Economic and agronomic feasibility of organic vegetable seed production in the UK, and subsequent seed quality (OF0166)

This is the final report of Defra project OF0166. There is a longer summary at the start of the attached main report. For many farmers and growers, a move to organic production presents major challenges. Among these, the issues regarding the use of organic seeds could yet be a stumbling block, as growers and the seed trade have reservations about using and producing them for four major reasons: 1) The availability of a wide range of organic varieties appropriate to all year round crop scheduling, and differing production techniques and markets 2) The impact of derogation on managing the supply and demand for organic seed 3) The technical issues of organic seed production 4) Maintaining high standards of seed quality, hygiene and vigour. Three biennial vegetable crops: parsnips, winter cauliflower, and bulb onions and a small range of annual crops including lettuces, runner beans, spinach, broccoli were grown for seed production. All the crops were grown under a Spanish “Haygrove” tunnel. These relatively cheap structures allow good ventilation whilst offering protection against wet weather. All the crops were grown following organic protocols. Seed yields were recorded, and comparisons with disease contamination, germination and vigour were made against seed of the same variety produced conventionally by the collaborating seed company. Yields were unpredictable for some crops in the early stages of the project, but this problem was overcome as techniques were better understood and more experience gained. Seed quality was generally very good for most crops, and few problems were encountered with seed borne diseases for most crops. High levels of seed surface contamination with saprophytic fungi (Penicillium and Cladosporium) may have masked the presence of other fungi. Where equivalent comparisons with conventional seedlots could be tested for disease and vigour differences were small. However, major problems were encountered with bulb onion seed production as neck rot resulted in loss of stock material (around 50% of bulbs were lost). Hot water treatments were used in this project and were found to be successful against a range of pathogens on infected onion seed. More research into organic seed treating is advocated. The project has shown that on a small scale at least, good quality organic seed can be produced under relatively inexpensive polythene tunnels. The yields attained can be as good as those from conventional production, but there are without doubt greater risks involved. It is suggested that should diseases or pests become rampant then their control will be difficult. This project has shown that crops like onions are extremely difficult to produce, and that neck rot in particular will be a problem for the seed producer and grower. The use of tunnels is strongly supported; they can keep crops dry at harvest, they do not necessarily encourage disease build up and natural predator populations can be built up in and around them. It can be summed up that 1) Organic seed production was found to feasible, but higher risk than conventional production 2) Seed quality differences were small 3) Costs in terms of management input were high 4) Neck rot ( Botrytis allii) on bulb onions was, and is likely to remain, a persistent problem 5) Hot water treatment was found to be satisfactory for the small volumes of seed treated. Urgent attention is needed to identify other more consistent methods than this which will satisfy Organic protocols

Nevirapine toxicity- implications for management of South African patients

No Abstract

Acute dichromate poisoning following the use of toxic purgatives

During the last ten years, several patients have presented to the Renal Unit of Groote Schuur Hospital with acute renal failure following the use of traditional (N'anga or Gqirha) medication. The history together with abnormal liver-function tests and renal failure was thought to be suggestive of a toxic aetiology. The specific toxin however remained unknown, until during the admission of one patient, a relative brought in the medication, analysis of which revealed a high concentration of potassium dichromate. Subsequently elevated levels of chromium were demonstrated by atomic absorption spectrometry in the blood and urine of this patient. Following this case there have been six further cases of acute renal failure resulting from use of dichromate containing traditional remedies. These remedies were obtained from a variety of sources including street-hawkers, herbal chemists, and traditional healers. Clinical and laboratory data relating to these seven patients will be presented

From despair to hope studies in HIV and tuberculosis 1992-2011

Includes abstract. Includes bibliographical references

Acute dichromate poisoning following the use of toxic purgatives

During the last ten years, several patients have presented to the Renal Unit of Groote Schuur Hospital with acute renal failure following the use of traditional (N'anga or Gqirha) medication. The history together with abnormal liver-function tests and renal failure was thought to be suggestive of a toxic aetiology. The specific toxin however remained unknown, until during the admission of one patient, a relative brought in the medication, analysis of which revealed a high concentration of potassium dichromate. Subsequently elevated levels of chromium were demonstrated by atomic absorption spectrometry in the blood and urine of this patient. Following this case there have been six further cases of acute renal failure resulting from use of dichromate containing traditional remedies. These remedies were obtained from a variety of sources including street-hawkers, herbal chemists, and traditional healers. Clinical and laboratory data relating to these seven patients will be presented

Nevirapine toxicity - implications for management of South African patients

Nevirapine was the first non-nucleoside drug (NNRTI) to be approved by the Federal Drug Administration (FDA) for use in combination therapy of HIV-1 infection in 1996. It has been approved for use in children of 2 months or older, and following the publication of the HIVNET 012 study in Uganda1 has been widely used as single-dose prophylaxis for prevention of mother-to-child HIV transmission (MTCT) in resource-poor settings. Early in nevirapine development, a cutaneous hypersensitivity rash occurring in the first 4 weeks of therapy was recognised as a common side-effect, and registration studies reported clinical hepatitis in approximately 1% of individuals.2 Despite these recognised toxicities, cheap generic formulations, including fixed-dose combinations, have been manufactured in India and Brazil, making nevirapine one of the most commonly prescribed antiretrovirals worldwide

Following the Sun: The pioneering years of solar energy research at The Australian National University 1970—2005

In 1970 a small group of physicists at The Australian National University decided to veer away from the accepted and expected directions in energy research and pursued the emerging discipline of solar energy. Over the next decade ANU joined a small cluster of research institutions, including the CSIRO, UNSW and the University of Sydney, to emerge as a world leader in solar energy technology. This book traces the history of solar energy research at ANU over 35 years from its origin, its sometimes controversial early stages, through its flagship projects to its current status as one of the world’s best known solar energy research establishments. It is as much a story of the future as it is a history: Following the sun is the story of how an idea to pursue what was in 1970 a new and unpopular research path has come to underpin sustainable development in the 21st Century

Antiretroviral treatment as prevention: impact of the 'test and treat' strategy on the tuberculosis epidemic.

Antiretroviral therapy (ART) has been remarkably effective in ameliorating Human Immunodeficiency Virus (HIV)-associated morbidity and mortality. The rapid decline in viral load during ART also presents an opportunity to develop a "treatment as prevention" strategy in order to reduce HIV transmission at a population level. Modelling exercises have demonstrated that for this strategy to be effective, early initiation of ART with high coverage of the HIV-infected population will be required. The HIV epidemic has fueled a resurgence of tuberculosis (TB) particularly in sub- Saharan Africa and widespread early initiation of ART could also impact this epidemic via several mechanisms. The proportion of patients with low CD4 cell counts who are at high risk of TB disease from progression of both latent and new TB infection would be greatly reduced. Entry into a life-long ART program provides an ongoing opportunity for intensified TB case finding among the HIV-infected population. Regular screening for HIV infection also presents an opportunity for intensified TB case finding in the general population. The combined effect of reduced progression of infection to disease and intensified case finding could reduce the overall prevalence of infectious TB, thereby further decreasing TB transmission. In addition, decreasing prevalence of HIV infection would reduce the TB-susceptible pool within the population. The 'test and treat' strategy therefore has potential to reduce the TB risk at both an individual and a population level. In this paper we explore the expected "TB dividend" of wider access to ART and also explore the potential of the "test and treat" strategy to impact on TB transmission, particularly in the heavily burdened setting of sub- Saharan Africa

Isoniazid preventive therapy for tuberculosis in South Africa: An assessment of the local evidence base

Worldwide, South Africa (SA) has the worst tuberculosis (TB) epidemic. In SA, there are > 6.1 million people living with HIV (PLWH) and the country now has the largest antiretroviral treatment programme with > 2 million people receiving combination therapy. While there has been a marked recent decline in HIV-associated deaths, > 50% of TB cases still continue to be diagnosed in PWLH. The current TB control strategy based on passive case finding, chemotherapy of childhood TB contacts and directly observed therapy has clearly failed to control endemic TB in SA. Two recent meta-analyses have shown a > 60% reduction in TB in HIV-infected adults after isoniazid preventive therapy (IPT). SA has implemented the World Health Organization policy and IPT is now recommended for HIV-positive people for up to 36 months. Originally, there was only one SA study included in the evidence base supporting this policy, but subsequently four randomised controlled trials have been conducted in SA populations. These studies, together with local observational studies, are the subject of this local, evidence-based review