Field testing and exploitation of genetically modified cassava with low-amylose or amylose-free starch in Indonesia

The development and testing in the field of genetically modified -so called- orphan crops like cassava in tropical countries is still in its infancy, despite the fact that cassava is not only used for food and feed but is also an important industrial crop. As traditional breeding of cassava is difficult (allodiploid, vegetatively propagated, outbreeding species) it is an ideal crop for improvement through genetic modification. We here report on the results of production and field testing of genetically modified low-amylose transformants of commercial cassava variety Adira4 in Indonesia. Twenty four transformants were produced and selected in the Netherlands based on phenotypic and molecular analyses. Nodal cuttings of these plants were sent to Indonesia where they were grown under biosafety conditions. After two screenhouse tests 15 transformants remained for a field trial. The tuberous root yield of 10 transformants was not significantly different from the control. Starch from transformants in which amylose was very low or absent showed all physical and rheological properties as expected from amylose-free cassava starch. The improved functionality of the starch was shown for an adipate acetate starch which was made into a tomato sauce. This is the first account of a field trial with transgenic cassava which shows that by using genetic modification it is possible to obtain low-amylose cassava plants with commercial potential with good root yield and starch quality

De staafmier Ponera coarctata in Nederland (Hymenoptera: Formicidae)

De staafmier staat bekend als zeldzaam, maar dat hangt samen met haar verborgen levenswijze. In deze bijdrage word eerst enkele opmerkelijke vindplaatsen van de staafmier uit het stedelijk gebied beschreven. De beschreven vondsten duiden erop dat de staafmier goed kan voorkomen in niet-natuurlijke situaties en mogelijk algemener is in het zuiden van Nederland dan nu wordt aangenomen. Daarnaast wordt informatie gegeven over haar voorkomen en ecologie op basis van collectiemateriaal en de literatuur. Ook wordt beschikbare informatie over de bruidsvluchten van deze soort mier gebundeld. Het uitvliegen van het nest blijkt plaats te vinden in de namiddag in de periode juli tot eind septembe

Biodiversity and pollination benefits trade off against profit in an intensive farming system

Agricultural expansion and intensification have boosted global food production but have come at the cost of environmental degradation and biodiversity loss. Biodiversity-friendly farming that boosts ecosystem services, such as pollination and natural pest control, is widely being advocated to maintain and improve agricultural productivity while safeguarding biodiversity. A vast body of evidence showing the agronomic benefits of enhanced ecosystem service delivery represent important incentives to adopt practices enhancing biodiversity. However, the costs of biodiversity-friendly management are rarely taken into account and may represent a major barrier impeding uptake by farmers. Whether and how biodiversity conservation, ecosystem service delivery, and farm profit can go hand in hand is unknown. Here, we quantify the ecological, agronomic, and net economic benefits of biodiversity-friendly farming in an intensive grassland–sunflower system in Southwest France. We found that reducing land-use intensity on agricultural grasslands drastically enhances flower availability and wild bee diversity, including rare species. Biodiversity-friendly management on grasslands furthermore resulted in an up to 17% higher revenue on neighboring sunflower fields through positive effects on pollination service delivery. However, the opportunity costs of reduced grassland forage yields consistently exceeded the economic benefits of enhanced sunflower pollination. Our results highlight that profitability is often a key constraint hampering adoption of biodiversity-based farming and uptake critically depends on society’s willingness to pay for associated delivery of public goods such as biodiversity

Kansen voor geleedpotigen in bermen : acht jaar onderzoek langs de weg

Geleedpotigen leven onder steeds moeilijker omstandigheden. De gebieden waar ze leven raken steeds verder versnipperd. Om die reden is het belangrijk om de overgebleven soorten beter te beschermen. Zo ontstond er ook hernieuwde belangstelling voor het leven van geleedpotigen in bermen. Bermen blijken een belangrijke ecologische waarde te hebben. Dit vraagt een doordachte aanpak van het maaien van berme

The Emergence and Early Evolution of Biological Carbon-Fixation

The fixation of into living matter sustains all life on Earth, and embeds the biosphere within geochemistry. The six known chemical pathways used by extant organisms for this function are recognized to have overlaps, but their evolution is incompletely understood. Here we reconstruct the complete early evolutionary history of biological carbon-fixation, relating all modern pathways to a single ancestral form. We find that innovations in carbon-fixation were the foundation for most major early divergences in the tree of life. These findings are based on a novel method that fully integrates metabolic and phylogenetic constraints. Comparing gene-profiles across the metabolic cores of deep-branching organisms and requiring that they are capable of synthesizing all their biomass components leads to the surprising conclusion that the most common form for deep-branching autotrophic carbon-fixation combines two disconnected sub-networks, each supplying carbon to distinct biomass components. One of these is a linear folate-based pathway of reduction previously only recognized as a fixation route in the complete Wood-Ljungdahl pathway, but which more generally may exclude the final step of synthesizing acetyl-CoA. Using metabolic constraints we then reconstruct a “phylometabolic” tree with a high degree of parsimony that traces the evolution of complete carbon-fixation pathways, and has a clear structure down to the root. This tree requires few instances of lateral gene transfer or convergence, and instead suggests a simple evolutionary dynamic in which all divergences have primary environmental causes. Energy optimization and oxygen toxicity are the two strongest forces of selection. The root of this tree combines the reductive citric acid cycle and the Wood-Ljungdahl pathway into a single connected network. This linked network lacks the selective optimization of modern fixation pathways but its redundancy leads to a more robust topology, making it more plausible than any modern pathway as a primitive universal ancestral form

Nascholing hoeft geen 'vaag theoretisch geleuter' te zijn

Contains fulltext : 24480___.PDF (publisher's version ) (Open Access

Arthropod richness in roadside verges in the Netherlands

Urbanisation and intensifi cation of agriculture has led to large scale destruction of natural and seminatural areas in Western Europe. Consequentially, the conservation of biodiversity in small landscape units has become a matter of increasing urgency. In this paper, we inventoried the arthropod diversity in roadside verges in the Netherlands and studied the relative importance of these linear elements. In addition, the occurrence of arthropods in roadside verges in other countries was studied by literature research. In the period 1998-2008, we sampled 57 roadside verges. Th is was mainly done by pitfall trapping, using sweeping nets and insect nets, and by sight observations. For several arthropod groups the majority of the Dutch indigenous species was sampled: ants (56% of the indigenous species), grasshoppers (53%), harvestmen (67%) and two spider families (52% and 68%). For ground beetles, weevils, butterfl ies, bees, hoverfl ies and three other spider families, values between 18-41% were found. Considering that only a minute fraction of the vast network of roadsides was sampled, these fi gures are remarkably high. Roadside verges are occasionally reported to act as dispersal corridors for exotic species, but this could not be confi rmed for arthropods in the Netherlands. Several of the arthropod species inventoried in the Dutch verges are classifi ed as threatened: fi ve grasshopper and eleven bee species appear on national Red Lists and six ant species on the IUCN Red List. Also, in several other countries roadside verges in intensively used landscapes appear to off er opportunities for arthropod conservation. We conclude that, if rightly managed, roadside verges can serve as an important and valuable arthropod habitat. Th erefore, we strongly recommend taking always into account the conservation of these arthropod assemblages during planning and actual management of roadside verge