Selection of winter cereals for organic agriculture

Productivity in agriculture has more than tripled in developed countries since the 1950s. Beyond the success of plant breeding, the increased use of inorganic fertilizers, application of pesticides, and spread of irrigation also contributed to this success. However, impressive yield increases started to decline in the 1980s because of the lack of sustainability. One of the most beneficial ways to increase sustainability is organic agriculture. In such systems the prerequisite of successful farming is the availability of crop genotypes that perform well. However, selection of winter cereals for sub-optimal growing conditions is still neglected, and the organic seed market also lacks of information on credibly tested varieties suitable for organic agriculture

Performance and selection of winter durum wheat genotypes in different European conventional and organic fields

Sustainability is a key factor for the future of agriculture. Productivity in agriculture has more than tripled in developed countries since the 1950s. Beyond the success of plant breeding, the increased use of inorganic fertilizers, application of pesticides, and spread of irrigation also contributed to this success. However, impressive yield increases started to decline in the 1980s because of the lack of sustainability. One of the most beneficial ways to increase sustainability is organic agriculture. In such agro-ecosystem-based holistic production systems the prerequisite of successful farming is the availability of crop genotypes that perform well. However, selection of winter durum wheat for sub-optimal growing conditions is still mainly neglected, and the organic seed market also lacks of information on credibly tested winter durum varieties suitable for organic agriculture

A Metabolic Dependency for Host Isoprenoids in the Obligate Intracellular Pathogen Rickettsia parkeri Underlies a Sensitivity to the Statin Class of Host-Targeted Therapeutics.

Gram-negative bacteria in the order Rickettsiales have an obligate intracellular growth requirement, and some species cause human diseases such as typhus and spotted fever. The bacteria have evolved a dependence on essential nutrients and metabolites from the host cell as a consequence of extensive genome reduction. However, it remains largely unknown which nutrients they acquire and whether their metabolic dependency can be exploited therapeutically. Here, we describe a genetic rewiring of bacterial isoprenoid biosynthetic pathways in the Rickettsiales that has resulted from reductive genome evolution. Furthermore, we investigated whether the spotted fever group Rickettsia species Rickettsia parkeri scavenges isoprenoid precursors directly from the host. Using targeted mass spectrometry, we found that infection caused decreases in host isoprenoid products and concomitant increases in bacterial isoprenoid metabolites. Additionally, we report that treatment of infected cells with statins, which inhibit host isoprenoid synthesis, prohibited bacterial growth. We show that growth inhibition correlates with changes in bacterial size and shape that mimic those caused by antibiotics that inhibit peptidoglycan biosynthesis, suggesting that statins lead to an inhibition of cell wall synthesis. Altogether, our results describe a potential Achilles' heel of obligate intracellular pathogens that can potentially be exploited with host-targeted therapeutics that interfere with metabolic pathways required for bacterial growth.IMPORTANCE Obligate intracellular pathogens, which include viruses as well as certain bacteria and eukaryotes, are a subset of infectious microbes that are metabolically dependent on and unable to grow outside an infected host cell because they have lost or lack essential biosynthetic pathways. In this study, we describe a metabolic dependency of the bacterial pathogen Rickettsia parkeri on host isoprenoid molecules that are used in the biosynthesis of downstream products, including cholesterol, steroid hormones, and heme. Bacteria make products from isoprenoids, such as an essential lipid carrier for making the bacterial cell wall. We show that bacterial metabolic dependency can represent a potential Achilles' heel and that inhibiting host isoprenoid biosynthesis with the FDA-approved statin class of drugs inhibits bacterial growth by interfering with the integrity of the cell wall. This work supports the potential to treat infections by obligate intracellular pathogens through inhibition of host biosynthetic pathways that are susceptible to parasitism

Comparison of bread wheat varieties with different breeding origin under organic and low input management

The aims of the study were to compare 37 bread wheat varieties with different breeding origin under conventional and organic farming conditions in Hungary and Austria for three years and to identify traits highly sensitive to management systems that could be separated according to their suggested selecting environments. According to the results, heading date, sensitivity to leaf rust and powdery mildew had high heritability, thus, for economic reasons, it is reasonable to select for these traits in conventional fields even if the selection target is organic agriculture. On the contrary, selection for grain yield, test weight, leaf-inclination and vigorous growth should be done later in the target environment. It was concluded that the selecting environment has measurable effects on the performance of bread wheat varieties. Our results could help organic breeders in their selection work, especially in the continental climatic zone of Europe

FORMALDEHYDE RISK ASSESSMENT: PROPOSAL OF EXPOSURE LIMITS, CHARACTERISATION OF EXPOSURE, AND DEVELOPMENT OF SCENARIOS.

European Project INDEX-UPRIC 2009 In 2009, DG SANCO funded an update of the 2005 project INDEX \u201cCritical Appraisal of the Setting and Implementation of Indoor Exposure Limits in the EU\u201d. DG SANCO required a particular focus on formaldehyde, on the basis of new papers published following its re-classification in Group 1 (sufficient epidemiological and scientific evidence for an association with nasopharyngeal cancer) by IARC. INDEX-UPRIC 2009 (\u201cUPdate of PRIority Compounds\u201d) aimed at reviewing recent scientific data, but also at re-examining previous studies and re-considering the reference values proposed in 2005. From selected results of scientific literature and an innovative approach in applying uncertainty factors, making the best use of chemical specific data on toxicodynamics and toxicokinetics, new reference limits have been proposed for exposure to formaldehyde in indoor settings. The reference range of values for short-term exposure (30 minutes) proposed at EU level is 70-100 ppb (or 90-120 \ub5g/m3); it is comparable to most of exposure limits set by other national or international organisation. WHO in particular, in the latest version of IAQ guidelines (just published in December 2010), even if resulting from a different calculation, recommends a limit of 100 \ub5g/m3 (~80 ppb) for short-term exposure. The reference values proposed by INDEX UPRIC 2009 should be used for the risk characterisation of situations related to acute exposure to formaldehyde indoors. In the light of scientific data available, it can be considered protective from carcinogenic effects in relation to short-term exposure, although it is derived from an irritation endpoint. Always looking at the scientific evidence available so far, there is no indication of cumulative effects following exposure to low concentrations (below 1 ppm), as adverse effects seem to recover shortly after exposure period. Current knowledge allows to reasonably assume that the proposed reference range of concentrations is also protective from long-term health effects due to repetitive short-term exposures. However, attention must be paid at the outcomes of genotoxicity studies (currently inconclusive), particularly with concern to a potential association of formaldehyde with increased incidence of tumours other than those located in the site of exposure (airways tissues). Exposure characterisation and Exposure Scenarios in hospitals The hazard characterisation of formaldehyde carried out in INDEX UPRIC project indicates that recurrent, short-term, peak exposures, rather than exposure to constant levels, are expected to adversely affect eyes and upper airways in exposed subjects, posing also a potential risk for more severe health outcomes. Exposure to formaldehyde in occupational settings, and particularly in Pathology labs, appears to be characterised by concentration fluctuations and peaks. To perform a correct exposure assessment in Pathology Units, and to eventually associate exposure levels with health effects, an in-depth understanding of determinant factors of exposure and actual air levels, is a requirement. The project aimed to reach this goal through the development of detailed Exposure Scenarios and the characterisation of concentration fluctuations during specific tasks in Pathology Units of two different hospitals. Three monitoring methods have been adopted: passive, active and in-continuous techniques have been tested and their outcomes analysed. Potential hazards for operators\u2019 health have been identified during the performance of several tasks, being measured formaldehyde levels clearly above the TLV-C set by US ACGIH (0.3 ppm). From circumstances observed during monitoring, some misuses have been identified as well as inappropriateness of some organisational, logistic, and mitigation factors leading to high level of exposure (even above 1 ppm). Exposure Scenarios for critical tasks have been presented, including operational conditions, formaldehyde levels detected by the three techniques, possible causes of rises above the TLV-C, and proposed RMMs . Due to intrinsic properties of formaldehyde, its release from formalin solution is unavoidable, thus the implementation of RMMs is particularly crucial to avoid excessive exposure of operators. Much can be done in order to reduce critical situations, but measures to put into practice must be shared within all personnel working in the Unit. Less problematic alternatives (i.e. glutaraldehyde) should be also taken into account, considering the current debate on carcinogenicity and being formaldehyde in revision of classification at EU level as a consequence of a French request to place it among Carcinogens Category 1. Proposed RMMs have started to be put into place by Prevention and Protection Service of both hospitals. Very soon after their implementation another monitoring survey is foreseen, in order to check their effectiveness and appropriateness

The 2-Ga peraluminous magmatism of the Jacobina-Contendas Mirante belts (Bahia, Brazil) : geologic and isotopic constraints on the sources

L'étude pétrographique des intrusions granitiques du craton Sao Francisco (Bahia, Brésil) permet de définir la chronologie absolue des épisodes magmatiques et d'identifier les sources magmatiques ainsi que les processus géodynamiques se produisant lors de l'orogenèse transamazonienn

Investigating magnetic activity in very stable stellar magnetic fields: long-term photometric and spectroscopic study of the fully convective M4 dwarf V374 Peg

The ultrafast-rotating ($P_\mathrm{rot}\approx0.44 d$) fully convective single M4 dwarf V374 Peg is a well-known laboratory for studying intense stellar activity in a stable magnetic topology. As an observable proxy for the stellar magnetic field, we study the stability of the light curve, and thus the spot configuration. We also measure the occurrence rate of flares and coronal mass ejections (CMEs). We analyse spectroscopic observations, $BV(RI)_C$ photometry covering 5 years, and additional $R_C$ photometry that expands the temporal base over 16 years. The light curve suggests an almost rigid-body rotation, and a spot configuration that is stable over about 16 years, confirming the previous indications of a very stable magnetic field. We observed small changes on a nightly timescale, and frequent flaring, including a possible sympathetic flare. The strongest flares seem to be more concentrated around the phase where the light curve indicates a smaller active region. Spectral data suggest a complex CME with falling-back and re-ejected material, with a maximal projected velocity of $\approx$675km/s. We observed a CME rate much lower than expected from extrapolations of the solar flare-CME relation to active stars.Comment: 15 figures, 4 tables, accepted for publication in A&