A temporal assessment of nematode community structure and diversity in the rhizosphere of cisgenic Phytophthora infestans-resistant potatoes

This is publication No. 18 produced within the framework of the project Assessing and Monitoring the Impacts of Genetically Modified Plants on Agro-ecosystems (AMIGA), funded by the European Commission in the Framework programme 7. THEME [KBBE.2011.3.5-01].peer-reviewedBackground Nematodes play a key role in soil processes with alterations in the nematode community structure having the potential to considerably influence ecosystem functioning. As a result fluctuations in nematode diversity and/or community structure can be gauged as a ‘barometer’ of a soil’s functional biodiversity. However, a deficit exists in regards to baseline knowledge and on the impact of specific GM crops on soil nematode populations and in particular in regard to the impact of GM potatoes on the diversity of nematode populations in the rhizosphere. The goal of this project was to begin to address this knowledge gap in regards to a GM potato line, cisgenically engineered for resistance to Phytophthora infestans (responsible organism of the Irish potato famine causing late blight disease). For this, a 3 year (2013, 2014, 2015) field experimental study was completed, containing two conventional genotypes (cvs. Desiree and Sarpo Mira) and a cisgenic genotype (cv. Desiree + Rpi-vnt1). Each potato genotype was treated with different disease management strategies (weekly chemical applications and corresponding no spray control). Hence affording the opportunity to investigate the temporal impact of potato genotype, disease management strategy (and their interaction) on the potato rhizosphere nematode community. Results Nematode structure and diversity were measured through established indices, accounts and taxonomy with factors recording a significant effect limited to the climatic conditions across the three seasons of the study and chemical applications associated with the selected disease management strategy. Based on the metrics studied, the cultivation of the cisgenic potato genotype exerted no significant effect (P > 0.05) on nematode community diversity or structure. The disease management treatments led to a reduction of specific trophic groups (e.g. Predacious c–p = 4), which of interest appeared to be counteracted by a potato genotype with vigorous growth phenotype e.g. cv. Sarpo Mira. The fluctuating climates led to disparate conditions, with enrichment conditions (bacterial feeding c–p = 1) dominating during the wet seasons of 2014 and 2015 versus the dry season of 2013 which induced an environmental stress (functional guild c–p = 2) on nematode communities. Conclusions Overall the functional guild indices in comparison to other indices or absolutes values, delivered the most accurate quantitative measurement with which to determine the occurrence of a specific disturbance relative to the cultivation of the studied cisgenic P. infestans-resistant potatoes.European Unio

The political role of national oil companies in exporting countries : the Venezuelan case

The philosophy of modern, capitalist economies favours the pursuit or maximization of profit and frowns upon rent and rent seekers. The international oil companies investing in oil-exporting countries of the Third World naturally shared this philosophy. They were faced, however, with landlord states most concerned with the maximization of ground-rent. Ultimately, nationalization was used by most of these states to achieve this goal. The national oil company came thus into existence as a rent collector for the landlord states. Yet its own interest, as in the case of international petroleum corporations, lies in the maximization of profit which calls for the minimization of the share of income taken in rent. There are tensions, therefore, between the demands of their owner - that is the landlord state - and their corporate motivations and goals. The central question raised by this paper is whether the national oil companies are able to develop new types of landlord tenant relationships that can cope with these tensions. To investigate this issue the author studies the national oil company of an important oil-exporting country - Venezuela. He assesses the difficulties encountered by Petroleos de Venezuela (PDV) in creating the necessary legal and institutional framework for operating as a truly commercial enterprise. One of the difficulties is the absence of a clear criterion for distinguishing the company profits from the rent element of its total revenues, and therefore for establishing the correct fiscal base. The study also refers to PDV’s position and role in the three joint ventures with foreign companies, already approved by the Venezuelan Congress. The assessment is that PDV did not succeed in establishing a clear definition of its position in these relationships with foreign investors. The author’s main thesis is that the central role of national oil companies is to create a viable modus vivendi between the state, acting as a rent maximising landlord, and the company itself, operating as a new commercial enterprise. He believes that this may be facilitated by an alliance with an actor which has been so far excluded from the scene, namely national private capital. </p

The governance of international oil : the changing rules of the game

Most people still believe that the big international oil Companies dominate the governance of world oil. This is not surprising since these companies continue to be amongst the largest in the world and through most of the twentieth century their power has been unchallenged. Their eclipse inside the exporting countries by the national oil companies has been only partial since they have not lost their supremacy in the development and application of new technologies; and outside the exporting countries they have ceded none of their powers. In short, it is clear that the international oil companies are not preparing to retire from the stage they have dominated for so long

Fiscal regimes and oil revenues in the UK, Alaska and Venezuela: OIES paper: M27

In this paper we shall discuss the performance of three oil fiscal regimes over the past 25 years: the UK, Alaska, and Venezuela. This empirically oriented paper is based on our previous more theoretical paper on the subject of oil fiscal regimes, but it can be read independently. Nevertheless, a reminder of a few points made in that paper may be helpful

The new governance of Venezuelan oil

Since 1989 Venezuela has been developing a new oil policy, known as Politica Petrolera de Apertura (Oil Opening Policy), or Apertura Petrolera for short. With Apertura Petrolera the Venezuelan oil sector, nationalised in 1976, has been re-opened to private investors. Inviting private investors back may itself be considered a historic voIte-face in Venezuelan oil politics, though the government and the national oil company, Petróleos de Venezuela (PDV),l argued that this contingency was anticipated in the Nationalisation Law. But a few years later the leadership of the national oil company was self-confident enough to admit that the ultimate goal was the privatisation of PDV. Hence Apertura Petrolera involves, without doubt, a major policy shift in the history of Venezuelan oil

Private landlord-tenant relationship in British coal and American oil : a theory of mineral leases: OIES paper: EE20

A very great and, at first glance, confusing variety of tenancy arrangements for mineral resources can be observed around the world. Substance and form may vary not only from one country to another, but even from one region to another within the same country. In addition, the type of tenancy may vary from one mineral to another, largely determined by an accident of history, possibly a history going back to ancient times. One basic and obvious distinction to be made, however, is between public and private ownership. Public ownership of mineral resources is the rule worldwide, private ownership the exception. Yet by far the most important examples of extractive industries in modern economic history, British coal and American oil, both developed under private mineral property although it was brought to an end, in the former case, by nationalization in 1938. This paper will deal with these two exceptions which will, incidentally, confirm the rule

Private landlord-tenant relationship in British coal and American oil : a theory of mineral leases

A very great and, at first glance, confusing variety of tenancy arrangements for mineral resources can be observed around the world. Substance and form may vary not only from one country to another, but even from one region to another within the same country. In addition, the type of tenancy may vary from one mineral to another, largely determined by an accident of history, possibly a history going back to ancient times. One basic and obvious distinction to be made, however, is between public and private ownership. Public ownership of mineral resources is the rule worldwide, private ownership the exception. Yet by far the most important examples of extractive industries in modern economic history, British coal and American oil, both developed under private mineral property although it was brought to an end, in the former case, by nationalization in 1938. This paper will deal with these two exceptions which will, incidentally, confirm the rule