An integrated strategy for the proactive management of grapevine trunk disease pathogen infections in grapevine nurseries

CITATION: Halleen, F. & Fourie, P. H. 2016. An integrated strategy for the proactive management of grapevine trunk disease pathogen infections in grapevine nurseries. South African Journal of Enology & Viticulture, 37(2):104-114, doi:10.21548/37-2-825.The original publication is available at http://www.journals.ac.za/index.php/sajevThe aim of this study was to compare 11 treatment regimes (TR) in grapevine nurseries in order to eradicate trunk pathogens. Grapevine propagation material was subjected to treatments before cold storage, before and after grafting, before planting and after uprooting. Isolations were made from roots, rootstocks and graft unions of uprooted vines. None of the treatments consistently affected the number of certifiable vines produced. TR 1 (benomyl), TR 3 (Sporekill) and TR 4 (Trichoflow) increased root mass. Phaeomoniella chlamydospora was the most frequently isolated pathogen from all plant parts. In general, TR 2, 7, 9 and 11 caused the lowest occurrence of Phaeomoniella. TR 9 consistently reduced the incidence of Phaeoacremonium. Pleurostomophora richardsiae occurred most frequently in graft unions, but treatments were too inconsistent to draw meaningful conclusions. TR 7 (hot water treatment (HWT) of uprooted grapevines) consistently reduced incidences of black foot disease (BFD) pathogens. The highest incidence of Botryosphaeriaceae occurred in graft unions, but all treatments significantly reduced infections. The colonisation of rootstocks and graft unions by Trichoderma was significantly better with TR 4 (Trichoflow). The other Trichoderma treatments (TR 9, 10 and 11) differed from the control treatment only in the graft unions. This is a first report of an integrated strategy covering all the phases of the propagation process, from the moment the nursery receives the propagation material until the dormant vines are removed. TR 9 is recommended for use in nurseries, although HWT of dormant vines is recommended to eradicate BFD pathogens. Benomyl can be replaced by carbendazim when benomyl is no longer available.http://www.journals.ac.za/index.php/sajev/article/view/825Publisher's versio

In vitro fertilisation when normal sperm morphology is less than fifteen per cent: Results of in vitro fertilisation and embryo transfer at H. F. Verwoerd Hospital, Pretoria

The outcome of in vitro fertilisation and embryo transfer in 90 couples where the husband's normal sperm morphology was less than 15% were analysed. Based on the percentage of morphologically normal spermatozoa the patients were divided into three groups: group A - normal morphological features 0 - 5%; group B - 6 - 10%; and group C - 11 - 14%. A control group had normal morphological features ≥ 15%. The fertilisation rate and number of embryos transferred was not significantly different in these groups. However, the pregnancy rate per embryo transfer was significantly different for groups A and B compared with group C and the control group (0% and 5,9% for groups A and B v. 13,9% and 18,3% for group C and the control group, respectively). It is concluded that when the normal sperm morphology is less than 11% the prospect of a pregnancy is poor

Endovascular treatment of intractable epistaxis - results of a 4-year local audit

Objective. Transcatheter embolisation is an accepted and effective treatment for intractable epistaxis. We analysed our success and complication rates and compared these with results from other published series.Design. Retrospective review.Setting. Unitas Interventional Unit, Centurion.Methods. Case record review (57 procedures) and telephonic interviews (36 traceable respondents).Outcome measures. A numerical audit of the success and complication rates for embolisation procedures performed during the 4-year period between July 1999 and June 2003.Results. A total of 57 endovascular embolisation procedures were performed for intractable epistaxis in 51 patients during this period. Eight patients (15.7%) developed a re-bleed between 1 and 33 days after embolisation of whom 5 were re- embolised, giving a primary short-term success rate of 86.3% and secondary assisted success rate of 94.1%. Thirty-five of 36 respondents {97.2%) reported no further epistaxis during the long-term follow-up period of 1-47months. The mortality rate was 0%, the major morbidity rate was 2% (l stroke) and the minor morbidity rate was 25%.Conclusion. Our Success and complication rates are acceptable and compare favourably with those reported in other large series

Awareness of Porcine Helminthiasis and the Prevalent Farm Management Operations Among Smallholder Pig Farmers in the Free State

Published ArticlePorcine helminthiasis and its zoonotic tendencies can lead to considerable loss of productivity and food security, especially in subsistence farming systems. Using open- and closed-ended questionnaires, this study was designed to ascertain the level of awareness of smallholder pig farmers in the selected districts of the Free State Province of South Africa to porcine helminthiasis and to gather information on the various pre- and post-slaughter practices prevalent in these areas. Results show that intestinal helminths emerged as the most common herd health problem (65.2%). There was a high rate of ignorance towards anthelmintic resistance and zoonoses among farmers. Similarly, 53.3% of respondents described the cost of anthelmintics as “expensive”. A high positive correlation (P<0.01) between some farming practices exist. Furthermore, 73.9% of respondents do not slaughter their pigs in an abattoir due to the high cost of slaughter and transportation, long distances to the abattoir, and small scale of production. Moreover, 50.0% of the farmers reported that their pig production enterprise was not profitable or viable. The information from this study may be used as baseline knowledge to help formulate the development of extension programmes for sustainable pig rearing and pork production, especially among smallholder farmers

Determination of the effective dose of a novel oral formulation of sarolaner (Simparica™) for the treatment and month-long control of fleas and ticks on dogs

AbstractThree laboratory studies were conducted to determine the appropriate dose of sarolaner, a novel isoxazoline, for the treatment and month-long control of infestations of fleas and ticks on dogs. In the first study, dogs were treated orally with sarolaner suspension formulations at 1.25, 2.5 or 5.0mg/kg, and infested with Dermacentor reticulatus, Rhipicephalus sanguineus ticks and with Ctenocephalides felis felis (cat flea) prior to treatment and then weekly for up to 8 weeks. Fleas and ticks were counted 48h after treatment and after each subsequent infestation at 24h for fleas and 48h for ticks. The lowest dose of sarolaner (1.25mg/kg) provided 100% efficacy against fleas from treatment through Day 35 and 98.4% at Day 56. This dose of sarolaner resulted in 99.7–100% control of both species of ticks through Day 28. In Study 2, dogs were dosed orally with placebo or sarolaner suspension formulations at 0.625, 1.25 or 2.5mg/kg and infested with Ixodes scapularis prior to treatment and weekly for 6 weeks, Amblyomma americanum (pretreatment and Day 26), Dermacentor variabilis (Day 33) and A. maculatum (Day 41). Ixodes scapularis was the most susceptible; the lowest dose (0.625mg/kg) providing>95% efficacy through Day 43. Efficacy against D. variabilis on Day 35 was>95% at 1.25 and 2.5mg/kg, whereas the 0.625mg/kg dose gave only 61.4% efficacy. Amblyomma spp. were the least susceptible ticks; efficacy of the 1.25mg/kg dose at Day 28 for A. americanum was markedly lower (88.5%) than achieved for D. reticulatus (100%) at Day 28 and also lower than for D. variabilis at Day 35 (96.2%). In Study 3, dogs were dosed orally with placebo or sarolaner in the proposed commercial tablet (Simparica™) at 1.0, 2.0 or 4.0mg/kg, and infested with A. maculatum, one of the ticks determined to be dose limiting, prior to treatment and then weekly for 5 weeks. All doses gave 100% control of the existing infestation. The two highest dosages resulted in >93% control of subsequent challenges for 5 weeks. There was no significant improvement in efficacy provided by the 4.0 mg/kg dose over the 2.0mg/kg dose (P>0.05) at any time point. The 2.0mg/kg dose was superior to the 1.0mg/kg on Day 14 (P=0.0086) and as efficacy for 1.0mg/kg declined below 90% at Day 28, a single 1mg/kg dose would not provide a full month of tick control. Thus, 2.0mg/kg was selected as the sarolaner dose rate to provide flea and tick control for at least one month following a single oral treatment

Cover crops with biofumigation properties for the suppression of plant-parasitic nematodes : a review

The original publication is available at http://www.sawislibrary.co.za/dbtw-wpd/textbase/sajev.htmPlant-parasitic nematodes are a problem in vineyards worldwide, with some species acting as vectors of grapevine soil-transmitted viruses. Global pressure on the use of soil-applied chemical nematicides has led to a search for new control options, or for alternative methods to suppress plant-parasitic nematodes as part of integrated pest management. This paper gives valuable background information on the use of cover crops with biofumigation properties for the suppression of plant-parasitic nematodes in vineyards.Winetech, Dried Fruit Technical Services and the National Research Foundation of South AfricaPublishers' Versio

Efficacy and safety of a novel oral isoxazoline, sarolaner (Simparica™), for the treatment of sarcoptic mange in dogs

AbstractThe efficacy of the novel isoxazoline, sarolaner (Simparica™) was investigated in dogs with clinical signs consistent with sarcoptic mange and harbouring natural infestations of Sarcoptes scabiei. One placebo-controlled laboratory study and one multi-centred field study with a commercial comparator containing imidacloprid/moxidectin (Advocate® spot-on) were conducted. Oral or topical treatments were administered on Days 0 and 30. Up to 10 skin scrapings were taken for the assessment of S. scabiei infestations from each dog before treatment and on Days 14, 30, 44 and 60 in the laboratory study, and on Days 30 and 60 in the field study. In the laboratory study, efficacy was calculated based on the percent reduction of mean live mite counts compared to the placebo group. In the field study parasitological cure rate (% dogs free of mites) was determined and non-inferiority of sarolaner to the control product was assessed.In the laboratory study 44 mixed breed dogs were enrolled in four batches. Due to decreasing mite counts in the placebo treated dogs, immunosuppression with dexamethasone (0.4mg/kg three times per week for two weeks) was initiated in all dogs on study at that time (n=6) and those subsequently enrolled (n=14). In the field study, dogs were enrolled in a 2:1 ratio (sarolaner:comparator); 79 dogs were assessed for efficacy and safety, and an additional 45 dogs were assessed for safety only. There were no treatment related adverse events in either study.In the laboratory study, no mites were found on any sarolaner-treated dogs 14 days after the first treatment except for one dog that had a single mite on Day 44. In the field study, the parasitological cure rate was 88.7% and 100% in the sarolaner group and 84.6% and 96.0% in the imidacloprid/moxidectin group, on Days 30 and 60, respectively. Statistical analysis showed that sarolaner was non-inferior to imidacloprid/moxidectin at both time points. The clinical signs of sarcoptic mange, including hair loss, papules, pruritus, erythema, and scaling/crusting improved throughout the study.Sarolaner was safe, achieved 100% reduction in the numbers of S. scabiei detected and resulted in marked improvement of the clinical signs of sarcoptic mange in dogs following two monthly oral administrations

Influence of water stress on Botryosphaeriaceae disease expression in grapevines

Several species in Botryosphaeriaceae have been associated with grapevine trunk diseases. To evaluate the effect of water stress on infection of grapevines by Botryosphaeriaceae spp., 1-year-old Shiraz/101-14 Mgt nursery grapevine plants were planted in plastic potting bags and placed outdoors under shade netting. Five weeks after planting, vines were pruned and the pruning wounds inoculated with spore suspensions of Neofusicoccum australe, Neofusicoccum parvum, Lasiodiplodia theobromae or Diplodia seriata. Control treatments consisted of applications of sterile water or a Trichoderma harzianum spore suspension. Stem inoculations were done by inserting a colonised or uncolonised agar plug into a wound made in each stem. Four different irrigation regimes were introduced 12 weeks after planting to simulate varying degrees of water stress. Measurements of stomatal conductance, photosynthetic rate and leaf spectrometry were made to monitor physiological stress. Eight months after inoculation, vines were uprooted and the root, shoot and plant mass of each vine determined. Lesions observed in the inoculated pruning wounds and stems were also measured. Vines subjected to the lowest irrigation regime were significantly smaller than optimally irrigated vines. Water stressed vines also had significantly lower photosynthetic rates and levels of stomatal conductance compared with vines receiving optimal irrigation, indicating that these plants experienced significantly higher levels of physiological stress. The mean lesion length was significantly longer in the pruning wounds and stems of plants subjected to the lowest irrigation regime, with lesion length declining linearly with increasing irrigation volume. These results clearly indicate that when a grapevine is exposed to water stress, colonisation and disease expression by Botryosphaeriaceae spp. are much more severe