Cover Crop Management in Vineyards of the Lower Orange River Region, South Africa: 2. Effect on Plant Parasitic Nematodes

This study was conducted as part of a larger investigation into the effect of management practices on selected sowncover crops and the effects thereof on grapevine performance. The aim of this study was to determine the effect of thesecover crops on plant parasitic nematode populations under natural field conditions. The trial site was in an own-rootedSultanina vineyard situated in the Lower Orange River of the Northern Cape Province. Three management practiceswere applied selectively to ten cover crop species, with two control treatments consisting of weeds. Nematodes weremonitored for a period of four years. ‘Saia’ oats were indicated as being poor hosts to both root-knot and root-lesionnematodes, while ‘Overberg’ oats showed poor host status against ring nematodes. ‘Midmar’ ryegrass and ‘Paraggio’medic were also poor hosts for root-knot nematodes, while grazing vetch appeared to be a good host for root-knotnematodes. The most notable result from this study was the relatively high numbers of all three nematodes on the vinerow, as opposed to the inter-row where cover crops were established. This indicates that vines were much better hostsfor these nematodes than the cover crops. It is recommended that if more definite trends are to be observed, Brassicaspecies, which have direct toxic/repellant effects on nematodes, should be tested

PROMOTING PROFITABILITY AND SUSTAINABILITY IN THE BACKGROUNDING OF BEEF CALVES: THE ROLE OF AGRICULTURAL EXTENSION.

Published ArticleThere are indications that the backgrounding of beef calves will become more important in future as heavier beef carcasses are required. To increase the profitability of beef systems, backgrounding prepare weaned calves for finishing on high energy rations to promote rapid weight gain in a feedlot. Backgrounding operations may be pasture or dry-lot based or some combination thereof. The primary objective of this study was to investigate factors leading to poor average daily gain (ADG), high morbidity and mortality rate and the increased costs of gain. The secondary objective was to study the management practices followed in the backgrounding of beef calves concerning purchasing, adaptation, processing, raising, health management and marketing strategies. Forty questionnaires were administered to farmers, small and large feedlots doing backgrounding of beef calves. Data was generated by using the SUM equation and the means, minimum and maximum were generated by using PROC MEANS in SAS (2004). On-farm observations were employed in collecting data and discussions with other farmers and experts doing backgrounding of beef calves. According to this study, the ADG for summer differed significantly (P<0.05) from that of winter as the ADG during summer was 22.2% higher than that of winter. However, the study also showed that the feed intake in summer differed significantly (P<0.05) from that of winter with summer feed intake being 13% higher than winter feed intake. The production costs per calf in this study were R300.50±158.60 for feeding costs, R138.10±90.80 for remedies, R56.40±22.10 for processing and R37.50±24.30 for transport costs. It was also evident that parainflueza 3 known as flu was the infectious disease that mostly led to morbidity and mortality. With protozoal diseases, gall-sickness and red-water was the major cause of mortality. Mortality as a result of nutritional disorder including bloat and acidosis was reported by 37.5% of the respondents. The paper stresses the role of agricultural extension in the optimization of backgrounding systems

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

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

Improving Management Practices of Emerging Cattle Farmers in Selected Areas of the Eastern Cape Province: The Role of Agricultural Extension

Published ArticleThe study was conducted to determine cattle production and management practices of developing cattle farmers in two selected districts (Amathole and Chris Hani) in the Eastern Cape Province of South Africa. The study mainly focused on beef cattle farmers that are farming on leased or private land. From both districts, 60 respondents (30 per district) were interviewed using structured questionnaires. Results showed that 33% of the study sample had low levels of education while only 15% (n=10) had tertiary education qualifications. Cattle management activities were performed by almost all the respondents except deworming which was done by only 33%. The respondents were mostly vaccinating for diseases such as Black quarter (42%), Redwater (40%), and Anthrax (30%). The assessed farmers were controlling parasites with many different methods, however, pour on was found to be the most frequently used method (52%), followed by plunge dipping (33%) and hand spray (32%). There were farmers that planted cultivated pastures (35%) and some that were also using supplements (licks) for their herds (77%). As bush encroachments were not a problem in some farms, most farmers were not taking any actions, but 24% were using fires when reducing moribund. Breeding monitoring activities (birth observation, pregnant test and bull futility testing) were conducted by the respondents (78%, 15% and 12% respectively). It is recommended that agricultural extension play an imperative role in linking possible role players and farmers

A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa

Riparian habitats in many parts of South Africa are severely degraded by invasive alien plants, especially trees. These invasions reduce water yields from catchments and affect riverine functioning and biodiversity. Initiatives are under way countrywide to clear alien plants from watercourses and surrounding catchments. Current understanding of key processes that regulate riparian functioning and define options for restoration is rudimentary. We review the impacts of riparian invasions and identify factors limiting the recovery of natural vegetation following alien clearance. We propose a framework of strategic interventions for optimizing restoration success. The framework identifies abiotic and biotic barriers to restoration at the scales of catchments and local reaches. In highly transformed catchments, interventions at the reach scale may fail if important barriers at the catchment scale are not addressed. The extent to which propagule supply and microsite conditions inhibit vegetation recovery is unknown. We also know little of the relative importance of dispersing vegetative propagules, dispersing seeds and soil-stored seed banks in vegetation dynamics, particularly after severe disturbances such as dense invasion by alien plants. The importance of geomorphological and hydrological factors in mediating recovery of riparian vegetation has not been adequately explored for all climatic areas in South Africa. More research is needed to determine the influence of different alien species and clearing treatments on the recovery of riparian vegetation. The literature strongly suggests that in highly alien-transformed catchments, the re-introduction of riparian species is required to promote recovery and suppress re-invasion. However, such interventions are unlikely to be widely implemented unless the cost: benefit ratios are favourable

A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa

The original publication is available at http://www.sabinet.co.za/?page=open-access-journalsRiparian habitats in many parts of South Africa are severely degraded by invasive alien plants, especially trees. These invasions reduce water yields from catchments and affect riverine functioning and biodiversity. Initiatives are under way countrywide to clear alien plants from watercourses and surrounding catchments. Current understanding of key processes that regulate riparian functioning and define options for restoration is rudimentary. We review the impacts of riparian invasions and identify factors limiting the recovery of natural vegetation following alien clearance. We propose a framework of strategic interventions for optimizing restoration success. The framework identifies abiotic and biotic barriers to restoration at the scales of catchments and local reaches. In highly transformed catchments, interventions at the reach scale may fail if important barriers at the catchment scale are not addressed. The extent to which propagule supply and microsite conditions inhibit vegetation recovery is unknown. We also know little of the relative importance of dispersing vegetative propagules, dispersing seeds and soil-stored seed banks in vegetation dynamics, particularly after severe disturbances such as dense invasion by alien plants. The importance of geomorphological and hydrological factors in mediating recovery of riparian vegetation has not been adequately explored for all climatic areas in South Africa. More research is needed to determine the influence of different alien species and clearing treatments on the recovery of riparian vegetation. The literature strongly suggests that in highly alien-transformed catchments, the re-introduction of riparian species is required to promote recovery and suppress re-invasion. However, such interventions are unlikely to be widely implemented unless the cost:benefit ratios are favourable.Publishers' Versio

A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa

Riparian habitats in many parts of South Africa are severely degraded by invasive alien plants, especially trees. These invasions reduce water yields from catchments and affect riverine functioning and biodiversity. Initiatives are under way countrywide to clear alien plants from watercourses and surrounding catchments. Current understanding of key processes that regulate riparian functioning and define options for restoration is rudimentary. We review the impacts of riparian invasions and identify factors limiting the recovery of natural vegetation following alien clearance. We propose a framework of strategic interventions for optimizing restoration success. The framework identifies abiotic and biotic barriers to restoration at the scales of catchments and local reaches. In highly transformed catchments, interventions at the reach scale may fail if important barriers at the catchment scale are not addressed. The extent to which propagule supply and microsite conditions inhibit vegetation recovery is unknown. We also know little of the relative importance of dispersing vegetative propagules, dispersing seeds and soil-stored seed banks in vegetation dynamics, particularly after severe disturbances such as dense invasion by alien plants. The importance of geomorphological and hydrological factors in mediating recovery of riparian vegetation has not been adequately explored for all climatic areas in South Africa. More research is needed to determine the influence of different alien species and clearing treatments on the recovery of riparian vegetation. The literature strongly suggests that in highly alien-transformed catchments, the re-introduction of riparian species is required to promote recovery and suppress re-invasion. However, such interventions are unlikely to be widely implemented unless the cost: benefit ratios are favourable

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