Building Supportive Networks Among Agricultural Innovators Through a Symposium on Dryland Organic Farming

Extension can play a valuable role by bringing together those who are pioneering innovative practices. We planned, built, and evaluated an Extension symposium on dryland organic agriculture. Post-symposium evaluations indicated that this process disseminated regionally relevant information; fostered networks among producers, researchers, and the organic processing and feed industries; enhanced trust among stakeholders; and increased interest in expanding organic production. Ninety-five percent of respondents indicated that they established new business relationships within 6 months of the symposium. A unique aspect of our project was the enhancement of social capital between geographically separated rural localities

Bacteria and Competing Herbivores Weaken Top–Down and Bottom–Up Aphid Suppression

Herbivore suppression is mediated by both plant defenses and predators. In turn, plant defenses are impacted by soil fertility and interactions with soil bacteria. Measuring the relative importance of nutritional and microbial drivers of herbivore resistance has proven problematic, in part because it is difficult to manipulate soil-bacterial community composition. Here, we exploit variation in soil fertility and microbial biodiversity across 20 farms to untangle suppression of aphids (Brevicoryne brassicae) through bottom–up and top–down channels. We planted Brassica oleracea plants in soil from each farm, manipulated single and dual infestations of aphids alone or with caterpillars (Pieris rapae), and exposed aphids to parasitoid wasps (Diaeretiella rapae) in the open field. We then used multi-model inference to identify the strongest soil-based predictors of herbivore growth and parasitism. We found that densities of Bacillus spp., a genus known to include plant-growth-promoting rhizobacteria, negatively correlated with aphid suppression by specialist parasitoids. Aphid parasitism also was disrupted on plants that had caterpillar damage, compared to plants attacked only by aphids. Relative abundance of Pseudomonas spp. bacteria correlated with higher aphid growth, although this appeared to be a direct effect, as aphid parasitism was not associated with this group of bacteria. Non-pathogenic soil bacteria are often shown to deliver benefits to plants, improving plant nutrition and the deployment of anti-herbivore defenses. However, our results suggest that these plant growth-promoting bacteria may also indirectly weaken top–down aphid suppression by parasitoids and directly improve aphid performance. Against a background of varying soil fertility, microbial biodiversity, competing herbivores, and natural enemies, we found that effects of non-pathogenic soil microbes on aphid growth outweighed those of nutritional factors. Therefore, predictions about the strength of plant defenses along resource gradients must be expanded to include microbial associates

Access to AgriculturalInputs, Technology and Information, Communicating with Farmers,and the Role of Women in Agriculture: Perceptions of Iraqi Extension Agents

The goal of this study was to gain a more comprehensive understanding ofaccess to inputs,technology and information available toIraqi extension agents,and to ascertain current farmercommunication strategies and gender roles within the diverse Iraq agricultural extension system.The conflicts, government policies, and economic sanctions that have enveloped Iraq over thelast several decades have significantly impacted access to agricultural resources. Iraqi extensionpersonnel participating inthe Iraq AgriculturalExtension Revitalization (IAER)programprovided their perspective on the availability of agricultural supplies, technology and relatedinformation. About two-thirds of the extension agents indicated that the flow and availability ofagricultural supplies has become less restricted and generally felt that there was greater accessto basic agricultural information compared to the previous decade. Despite perceivingnoticeable improvement overall in access to agricultural supplies and technology, over 83% ofthe program attendees agreed that access to agricultural inputs was currently insufficient tosuccessfully promote productive agricultural practices. An overwhelming preference for face-to-face communication by both farmers and extension personnel also limits the extent to whichagricultural information can be disseminated. In addition, several regional and gender-baseddifferences emerged.Notably, it appears that farmers donot approachfemaleextensionpersonnel equally, wherein better educated farmers are more likely to interact with femaleextensionagents.We suggest that an approach based on a horizontal exchange of knowledgebetween extension personnel and local farmers, coupled with a better integration of womenextension personnel, will help a revitalized Iraqi extension system achieve greater agriculturalsustainabilit

Sources of nitrogen for winter wheat in organic cropping systems

In organic cropping systems, legumes, cover crops, residue incorporation, and manure application are used to maintain soil fertility, but the contributions of these management practices to soil nitrogen (N) supply remain obscure. We examined potential sources of N for winter wheat (Triticum aestivum L.) in four experimental cropping systems established in 1997 on three soil types. Three of the four systems were under organic management. Topsoil N, depth of the A horizon, and cumulated inputs of N since 1997 were determined at plot level. Labile soil N pools (mineral N, potentially mineralizable N [PMN], microbial biomass N [MBN]) were monitored during two growth periods; at one site, biomass C/N ratios were also determined. Soil for labile N analysis was shielded from N inputs during spring application to isolate cumulated system effects. PMN and MBN were correlated across all sites and rotations (r2=0.72). The MBN corresponded to 46-85, 85-145 and 74-172 kg N ha-1 at the three sites and differed significantly between cropping systems, but MBN could not explain differences in wheat grain N yields. Instead, a multiple linear regression model explained 76 and 82% of the variation in grain N yields in organic cropping systems in 2007 and 2008, showing significant effects of, respectively, topsoil N, depth of A horizon, cumulated inputs of N, and N applied to winter wheat in manure. Thus, soil properties, and past and current management all contributed to winter wheat N supply

Effect of Arbuscular Mycorrhizal Fungi, Selenium and Biochar on Photosynthetic Pigments and Antioxidant Enzyme Activity Under Arsenic Stress in Mung Bean (Vigna radiata)

Environmental perturbations alter biochemical compounds in food crops. Arsenic (As), a toxic metalloid, is known to affect the cultivation of food crops in many regions of the world; however, the changes in chlorophyll, catalase (CAT), and proline in response to As stress and the role of stress relief substances remain largely unknown in mung bean (Vigna radiate L.). In this study, biochar (BC), arbuscular mycorrhizal fungi (AMF), and selenium (Se) were applied to soils as stress relief substances (under 30 mg kg-1 As stress), and the effects of BC, AMF, and Se on chlorophyll a, chlorophyll b, total chlorophyll, CAT activity, and proline content were studied in different mung bean genotypes. Under As stress, the chlorophyll a, chlorophyll b, and total chlorophyll contents in BARI mung 3, BARI mung 5, and BARI mung 8 were found statistically similar. Meanwhile, CAT activity increased in comparison to the control due to the application of BC, AMF, and Se in mung bean crops. However, proline was found significantly lower in AMF, BC, and Se-treated mung bean. This indicates that oxidative stress was potentially minimized in As-stressed mung bean crops due to the application of these stress relief substances. Notably, AMF was relatively effective against As stress in comparison to BC and Se. It is concluded that BC, AMF, and Se are all highly effective in enhancing antioxidant defenses as well as the nutritional quality of mung bean crops under As stress

YSOVAR: Mid-infrared Variability Among YSOs in the Star Formation Region GGD 12-15

S. J. Wolk, et al., “YSOVAR: Mid-infrared Variability Among YSOs in the Star Formation Region GGD 12-15”, The Astronomical Journal, Vol. 150(5), October 2015. © 2015. The American Astronomical Society. All rights reserved.We present an IR-monitoring survey with the $Spitzer$ Space Telescope of the star forming region GGD 12-15. Over 1000 objects were monitored including about 350 objects within the central 5 arcminutes which is found to be especially dense in cluster members. The monitoring took place over 38 days and is part of the Young Stellar Object VARiability (YSOVAR) project. The region was also the subject of a contemporaneous 67ks $Chandra$ observation. The field includes 119 previously identified pre-main sequence star candidates. X-rays are detected from 164 objects, 90 of which are identified with cluster members. Overall, we find that about half the objects in the central 5 arcminutes are young stellar objects based on a combination of their spectral energy distribution, IR variability and X-ray emission. Most of the stars with IR excess relative to a photosphere show large amplitude (>0.1 mag) mid-IR variability. There are 39 periodic sources, all but one of these is found to be a cluster member. Almost half of the periodic sources do not show IR excesses. Overall, more than 85% of the Class I, flat spectrum, and Class II sources are found to vary. The amplitude of the variability is larger in more embedded young stellar objects. Most of the Class~I/II objects exhibit redder colors in a fainter state, compatible with time-variable extinction. A few become bluer when fainter, which can be explained with significant changes in the structure of the inner disk. A search for changes in the IR due to X-ray events is carried out, but the low number of flares prevented an analysis of the direct impact of X-ray flares on the IR lightcurves. However, we find that X-ray detected Class II sources have longer timescales for change in the mid-IR than a similar set of non-X-ray detected Class IIs.Peer reviewe

Yield and Economic Performance of Organic and Conventional Cotton-Based Farming Systems – Results from a Field Trial in India

The debate on the relative benefits of conventional and organic farming systems has in recent time gained significant interest. So far, global agricultural development has focused on increased productivity rather than on a holistic natural resource management for food security. Thus, developing more sustainable farming practices on a large scale is of utmost importance. However, information concerning the performance of farming systems under organic and conventional management in tropical and subtropical regions is scarce. This study presents agronomic and economic data from the conversion phase (2007–2010) of a farming systems comparison trial on a Vertisol soil in Madhya Pradesh, central India. A cotton-soybean-wheat crop rotation under biodynamic, organic and conventional (with and without Bt cotton) management was investigated. We observed a significant yield gap between organic and conventional farming systems in the 1st crop cycle (cycle 1: 2007–2008) for cotton (229%) and wheat (227%), whereas in the 2nd crop cycle (cycle 2: 2009–2010) cotton and wheat yields were similar in all farming systems due to lower yields in the conventional systems. In contrast, organic soybean (a nitrogen fixing leguminous plant) yields were marginally lower than conventional yields (21% in cycle 1, 211% in cycle 2). Averaged across all crops, conventional farming systems achieved significantly higher gross margins in cycle 1 (+29%), whereas in cycle 2 gross margins in organic farming systems were significantly higher (+25%) due to lower variable production costs but similar yields. Soybean gross margin was significantly higher in the organic system (+11%) across the four harvest years compared to the conventional systems. Our results suggest that organic soybean production is a viable option for smallholder farmers under the prevailing semi-arid conditions in India. Future research needs to elucidate the long-term productivity and profitability, particularly of cotton and wheat, and the ecological impact of the different farming systems

Impaired Iron Status in Aging Research

Aging is associated with disturbances in iron metabolism and storage. During the last decade, remarkable progress has been made toward understanding their cellular and molecular mechanisms in aging and age-associated diseases using both cultured cells and animal models. The field has moved beyond descriptive studies to potential intervention studies focusing on iron chelation and removal. However, some findings remain controversial and inconsistent. This review summarizes important features of iron dyshomeostasis in aging research with a particular emphasis on current knowledge of the mechanisms underlying age-associated disorders in rodent models

Clinical outcomes of ED patients with bandemia

BackgroundAlthough an elevated white blood cell count is a widely utilized measure for evidence of infection and an important criterion for evaluation of systemic inflammatory response syndrome, its component band count occupies a more contested position within clinical emergency medicine. Recent studies indicate that bandemia is highly predictive of a serious infection, suggesting that clinicians who do not appreciate the value of band counts may delay diagnosis or overlook severe infections.ObjectivesWhereas previous studies focused on determining the quantitative value of the band count (ie, determining sensitivity, threshold for bandemia, etc.), this study directs attention to patient-centered outcomes, hypothesizing that the degree of bandemia predisposes patients to subsequent negative clinical outcomes associated with underappreciated severe infections.MethodsThis retrospective study of electronic medical records includes patients who initially presented to the emergency department (ED) with bandemia and were subsequently discharged from the ED. These patients were screened for repeat ED visits within 7 days and death within 30 days.ResultsIn patients with severe bandemia who were discharged from the ED, there was a 20.9% revisit rate at 7 days and a 4.9% mortality rate at 30 days, placing severely bandemic patients at 5 times significantly greater mortality compared to nonbandemic patients (P = .032).ConclusionOur review of patient outcomes suggests that the degree of bandemia, especially in the setting of concurrent tachycardia or fever, is associated with greater likelihood of negative clinical outcomes