonal antisera is a useful tool to differentiate TSWV isolates and to detect defective forms. The results also strongly suggest that TSWV nucleocapsid proteins are less conserved than the glycoproteins.

Research paper thumbnail of Serological differentiation of 20 isolates of tomato spotted wilt virus

Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing f... more Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing five different procedures using a rabbit polyclonal antiserum against nucleocapsid proteins (NuAbR) and mouse monoclonal antibodies (MAbs), two directed to nucleocapsid proteins (N1 and N2) and four directed to glycoproteins G1 to G4. All the antisera were raised against TSWV-CNPH1. The 20 isolates were differentiated into two distinct serogroups. Serogroup I consisting of 16 isolates strongly reacted with NuAbR. The other four isolates were poorly recognized by NuAbR and were placed in another serogroup, designated II. The panel of MAbs differentiated the TSWV isolates into three serotypes. The 16 isolates forming serogroup I reacted strongly with the MAbs generated and were identified as serotype I isolates. The four isolates which made up serogroup II were split into serotypes II and III. The serotype II isolates did not respond or responded poorly with MAbs N1, N2 and G3. The two other isolates placed in serotype III were recognized by N1 but not by N2 and G3. Two isolates became defective after several mechanical passages and failed to respond or responded very poorly with MAbs directed to glycoproteins. Our results show that ELISA employing polyclonal and monoclonal antisera is a useful tool to differentiate TSWV isolates and to detect defective forms. The results also strongly suggest that TSWV nucleocapsid proteins are less conserved than the glycoproteins.

Research paper thumbnail of Hypocomplementæmic Membranoproliferative Glomerulonephritis and Nephrotic Syndrome Associated with Partial Lipodystrophy of the Face and Trunk

Proceedings of the Royal Society of Medicine

Research paper thumbnail of Spread of Tomato spotted wilt virus and population development of Frankliniella occidentalis in pepper resistant to thrips

The effect of thrips resistance on both the spread of Tomato spotted wilt virus (TSWV) and the po... more The effect of thrips resistance on both the spread of Tomato spotted wilt virus (TSWV) and the population development of its major vector Frankliniella occidentalis was analysed on resistant and susceptible pepper (Capsicum) accessions. After release of viruliferous thrips, spread of TSWV was significantly lower in the primary and delayed in the secondary infection phase in plots with the thrips-resistant accession CPRO-1 compared to plots with the thrips susceptible accession Pikante Reuzen. Similar results were obtained in plots with a 1:1 mixture of plants of both accessions. Spread to the virus-resistant accessions PI 152225 and PI 159236, resistant and susceptible to thrips, respectively, was delayed in the secondary phase to plants of the former accession. Since the delay of the infection in the plots with thrips-resistant plants could only partly be explained by an impeded development of thrips populations, other factors, probably related to the behaviour of thrips, also affect the transmission of TSWV to the resistant plants. The results obtained indicate that thrips resistance in pepper can be a useful tool in IPM strategies to control TSWV infections.

Research paper thumbnail of Molecular Diagnosis of Iris Yellow Spot Virus (IYSV) on Onion in Iran

Journal of Agricultural Science and Technology, 2012

Viral symptoms indicative of Iris yellow spot virus (IYSV) were observed on onion in several fiel... more Viral symptoms indicative of Iris yellow spot virus (IYSV) were observed on onion in several fields near Chenaran in Khorasan Razavi Province. Mechanical inoculation of herbaceous hosts with onion sap extracts from symptomatic plants showed similar symptoms to those described for IYSV. The mechanically transmitted virus reacted only with antisera specific to IYSV in DAS-ELISA but not with antisera specific

Research paper thumbnail of Surgical approach to the rostral cranial fossa by radical transfrontal craniotomy in the dog

Journal of the South African Veterinary Association, Mar 1, 1982

To overcome the problems of restricted visibility and surgical mobility, as well as those posed b... more To overcome the problems of restricted visibility and surgical mobility, as well as those posed by anatomical features oif the canine subfrontal sinus region and associated dura mater, aggravated by hazards of infection from potentially infected frontal sinuses, of uncontrollable haemorrhage and post-operative brain compression, a radical approach was devised, combining invasion of the frontal sinus with a lateral rostrotentorial craniotomy. This offers adequate surgical manoeuvring space, excellent visualisation of the rostral cranial fossa and its contents, proper asepsis, minimal haemorrhage and no untoward after-effects. The technique lends itself to diverse neurosurgical applications in the rostral cranial fossa of the dog. Particulars of instrumentation, and pre-operative, operative and post-operative procedures, done on 3 Beagles with excellent results, are described.

Research paper thumbnail of Differential Susceptibilities between Leaf Disks and Plants in the Transmission of Tomato Spotted Wilt Virus by Frankliniella occidentalis to TSWV Hosts and Transgenic Plants

Journal of Phytopathology, Oct 1, 1996

Research paper thumbnail of Establishment of cell cultures of two thrips species and their application in studies on tospovirus-vector interactions

Research paper thumbnail of Determining levels of resistance to Tulip Breaking Virus (TBV) in tulip (Tulipa L.) cultivars

Euphytica, 1991

The resistance of seven tulip cultivars to tulip breaking virus (TBV) was studied after mechanica... more The resistance of seven tulip cultivars to tulip breaking virus (TBV) was studied after mechanical inoculation by determining the number of infected plants and the level of virus in these plants over a period of one and a half years. Three cultivars (‘Apeldoorn’, ‘Kees Nelis’ and ‘Lustige Witwe’) appeared to be susceptible. Four cultivars (‘Cantata’, ‘Juan’, ‘Madame Lefeber’ and ‘Princeps’)

Research paper thumbnail of Variation in tospovirus transmission between populations of Frankliniella occidentalis (Thysanoptera: Thripidae)

Bulletin of Entomological Research, 1999

Fourteen populations of the western flower thrips Frankliniella occidentalis Pergande, originatin... more Fourteen populations of the western flower thrips Frankliniella occidentalis Pergande, originating from different hosts and countries in Asia, Europe, North America and New Zealand, were analysed for their competency and efficiency to transmit tomato spotted wilt virus (TSWV). All populations acquired and subsequently transmitted the virus, and were thus competent to transmit. They show marked differences in their efficiency, expressed as the percentage of transmitting adults. Efficiencies varied from 18% for a F. occidentalis population from the USA (US2) to 75% for a population from Israel (IS2). The differences between populations were not affected by the amount of virus ingested or by the host plant used. However, the tospovirus species studied and age at which the larvae acquired the virus affected the efficiency to transmit. First instar larvae of the NL3 population from The Netherlands were able to acquire tomato spotted wilt virus, whereas second instar larvae failed to do s...

Research paper thumbnail of Molecular characterization of cucurbit aphid-borne yellows virus isolates associated with 'namamarako' in the Philippines and 'Mara ba' in Thailand

Research paper thumbnail of Characterization of Tomato spotted wilt virus from Paprika in Korea

The Plant Pathology Journal, 2004

Research paper thumbnail of Characterization of a Tospovirus Isolate of Iris Yellow Spot Virus Associated with a Disease in Onion Fields in Brazil

Plant Disease, 1999

A tospovirus from onion causing a disease known as “sapeca” by growers in Brazil was characterize... more A tospovirus from onion causing a disease known as “sapeca” by growers in Brazil was characterized. Symptoms on onion consisted of numerous eyelike spots on the leaves and flower stalks resulting in flower abortion. Nicotiana benthamiana and N. rustica were the only systemic hosts experimentally found. Double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) experiments demonstrated that this virus was serologically related to iris yellow spot virus (IYSV), a tospovirus recently described in the Netherlands. This virus, from onion, based on an amino acid sequence identity of 90.5% for the N gene protein, is regarded as a strain of IYSV and is designated IYSVBR This 10% divergence in the nucleocapsid protein may represent an adaptation of the virus to distinct ecological niches.

Research paper thumbnail of Genome structure and sequence analysis of the tomato spotted wilt virus genome

Research paper thumbnail of Morphogenesis of sonchus yellow net virus in cowpea protoplasts

Journal of ultrastructure …, 1985

... Nikolai AM van Beek 1 , Dick Lohuis, Jeanne Dijkstra and Dick Peters Corresponding Author Con... more ... Nikolai AM van Beek 1 , Dick Lohuis, Jeanne Dijkstra and Dick Peters Corresponding Author Contact Information. ... of major ultrastructural changes consisted of appearance in the nucleus, 10 hr after inoculation, of a granular matrix with coiled nucleocapsid strands at its edge ...

Research paper thumbnail of Symptomatology and serology of plum pox virus isolates using antibodies to the N-termini of coat protein

Research paper thumbnail of Investigation of two polyclonal antisera to plum pox virus recovered at different stages after immunization

Research paper thumbnail of Rapid Technique for Determining Greenbug (Homoptera: Aphididae) Biotypes B, C, E, and F

Journal of Economic Entomology, 1988

A method for quickly determining greenbug, Schizaphis graminum (Rondani), biotypes B, C, E, and F... more A method for quickly determining greenbug, Schizaphis graminum (Rondani), biotypes B, C, E, and F was developed. 'Largo' resistance in 'TAM 105' x 'Largo' (5 x L), 'Triumph 64' (TR), 'TAM 107' (107), and 'CI 9058' was evaluated against biotype F so these host relationships could be compared to other biotypes. Mean damage ratings for 5 x L did not differ significantly from the susceptible checks, TR and 107. Therefore, only TR, 107, and 5 x L are needed to differentiate the biotypes. These cultivars were exposed for feeding exposure times of I, 2, 4, and 6 h to determine the time required for each biotype to make lesions. Feeding damage appeared as brown lesions on the leaves of susceptible plants. Lesions did not form on cultivars resistant to each biotype. Counts of lesions per leaf were made 24, 48, 72, and 96 h after infestation. All of the lesions that were to appear did so by 72 h after infestation. Some of the susceptible plants developed lesions at the 1-and 2-h feeding exposure. All of the susceptible plants formed lesions at the 4-and 6-h feeding times. Mean lesion numbers of 5.0 and 5.2 for 4 and 6 h, respectively, were not significantly different. Our technique permits biotype determinations to be made within 2 wk after aphid collection. Details on the construction of a clip cage, which is an integral part of the methodology, are provided.

Research paper thumbnail of Determination of the Median Latent Period of Two Tospoviruses in Frankliniella occidentalis, Using a Novel Leaf Disk Assay

Research paper thumbnail of Decreased preference and reproduction, and increased mortality of Frankliniella occidentalis on thrips-resistant pepper plants

Entomologia Experimentalis et Applicata, 2004

The effect of thrips resistance in pepper (Capsicum annuum L.) previously shown to result in impe... more The effect of thrips resistance in pepper (Capsicum annuum L.) previously shown to result in impeded thrips population development (Maris PC, Joosten NN, Goldbach RW & Peters D (2003a) Restricted spread of Tomato spotted wilt virus in thrips-resistant pepper. Phytopathology 93: 12231227. Maris PC, Joosten NN, Goldbach RW & Peters D (2003b) Spread of Tomato spotted wilt virus and population

Research paper thumbnail of Serological differentiation of 20 isolates of tomato spotted wilt virus

Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing f... more Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing five different procedures using a rabbit polyclonal antiserum against nucleocapsid proteins (NuAbR) and mouse monoclonal antibodies (MAbs), two directed to nucleocapsid proteins (N1 and N2) and four directed to glycoproteins G1 to G4. All the antisera were raised against TSWV-CNPH1. The 20 isolates were differentiated into two distinct serogroups. Serogroup I consisting of 16 isolates strongly reacted with NuAbR. The other four isolates were poorly recognized by NuAbR and were placed in another serogroup, designated II. The panel of MAbs differentiated the TSWV isolates into three serotypes. The 16 isolates forming serogroup I reacted strongly with the MAbs generated and were identified as serotype I isolates. The four isolates which made up serogroup II were split into serotypes II and III. The serotype II isolates did not respond or responded poorly with MAbs N1, N2 and G3. The two other isolates placed in serotype III were recognized by N1 but not by N2 and G3. Two isolates became defective after several mechanical passages and failed to respond or responded very poorly with MAbs directed to glycoproteins. Our results show that ELISA employing polyclonal and monoclonal antisera is a useful tool to differentiate TSWV isolates and to detect defective forms. The results also strongly suggest that TSWV nucleocapsid proteins are less conserved than the glycoproteins.

Research paper thumbnail of Serological differentiation of 20 isolates of tomato spotted wilt virus

Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing f... more Twenty tomato spotted wilt virus (TSWV) isolates were serologically compared in ELISA employing five different procedures using a rabbit polyclonal antiserum against nucleocapsid proteins (NuAbR) and mouse monoclonal antibodies (MAbs), two directed to nucleocapsid proteins (N1 and N2) and four directed to glycoproteins G1 to G4. All the antisera were raised against TSWV-CNPH1. The 20 isolates were differentiated into two distinct serogroups. Serogroup I consisting of 16 isolates strongly reacted with NuAbR. The other four isolates were poorly recognized by NuAbR and were placed in another serogroup, designated II. The panel of MAbs differentiated the TSWV isolates into three serotypes. The 16 isolates forming serogroup I reacted strongly with the MAbs generated and were identified as serotype I isolates. The four isolates which made up serogroup II were split into serotypes II and III. The serotype II isolates did not respond or responded poorly with MAbs N1, N2 and G3. The two other isolates placed in serotype III were recognized by N1 but not by N2 and G3. Two isolates became defective after several mechanical passages and failed to respond or responded very poorly with MAbs directed to glycoproteins. Our results show that ELISA employing polyclonal and monoclonal antisera is a useful tool to differentiate TSWV isolates and to detect defective forms. The results also strongly suggest that TSWV nucleocapsid proteins are less conserved than the glycoproteins.

Research paper thumbnail of Hypocomplementæmic Membranoproliferative Glomerulonephritis and Nephrotic Syndrome Associated with Partial Lipodystrophy of the Face and Trunk

Proceedings of the Royal Society of Medicine

Research paper thumbnail of Spread of Tomato spotted wilt virus and population development of Frankliniella occidentalis in pepper resistant to thrips

The effect of thrips resistance on both the spread of Tomato spotted wilt virus (TSWV) and the po... more The effect of thrips resistance on both the spread of Tomato spotted wilt virus (TSWV) and the population development of its major vector Frankliniella occidentalis was analysed on resistant and susceptible pepper (Capsicum) accessions. After release of viruliferous thrips, spread of TSWV was significantly lower in the primary and delayed in the secondary infection phase in plots with the thrips-resistant accession CPRO-1 compared to plots with the thrips susceptible accession Pikante Reuzen. Similar results were obtained in plots with a 1:1 mixture of plants of both accessions. Spread to the virus-resistant accessions PI 152225 and PI 159236, resistant and susceptible to thrips, respectively, was delayed in the secondary phase to plants of the former accession. Since the delay of the infection in the plots with thrips-resistant plants could only partly be explained by an impeded development of thrips populations, other factors, probably related to the behaviour of thrips, also affect the transmission of TSWV to the resistant plants. The results obtained indicate that thrips resistance in pepper can be a useful tool in IPM strategies to control TSWV infections.

Research paper thumbnail of Molecular Diagnosis of Iris Yellow Spot Virus (IYSV) on Onion in Iran

Journal of Agricultural Science and Technology, 2012

Viral symptoms indicative of Iris yellow spot virus (IYSV) were observed on onion in several fiel... more Viral symptoms indicative of Iris yellow spot virus (IYSV) were observed on onion in several fields near Chenaran in Khorasan Razavi Province. Mechanical inoculation of herbaceous hosts with onion sap extracts from symptomatic plants showed similar symptoms to those described for IYSV. The mechanically transmitted virus reacted only with antisera specific to IYSV in DAS-ELISA but not with antisera specific

Research paper thumbnail of Surgical approach to the rostral cranial fossa by radical transfrontal craniotomy in the dog

Journal of the South African Veterinary Association, Mar 1, 1982

To overcome the problems of restricted visibility and surgical mobility, as well as those posed b... more To overcome the problems of restricted visibility and surgical mobility, as well as those posed by anatomical features oif the canine subfrontal sinus region and associated dura mater, aggravated by hazards of infection from potentially infected frontal sinuses, of uncontrollable haemorrhage and post-operative brain compression, a radical approach was devised, combining invasion of the frontal sinus with a lateral rostrotentorial craniotomy. This offers adequate surgical manoeuvring space, excellent visualisation of the rostral cranial fossa and its contents, proper asepsis, minimal haemorrhage and no untoward after-effects. The technique lends itself to diverse neurosurgical applications in the rostral cranial fossa of the dog. Particulars of instrumentation, and pre-operative, operative and post-operative procedures, done on 3 Beagles with excellent results, are described.

Research paper thumbnail of Differential Susceptibilities between Leaf Disks and Plants in the Transmission of Tomato Spotted Wilt Virus by Frankliniella occidentalis to TSWV Hosts and Transgenic Plants

Journal of Phytopathology, Oct 1, 1996

Research paper thumbnail of Establishment of cell cultures of two thrips species and their application in studies on tospovirus-vector interactions

Research paper thumbnail of Determining levels of resistance to Tulip Breaking Virus (TBV) in tulip (Tulipa L.) cultivars

Euphytica, 1991

The resistance of seven tulip cultivars to tulip breaking virus (TBV) was studied after mechanica... more The resistance of seven tulip cultivars to tulip breaking virus (TBV) was studied after mechanical inoculation by determining the number of infected plants and the level of virus in these plants over a period of one and a half years. Three cultivars (‘Apeldoorn’, ‘Kees Nelis’ and ‘Lustige Witwe’) appeared to be susceptible. Four cultivars (‘Cantata’, ‘Juan’, ‘Madame Lefeber’ and ‘Princeps’)