The draft genome sequences of three “Candidatus Symbiopectobacterium” isolates that were collected from New Zealand-grown potato tubers represent the first report of this proposed taxon in the Southern Hemisphere. Their symbiosis with insects and nematodes and their presence on plants may lead to new strategies for pest control and crop management.

Fusarium basal rot, caused by Fusarium oxysporum f.sp. cepae, is an important onion disease worldwide. Greenhouse pot experiments were conducted during two growing seasons to determine if field soils from New Zealand's main onion growing regions had different fusarium basal rot suppressive capabilities, and identified factors involved in disease suppression This study demonstrated that soils naturally suppressive to fusarium basal rot were present in New Zealand and that soil organic matter content, total soil carbon, total nitrogen and soil phosphorous concentrations were associated with disease incidence. Soil microorganisms were shown to be involved in disease suppression since when they were eliminated or reduced by soil heat treatment, fusarium basal rot incidence markedly increased. This study provided an increased understanding of how soil physical, chemical and biological factors affect the suppressiveness of selected New Zealand soils to fusarium basal rot of onion, and demonstrated that certain bacterial and fungal taxa may be involved in suppression of this disease.

Tomato potato psyllid (TPP), Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), is the vector for “Candidatus Liberibacter solanacearum” (CLso), which causes the serious disease “zebra chip” (ZC) of potatoes. Between 2016 and 2019, a reduced-insecticide approach to control TPP was evaluated. We compared a standard-insecticide weekly spray regime that included Integrated Pest Management (IPM)-compatible insecticides plus JMS Stylet Oil® (JMS) as a wetting agent, with a reduced-insecticide regime where we used the oil on its own on alternate weeks with the insecticide/oil mixtures. Spray programme start dates were determined by: (1) crop scouting; (2) sticky-trap monitoring; and (3) degree-day calculation. Crop scouting combined with a sticky-trap action threshold and degree-day data was an effective method for determining when to start spraying. The most substantial reduction in insecticides was achieved by alternating weekly insecticides with the oil formulation on its own. Sub-samples of TPP from sticky traps situated in the trials tested for CLso confirmed the presence of the bacteria in (commonly known as ‘hot’) TPP throughout the trials. The reduced-treatment approach gave statistically similar levels of ZC to the standard insecticide spray programme.

Soils in which disease fails to develop despite pathogen presence are considered disease-suppressive. They offer sustainable, effective protection to plants against infection by soil-borne pathogens. Naturally disease-suppressive soils have been reported for diseases of a diverse range of agricultural crops worldwide yet the underlying mechanisms of disease suppression are still not completely understood. Two large greenhouse experiments, conducted during 2017/18 (Year 1) and 2018/19 (Year 2), determined that soils naturally suppressive to stem canker and black scurf of potato (caused by Rhizoctonia solani) are present in vegetable-arable cropping soils of the Auckland and Waikato regions of New Zealand. Soil was pre-treated with heat prior to inoculation with R. solani and compared with untreated and uninoculated controls to ascertain if stem canker and black scurf suppression was ‘general’, or ‘specific’ (i.e. transferable; possibly involving specific microorganisms). Rhizoctonia solani inoculation was also combined with transfer of one part test soil to nine parts of a known disease-conducive soil. Abiotic factors such as soil texture and organic matter content influenced black scurf incidence and severity. Soil microorganisms were also involved in disease suppression since black scurf incidence and severity markedly increased when they were eliminated or reduced by soil heat pre-treatment. Microbial profiling of the soils through sequencing revealed that taxa of geographically close soils of the same type had similar fungal and bacterial community structure and diversity even though they differed in their capacity to suppress black scurf. These results suggest that although the soil microbiome as a whole, was mainly responsible for soil disease suppressiveness, certain bacterial genera or species may play a role in black scurf suppression.

The purpose of this study was to assess the value of fMRI in addition to USS in evaluating fetal non-CNS abnormalities and whether information available from the fMRI would change diagnoses or alter patient management thus impacting on clinical care. In addition, the diagnostic accuracy and postnatal impact of both imaging methods were also assessed. Both prospective and retrospective assessment of all fetuses in second and third trimesters with suspected non-CNS abnormalities referred to our hospital for fMRI between November 2011 and February 2020. Two expert panel assessments were performed. The first expert panel analysed scans in an antenatal perspective to determine the value of fMRI in shaping patients' care pathways. The second expert panel analysed scans results in comparison to final postnatal outcome diagnoses. 481 fetuses with suspected non-CNS abnormalities were included. Study cohort was divided according to fetal body region involved into six groups. Chest (n = 132), GUS (n = 142), Abdomen (n = 128), Skeletal (n = 43), Neck (n = 13) and Miscellaneous (n = 23). Final comparison with postnatal outcome was achieved in 204 fetuses. Overall (second panel assessment) fMRI had a diagnostic accuracy of 87.7% compared to 69.6% of USS and it added information in 21.5% that was deemed to have changed diagnoses and/or management in 7.8%. Both scans diagnostic accuracies varied according to fetal body region with 100% accuracy for both in the neck cohort, chest (fMRI = 95.6%, USS = 81%), skeletal (fMRI = 92%, USS = 69%), abdomen (fMRI = 88%, USS = 69%), miscellaneous (fMRI = 83%, USS = 66.6%) and GUS (fMRI = 75.8%, USS = 53%). First expert panel assessment found that fMRI provided additional information in over 60% of the cases and that could have changed the diagnoses and/or management in 40%. fMRI provides high diagnostic accuracy in detecting fetal non-CNS pathologies especially fetal chest, abdomen and skeletal abnormalities. It also provides additional information to USS that is useful for clinical management both before and after delivery in all fetal body abnormalities.

Powdery scab, caused by Spongospora subterranea, is an important potato disease. Greenhouse experiments in 2017/18 and 2018/19 on (very susceptible) ‘Agria’ seed tubers assessed if field-collected soils had different powdery scab-suppressive capabilities and identified factors involved in disease suppression. 2017/18: 12 geographically diverse soils with either S. subterranea added at planting or not added; 2018/19: six single-type soils used, to determine if powdery scab suppression was ‘general’, or ‘specific’ (transferable; possibly involving microorganisms), and if suppression was associated with soil physical, chemical, or biological factors (bacteria/fungi). For both seasons, S. subterranea soil ammendment increased scab severity on harvested tubers in all soils but one. Powdery scab severity (percent tubers with > 5% surface area covered by scabs) ranged from 0 to 39%. Soil texture, pH, soil organic matter and nutrient contents were associated with powdery scab incidence for some soils but not others. Effects of previous crop rotations on powdery scab were variable: one soil with three recent previous potato crops in rotation was disease-suppressive. All 2018/19 soils displayed some microbe-mediated disease suppression, three being more suppressive than others. Two had possible ‘specific’ Spongospora suppression (less disease when added to the conducive soil). Thus Spongospora -suppressive soils are present in New Zealand, and abiotic and biotic soil factors influenced incidence/severity of powdery scab of potato.

To investigate the benefit of fetal MRI for non central nervous system (CNS) abnormalities in terms of patient management and counselling. A cohort study of pregnant women whose Fetuses had suspected non-CNS abnormalities on prenatal ultrasound (US) scan and had MRI. Comparison of fetal MRI and US information and impact on patient management/counselling was assessed jointly by experts in each specialty to reduce bias. Cases were graded from 1 to 6 based on the degree of agreement or disagreement and the impact that would have on management or counselling. Outcome data was retrieved from hospital notes. 488 participants between November 2011 and February 2019. The cohort was subdivided according to body area involved: chest (n = 147), abdomen (n = 129), genitourinary (n = 139), skeletal (n = 43), neck (n = 13) and miscellaneous (n = 17). Fetal MRI fundamentally changed diagnoses in 77 fetuses (15.7%), provided additional information that altered counselling and management plans in 108 (22%) fetuses and added information without changing either management or counselling in 117 fetuses (23.9%). Both prenatal imaging modalities provided similar information in 184 fetuses (37.7%). In chest cases MRI changed 59.8% and in abdominal cases 29.4%. Follow-up data (150 cases so far) from postnatal imaging or post mortem confirmed that MRI as correct in 82.6% (n = 124) and as incorrect in 3.3% (n = 5), US as correct in 62.6% (n = 94) and as incorrect in 7% (n = 10), MRI missed information that affected management/counselling in 6.6% (n = 10) and without effect in 6.6% (n = 10), US missed information that affected management/counselling in 10.6% (n = 16) and without effect in 19% (n = 29). Fetal MRI is a useful adjunct to ultrasound in the imaging of fetal non-CNS abnormalities, especially in chest or abdominal abnormalities.

Ceratocystis fimbriata was reported in 2010 causing wilt and death of kiwifruit (Actinidia spp.) vines in Brazil, with losses of up to 50% of vines on some orchards. New Zealand is one of the largest producers of kiwifruit in the world, but C. fimbriata has been recorded only on kumara (Ipomoea batatas) in this country. In this study the pathogenicity of New Zealand isolates of C. fimbriata from kumara was examined using potted vines of four kiwifruit cultivars. During the trial, none of the vines became visibly diseased, growth rates were not restricted, and discolouration at the inoculation sites on the stem was minimal. In comparison, tests by researchers in Brazil using C. fimbriata isolated from symptomatic kiwifruit resulted in lengthy lesions and death of susceptible kiwifruit seedlings. Sequences of the internal transcribed spacer (ITS) region of rRNA from the New Zealand C. fimbriata isolates were 100% identical to those sequences from C. fimbriata isolates from Ipomoea batatas in GenBank. This study has shown that the New Zealand isolates of C. fimbriata from kumara are not pathogenic to the kiwifruit cultivars tested, and are a different pathotype to those found on kiwifruit in Brazil.

Plant-pathogenic Verticillium species have been present in New Zealand for many years, and have been considered minor wilt pathogens of kiwifruit. However, an outbreak of Verticillium nonalfalfae (previously identified as Verticillium alboatrum) causing wilt and death of the kiwifruit cultivar Actinidia chinensis var. chinensis ‘Hort16A’ in Chile has raised questions around the pathogenicity and significance of New Zealand Verticillium species. This study investigated the pathogenicity of New Zealand isolates of Verticillium spp. to ‘Hort16A’. Three isolates of Verticillium dahliae and one of V. alboatrum sensu stricto, previously recovered from kiwifruit in New Zealand, were tested for pathogenicity against ‘Hort16A’ by artificial inoculation of young vines. Disease assessments were carried out monthly. Symptoms observed ranged from minor wilt to vine death. The V. alboatrum isolate appeared the most aggressive. Although there is evidence of some pathogenicity on kiwifruit within this group of isolates from Verticillium species in New Zealand, they appear less aggressive than those recorded in Chile. However, this cannot be confirmed without testing isolates from both countries concurrently under the same conditions.

During the 2017–18 growing season, significant outbreaks of leaf blight occurred in Pukekohe, Hawke’s Bay and Canterbury commercial onion fields. It was unknown if the causal agent was Stemphylium vesicarium, a pathogen already present in New Zealand that causes stemphylium leaf blight (SLB), or a new introduction of another Stemphylium species. Morphological and molecular characterisation methods were used to identify the pathogen present on diseased onion leaves. The possibility that climate may have been a contributor to the outbreak was evaluated using hourly temperature and relative humidity data, and comparing the 2017–18 growing season with the previous four seasons in these regions when no disease was observed. Our research indicates that the recent leaf blight outbreak in New Zealand was caused by S. vesicarium, and not the introduction of a novel species of Stemphylium. The warm, and wet summer of 2017–18 possibly contributed to the SLB outbreak.

The InterStim II (Medtronic, Inc., Minneapolis, MN) sacral nerve stimulator has been approved for MRI scanning of the head only, All other body areas are contraindicated by the manufacturer, This report presents the successful MRI examination of the left hand in a patient with an InterStim II device. Following an assessment of the risks and benefits of proceeding with the scan it was shown that there were minimal additional risks, which could be easily managed with appropriate patient positioning, coil selection and other established techniques. Informed consent was obtained and the scan completed without incident. Following the scan the patient reported full functioning of the device. MRI of the hand is feasible in patients with InterStim II implants using transmit/receive coils with appropriate risk controls in place. Further study of the safety of MRI of other body regions in InterStim II patients is appropriate.

ABSTRACT Tomato potato psyllid (TPP), Bactericera cockerelli (Sülc) (Hemiptera: Triozidae), is a vector for Candidatus Liberibacter solanacearum (Lso), a phloem-limited bacterium that causes severe production problems within the New Zealand potato industry. Field trials were conducted over three consecutive growing seasons between 2013 and 2016 at Pukekohe, New Zealand to determine the efficacy of an isoparaffinic petroleum distilled oil (JMS Stylet Oil®), applied as a foliar treatment within an insecticide programme, to control TPP. The effects of treatments on potato yield, tuber dry matter content and the incidence of zebra chip (ZC) in fried potato crisps were also assessed. This research demonstrated that JMS Stylet Oil, when used in combination with insecticides, achieved fewer insecticide applications, leading to reduced numbers of TPP nymphs and eggs on potato foliage, and lower incidence of ZC in deep-fried tuber crisps than weekly insecticide sprays, without adversely affecting plant growth and crop yields.

Fungicide resistance development in Botrytis cinerea threatens the efficacy of anilinopyrimidine (AP) fungicides, which have been used for botrytis bunch rot control in New Zealand vineyards for about 20 years. A 2016 survey of 33 vineyards in Gisborne, Hawke's Bay and Marlborough showed that the majority of 670 isolates tested in agar-based assays were sensitive to the AP cyprodinil (EC50 < 1 mg/litre), although 18% showed low-resistance (EC50 1-10 mg/litre) and 10% showed medium-resistance (EC50 >10 mg/litre). There was high cross-resistance to the APs cyprodinil and pyrimethanil. The survey also established baseline sensitivity to the succinate dehydrogenase inhibitor (SDHI) fungicide boscalid and >90% of isolates were sensitive (EC50 < 5 mg/litre). There was a low degree of cross-resistance between the SDHIs boscalid and fluopyram. There was also high sensitivity to fludioxonil (0.009 to 0.018 mg/litre) and to fenhexamid (0.49 to 0.76 mg/litre).

Isolates of Erysiphe necator from Hawkes Bay and Marlborough vineyards were tested for sensitivity to three demethylation inhibitor (DMI) fungicides (myclobutanil penconazole and cyproconazole) and one quinone outside inhibitor (QoI) fungicide (trifloxystrobin) Mean colony diameter was determined in a detached grape leaf assay for approximately 20 isolates per vineyard at 1 and 10 mg/litre of each fungicide Resistance to trifloxystrobin was prevalent in Hawkes Bay and Marlborough Mycobutanil resistance was found in both regions but particularly in Marlborough There was some loss of sensitivity to penconazole particularly in Marlborough Cyproconazole showed greater efficacy against E necator than the other two DMIs tested There was no explanation for the high trifloxystrobin resistance in sampled vineyards with few reports of trifloxystrobin use For DMIs there was a strong relationship between number of DMI fungicide applications over 10 years and DMI resistance across all three DMI active ingredients in both regions

A rotation trial spanning nine consecutive growing seasons was established in 2004 to study cumulative effects of specific onion- and potato-focused crop rotations on soil nutrient levels, soil biological communities, plant productivity and soilborne diseases. Soil microbial activity, as determined by fluorescein diacetate hydrolysis, was greatest in the sustainable' potato rotation in five of the 6 years that the test was carried out. Rhizoctonia solani anastomosis group 3 DNA was first detected in potato monoculture soils in the fifth year, with numbers increasing from then on, but was not detected in the onion monoculture throughout the trial period. Potato yields were greater when a crop other than potato was grown in the previous year compared with when potatoes were the preceding crop. After 2005, mean annual onion yields from the onion monoculture were less than yields from the other rotations. Black scurf on potato tubers was the primary soilborne disease observed during the study, and the incidence of this disease was greater in the potato monoculture than the other rotations after the second year, and least when potatoes had not been grown in the same ground the three previous seasons. This long-term crop rotation study has demonstrated the benefits of a sustainable' rotation where potatoes or onions were grown every fourth growing season, with different crops (oat, broccoli, cabbage, squash) grown in the intervening years, compared with the conventional consecutive biennial crops of potato and onion.

An 18-year-old patient was implanted with an MR-conditional pacemaker using a lead plug which negated the manufacturer CE approved MR conditional status of the pacing system. The patient was referred for a lumbar spine MRI. The clinical opinion was that the risk of proceeding with the MRI was acceptable given the alternatives of: (a) changing the pacing system or (b) not performing the scan. A risk assessment revealed that the additional risk was very low and easily mitigated by an established technique. Informed consent was obtained and the scan was completed without incident following a slightly modified MR-conditional pacemaker scanning protocol.

A major concern in potato and onion production worldwide is the sustainability of crop production systems using short-term rotations. Although rotation crops are known to influence soil microbial communities, few long-term field studies have investigated effects of potato and onion crop rotations on soil microflora and soilborne diseases. A long-term trial (10 years) was established in New Zealand in the 2004–05 season to determine changes in soil characteristics, soil biological communities, plant productivity and soilborne diseases resulting from different crop rotations. Six different crop rotation ‘treatments’ were used: three were onion-focused and three were potato-focused. For both the onion- and potato-focused rotations, one treatment was continual monoculture, one was biennial alternating onion and potato (‘conventional’ rotation, common local commercial practice) and one was a 4-year cycle where the onion or potato crops were grown every fourth season with different crops in the intervening seasons (‘sustainable’ rotation). The results of the rotations were evaluated at the end of 2012–13, nine growing seasons after the trial began. Soils from the three potato-focused rotations had similar microbial biomass carbon (C) and nitrogen (N), total C and N, and enzyme activity, but had different microbial activity parameters. Soils from the three onion rotations differed in organic matter content, total C and N, enzyme activity and carbohydrate utilization. The main factor correlated with potato diseases (stem canker, black scurf) and crop yields was the amount of Rhizoctonia inoculum in the soil. Onion yields in 2012–13 were correlated with the severity of pink root during the growing season. Total microbial activity in soil gave better relationships to soilborne disease incidence (Rhizoctonia stem canker of potato or pink root of onion) and to crop yields, than soil chemical parameters (pH, nutrient status, C:N ratio) or other microbiological parameters (microbial biomass, total culturable bacteria and fungi, and microbial diversity). This research has broadened understanding of effects of crop rotations on soil microbial community characteristics, soilborne diseases and crop productivity of potatoes and onions grown in a soil and an area where intensive vegetable production is common. This knowledge will assist growers to increase crop yields and reduce soilborne pathogens in a sustainable manner. Based on the results from this study, intensive potato and onion production should require these crops to be grown within 4-year crop rotations in order to foster sustainable yields and minimize soilborne diseases.