Recasting Economics as if the Climate and Global Ecology Really Mattered

Peer reviewedPublisher PD

Effect of sorghum seed treatment in Burkina Faso varies with baseline crop performance and geographical location

Sorghum [Sorghum bicolor (L.) Moench] is a major subsistence crop throughout the region of Sahel. With the exception of seeds and labour, no agricultural inputs are in general used in sorghum production since the grain is of a relatively low commercial value and the risk of losing the crop to drought, flooding, etc. is substantial. A meta-analysis of 118 field experiments was carried out to identify conditions in which two protective seed treatments could support a yield increase of sorghum in Burkina Faso. The two treatments were: i) treatment with the pesticide Calthio C (thiram and chlorpyrifos) and ii) treatment with an aqueous extract from the plant clipta alba. Both treatments were found to produce a yield increase (Medians: Calthio C +199 kg ha-1, P<2x10-9; E. alba +90.5 kg ha-1 P<4x10-4). A strong relative effect of Calthio C on yield (+36%) was found for field experiments with a low baseline yield. A strong relative effect of E. alba extract on yield (+22%) was found for experiments with a low baseline of emergence. ANOVA of the 118 field tests showed that baseline crop performance (yield and emergence) and the effect of seed treatments were strongly linked to geographical location (twelve different villages included). Roots from sorghum in the village showing the strongest effect of both seed treatments (>40% yield increase) were found to carry a comparatively high load of the infectious ascomycetes: Fusarium equiseti, Macrophomina phaseolina and Curvularia lunata.Key Words: Curvularia lunata, Fusarium equiseti, Macrophomina phaseolina, Sorghum bicolo

Recasting Economics As If the Climate and Global Ecology Really Mattered

The current paradigm of global economics with exponential and continuous economic growth is unsustainable as far as Earth system ecology is concerned. To support the Earth system and boost sustainable development, a functional and operational linkage between global ecology and economics should be established – which we term ‘carbonomics’. The simple basis of ‘carbonomics’ is that the more fossil and non-fossil carbon one has as stocks, and not flows, of carbon, the richer one is. This opinion piece makes some suggestions about how we might establish such a balanced relationship

Recasting Economics As If the Climate and Global Ecology Really Mattered

The current paradigm of global economics with exponential and continuous economic growth is unsustainable as far as Earth system ecology is concerned. To support the Earth system and boost sustainable development, a functional and operational linkage between global ecology and economics should be established – which we term ‘carbonomics’. The simple basis of ‘carbonomics’ is that the more fossil and non-fossil carbon one has as stocks, and not flows, of carbon, the richer one is. This opinion piece makes some suggestions about how we might establish such a balanced relationship

Root distribution in intercropping systems – a comparison of DNA based methods and visual distinction of roots

This study was performed to i) compare root distribution of legume/non-legume intercrops determined by qPCR and amplicon sequencing (Meta-barcoding) to root growth of the individual species determined visually, and ii) compare the qPCR and amplicon sequencing techniques as a method for quantifying root growth of individual species grown in mixtures. Red beet (Beta vulgaris L. cv Detroit) and lucerne (Medicago sativa L. cv Creno) were grown in one-meter-high transparent tubes. Root competition was studied by direct observation on the tube surface determining root intensity (RI), root wash and extraction followed by determination of root length density (RLD), and DNA-based methods. Intercropping decreased lucerne RI strongly, whereas the RI of red beet was not affected. The determination of RLD did not allow us to distinguish species in mixed samples. However, both DNA methods showed apparently a tendency to overestimate the fraction of lucerne roots compared to the direct root observations. The discrepancy between methods was explained by the fact that visual methods provide estimates of root length while the DNA methods provide estimates of root mass. In conclusion, DNA-based estimates of species fractions in mixed root samples give valuable information on root interactions in mixed crops

Golgi Localized Barley <i>MTP8</i> Proteins Facilitate Mn Transport

<div><p>Many metabolic processes in plants are regulated by manganese (Mn) but limited information is available on the molecular mechanisms controlling cellular Mn homeostasis. In this study, a yeast assay was used to isolate and characterize two genes, <i>MTP8.1</i> and <i>MTP8.2</i>, which encode membrane-bound proteins belonging to the cation diffusion facilitator (CDF) family in the cereal species barley (<i>Hordeum vulgare</i>). Transient expression in onion epidermal cells showed that MTP8.1 and MTP8.2 proteins fused to the green fluorescent protein (GFP) are localized to Golgi. When heterologously expressed in yeast, MTP8.1 and MTP8.2 were found to be Mn transporters catalysing Mn efflux in a similar manner as the Golgi localized endogenous yeast protein Pmr1p. The level of <i>MTP8.1</i> transcripts in barley roots increased with external Mn supply ranging from deficiency to toxicity, while <i>MTP8.2</i> transcripts decreased under the same conditions, indicating non-overlapping functions for the two genes. In barley leaves, the expression of both <i>MTP8</i> genes declined in response to toxic Mn additions to the roots suggesting a role in ensuring proper delivery of Mn to Golgi. Based on the above we suggest that barley MTP8 proteins are involved in Mn loading to the Golgi apparatus and play a role in Mn homeostasis by delivering Mn to Mn-dependent enzymes and/or by facilitating Mn efflux via secretory vesicles. This study highlights the importance of MTP transporters in Mn homeostasis and is the first report of Golgi localized Mn²⁺ transport proteins in a monocot plant species.</p></div