scholarly journals Assessments of the Edge Effect in Intensity of Potato Zebra Chip Disease

Plant Disease ◽  
2012 ◽  
Vol 96 (7) ◽  
pp. 943-947 ◽  
Author(s):  
F. Workneh ◽  
D. C. Henne ◽  
A. C. Childers ◽  
L. Paetzold ◽  
C. M. Rush
Keyword(s):  
The United States ◽  
Rank Test ◽  
Insect Vector ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Disease Progress ◽  
Zebra Chip Disease ◽  
Signed Rank ◽  
Signed Rank Test ◽  
Candidatus Liberibacter

Zebra chip is a newly emerging potato disease which imparts dark colorations on fried chips, rendering them unmarketable. The disease is associated with the phloem-limited proteobacterium ‘Candidatus Liberibacter solancearum’, vectored by the potato psyllid Bactericera cockerelli. First reported from Mexico in the mid-1990s, the disease was observed for the first time in Texas in 2000 and is now prevalent in several potato-producing regions of the United States. In this study, we were interested in investigating whether there are edge effects in zebra chip intensity that can be assessed as a “foot print” of the associated insect vector. In 2009, we conducted studies in three fields in the Texas Panhandle in paired plots of 10 by 20 m around the field edges and 100 m infield in which symptomatic plants were counted just before harvest. The number of plot pairs (edge and infield) ranged from 15 to 18 depending on the size of the fields. In a separate study, temporal disease progress was assessed in two fields around the edges of the center-pivot circle in approximately 10-by-450-m areas. In 2010, the paired plot studies were repeated in 10 potato fields in Texas, Kansas, and Nebraska. Zebra chip intensity data from the paired-plot studies for both years were analyzed using the Wilcoxon's signed-rank test, a nonparametric equivalent of the classical (parametric) paired t test. In the 2009 study in all three fields, the edge plots had significantly greater zebra chip intensity than the infield plots (P < 0.05). Edge plots in the 2010 study also had greater zebra chip intensity in all fields and the differences were significant in the majority of fields (P < 0.05). In the diseases progress study in both fields, weekly zebra chip intensity on the edges reached its maximum after the third week of its first detection, and the disease progress curves were best fitted with the second-degree polynomial (quadratic) for both fields. The 2-year study clearly demonstrated that zebra chip intensity in potato fields was greater on the edges than in the infields. This finding has significant implications for psyllid management because greater emphasis in psyllid control strategy can be directed toward the edges for better results.

scholarly journals A field study of Bactericera cockerelli feeding timing in potato crops

2017 ◽  
Vol 70 ◽  
pp. 320
Author(s):  
J.N. Furlong ◽  
J. Vereijssen ◽  
A.R. Pitman ◽  
R.C. Butler
Keyword(s):  
Growth Stages ◽  
Insect Vector ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Growing Seasons ◽  
Yield And Quality ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter ◽  
Potato Crops ◽  
Different Growth Stages

Since its 2006 detection in New Zealand, the tomato potato psyllid (TPP), Bactericera cockerelli, has been responsible for yield and quality-reducing damage to potatoes as well as to other solanaceous crops. TPP is best known as the insect vector for the zebra chip disease-associated bacterium Candidatus Liberibacter solanacearum (CLso), but feeding by CLso-negative TPP on potatoes is also linked to damaging effects. An improved understanding of which potato plant physiological stages are most affected by feeding of CLso-negative TPP will allow for more directed integrated pest management (IPM) plans. As part of a two-year repeated eld study to assess the effect of TPP feeding timing on potatoes, CLso-negative TPP were released into mesh cages over outdoor potato (‘Moonlight’) plantings at ve different growth stages: post-emergence, owering, post- owering, late-season, and pre-harvest. Tubers were grouped by plant at harvest. (Un)marketable numbers and weights, marketable dry matter and zebra chip severity were determined. Results from this trial and other shadehouse trials conducted previously are still being analysed but have the potential to better target IPM plans and reduce costly, labour-intensive, and environmentally impactful pesticide spray use, which is currently relied on heavily throughout growing seasons.

scholarly journals Transmission Efficiency of ‘Candidatus Liberibacter solanacearum’ and Potato Zebra Chip Disease Progress in Relation to Pathogen Titer, Vector Numbers, and Feeding Sites

2012 ◽  
Vol 102 (11) ◽  
pp. 1079-1085 ◽  
Author(s):  
A. Rashed ◽  
T. D. Nash ◽  
L. Paetzold ◽  
F. Workneh ◽  
C. M. Rush
Keyword(s):  
Plant Pathogens ◽  
Transmission Efficiency ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Candidatus Liberibacter Solanacearum ◽  
Feeding Site ◽  
Disease Progress ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter ◽  
Inoculation Study

With diseases caused by vector-borne plant pathogens, acquisition and inoculation are two primary stages of the transmission, which can determine vector efficiency in spreading the pathogen. The present study was initiated to quantify acquisition and inoculation successes of ‘Candidatus Liberibacter solanacearum’, the etiological agent of zebra chip disease of potato, by its psyllid vector, Bactericera cockerelli (Hemiptera: Triozidae). Acquisition success was evaluated in relation to feeding site on the host plant as well as the acquisition access period. Inoculation success was evaluated in relation to vector number (1 and 4) on the plants. Acquisition success was influenced by the feeding site on the plant. The highest acquisition success occurred when insects had access to the whole plant. The results of the inoculation study indicated that the rate of successfully inoculated plants increased with the vector number. Plants inoculated with multiple psyllids had higher bacterial titer at the point of inoculation. Although disease incubation period was significantly shorter in plants inoculated with multiple psyllids, this effect was heterogeneous across experimental blocks, and was independent of pathogen quantity detected in the leaflets 3 days postinoculation. Disease progress was not affected by bacterial quantity injected or psyllid numbers.

scholarly journals Relative Abundance of Potato Psyllid Haplotypes in Southern Idaho Potato Fields During 2012 to 2015, and Incidence of ‘Candidatus Liberibacter solanacearum’ Causing Zebra Chip Disease

Plant Disease ◽  
2017 ◽  
Vol 101 (5) ◽  
pp. 822-829 ◽  
Author(s):  
Jennifer Dahan ◽  
Erik J. Wenninger ◽  
Brandon Thompson ◽  
Sahar Eid ◽  
Nora Olsen ◽  
...  
Keyword(s):  
Potato Industry ◽  
Potato Psyllid ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Spatial And Temporal Patterns ◽  
Candidatus Liberibacter Solanacearum ◽  
South Central ◽  
Zebra Chip Disease ◽  
Four Seasons ◽  
Candidatus Liberibacter

Zebra chip (ZC) disease, a serious threat to the potato industry, is caused by the bacterium ‘Candidatus Liberibacter solanacearum’ (Lso). Five haplotypes (hapA to hapE) of this pathogen have been described so far in different crops, with only hapA and hapB being associated with ZC in potato. Both haplotypes are vectored and transmitted to a variety of solanaceaeous plants by the tomato/potato psyllid, Bactericera cockerelli (Šulc). Psyllids are native to North America, and four haplotypes have been identified and named based on their predominant geographic association: Northwestern, Central, Western, and Southwestern. Although all psyllid haplotypes have been found in southern Idaho potato fields, data on relative haplotype abundances and dynamic changes in the fields over time have not previously been reported. Here, psyllid samples collected in Idaho potato fields from 2012 to 2015 were used to clarify spatial and temporal patterns in distribution and abundance of psyllid and Lso haplotypes. A shift from hapA toward hapB population of Lso was revealed during these four seasons, indicating possible evolution of Lso in Idaho fields. Although we confirmed that Western psyllids were the most abundant by far during the four seasons of observation, we also observed changes in abundance of other haplotypes, including increased diversity of psyllid haplotypes during 2015. Seasonal changes observed for the Northwestern and Central haplotypes could potentially be linked to psyllid migration and/or habitat changes. South-central Idaho exhibited more diversity in psyllid haplotypes than southwestern Idaho.

scholarly journals A New ‘Candidatus Liberibacter’ Species in Solanum tuberosum in New Zealand

Plant Disease ◽  
2008 ◽  
Vol 92 (10) ◽  
pp. 1474-1474 ◽  
Author(s):  
L. W. Liefting ◽  
Z. C. Perez-Egusquiza ◽  
G. R. G. Clover ◽  
J. A. D. Anderson
Keyword(s):  
Solanum Tuberosum ◽  
New Zealand ◽  
Vascular Tissue ◽  
Economic Damage ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
16S Rrna Sequence ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter ◽  
Total Dna

Symptoms resembling “zebra chip” disease (3) were observed in potato (Solanum tuberosum) tubers harvested from a breeding trial in South Auckland, New Zealand in May 2008. The tubers had necrotic flecking and streaking that became marked when the potatoes were fried. Affected plants generally senesced early, at the beginning of April. The mean yield was approximately 60% less than expected and harvested tubers had less dry matter (13%) than normal (19%). Large numbers of the psyllid Bactericera cockerelli were observed on the crop during the summer. Total DNA was extracted from the vascular tissue of five symptomatic tubers and seven volunteers collected from the affected field with a DNeasy Plant Mini Kit (Qiagen, Valencia, CA). Samples were tested by PCR using primers OA2 (GenBank Accession No. EU834130) and OI2c (2). These primers amplify a 1,160-bp fragment of the 16S rRNA sequence of a ‘Candidatus Liberibacter’ species identified in tomato and capsicum in New Zealand. No fragment was amplified from healthy plants, but amplicons of the expected size were obtained from all symptomatic tubers and one plant. A 650-bp fragment of the β operon was also amplified from symptomatic tubers. The amplicons were directly sequenced (GenBank Accession Nos. EU849020 and EU919514). BLAST analysis showed 100% identity to the tomato/capsicum liberibacter (GenBank Accession Nos. EU834130 and EU834131). From a commercial potato field adjoining the breeding trial, groundkeeper tubers were collected and separated into those that were asymptomatic and those that exhibited a range of symptoms. Total DNA was extracted and tested by PCR using the OA2/OI2c primers. In the first category, 6 of 10 tubers tested positive, whereas the 10 tubers in the second category tested negative. Two phytoplasmas seem to be involved in the “zebra chip” disease complex (4) but were not detected in the samples in this study. To our knowledge, this is the first report of a liberibacter associated with disease in potato. From transmission electron microscope observations, previous researchers have hypothesized that a bacterium-like organism may cause “zebra chip” (1) and B. cockerelli is associated with the disease (3). “Zebra chip” was first reported in Mexico in 1994, since then it has caused significant economic damage in Guatemala, Mexico, and the southwestern United States. The economic impact of the disease in New Zealand is yet to be determined. References: (1) S. H. De Boer et al. Page 30 in: New and Old Pathogens of Potato in Changing Climate. A. Hannukkala and M. Segerstedt, eds. Online publication. Agrifood Research Working Paper 142, 2007. (2) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (3) J. E. Munyaneza et al. J. Econ. Entomol. 100:656, 2007. (4) G. A. Secor et al. Plant Dis. 90:377, 2006.

scholarly journals Characterization and Epidemiological Significance of Potato Plants Grown from Seed Tubers Affected by Zebra Chip Disease

Plant Disease ◽  
2010 ◽  
Vol 94 (6) ◽  
pp. 659-665 ◽  
Author(s):  
D. C. Henne ◽  
F. Workneh ◽  
A. Wen ◽  
J. A. Price ◽  
J. S. Pasche ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
Zebra Chip ◽  
Candidatus Liberibacter Solanacearum ◽  
Potato Plants ◽  
Seed Tubers ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter ◽  
Epidemiological Significance

An emerging disease of potato in the United States, known as “Zebra Chip” or “Zebra Complex” (ZC), is increasing in scope and threatens to spread further. Here, we report on studies performed to understand the role of tuberborne ZC in the epidemiology of this disease. Depending on variety, up to 44% of ZC-affected seed tubers (ZCST) were viable, producing hair sprouts and weak plants. Chip discoloration in progeny tubers of ZCST was more severe than those from ZC-asymptomatic seed tubers but varied depending on whether progeny tubers or foliage were positive or negative for ‘Candidatus Liberibacter solanacearum’. A low percentage of greenhouse-grown plants produced by ZCST tested positive for ‘Ca. Liberibacter’. No adult potato psyllids became infective after feeding upon these plants but they did acquire ‘Ca. Liberibacter’ from field-grown plants produced by ZCST. Plants with new ZC infections near plants produced by ZCST were not significantly different from healthy plants, whereas plants affected with ZC from infectious potato psyllids had significantly more ZC infections near either plants produced by ZCST or healthy plants. We conclude that, in areas where ZC is currently established, plants produced by ZCST do not significantly contribute to ZC incidence and spread within potato fields.

scholarly journals First Report of Zebra Chip Disease and “Candidatus Liberibacter solanacearum” on Potatoes in Idaho

Plant Disease ◽  
2012 ◽  
Vol 96 (3) ◽  
pp. 453-453 ◽  
Author(s):  
J. M. Crosslin ◽  
N. Olsen ◽  
P. Nolte
Keyword(s):  
16S Rdna ◽  
The United States ◽  
Zebra Chip ◽  
Candidatus Liberibacter Solanacearum ◽  
Russet Norkotah ◽  
Sequence Identity ◽  
South Central ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter ◽  
Central Idaho

In September 2011, potato (Solanum tuberosum L.) tubers graded in a packing facility in south-central Idaho were observed with internal discolorations suggestive of zebra chip disease (ZC). Symptoms were observed in 1 to 2% of tubers of cv. Russet Norkotah and included brown spots and streaks especially in and near the vascular tissue. Some tubers also showed a dark and sunken stolon attachment typical of ZC (1). Initially, tissue samples were taken from seven symptomatic tubers and tested by PCR for “Candidatus Liberibacter solanacearum”, the bacterium associated with ZC. Primers specific for the 16S rDNA (primers CLipoF [4] and OI2c [3]) and the outer membrane protein (OMB 1482f and 2086r) (2) were used. Six of these samples were positive for the bacterium. The amplified 16S rDNA and OMB products from two symptomatic tubers of cv. Russet Norkotah were cloned and three clones of each were sequenced. The 16S sequences (1,071 bp; GenBank Accession Nos. JN848755 and JN848756) from the two tubers varied by one nucleotide and had 99 to 100% sequence identity to numerous “Ca. L. solanacearum” sequences in GenBank (e.g., Accession Nos. HM246509, FJ957897, and EU935004). Sequences of the two OMB clones (605 bp; GenBank Accession Nos. JN848757 and JN848758) had 97% sequence identity to the two “Ca. L. solanacearum” OMB sequences in GenBank (Accession Nos. CP002371 and FJ914617). Six of eight additional symptomatic field-collected cv. Russet Norkotah tubers corresponding to tubers collected in the packing facility were also positive for “Ca. L. solanacearum” by PCR. Additional severely symptomatic tubers of cvs. Russet Burbank, Yukon Gold, and raw cut French fries of Ranger Russet produced in south-central Idaho were subsequently tested by PCR and were found to be positive for “Ca. L. solanacearum” as well. On the basis of the symptoms, specific PCR amplification with two distinct primer pairs and DNA sequence analysis, zebra chip disease caused by “Ca. L. solanacearum” was determined to be present in Idaho. This disease has caused significant economic damage to potatoes in many regions, including Texas, Mexico, Central America, and New Zealand (1). Idaho is the largest potato-producing state in the United States, with over 150,000 ha planted this year, and therefore, ZC potentially poses a significant risk to agriculture in this state. References: (1) J. M. Crosslin et al. Online publication. doi:10.1094/PHP-2010-0317-01-RV, Plant Health Progress, 2010. (2) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (4) G. A. Secor. Plant Dis. 93:574, 2009.

scholarly journals Seasonal Occurrence of Potato Psyllid (Bactericera Cockerelli) and Risk of Zebra Chip Pathogen (Candidatus Liberibacter Solanacearum) in Northwestern New Mexico

Insects ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 3
Author(s):  
Koffi Djaman ◽  
Charles Higgins ◽  
Shantel Begay ◽  
Komlan Koudahe ◽  
Samuel Allen ◽  
...  
Keyword(s):  
New Mexico ◽  
Pest Management ◽  
Growing Season ◽  
Management Decision ◽  
Potato Psyllid ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Candidatus Liberibacter Solanacearum ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter

Potato psyllid (Bactericera cockerelli) is one of the most important pests in potatoes (Solanum tuberosum L.) due to its feeding behavior and the transmission of a bacterium (Candidatus Liberibacter solanacearum) that causes zebra chip disease, altering the quality of the potato tuber and the fried potato chip or french fry. This pest is thus a threat to the chip potato industry and often requires preventive measures including the use of costly insecticides. The objectives of this research were to monitor the variation in B. cockerelli adult abundance and to evaluate the risk of zebra chip disease in northwestern New Mexico, USA. Yellow sticky traps were used to collect the pest at the Agricultural Experiment Station at Farmington, NM and in nearby commercial fields at the Navajo Agricultural Products Industry (NAPI) and Navajo Mesa Farms during the 2017–2019 period. The collected adult pests were analyzed at Texas A & M University for the presence of Candidatus L. solanacearum (Lso). The results showed field infestation by B. cockerelli in early June and that the population peaked during the second half of July and decreased as the potato growing season progressed. However, a second less important peak of the pest was revealed around mid- to late-August, depending on the growing season and field. While the B. cockerelli population increased linearly with average air temperature, it showed strong third order polynomial relationships with the accumulated thermal units and the Julian days. The test of B. cockerelli for the Lso infection revealed a low incidence of the pathogen varying from 0.22% to 6.25% and the infected adult B. cockerelli were collected during the population peak period. The results of this study may be helpful to potato growers in pest management decision-making and control. However, more study is needed to evaluate zebra chip disease in terms of its prevention and economic impact, and to develop economic thresholds and pest management programs for northwestern New Mexico and neighboring regions.

scholarly journals Zebra Chip Disease and Potato Biochemistry: Tuber Physiological Changes in Response to ‘Candidatus Liberibacter solanacearum’ Infection Over Time

2013 ◽  
Vol 103 (5) ◽  
pp. 419-426 ◽  
Author(s):  
A. Rashed ◽  
C. M. Wallis ◽  
L. Paetzold ◽  
F. Workneh ◽  
C. M. Rush
Keyword(s):  
Symptom Severity ◽  
Potato Production ◽  
The United States ◽  
Zebra Chip ◽  
Defense Proteins ◽  
Candidatus Liberibacter Solanacearum ◽  
Polyphenol Oxidases ◽  
Biochemical Responses ◽  
Zebra Chip Disease ◽  
Candidatus Liberibacter

Zebra chip disease, putatively caused by the bacterium ‘Candidatus Liberibacter solanacearum’, is of increasing concern to potato production in Mexico, the United States, and New Zealand. However, little is known about the etiology of this disease and changes that occur within host tubers that result in its symptoms. Previous studies found that increased levels of phenolics, amino acids, defense proteins, and carbohydrates in ‘Ca. L. solanacearum’-infected tubers are associated with symptoms of zebra chip. This study was conducted to quantify variations in levels of these biochemical components in relation to the time of infestation, symptom severity, and ‘Ca. L. solanacearum’ titer. Levels of phenolics, peroxidases, polyphenol oxidases, and reducing sugars (glucose and, to some extent, fructose) changed during infection, with higher levels occurring in tubers infected at least 5 weeks before harvest than in those infected only a week before harvest and those of controls. Compared with the apical tuber ends, greater levels of phenolics, peroxidases, and sucrose occurred at the basal (stolon attachment) end of infected tubers. With the exception of phenolics, concentrations of the evaluated compounds were not associated with ‘Ca. L. solanacearum’ titer. However, there were significant associations between biochemical responses and symptom severity. The lack of a linear correlation between most plant biochemical responses and ‘Ca. L. solanacearum’ titer suggests that shifts in metabolic profiles are independent of variations in ‘Ca. L. solanacearum’ levels.

scholarly journals Silverleaf Nightshade (Solanum elaeagnifolium), a Reservoir Host for ‘Candidatus Liberibacter solanacearum’, the Putative Causal Agent of Zebra Chip Disease of Potato

Plant Disease ◽  
2015 ◽  
Vol 99 (7) ◽  
pp. 910-915 ◽  
Author(s):  
Jenita Thinakaran ◽  
Elizabeth Pierson ◽  
Madhurababu Kunta ◽  
Joseph E. Munyaneza ◽  
Charlie M. Rush ◽  
...  
Keyword(s):  
Pathogen Transmission ◽  
Potato Psyllid ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
Candidatus Liberibacter Solanacearum ◽  
Zebra Chip Disease ◽  
Commercial Potato ◽  
Silverleaf Nightshade ◽  
Candidatus Liberibacter ◽  
Solanum Elaeagnifolium

Zebra chip disease of potato is caused by the bacterial pathogen ‘Candidatus Liberibacter solanacearum’ and is a growing concern for commercial potato production in several countries in North and Central America and New Zealand. ‘Ca. L. solanacearum’ is vectored by the potato psyllid Bactericera cockerelli, which transmits the pathogen to several cultivated and wild solanaceaous host plants. Silverleaf nightshade (SLN), Solanum elaeagnifolium, is a common weed in the Lower Rio Grande Valley of Texas and a host for both the potato psyllid and ‘Ca. L. solanacearum’. SLN plants were successfully inoculated with ‘Ca. L. solanacearum’ under laboratory conditions. Retention studies demonstrated that ‘Ca. L. solanacearum’-infected SLN planted in the field in January 2013, concurrent with commercial potato planting, retained the pathogen under field conditions throughout the year despite extensive dieback during summer. The presence of ‘Ca. L. solanacearum’ was confirmed in leaves, roots, and stolons of SLN plants collected the following year using polymerase chain reaction. Acquisition assays using B. cockerelli adults also revealed that SLN retained the pathogen. Transmission studies determined that B. cockerelli can acquire ‘Ca. L. solanacearum’ within a 2-week acquisition access period on ‘Ca. L. solanacearum’-infected SLN and subsequently transmit the pathogen to potato. These results demonstrate that SLN plants can serve as a reservoir for ‘Ca. L. solanacearum’, providing a source of inoculum for B. cockerelli adults colonizing potato the next season. The presence of SLN plants all year round in the LRGV makes the weed an epidemiologically important host. These findings underscore the importance of eradicating or managing SLN plants growing in the vicinity of potato fields to prevent spread of ‘Ca. L. solanacearum’ and damage caused by zebra chip.

scholarly journals The rise and rise of Bactericera cockerelli in potato crops in Canterbury

2015 ◽  
Vol 68 ◽  
pp. 85-90
Author(s):  
J. Vereijssen ◽  
A.M. Barnes ◽  
N.A. Berry ◽  
G.M. Drayton ◽  
J.D. Fletcher ◽  
...  
Keyword(s):  
Processing Plant ◽  
Bactericera Cockerelli ◽  
Zebra Chip ◽  
The North ◽  
Plant Infection ◽  
Zebra Chip Disease ◽  
Commercial Potato ◽  
Candidatus Liberibacter ◽  
Potato Crops ◽  
First Time

Tomato potato psyllid (TPP) Bactericera cockerelli (Scaron;ulc) (Hemiptera Triozidae) was first recorded in the North Island of New Zealand in 2006 Three years later the insect was found in the Oamaru area (South Island) Over the years there has been a rise in TPP numbers trapped in potato crops in Canterbury (South Island) Recently increased prevalence and severity of foliar and tuber symptoms related to plant infection with Candidatus Liberibacter solanacearum (CLso) vectored by TPP have been observed in trials and in commercial potato crops Moreover in the 201314 season the resulting zebra chip disease was observed for the first time in tubers at a processing plant in Canterbury It is concluded that Canterbury has a landscape where hosts are available yearround and a climate that does not seem to hinder TPP development The aim of this paper is to present a stocktake of TPP in Canterbury

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