Microbial communities associated with the larval gut and eggs of the Western corn rootworm.

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Flavia Dematheis

Full Text Available BACKGROUND: The western corn rootworm (WCR is one of the economically most important pests of maize. A better understanding of microbial communities associated with guts and eggs of the WCR is required in order to develop new pest control strategies, and to assess the potential role of the WCR in the dissemination of microorganisms, e.g., mycotoxin-producing fungi. METHODOLOGY/PRINCIPAL FINDINGS: Total community (TC DNA was extracted from maize rhizosphere, WCR eggs, and guts of larvae feeding on maize roots grown in three different soil types. Denaturing gradient gel electrophoresis (DGGE and sequencing of 16S rRNA gene and ITS fragments, PCR-amplified from TC DNA, were used to investigate the fungal and bacterial communities, respectively. Microorganisms in the WCR gut were not influenced by the soil type. Dominant fungal populations in the gut were affiliated to Fusarium spp., while Wolbachia was the most abundant bacterial genus. Identical ribosomal sequences from gut and egg samples confirmed a transovarial transmission of Wolbachia sp. Betaproteobacterial DGGE indicated a stable association of Herbaspirillum sp. with the WCR gut. Dominant egg-associated microorganisms were the bacterium Wolbachia sp. and the fungus Mortierella gamsii. CONCLUSION/SIGNIFICANCE: The soil type-independent composition of the microbial communities in the WCR gut and the dominance of only a few microbial populations suggested either a highly selective environment in the gut lumen or a high abundance of intracellular microorganisms in the gut epithelium. The dominance of Fusarium species in the guts indicated WCR larvae as vectors of mycotoxin-producing fungi. The stable association of Herbaspirillum sp. with WCR gut systems and the absence of corresponding sequences in WCR eggs suggested that this bacterium was postnatally acquired from the environment. The present study provided new insights into the microbial communities associated with larval guts and eggs of

Evaluation of SmartStax and SmartStax PRO maize against western corn rootworm and northern corn rootworm: efficacy and resistance management.

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Head, Graham P; Carroll, Matthew W; Evans, Sean P; Rule, Dwain M; Willse, Alan R; Clark, Thomas L; Storer, Nicholas P; Flannagan, Ronald D; Samuel, Luke W; Meinke, Lance J

2017-09-01

Cases of western corn rootworm (WCR) field-evolved resistance to Cry3Bb1 and other corn rootworm (CRW) control traits have been reported. Pyramid products expressing multiple CRW traits can delay resistance compared to single trait products. We used field studies to assess the pyramid CRW corn products, SmartStax (expressing Cry3Bb1 and Cry34Ab1/Cry35Ab1) and SmartStax PRO (expressing Cry3Bb1, Cry34Ab1/Cry35Ab1 and DvSnf7), at locations with high WCR densities and possible Cry3Bb1 resistance, and to assess the reduction in adult emergence attributable to DvSnf7 and other traits. Insect resistance models were used to assess durability of SmartStax and SmartStax PRO to WCR resistance. SmartStax significantly reduced root injury compared to non-CRW-trait controls at all but one location with measurable WCR pressure, while SmartStax PRO significantly reduced root injury at all locations, despite evidence of Cry3Bb1 resistance at some locations. The advantage of SmartStax PRO over SmartStax in reducing root damage was positively correlated with root damage on non-CRW-trait controls. DvSnf7 was estimated to reduce WCR emergence by approximately 80-95%, which modeling indicated will improve durability of Cry3Bb1 and Cry34Ab1/Cry35Ab1 compared to SmartStax. The addition of DvSnf7 in SmartStax PRO can reduce root damage under high WCR densities and prolong Cry3Bb1 and Cry34Ab1/Cry35Ab1 durability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Inhibition of seed germination by extracts of bitter Hawkesbury watermelon containing cucurbitacin, a feeding stimulant for corn rootworm (Coleoptera: Chrysomelidae).

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Martin, Phyllis A W; Blackburn, Michael

2003-04-01

Cucurbitacins are feeding stimulants for corn rootworm used in baits to control the adults of this insect pest. Corn rootworm larvae also feed compulsively on cucurbitacins. Cucurbitacins are reported to be gibberellin antagonists that may preclude their use as seed treatments for these soil-dwelling insects. The crude extract of a bitter Hawkesbury watermelon containing cucurbitacin E-glycoside significantly inhibited germination of watermelon, squash, and tomato seeds. Although the germination of corn seed was not significantly inhibited, root elongation was inhibited by crude extracts, but not by high-performance liquid chromatography-purified cucurbitacin E-glycoside. Therefore, the effects of the major components in the bitter watermelon extract (e.g., sugars) on seed germination and root elongation were determined. Pure sugars (glucose and fructose), at concentrations found in watermelon extract, mimicked the inhibition of seed germination and root elongation seen with the crude bitter Hawkesbury watermelon extract. Removal of these sugars may be necessary to use this extract as a bait for corn rootworm larvae as a seed or root treatment.

Genetic Markers for Western Corn Rootworm Resistance to Bt Toxin

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Flagel, Lex E.; Swarup, Shilpa; Chen, Mao; Bauer, Christopher; Wanjugi, Humphrey; Carroll, Matthew; Hill, Patrick; Tuscan, Meghan; Bansal, Raman; Flannagan, Ronald; Clark, Thomas L.; Michel, Andrew P.; Head, Graham P.; Goldman, Barry S.

2015-01-01

Western corn rootworm (WCR) is a major maize (Zea mays L.) pest leading to annual economic losses of more than 1 billion dollars in the United States. Transgenic maize expressing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely used for the management of WCR. However, cultivation of Bt-expressing maize places intense selection pressure on pest populations to evolve resistance. Instances of resistance to Bt toxins have been reported in WCR. Developing genet...

Field Trial Performance of Herculex XTRA (Cry34Ab1/Cry35Ab1) and SmartStax (Cry34Ab1/Cry35Ab1 + Cry3Bb1) Hybrids and Soil Insecticides Against Western and Northern Corn Rootworms (Coleoptera: Chrysomelidae).

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Johnson, K D; Campbell, L A; Lepping, M D; Rule, D M

2017-06-01

Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), and northern corn rootworm, Diabrotica barberi Smith and Lawrence (Coleoptera: Chrysomelidae), are important insect pests in corn, Zea mays L. For more than a decade, growers have been using transgenic plants expressing proteins from the bacterium Bacillus thuringiensis (Bt) to protect corn roots from feeding. In 2011, western corn rootworm populations were reported to have developed resistance to Bt hybrids expressing Cry3Bb1 and later found to be cross-resistant to hybrids expressing mCry3A and eCry3.1Ab. The identification of resistance to Cry3 (Cry3Bb1, mCry3A, and eCry3.1Ab) hybrids led to concerns about durability and efficacy of products with single traits and of products containing a pyramid of a Cry3 protein and the binary Bt proteins Cry34Ab1 and Cry35Ab1. From 2012 to 2014, 43 field trials were conducted across the central United States to estimate root protection provided by plants expressing Cry34Ab1/Cry35Ab1 alone (Herculex RW) or pyramided with Cry3Bb1 (SmartStax). These technologies were evaluated with and without soil-applied insecticides to determine if additional management measures provided benefit where Cry3 performance was reduced. Trials were categorized for analysis based on rootworm damage levels on Cry3-expressing hybrids and rootworm feeding pressure within each trial. Across scenarios, Cry34Ab1/Cry35Ab1 hybrids provided excellent root protection. Pyramided traits provided greater root and yield protection than non-Bt plus a soil-applied insecticide, and only in trials where larval feeding pressure exceeded two nodes of damage did Cry34Ab1/Cry35Ab1 single-trait hybrids and pyramided hybrids show greater root protection from the addition of soil-applied insecticides. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Secondary Contact and Admixture between Independently Invading Populations of the Western Corn Rootworm, Diabrotica virgifera virgifera in Europe

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Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas

2012-01-01

The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a Bayesian analysis of the population structure and in an approximate Bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed. PMID:23189184

Synthetic feeding stimulants enhance insecticide activity against western corn rootworm larvae, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae)

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In behavioral bioassays, the addition of a synthetic feeding stimulant blend improved the efficacy of the insecticide thiamethoxam against neonate western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae. In 4-h bioassays, the concentration of thiamethoxam required for 50% mortality (LC...

A new artificial diet for western corn rootworm larvae is compatible with and detects resistance to all current Bt toxins

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Insect resistance to transgenic crops expressing one or more genes from Bacillus thuringiensis Berliner (Bt) is a growing concern for farmers, regulatory agencies, the seed industry, and researchers alike. Western corn rootworm (Diabrotica virgifera virgifera LeConte) is a pest of corn (Zea mays L.)...

Assessment of fitness costs in Cry3Bb1 resistant and susceptible western corn rootworm (Coleoptera:Chrysomelidae) laboratory colonies

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Maize production in the United States is dominated by plants genetically modified with transgenes from Bacillus thuringiensis (Bt). Varieties of Bt maize expressing Cry3Bb endotoxins that specifically target corn rootworms (genus Diabrotica) have proven highly efficacious. Howeve...

THE IMPORTANCE OF WESTERN CORN ROOTWORM IN CONTINUOUS MAIZE

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Marija Ivezić

2006-06-01

Full Text Available Western Corn Rootworm (Diabrotica virgifera virgifera LeConte is considered to be one of the most important and potentially most severe pest of maize worldwide. The pest was detected in Croatia for the first time in 1995. Since then it has been spread over all areas with maize production in Croatia. The economically most efficient and preventive control measure is crop rotation and growing maize hybrids that show tolerance to WCR. The trials were settled in the area near Dubosevica where in 2002 and 2003 the economic damages caused by WCR were up to 80%. The aim of this investigation is to determine damages on maize root caused by WCR and loss in grain yield on commercial maize hybrids in continuous farming. Pheromone traps, type Csal♀m♂N®, were used in order to monitor WCR population dynamics. In the period of two months, 366 WCR adult beetles in total were captured. Root damage was evaluated according to Iowa Node Injury Scale and grain yield was measured and corrected to 14% moisture. Furthermore, the plant lodging, as a consequence of larval feeding, was assessed. The results have shown that root damage for hybrid Bc 5982 was 1.15, and 0.73 damage was on Pr 35p 12 roots. The grain yield obtained from hybrid Bc 5982 was 11.7 t/ha, and Pr 35p 12 had 12.3 t/ha. Statistical analyses showed that there were no significant differences in root damage and losses in grain yield between the two investigated hybrids. Results of this investigation indicate that growing maize for 2 to 3 years in continuous farming, in the same field, would not cause economically significant loss in maize gain yield.

IPM Use With the Deployment of a Non-High Dose Bt Pyramid and Mitigation of Resistance for Western Corn Rootworm (Diabrotica virgifera virgifera).

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Martinez, J C; Caprio, M A

2016-03-27

Recent detection of western corn rootworm resistance to Bt (Bacillus thuringiensis) corn prompted recommendations for the use of integrated pest management (IPM) with planting refuges to prolong the durability of Bt technologies. We conducted a simulation experiment exploring the effectiveness of various IPM tools at extending durability of pyramided Bt traits. Results indicate that some IPM practices have greater merits than others. Crop rotation was the most effective strategy, followed by increasing the non-Bt refuge size from 5 to 20%. Soil-applied insecticide use for Bt corn did not increase the durability compared with planting Bt with refuges alone, and both projected lower durabilities. When IPM participation with randomly selected management tools was increased at the time of Bt commercialization, durability of pyramided traits increased as well. When non-corn rootworm expressing corn was incorporated as an IPM option, the durability further increased.For corn rootworm, a local resistance phenomenon appeared immediately surrounding the resistant field (hotspot) and spread throughout the local neighborhood in six generations in absence of mitigation. Hotspot mitigation with random selection of strategies was ineffective at slowing resistance, unless crop rotation occurred immediately; regional mitigation was superior to random mitigation in the hotspot and reduced observed resistance allele frequencies in the neighborhood. As resistance alleles of mobile pests can escape hotspots, the scope of mitigation should extend beyond resistant sites. In the case of widespread resistance, regional mitigation was less effective at prolonging the life of the pyramid than IPM with Bt deployment at the time of commercialization. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the United States.

Evaluation of five methods for total DNA extraction from western corn rootworm beetles.

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Hong Chen

Full Text Available BACKGROUND: DNA extraction is a routine step in many insect molecular studies. A variety of methods have been used to isolate DNA molecules from insects, and many commercial kits are available. Extraction methods need to be evaluated for their efficiency, cost, and side effects such as DNA degradation during extraction. METHODOLOGY/PRINCIPAL FINDINGS: From individual western corn rootworm beetles, Diabrotica virgifera virgifera, DNA extractions by the SDS method, CTAB method, DNAzol reagent, Puregene solutions and DNeasy column were compared in terms of DNA quantity and quality, cost of materials, and time consumed. Although all five methods resulted in acceptable DNA concentrations and absorbance ratios, the SDS and CTAB methods resulted in higher DNA yield (ng DNA vs. mg tissue at much lower cost and less degradation as revealed on agarose gels. The DNeasy kit was most time-efficient but was the costliest among the methods tested. The effects of ethanol volume, temperature and incubation time on precipitation of DNA were also investigated. The DNA samples obtained by the five methods were tested in PCR for six microsatellites located in various positions of the beetle's genome, and all samples showed successful amplifications. CONCLUSION/SIGNIFICANCE: These evaluations provide a guide for choosing methods of DNA extraction from western corn rootworm beetles based on expected DNA yield and quality, extraction time, cost, and waste control. The extraction conditions for this mid-size insect were optimized. The DNA extracted by the five methods was suitable for further molecular applications such as PCR and sequencing by synthesis.

Kernel compositions of glyphosate-tolerant and corn rootworm-protected MON 88017 sweet corn and insect-protected MON 89034 sweet corn are equivalent to that of conventional sweet corn (Zea mays).

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Curran, Kassie L; Festa, Adam R; Goddard, Scott D; Harrigan, George G; Taylor, Mary L

2015-03-25

Monsanto Co. has developed two sweet corn hybrids, MON 88017 and MON 89034, that contain biotechnology-derived (biotech) traits designed to enhance sustainability and improve agronomic practices. MON 88017 confers benefits of glyphosate tolerance and protection against corn rootworm. MON 89034 provides protection against European corn borer and other lepidopteran insect pests. The purpose of this assessment was to compare the kernel compositions of MON 88017 and MON 89034 sweet corn with that of a conventional control that has a genetic background similar to the biotech sweet corn but does not express the biotechnology-derived traits. The sweet corn samples were grown at five replicated sites in the United States during the 2010 growing season and the conventional hybrid and 17 reference hybrids were grown concurrently to provide an estimate of natural variability for all assessed components. The compositional analysis included proximates, fibers, amino acids, sugars, vitamins, minerals, and selected metabolites. Results highlighted that MON 88017 and MON 89034 sweet corns were compositionally equivalent to the conventional control and that levels of the components essential to the desired properties of sweet corn, such as sugars and vitamins, were more affected by growing environment than the biotech traits. In summary, the benefits of biotech traits can be incorporated into sweet corn with no adverse effects on nutritional quality.

Asymmetric Total Synthesis of Four Stereoisomers of the Sex Pheromone of the Western Corn Rootworm

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Zhi-Feng Sun

2018-03-01

Full Text Available A convergent synthesis of four stereoisomers of the sex pheromone of the western corn rootworm (8-methyldecan-2-yl propionate, 1 from commercially available chiral starting materials is reported. The key step was Julia–Kocienski olefination between chiral BT-sulfone and chiral aldehyde. This synthetic route provided the four stereoisomers of 1 in 24–29% total yield via a six-step sequence. The simple scale-up strategy provides a new way to achieve the asymmetric synthesis of the sex pheromone.

Histopathological Effects of Bt and TcdA Insecticidal Proteins on the Midgut Epithelium of Western Corn Rootworm Larvae (Diabrotica virgifera virgifera

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Andrew J. Bowling

2017-05-01

Full Text Available Western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte is a major corn pest in the United States, causing annual losses of over $1 billion. One approach to protect against crop loss by this insect is the use of transgenic corn hybrids expressing one or more crystal (Cry proteins derived from Bacillus thuringiensis. Cry34Ab1 and Cry35Ab1 together comprise a binary insecticidal toxin with specific activity against WCR. These proteins have been developed as insect resistance traits in commercialized corn hybrids resistant to WCR feeding damage. Cry34/35Ab1 is a pore forming toxin, but the specific effects of Cry34/35Ab1 on WCR cells and tissues have not been well characterized microscopically, and the overall histopathology is poorly understood. Using high-resolution resin-based histopathology methods, the effects of Cry34/35Ab1 as well as Cry3Aa1, Cry6Aa1, and the Photorhabdus toxin complex protein TcdA have been directly visualized and documented. Clear symptoms of intoxication were observed for all insecticidal proteins tested, including swelling and sloughing of enterocytes, constriction of midgut circular muscles, stem cell activation, and obstruction of the midgut lumen. These data demonstrate the effects of these insecticidal proteins on WCR midgut cells, and the collective response of the midgut to intoxication. Taken together, these results advance our understanding of the insect cell biology and pathology of these insecticidal proteins, which should further the field of insect resistance traits and corn rootworm management.

PROTECTION AGAINST WESTERN CORN ROOTWORM ADULTS (DIABROTICA VIRGIFERA VIRGIFERA LECONTE IN BARANYA COUNTY (HUNGARY

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Veronika TÓTH

2006-05-01

Full Text Available With the settle of western corn rootworm (Diabrotica virgifera virgifera LeConte (from 1995, the spectrum of pests with potential damage in Hungary increased. The pest was followed by trapping (with sex-pheromone and colour traps. In 2000 the pest was found in whole Hungary (except Győr-Moson-Sopron, Vas and Szabolcs-Szatmár-Bereg county, in extremely fl uctuating number (1-700 pest/trap. In the southern region for maize production (Csongrád, Békés, Bács-Kiskun, Baranya, Tolna county, where the pest was found fi rst, the number of it increased in various centres. Based on these data, we carried out insecticide experiment.

RELATIONS AMONG WESTERN CORN ROOTWORM RESISTANCE TRAITS AND ELEMENTS CONCENTRATION IN MAIZE GERMPLASM ROOTS

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Andrija Brkić

2015-06-01

Full Text Available Western corn rootworm – WCR (Diabrotica virgifera virgifera LeConte is an important maize pest in Croatia. Using native resistance of maize germplasm could reduce chemical treatments and other costs in maize production. Objectives of this study were: i to assess variability of WCR resistance traits (root injury, regrowth and size and concentrations of nine elements in roots of 128 maize genotypes, and ii to determine correlations among the traits and ion concentrations. Results revealed high variability of maize genotypes for both WCR resistance traits and ion concentrations. Significant moderate negative correlations (>-0.4 were detected between root injury and boron as well as between root regrowth and iron, manganese and zinc concentrations in root. Consequently, ion concentration in maize roots might have an impact on WCR resistance research.

Nitrogen Rate Effects on Cry3Bb1 and Cry3Bb1 + Cry34/35Ab1 Expression in Transgenic Corn Roots, Resulting Root Injury, and Corn Rootworm Beetle Emergence.

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Leaf, T M; Ostlie, K R

2017-06-01

Nitrogen (N) application rates have been recommended historically for maximum economic yield of corn (Zea mays L.), but not for optimal expression or impacts of Bt (Bacillus thuringiensis Berliner) Cry protein(s) on target insects. This study explored the need to adjust N rates to optimize expression of corn rootworm-active Bt (Bt-RW) protein(s) in a single and a pyramided trait hybrid and resulting impacts on beetle emergence and root injury, under field conditions. The experiment featured a factorial treatment arrangement in a split-plot randomized complete block design with six N rates as the main plots and three hybrids (MON88017 expressing Cry3Bb1, MON88017 x DAS-59122 expressing Cry3Bb1 + Cry34/35Ab1, and a non-Bt-RW hybrid) as the subplots. Corn roots were sampled at the beginning of, and after, peak larval feeding to determine Bt-expression levels using an enzyme-linked immunosorbent assay. Beetles were collected every 2-3 d during emergence using cut-plant emergence cages. Cry3Bb1 expression was significantly reduced when little or no N was applied. Cry34Ab1 and Cry35Ab1 expression was highly variable and unaffected by N rate. Beetle emergence increased with N rate in the non-Bt-RW hybrid while root injury declined. Provided Bt-RW hybrids had sufficient applied N, root injury was relatively low. Results indicate that N management could affect Bt-RW expression and success of insect resistance management plans provided N is applied at rates that enhance production of susceptible beetles emerging from the non-Bt-RW (refuge) hybrid, and achieve optimal expression and efficacy of Bt traits. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

EFFECT OF DIFFERENT TRAPS ON CAPTURES OF ADULT CORN ROOTWORM BEETLES (Diabrotica virgifera virgifera LeConte IN EAST SLAVONIA

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Marija Ivezić

2002-12-01

Full Text Available In 1995 the corn rootworm (Diabrotica virgifera virgifera LeConte was detected for the first time in east Slavonia, Croatia. Its expansion to the west part has been very fast and from year to year populations of the pest are higher, especially when corn is planted after corn. The aim of this investigation was to find the best trap for monitoring Diabrotica. The studies were conducted by using three types of traps: the USA Trece lure trap, Multigard yellow sticky trap and Hungarian pheromone trap. The treatments were replicated four times in a maize field located in the east of Croatia, very near to the Yugoslavia border. The traps were placed in the field on the 23rd of June and the experiment continued until the 15th of September. Pheromone and Multigard sticky traps were replaced with new ones each month. Traps were positioned 60 m apart within a row and 70 m apart across maize rows. Silking occurred from 30 June to 8 August (exposed silk thoroughly brown and dry. This year was extremely dry, and the first beetles were noticed on the 15th of June. It was 20 days earlier than in 1999. Adult rootworm beetles were removed from the traps once weekly. Pheromone traps captured the most beetles (2263, Multigard sticky traps caught the second most (214 and lure traps the fewest (182 for the whole period. After the replacement of pheromone and Multigard traps, the capture of beetles increased. Of the total number of beetles caught, 85.10% was caught by the pheromone traps, 8.05% by the Multigard sticky traps and 6.85% by the lure traps. Due to this year’s dryness (50% less rainfall than the 20 year average, the investigation should be continued in the future to get more precise results.

Genetic markers for western corn rootworm resistance to Bt toxin.

Science.gov (United States)

Flagel, Lex E; Swarup, Shilpa; Chen, Mao; Bauer, Christopher; Wanjugi, Humphrey; Carroll, Matthew; Hill, Patrick; Tuscan, Meghan; Bansal, Raman; Flannagan, Ronald; Clark, Thomas L; Michel, Andrew P; Head, Graham P; Goldman, Barry S

2015-01-07

Western corn rootworm (WCR) is a major maize (Zea mays L.) pest leading to annual economic losses of more than 1 billion dollars in the United States. Transgenic maize expressing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely used for the management of WCR. However, cultivation of Bt-expressing maize places intense selection pressure on pest populations to evolve resistance. Instances of resistance to Bt toxins have been reported in WCR. Developing genetic markers for resistance will help in characterizing the extent of existing issues, predicting where future field failures may occur, improving insect resistance management strategies, and in designing and sustainably implementing forthcoming WCR control products. Here, we discover and validate genetic markers in WCR that are associated with resistance to the Cry3Bb1 Bt toxin. A field-derived WCR population known to be resistant to the Cry3Bb1 Bt toxin was used to generate a genetic map and to identify a genomic region associated with Cry3Bb1 resistance. Our results indicate that resistance is inherited in a nearly recessive manner and associated with a single autosomal linkage group. Markers tightly linked with resistance were validated using WCR populations collected from Cry3Bb1 maize fields showing significant WCR damage from across the US Corn Belt. Two markers were found to be correlated with both diet (R2 = 0.14) and plant (R2 = 0.23) bioassays for resistance. These results will assist in assessing resistance risk for different WCR populations, and can be used to improve insect resistance management strategies. Copyright © 2015 Flagel et al.

Development of a CO2 -releasing coformulation based on starch, Saccharomyces cerevisiae and Beauveria bassiana attractive towards western corn rootworm larvae.

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Vemmer, Marina; Schumann, Mario; Beitzen-Heineke, Wilhelm; French, Bryan W; Vidal, Stefan; Patel, Anant V

2016-11-01

CO 2 is known as an attractant for many soil-dwelling pests. To implement an attract-and-kill strategy for soil pest control, CO 2 -emitting formulations need to be developed. The aim of the present work was to develop a slow-release bead system in order to bridge the gap between application and hatching of western corn rootworm larvae. We compared different Ca-alginate beads containing Saccharomyces cerevisiae for their potential to release CO 2 over a period of several weeks. The addition of starch improved CO 2 release, resulting in significantly higher CO 2 concentrations in soil for at least 4 weeks. The missing amylase activity was compensated for either by microorganisms present in the soil or by coencapsulation of Beauveria bassiana. Formulations containing S. cerevisiae, starch and B. bassiana were attractive for western corn rootworm larvae within the first 4 h following exposure; however, when considering the whole testing period, the maize root systems remained more attractive for the larvae. Coencapsulation of S. cerevisiae, starch and B. bassiana is a promising approach for the development of attractive formulations for soil applications. For biological control strategies, the attractiveness needs to be increased by phagostimuli to extend contact between larvae and the entomopathogenic fungus growing out of these formulations. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Impact of Cry3Bb1-expressing Bt maize on adults of the western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae).

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Meissle, Michael; Hellmich, Richard L; Romeis, Jörg

2011-07-01

Genetically engineered maize producing insecticidal Cry3Bb1 protein from Bacillus thuringiensis (Bt) is protected from root damage by corn rootworm larvae. An examination was made to establish whether western corn rootworm (Diabrotica virgifera virgifera) adults are affected by Cry3Bb1-expressing maize (MON88017) when feeding on above-ground tissue. In laboratory bioassays, adult D. v. virgifera were fed for 7 weeks with silk, leaves or pollen from Bt maize or the corresponding near-isoline. Male, but not female, survival was reduced in the Bt-leaf treatment compared with the control. Female weight was lower when fed Bt maize, and egg production was reduced in the Bt-silk treatment. ELISA measurements demonstrated that beetles feeding on silk were exposed to higher Cry3Bb1 concentrations than beetles collected from Bt-maize fields in the United States. In contrast to silk and pollen, feeding on leaves resulted in high mortality and low fecundity. Females feeding on pollen produced more eggs than on silk. C:N ratios indicated that silk does not provide enough nitrogen for optimal egg production. Direct effects of Cry3Bb1 on adult beetles could explain the observed effects, but varietal differences between Bt and control maize are also possible. The impact of Bt maize on adult populations, however, is likely to be limited. Copyright © 2011 Society of Chemical Industry.

Germline transformation of the western corn rootworm, Diabrotica virgifera virgifera.

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Chu, F; Klobasa, W; Wu, P; Pinzi, S; Grubbs, N; Gorski, S; Cardoza, Y; Lorenzen, M D

2017-08-01

The western corn rootworm (WCR), a major pest of maize, is notorious for rapidly adapting biochemically, behaviourally and developmentally to a variety of control methods. Despite much effort, the genetic basis of WCR adaptation remains a mystery. Since transformation-based applications such as transposon tagging and enhancer trapping have facilitated genetic dissection of model species such as Drosophila melanogaster, we developed a germline-transformation system for WCR in an effort to gain a greater understanding of the basic biology of this economically important insect. Here we report the use of a fluorescent-marked Minos element to create transgenic WCR. We demonstrate that the transgenic strains express both an eye-specific fluorescent marker and piggyBac transposase. We identified insertion-site junction sequences via inverse PCR and assessed insertion copy number using digital droplet PCR (ddPCR). Interestingly, most WCR identified as transgenic via visual screening for DsRed fluorescence proved to carry multiple Minos insertions when tested via ddPCR. A total of eight unique insertion strains were created by outcrossing the initial transgenic strains to nontransgenic WCR mates. Establishing transgenic technologies for this beetle is the first step towards bringing a wide range of transformation-based tools to bear on understanding WCR biology. © 2017 The Royal Entomological Society.

Sublethal effects of Cry 1F Bt corn and clothianidin on black cutworm (Lepidoptera: Noctuidae) larval development.

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Kullik, Sigrun A; Sears, Mark K; Schaafsma, Arthur W

2011-04-01

Black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), is an occasional pest of maize (corn), Zea mays L., that may cause severe stand losses and injury to corn seedlings. The efficacy of the neonicotinoid seed treatment clothianidin at two commercially available rates and their interaction with a transgenic corn hybrid (Bt corn), trait expressing the Bacillus thuringiensis variety aizawai insecticidal toxin Cry 1Fa2, against black cutworm larvae was investigated. Clothianidin at a rate of 25 mg kernel(-1) on Bt corn increased larval mortality and reduced larval weight gains additively. In contrast, weights of larvae fed non-Bt corn seedlings treated with clothianidin at a rate of 25 mg kernel(-1) increased significantly, suggesting either compensatory overconsumption, hormesis, or hormoligosis. Both Bt corn alone and clothianidin at a rate of 125 mg kernel(-1) applied to non-Bt corn seedlings caused increased mortality and reduced larval weight gains. In two field trials, plots planted with Bt corn hybrids consistently had the highest plant populations and yields, regardless of whether they were treated with clothianidin at the lower commercial rate of 25 mg kernel(-1) The use of Bt corn alone or in combination with the low rate of clothianidin (25 mg kernel(-1)) seems suitable as a means of suppressing black cutworm in no-tillage cornfields, although rescue treatments may still be necessary under severe infestations. Clothianidin alone at the low rate of 25 mg kernel(-1) is not recommended for black cutworm control until further studies of its effects on larval physiology and field performance have been completed.

On-Plant Larval Movement and Feeding Behavior of Fall Armyworm (Lepidoptera: Noctuidae) on Reproductive Corn Stages.

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Pannuti, L E R; Baldin, E L L; Hunt, T E; Paula-Moraes, S V

2016-02-01

Spodoptera frugiperda J.E. Smith (fall armyworm) is considered one of the most destructive pests of corn throughout the Americas. Although this pest has been extensively studied, little is known about its larval movement and feeding behavior on reproductive compared to vegetative corn stages. Thus, we conducted studies with two corn stages (R1 and R3) and four corn plant zones (tassel, above ear, ear zone, and below ear) in the field at Concord, NE (USA), and in the field and greenhouse at Botucatu, SP (Brazil), to investigate on-plant larval movement. The effects of different corn tissues (opened tassel, closed tassel, silk, kernel, and leaf), two feeding sequence scenarios (closed tassel-leaf-silk-kernel and leaf-silk-kernel), and artificial diet (positive control) on larval survival and development were also evaluated in the laboratory. Ear zone has a strong effect on feeding choice and survival of fall armyworm larvae regardless of reproductive corn stage. Feeding site choice is made by first-instar. Corn leaves of reproductive plants were not suitable for early instar development, but silk and kernel tissues had a positive effect on survival and development of fall armyworm larvae on reproductive stage corn. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

RESOURCE ALLOCATION IN A MAIZE BREEDING PROGRAM FOR NATIVE RESISTANCE TO WESTERN CORN ROOTWORM

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Ivan Brkić

2012-06-01

Full Text Available The objective of this study was to determine the optimum allocation of the number of plants sampled per plot and number of locations and years required for screening maize genotypes for reduced root damage caused by western corn rootworm (WCR larvae, major pest of maize in Croatia, Europe and in the USA. Field trials were conducted on two locations Eastern Croatia, a major maize production area with natural WCR occurrence under continuous maize growing conditions. The trials were set as an incomplete lattice block design in two replications in 2007, 2008 and 2009 including 128 genotypes from various maize gene-pools. Our results suggest that the effect of year and respective interactions including year were the most important factors in maize breeding programs for native resistance to WCR. Thus, screening germplasm for WCR resistance should be made in a multi-year experiment, but not necessarily as a multi-location experiment. Resource optimization should be done by reducing number of roots per plot to minimum 4 sampled plants due to small within-plot environmental variance.

Containment of the western corn rootworm Diabrotica v.virgifera: continued successful management 2008 in southern Switzerland by monitoring and crop rotation.

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Hummel, Hans E; Bertossa, M

2009-01-01

Diabrotica virgifera virgifera LeConte (Col.: Chrysomelidae), known as western corn rootworm (WCR) and endemic in North America, invaded Europe about two decades ago. Various unsuccessful attempts have been made to eradicate it from the Old World. Management with a variety of strategies is the option now remaining. WCR management in Southern Switzerland by a unique containment approach has been practiced successfully since 2003 using biotechnical means. Without any chemical pesticides or GMO input, the Swiss government mandated adherence to strict crop rotation. In addition to the economic benefits of this relatively simple approach, the environment was saved a considerable burden of pesticide applications. Other countries are invited to follow this example of sustainable pest management.

Successful application of entomopathogenic nematodes for the biological control of western corn rootworm larvae in Europe – a mini review

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Toepfer, Stefan

2014-02-01

Full Text Available 10 years of joint efforts in research and development have led to a nematode-based biological control solution for one of the most destructive maize pests, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae. Commercially mass-produced Heterorhabditis species of beneficial entomopathogenic nematodes are ready to use. They can be applied into the soil during sowing of maize for controlling the subsequently hatching larvae of D. virgifera virgifera thus preventing root feeding and damage to maize. Policy bodies, decision makers and farmers are advised to consider biological control as one of the alternatives to synthetic pesticides in maize production, and according to the EC Directive on the sustainable use of pesticides and implementation of integrated pest management.

On the influence of different host plants and of insecticide treatments on the population development of the western corn rootworm Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae

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Fora, Ciprian George

2014-02-01

Full Text Available D. virgifera virgifera is classified as a quarantine pest in Germany, therefore the trials, presented in this paper, were performed in the western part of Romania, where the pest is well established since more than ten years. The field tests were carried out in close collaboration with Banat’s University of Agricultural Sciences and Veterinary Medicine, Timişoara. On sites highly infested by D. virgifera virgifera, 1 m² plots in four replications per variable were planted with maize for the chemical treatments and alternative crops (cereals and weeds. Gauze covered hatch cages were used for weekly counts of the emerged adult Diabrotica during the hatch period from mid of June to mid of August. It could be asserted that matured cereals are no host-plants for the western corn rootworm. In four years of trials not even one adult beetle hatched in the related cages. Setaria viridis and Digitaria sanguinalis reduced the number of hatched imagines significantly, nevertheless some individuals survived. Therefore an effective herbicide management against grass weeds in maize is recommended to limit the chance of survival of the pest. Clothianidin and Tefluthrin are effective against D. virgifera virgifera. 20% to 100% efficiency was assessed in the trials, strongly depending on precipitation and soil moisture in time of application. The insecticides decreased the maize root injury caused by larvae of the western corn rootworm significantly.

Monitoring techniques of the western corn rootworm are the precursor to effective IPM strategies.

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Lemic, Darija; Mikac, Katarina M; Kozina, Antonela; Benitez, Hugo A; McLean, Christopher M; Bažok, Renata

2016-02-01

The western corn rootworm (WCR) is economically the most important pest of maize in Croatia. To predict WCR adult population abundance and variability, traditional, genetic and morphometric monitoring of populations was conducted over time through each phase of the WCR invasion process in Croatia. Through traditional monitoring it was shown that WCR established their current population and reached economic densities after 14 years persisting in the study area. Regression-tree-based modelling showed that the best predictor of WCR adult abundance was the total amount of rainfall. Genetic monitoring indicated that genetic differentiation increased over time at the intrapopulation level, and morphometric monitoring indicated that wing morphotypes varied according to edaphic landscape changes. Traditional population metric surveys are important in WCR integrated pest management (IPM), as such surveys can be effectively used to predict population abundances. Novel-use monitoring techniques such as genetics and geometric morphometrics can be used to provide valuable information on variation within and among populations. The monitoring techniques presented herein provide sound data to assist in the understanding of both WCR ecology and population genetics and may provide more information than that currently available using traditional techniques (e.g. sticky traps), and as such these additional techniques should be written into IPM for WCR. © 2015 Society of Chemical Industry.

Development of the Western corn rootworm, Diabrotica virgifera virgifera in soil

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Ľudovít CAGÁŇ

2016-12-01

Full Text Available Monitoring of developmental stages of the Western corn rootworm (WCR (Diabrotica virgifera virgifera is an important aspect of its control. In the experiment there were analysed randomly selected plants of maize on six localities in western Slovakia, in the years 2008-2010 a 2014-2015. The aim of the study was to identify exact time of the emergence of the WCR adults in the consequence of different years and different localities and to find the best date for their eradication. The most of the WCR individuals at the northern locality were observed on 29 June and the first adults were found on 07 June, during colder year 2006. The development started about nine days earlier in the next year in southern Slovakia, because of extremely hot weather. The population of pest increased slower in 2008 than in previous years, and the highest appearance was monitored up-to 02 July. The first adults were monitored on 27 June in the years 2009-2010 as well as 2014-2015. Generally, the highest numbers of the first instar larvae were observed on 22 June at the locality Čiližská Radvaň. The second instar larvae and the most of adults was found on 20 June in Sokolce. On 29 June it was monitored the largest amount of the third instar larvae at the locality Čiližská Radvaň. The differences in the time of the emergence of adults depended on the year. Based on the monitoring in Slovakia, it can be expected the third instar larvae from second decade of June and the first adults in the last decade of June and in the first decade of July.

Historical and contemporary population genetics of the invasive western corn rootworm (Coleoptera: Chrysomelidae) in Croatia.

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Lemic, D; Mikac, K M; Bažok, R

2013-08-01

Classical population genetic analyses were used to investigate populations of the western corn rootworm, Diabrotica virgifera virgifera LeConte, in Croatia in 1996 and 2009. The number of alleles was low in both 1996 and 2009; however, more alleles were found in the putative populations surveyed in 2009. Croatia had only 51% of the alleles recorded from the United States and 69% from Europe. However, 10 private (unique) alleles were found in Croatia, which were not found previously in Europe. Most populations were out of Hardy-Weinberg equilibrium, although no linkage disequilibrium was found. Low to no genetic differentiation was found between population pairwise comparisons in 1996, with a greater level of differentiation found between populations sampled in 2009. Using the program STRUCTURE, a single genetic cluster was found for populations sampled in 1996 and 2009. However, two genetic clusters were detected when the 1996 and 2009 data were combined, indicating significant temporal differentiation. Isolation by distance pattern of gene flow characterized populations sampled in 2009 only when the most distant population of Ogulin (the head of the expansion front) was included in the analysis. When Ogluin was excluded from the 2009 analysis no isolation by distance pattern was found. The possible impact that control practices have had on the population genetics of D. v. virgifera in Croatia from 1996 to 2009 are discussed in light of the temporal genetics differences found.

Maize germplasm of eastern Croatia with native resistance to western corn rootworm (Diabrotica virgifera virgifera LeConte

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Brkić Andrija

2017-01-01

Full Text Available The western corn rootworm (Diabrotica virgifera virgifera LeConte; WCR is a serious maize pest in Croatia. The species was first registered in Europe in the early 1990s and since then became one of the most dangerous maize pests, especially in parts of Central and Southeast Europe. Larvae that feed on the maize roots cause the most serious damages in maize fields. Management of this pest is difficult and expensive, with possible serious impact on the environment. Native (or host-plant resistance of maize against WCR could provide new economically and ecologically sustainable options in WCR management. Main goal of this study was to assess the variability of maize germplasm, correlations among resistance traits, and detect potential sources of resistance that could be used in breeding programs in order to develop hybrids with higher level of resistance against WCR. To our knowledge, the first native resistant hybrid is yet to be registered. Results showed great variability of estimated germplasm. Effect of the genotype was significant in all environments, as well as many interactions between genotype and the environment. Significant interactions emphasize the importance of the environment in WCR native resistance research. Significant positive correlations among all traits were detected. Several inbred lines were selected as a potentially useful germplasm for resistance breeding programs.

Characterizing the mechanism of action of double-stranded RNA activity against western corn rootworm (Diabrotica virgifera virgifera LeConte.

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Renata Bolognesi

Full Text Available RNA interference (RNAi has previously been shown to be effective in western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte larvae via oral delivery of synthetic double-stranded RNA (dsRNA in an artificial diet bioassay, as well as by ingestion of transgenic corn plant tissues engineered to express dsRNA. Although the RNAi machinery components appear to be conserved in Coleopteran insects, the key steps in this process have not been reported for WCR. Here we characterized the sequence of events that result in mortality after ingestion of a dsRNA designed against WCR larvae. We selected the Snf7 ortholog (DvSnf7 as the target mRNA, which encodes an essential protein involved in intracellular trafficking. Our results showed that dsRNAs greater than or equal to approximately 60 base-pairs (bp are required for biological activity in artificial diet bioassays. Additionally, 240 bp dsRNAs containing a single 21 bp match to the target sequence were also efficacious, whereas 21 bp short interfering (si RNAs matching the target sequence were not. This result was further investigated in WCR midgut tissues: uptake of 240 bp dsRNA was evident in WCR midgut cells while a 21 bp siRNA was not, supporting the size-activity relationship established in diet bioassays. DvSnf7 suppression was observed in a time-dependent manner with suppression at the mRNA level preceding suppression at the protein level when a 240 bp dsRNA was fed to WCR larvae. DvSnf7 suppression was shown to spread to tissues beyond the midgut within 24 h after dsRNA ingestion. These events (dsRNA uptake, target mRNA and protein suppression, systemic spreading, growth inhibition and eventual mortality comprise the overall mechanism of action by which DvSnf7 dsRNA affects WCR via oral delivery and provides insights as to how targeted dsRNAs in general are active against insects.

Larval development of Spodoptera eridania and Spodoptera frugiperda fed on fresh ear of field corn expressing the Bt proteins (Cry1F and Cry1F + Cry1A.105 + Cry2Ab2)

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Bortolotto,Orcial Ceolin; Bueno,Adeney de Freitas; Queiroz,Ana Paula de; Silva,Gabriela Vieira

2016-01-01

ABSTRACT: The objective of this study was to evaluate extent of larval period, larval survival (%), food consumption, and pupal biomass of Spodoptera eridania and Spodoptera frugiperda (Lepidoptera: Noctuidae ) fed on fresh ears of field corn expressing Bt proteins (Cry1F and Cry1F+Cry1A.105+Cry2Ab2). Larvae of Spodoptera spp. survived less than two days when they consumed Bt corncobs and showed 100% mortality. Spodoptera eridania reared on non-Bt corn cobs showed higher larval development (...

Larval development of Spodoptera eridania and Spodoptera frugiperda fed on fresh ear of field corn expressing the Bt proteins (Cry1F and Cry1F + Cry1A.105 + Cry2Ab2

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Orcial Ceolin Bortolotto

Full Text Available ABSTRACT: The objective of this study was to evaluate extent of larval period, larval survival (%, food consumption, and pupal biomass of Spodoptera eridania and Spodoptera frugiperda (Lepidoptera: Noctuidae fed on fresh ears of field corn expressing Bt proteins (Cry1F and Cry1F+Cry1A.105+Cry2Ab2. Larvae of Spodoptera spp. survived less than two days when they consumed Bt corncobs and showed 100% mortality. Spodoptera eridania reared on non-Bt corn cobs showed higher larval development (21.6 days than S. frugiperda (18.4 days and lower viability (56.4% and 80.2% for S. eridania and S. frugiperda , respectively. A higher amount of corn grains was consumed by S. eridania (5.4g than by S. frugiperda (3.9g. In summary, this study demonstrated that the toxins Cry1F and Cry1F + Cry1A.105 + Cry2Ab2 expressed in fresh corn cobs contributed to protect ears of corn against S. frugiperda and the non-target pest S. eridania . However, itis important to monitor non-Bt cornfields because of the potential of both species to cause damage to ear sof corn.

Monitoring presence and advance of the alien invasive western corn rootworm beetle in eastern Slovenia with highly sensitive Metcalf traps.

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Hummel, H E; Urek, G; Modic, S; Hein, D F

2005-01-01

The American Chrysomelid beetle Diabrotica virgifera virgifera LeConte (D.v.v.), also called the western corn rootworm, spread from the location of its original introduction into Europe, Belgrade airport (BACA 1993), in all directions. Within a decade it occupied almost all countries of South-eastern and Central Europe. However, it reached Slovenia as late as 2003: Only 19 specimen were found in maize fields of the eastern and also western provinces. Already in the summer of 2004, their number had risen to 386 which were mainly found in the eastern provinces near the borders to Croatia, Austria and Hungary. For their monitoring, a simple trap is being described which can be acquired in high numbers at a very low price and can guaranty a most sensitive detection of beetles. The Metcalf cup trap which in Slovenia so far has been unknown performed the task of monitoring quite well at five locations. It will also facilitate the future search for new and increasing infestations. Comparing 2004 with the year 2003, D.v.v. expanded its range in eastern Slovenia by about 15 km. These new infestations will include territories in which fields of the regionally Important oil seed pumpkin Cucurbita pepo are located. With important traffic connections between South-eastern and Central Europe, Slovenia will occupy a bridgehead function in the preventive protection of maize from D.v.v. spreading into more northerly European regions including western Austria and southern Germany.

Desenvolvimento e mortalidade larval de Spodoptera frugiperda em folhas de milho tratadas com extrato aquoso de folhas de Azadirachta indica Larval development and mortality of Spodoptera frugiperda fed on corn leaves treated with aqueous extract from Azadirachta indica leaves

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Paulo Afonso Viana

2003-01-01

Full Text Available Estudou-se o efeito do extrato aquoso de folhas de nim sobre o desenvolvimento e a mortalidade de lagartas recém-eclodidas de Spodoptera frugiperda. Para constatação do efeito de contato e de ingestão, as lagartas foram pulverizadas e as folhas de milho submersas no extrato (10 mg.mL-1 em laboratório e/ou pulverizadas no campo com um pulverizador de CO2. Partes de folhas de milho tratadas foram colocadas em copos plásticos para alimentar as lagartas e trocadas a cada dois dias. Adjuvantes foram adicionados ao extrato visando melhorar sua aderência às superfícies tratadas. Os parâmetros avaliados foram a mortalidade e o desenvolvimento larval. As folhas de milho submergidas e pulverizadas com o extrato causaram elevada mortalidade (100% e prejudicaram o desenvolvimento das lagartas sobreviventes. Na avaliação realizada 10 dias após a aplicação, o espalhante adesivo e o óleo de soja misturados ao extrato melhoraram a eficiência deste. A mortalidade das lagartas ocorreu três dias após a aplicação do extrato e a sua pulverização diretamente sobre o inseto não prejudicou o desenvolvimento larval. O extrato aquoso de nim mostrou-se com potencial para o controle de S. frugiperda.The effect of aqueous extracts from neem leaves and spraying adjuvants were evaluated on development and mortality of neonate S. frugiperda larvae. Corn leaves were dipped in the aqueous extract (10 mg.mL-1 in the laboratory and/or sprayed in the field with a CO2 sprayer and placed in plastic cup for larvae rearing. The treated corn leaves were replaced every other day. Corn leaves submerged and sprayed with the extract caused high larval mortality (100% and showed a negative effect on the larval development. The spreading agent and soybean oil mixed with neem extract improved larval mortality at the end of the 10-day period. The aqueous extract caused lethal effect on S. frugiperda larvae after three days of the application and sprayed directly on the

Comparison of grain from corn rootworm resistant transgenic DAS-59122-7 maize with non-transgenic maize grain in a 90-day feeding study in Sprague-Dawley rats.

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He, X Y; Huang, K L; Li, X; Qin, W; Delaney, B; Luo, Y B

2008-06-01

DAS-59122-7 (59122) is a transgenic maize (Zea mays L.) that contains genes encoding Cry34Ab1 and Cry35Ab1 proteins from Bacillus thuringiensis Berliner strain 149B1 and phosphinothricin acetyltransferase (PAT) protein from Streptomyces viridochromogenes. Expression of these proteins in planta confers resistance to corn rootworms and other Coleopteran parasites and tolerance to herbicides containing glufosinate ammonium, respectively. In the current study, processed flours from 59122 maize grain or its near isogenic control line (091) were used at two concentrations (50% and 70% wt/wt) to produce diets that were fed to rats for 90 days in accordance with Chinese toxicology guidelines (GB15193.13-2003). A commercial AIN93G diet was used as an additional negative control. No significant differences in body weight and feed utilization were observed between rats consuming diets formulated with 59122 and 091 Control corn. Statistical differences (p<0.05) were observed in certain hematology and serum chemistry response variables between rats consuming diets formulated with 59122 or 091 Control flour compared to AIN93G diet. However, the mean value of these response variables in the 59122 groups were not statistically different from those observed in diets formulated with corresponding high and low concentrations of the flour from the 091 Control maize grain. Therefore, the statistical differences were considered to be related to consumption of diets containing high concentrations of maize flour (compared to AIN93G diets) regardless of source rather than to consumption of flour from 59122 maize grain. The results from this study demonstrated that 59122 maize grain is as safe as non-transgenic maize grain.

Comparison of the forage and grain composition from insect-protected and glyphosate-tolerant MON 88017 corn to conventional corn (Zea mays L.).

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McCann, Melinda C; Trujillo, William A; Riordan, Susan G; Sorbet, Roy; Bogdanova, Natalia N; Sidhu, Ravinder S

2007-05-16

The next generation of biotechnology-derived products with the combined benefit of herbicide tolerance and insect protection (MON 88017) was developed to withstand feeding damage caused by the coleopteran pest corn rootworm and over-the-top applications of glyphosate, the active ingredient in Roundup herbicides. As a part of a larger safety and characterization assessment, MON 88017 was grown under field conditions at geographically diverse locations within the United States and Argentina during the 2002 and 2003-2004 field seasons, respectively, along with a near-isogenic control and other conventional corn hybrids for compositional assessment. Field trials were conducted using a randomized complete block design with three replication blocks at each site. Corn forage samples were harvested at the late dough/early dent stage, ground, and analyzed for the concentration of proximate constituents, fibers, and minerals. Samples of mature grain were harvested, ground, and analyzed for the concentration of proximate constituents, fiber, minerals, amino acids, fatty acids, vitamins, antinutrients, and secondary metabolites. The results showed that the forage and grain from MON 88017 are compositionally equivalent to forage and grain from control and conventional corn hybrids.

On-plant movement and feeding of western bean cutworm (Lepidoptera: Noctuidae) early instars on corn.

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Paula-Moraes, S V; Hunt, T E; Wright, R J; Hein, G L; Blankenship, E E

2012-12-01

Western bean cutworm, Striacosta albicosta (Smith), has undergone a recent eastward expansion from the western U.S. Corn Belt to Pennsylvania and parts of Canada. Little is known about its ecology and behavior, particularly during the early instars, on corn (Zea mays L.). There is a narrow treatment window for larvae, and early detection of the pest in the field is essential. An understanding of western bean cutworm larval feeding and early-instar dispersal is essential to understand larval survival and establishment in corn. Studies were conducted in 2009 through 2011 in Nebraska to determine the feeding and dispersal of early-instar western bean cutworm on corn. The treatment design was a factorial with three corn stages (pretassel, tassel, and posttassel) and five corn plant zones (tassel, above ear, primary ear, secondary ear, and below ear) in a randomized complete block design. The effects of different corn tissues on larval survival and development were investigated in laboratory studies in a randomized complete block design during 2009 and 2011. Treatments were different corn tissues (leaf alone, leaf with developing tassel, pollen, pollen plus silk, and silk alone). Results demonstrated that neonate larvae move to the upper part of the plant, independent of corn stage. Larval growth was optimal when fed on tassel tissue. Overall results indicated a selective benefit for movement of the early instar to upper part of the plant.

The importance of the western corn rootworm (Diabrotica virgifera virgifera LeConte in Bavaria – local relevance and economic impact on single farms

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Köhler, Katrin

2014-02-01

Full Text Available The western corn rootworm (Diabrotica virgifera virgifera LeConte, holding a quarantine status in the European Union, was first discovered in 2007 in southern Bavaria. In the course of Diabrotica Research Program of Germany and the states of Bavaria and Baden-Württemberg, an economic accompanying research is conducted at single farm level in Bavaria. This aims to evaluate different adaptation measures concerning the eradication and containment strategies economically. The focus of the analysis is mainly the crop rotation and the reduction of the proportion of maize at farm level. InVeKoS-data are analyzed, in order to assess the economic relevance of the pest in Bavaria in a better way. These enable detailed information on the development of maize production and cropping intensity. Subsequently research regions are defined with a high maize density, expecting enhanced damage from the beetle. In these selected areas single farms are selected. For considerations on single farm level, farms with different farm types are chosen by which adaptation measures are evaluated and realistic impact assessment could be made. For the evaluation of the economic impacts a whole-farm simulation has been used to include indirect effects of different adoption strategies. Additional, semi-structured interviews were conducted at selected farms in order to prove the results of the case study, obtain more information about the consequences on farm level and to evaluate the proposed cultivation alternatives for maize. A benefit-cost analysis and the comparative analysis of possible damage caused by the beetle and cost adjustments complete the study.

Composition of grain and forage from insect-protected and herbicide-tolerant corn, MON 89034 × TC1507 × MON 88017 × DAS-59122-7 (SmartStax), is equivalent to that of conventional corn (Zea mays L.).

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Lundry, Denise R; Burns, J Austin; Nemeth, Margaret A; Riordan, Susan G

2013-02-27

Monsanto Company and Dow AgroSciences LLC have developed the combined-trait corn product MON 89034 × TC1507 × MON 88017 × DAS-59122-7 (SmartStax, a registered trademark of Monsanto Technology LLC). The combination of four biotechnology-derived events into a single corn product (stacking) through conventional breeding provides broad protection against lepidopteran and corn rootworm insect pests as well as tolerance to the glyphosate and glufosinate-ammonium herbicide families. The purpose of the work described here was to assess whether the nutrient, antinutrient, and secondary metabolite levels in grain and forage tissues of the combined-trait product are comparable to those in conventional corn. Compositional analyses were conducted on grain and forage from SmartStax, a near-isogenic conventional corn hybrid (XE6001), and 14 conventional reference hybrids, grown at multiple locations across the United States. No statistically significant differences between SmartStax and conventional corn were observed for the 8 components analyzed in forage and for 46 of the 52 components analyzed in grain. The six significant differences observed in grain components (p corn, as previously demonstrated for the single-event products.

Larval and pupal stage of Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae in sweet and field corn genotypes Fases larval e pupal de Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae em genótipos de milho doce e comum

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L. M. Santos

2003-11-01

Full Text Available Spodoptera frugiperda, the fall armyworm, is a very significant polyphagous pest due to the damages it causes, and control difficulties. Lack of information about its impact on sweet corn motivated a comparison of its biology, with respect to the larval and pupal stages, among the genotypes ELISA, BR 400 (sweet corns, and BR PAMPA (field corn. In laboratory conditions (25 ± 1ºC; 70 ± 10% RH; photophase 12 hours, 35 caterpillars were individualized and fed daily with 3.14 cm² sections of corn leaves from the referred-to genotypes, cultivated in plots in the experimental area of the Departament of Fitossanidade, UFRGS, Porto Alegre, RS from October to November 2000. The caterpillars were weighed daily; after each molt, the cephalic capsules were collected and measured (in width, to establish growth rate; pupae were weighed and sexed when 24 hours old. The duration of the larval instars, the pupal sex ratio, and the mortality of larvae and pupae were evaluated. In the first three instars there were no differences registered in capsule width. In the fourth and fifth instars, capsules of caterpillars kept in BR 400 were smaller. The weight of caterpillars and pupae, instar duration and sex ratio did not differ among the genotypes. Pupal phase duration was less in females kept in BR 400. Mortality was greater in the larval phase in ELISA and in the pupal phase in BR PAMPA.Spodoptera frugiperda, a lagarta-do-cartucho-do-milho, é uma praga polífaga de grande importância agrícola pelos danos e dificuldade de controle. A ausência de informações sobre seu impacto em milho doce motivou a comparação de sua biologia, no que tange as fases larval e pupal, entre os genótipos de milho ELISA, BR 400 (milhos doces e BR PAMPA (milho comum. Em condições de laboratório (25 ± 1ºC; 70 ± 10% UR; fotofase 12 horas, 35 lagartas foram individualizadas e alimentadas, diariamente, com seções de folhas de 3,14 cm² dos referidos genótipos, provenientes

The effect of nitrogen rate on transgenic corn Cry3Bb1 protein expression.

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Marquardt, Paul T; Krupke, Christian H; Camberato, James J; Johnson, William G

2014-05-01

Combining herbicide-resistant and Bacillus thuringiensis (Bt) traits in corn (Zea mays L.) hybrids may affect insect resistance management owing to volunteer corn. Some Bt toxins may be expressed at lower levels by nitrogen-deficient corn roots. Corn plants with sublethal levels of Bt expression could accelerate the evolution of Bt resistance in target insects. The present objective was to quantify the concentration of Bt (Cry3Bb1) in corn root tissue with varying tissue nitrogen concentrations. Expression of Cry3Bb1 toxin in root tissue was highly variable, but there were no differences in the overall concentration of Cry3Bb1 expressed between roots taken from Cry3Bb1-positive volunteer and hybrid corn plants. The nitrogen rate did affect Cry3Bb1 expression in the greenhouse, less nitrogen resulted in decreased Cry3Bb1 expression, yet this result was not documented in the field. A positive linear relationship of plant nitrogen status on Cry3Bb1 toxin expression was documented. Also, high variability in Cry3Bb1 expression is potentially problematic from an insect resistance management perspective. This variability could create a mosaic of toxin doses in the field, which does not fit into the high-dose refuge strategy and could alter predictions about the speed of evolution of resistance to Cry3Bb1 in western corn rootworm Diabrotica virgifera virgifera LeConte. © 2013 Society of Chemical Industry.

Field efficacy of Heterorhabditis bacteriophora (Nematoda: Heterorhabditidae), Metarhizium brunneum (Hypocreales: Clavicipitaceae), and chemical insecticide combinations for Diabrotica virgifera virgifera larval management

DEFF Research Database (Denmark)

Rauch, Hannes; Steinwender, Bernhardt Michael; Mayerhofer, Johanna

2017-01-01

A two-year field study using a blend of entomopathogens in conjunction with chemical insecticides was carried out to determine to which extent they affect western corn rootworm (WCR), Diabrotica virgifera virgifera, survival, maize root damages, and grain yield and to assess the potential for sid...... is considerably higher than the stipulated economic threshold under favourable growing conditions, but a systematic crop rotation is recommended as an integral part of the WCR management both as a prophylaxis and as a background for the best treatment....

Agriculture sows pests: how crop domestication, host shifts, and agricultural intensification can create insect pests from herbivores.

Science.gov (United States)

Bernal, Julio S; Medina, Raul F

2018-04-01

We argue that agriculture as practiced creates pests. We use three examples (Corn leafhopper, Dalbulus maidis; Western corn rootworm, Diabrotica virgifera virgifera; Cotton fleahopper, Pseudatomoscelis seriatus) to illustrate: firstly, how since its origins, agriculture has proven conducive to transforming selected herbivores into pests, particularly through crop domestication and spread, and agricultural intensification, and; secondly, that the herbivores that became pests were among those hosted by crop wild relatives or associates, and were pre-adapted either as whole species or component subpopulations. Two of our examples, Corn leafhopper and Western corn rootworm, illustrate how following a host shift to a domesticated host, emergent pests 'hopped' onto crops and rode expansion waves to spread far beyond the geographic ranges of their wild hosts. Western corn rootworm exemplifies how an herbivore-tolerant crop was left vulnerable when it was bred for yield and protected with insecticides. Cotton fleahopper illustrates how removing preferred wild host plants from landscapes and replacing them with crops, allows herbivores with flexible host preferences to reach pest-level populations. We conclude by arguing that in the new geological epoch we face, the Anthropocene, we can improve agriculture by looking to our past to identify and avoid missteps of early and recent farmers. Copyright © 2018 Elsevier Inc. All rights reserved.

Attraction of Diabrotica barberi Smith and Lawrence (Coleoptera: Chrysomelidae) to eugenol-baited traps in soybean

Science.gov (United States)

Diabrotica barberi Smith and Lawrence (the northern corn rootworm) is a native North American leaf beetle and a major pest of corn. However, adult D. barberi forage in various habitats outside of corn, including soybean, roadside vegetation, and prairie. Eugenol is a common floral volatile that ha...

Corn defense responses to nitrogen availability and subsequent performance and feeding preferences of beet armyworm (Lepidoptera: Noctuidae).

Science.gov (United States)

Ren, Li-Li; Hardy, Giles; Liu, Zhu-Dong; Wei, Wei; Dai, Hua-Guo

2013-06-01

Many studies have reported the effect of nitrogen (N) fertilization on plant constitutive defense responses; however, little is known about their effects on plant induced defense patterns and its consequence for insect herbivores. In our experiments, the effects of N availability on growth, nutritional quality (N content, protein/carbohydrate [P:C] ratio, modified gross energy [MGE]), and constitutive phenolics of corn, Zea mays L. were quantified. Moreover, the indirect effects of N fertilization on the beet armyworm, Spodoptera exigua Hübner through larval performance and feeding preference were examined. N fertilization increased plant growth, and depressed defense traits by increasing N content and the P:C ratio, as well as decreasing the constitutive concentration of phenolics. Subsequently, beet armyworm showed higher performance and preferentially fed on high-N corn because of its low defense traits. After beet armyworm feeding, high-N corn significantly deterred larval feeding, and had negative effects on the performance of beet armyworm through decreasing P:C ratio and increasing induced phenolics. On the contrary, there were no significant changes in P:C ratio and phenolics in low-N corn after feeding damage. Larval performance and preference were also not affected by induced compounds in low-N corn, which suggested that the expression of induced defense was dependent on N availability. The result indicates that N availability can exert a variety of bottom-up effect on plant defense patterns to influence insect population dynamics, and thereby may represent a source of variation in plant-insect interactions.

Western bean cutworm survival and the development of economic injury levels and economic thresholds in field corn.

Science.gov (United States)

Paula-Moraes, S; Hunt, T E; Wright, R J; Hein, G L; Blankenship, E E

2013-06-01

Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a native pest of dry beans (Phaseolus vulgaris L.) and corn (Zea mays L.). Historically, the western bean cutworm was distributed in the western United States, but since 1999 eastward expansion has been observed. In corn, economic impact is caused by larval ear feeding. Information on western bean cutworm biology, ecology, and economic impact is relatively limited, and the development of economic injury levels (EILs) and economic thresholds (ETs) is required for more effective management. Studies during 2008-2011, across three ecoregions of Nebraska, sought to characterize western bean cutworm survival and development of EILs and ETs. Calculations of EILs and ETs incorporated the dynamics of corn price, management cost, and pest survival. The results from the current study demonstrated low larval survival of this species (1.51-12.82%). The mean yield loss from one western bean cutworm larva per plant was 945.52 kg/ha (15.08 bu/acre), based on 74,100 plants per ha. Economic thresholds are expressed as a percentage of plants with at least one egg mass. This study is the first study that explicitly incorporates variable management costs and crop values into western bean cutworm EIL calculations, and larval survival into ET calculations.

Physiological time model for predicting adult emergence of western corn rootworm (Coleoptera: Chrysomelidae) in the Texas High Plains.

Science.gov (United States)

Stevenson, Douglass E; Michels, Gerald J; Bible, John B; Jackman, John A; Harris, Marvin K

2008-10-01

Field observations at three locations in the Texas High Plains were used to develop and validate a degree-day phenology model to predict the onset and proportional emergence of adult Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) adults. Climatic data from the Texas High Plains Potential Evapotranspiration network were used with records of cumulative proportional adult emergence to determine the functional lower developmental temperature, optimum starting date, and the sum of degree-days for phenological events from onset to 99% adult emergence. The model base temperature, 10 degrees C (50 degrees F), corresponds closely to known physiological lower limits for development. The model uses a modified Gompertz equation, y = 96.5 x exp (-(exp(6.0 - 0.00404 x (x - 4.0), where x is cumulative heat (degree-days), to predict y, cumulative proportional emergence expressed as a percentage. The model starts degree-day accumulation on the date of corn, Zea mays L., emergence, and predictions correspond closely to corn phenological stages from tasseling to black layer development. Validation shows the model predicts cumulative proportional adult emergence within a satisfactory interval of 4.5 d. The model is flexible enough to accommodate early planting, late emergence, and the effects of drought and heat stress. The model provides corn producers ample lead time to anticipate and implement adult control practices.

Developmental toxicity of two common corn pesticides to the endangered southern bell frog (Litoria raniformis)

International Nuclear Information System (INIS)

Choung, Catherine B.; Hyne, Ross V.; Mann, Reinier M.; Stevens, Mark M.; Hose, Grant C.

2011-01-01

To examine the link between corn agriculture and the observed decline of the endangered southern bell frog (SBF), the effects of two corn crop pesticides on larval growth and development were investigated. Tadpoles were exposed to terbufos sulfone (10 μg/L), a major breakdown product of the insecticide terbufos, and the herbicide atrazine (25 μg/L) individually and as a mixture until the completion of metamorphosis. Atrazine did not interact synergistically with terbufos sulfone or result in significant effects on growth and development alone, although there was some indication of accelerated metamorphosis in the pilot study. Terbufos sulfone alone and as a mixture (terbufos/atrazine) significantly slowed larval development and ultimately delayed metamorphosis. The observed developmental effects from an environmentally relevant concentration of terbufos sulfone indicates a risk posed by this persistent degradation product to the endangered SBF, which breeds and develops in the rice bays adjacent to corn fields treated with pesticides. - Highlights: → The effect of terbufos sulfone and atrazine on larval growth and development was investigated. → Terbufos sulfone alone significantly slowed development and delayed metamorphosis of tadpoles. → Atrazine had no observable effects alone nor did it interact synergistically with terbufos sulfone. → The developmental effects indicates a risk to endangered southern bell frogs in the irrigation area. → The results highlight the toxicological importance of some pesticide breakdown products. - A breakdown product of the insecticide terbufos retards development and delays metamorphosis of southern bell frog tadpoles.

Developmental toxicity of two common corn pesticides to the endangered southern bell frog (Litoria raniformis)

Energy Technology Data Exchange (ETDEWEB)

Choung, Catherine B., E-mail: Catherine.Choung@mq.edu.au [Department of Biological Sciences, Macquarie University, Sydney, NSW 2109 (Australia); Hyne, Ross V. [Ecotoxicology and Environmental Contaminants Section, Office of Environment and Heritage, PO Box 29, Lidcombe, NSW 1825 (Australia); Mann, Reinier M. [Centre for Environmental Sustainability, University of Technology - Sydney, PO Box 123, Broadway, NSW 2007 (Australia); Stevens, Mark M. [EH Graham Centre for Agricultural Innovation (Industry and Investment NSW and Charles Sturt University), Yanco Agricultural Institute, Private Mail Bag, Yanco, NSW 2703 (Australia); Hose, Grant C. [Department of Biological Sciences, Macquarie University, Sydney, NSW 2109 (Australia)

2011-10-15

To examine the link between corn agriculture and the observed decline of the endangered southern bell frog (SBF), the effects of two corn crop pesticides on larval growth and development were investigated. Tadpoles were exposed to terbufos sulfone (10 {mu}g/L), a major breakdown product of the insecticide terbufos, and the herbicide atrazine (25 {mu}g/L) individually and as a mixture until the completion of metamorphosis. Atrazine did not interact synergistically with terbufos sulfone or result in significant effects on growth and development alone, although there was some indication of accelerated metamorphosis in the pilot study. Terbufos sulfone alone and as a mixture (terbufos/atrazine) significantly slowed larval development and ultimately delayed metamorphosis. The observed developmental effects from an environmentally relevant concentration of terbufos sulfone indicates a risk posed by this persistent degradation product to the endangered SBF, which breeds and develops in the rice bays adjacent to corn fields treated with pesticides. - Highlights: > The effect of terbufos sulfone and atrazine on larval growth and development was investigated. > Terbufos sulfone alone significantly slowed development and delayed metamorphosis of tadpoles. > Atrazine had no observable effects alone nor did it interact synergistically with terbufos sulfone. > The developmental effects indicates a risk to endangered southern bell frogs in the irrigation area. > The results highlight the toxicological importance of some pesticide breakdown products. - A breakdown product of the insecticide terbufos retards development and delays metamorphosis of southern bell frog tadpoles.

Transcript expression plasticity as a response to alternative larval host plants in the speciation process of corn and rice strains of Spodoptera frugiperda.

Science.gov (United States)

Silva-Brandão, Karina Lucas; Horikoshi, Renato Jun; Bernardi, Daniel; Omoto, Celso; Figueira, Antonio; Brandão, Marcelo Mendes

2017-10-16

Our main purpose was to evaluate the expression of plastic and evolved genes involved in ecological speciation in the noctuid moth Spodoptera frugiperda, the fall armyworm (FAW); and to demonstrate how host plants might influence lineage differentiation in this polyphagous insect. FAW is an important pest of several crops worldwide, and it is differentiated into host plant-related strains, corn (CS) and rice strains (RS). RNA-Seq and transcriptome characterization were applied to evaluate unbiased genetic expression differences in larvae from the two strains, fed on primary (corn) and alternative (rice) host plants. We consider that genes that are differently regulated by the same FAW strain, as a response to different hosts, are "plastic". Otherwise, differences in gene expression between the two strains fed on the same host are considered constitutive differences. Individual performance parameters (larval and pupal weight) varied among conditions (strains vs. hosts). A total of 3657 contigs was related to plastic response, and 2395 contigs were differentially regulated in the two strains feeding on preferential and alternative hosts (constitutive contigs). Three molecular functions were present in all comparisons, both down- and up-regulated: oxidoreductase activity, metal-ion binding, and hydrolase activity. Metabolization of foreign chemicals is among the key functions involved in the phenotypic variation of FAW strains. From an agricultural perspective, high plasticity in families of detoxifying genes indicates the capacity for a rapid response to control compounds such as insecticides.

A novel interaction between plant-beneficial rhizobacteria and roots: colonization induces corn resistance against the root herbivore Diabrotica speciosa.

Science.gov (United States)

Santos, Franciele; Peñaflor, Maria Fernanda G V; Paré, Paul W; Sanches, Patrícia A; Kamiya, Aline C; Tonelli, Mateus; Nardi, Cristiane; Bento, José Mauricio S

2014-01-01

A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E)-β-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM) program for the protection of corn against the South American corn rootworm, D. speciosa, is considered.

Attraction, oviposition preferences, and olfactory responses of corn-infesting Ulidiidae (Diptera) to various host-based substrates

Science.gov (United States)

Fresh market sweet corn produced in Florida is threatened by larval damage by Euxesta stigmatias Loew, E. eluta Loew, and Chaetopsis massyla Walker (Diptera: Ulidiidae) that renders ears unmarketable. No standard lure exists for monitoring these pests. Oviposition and attraction bioassays were desig...

Susceptibility of field populations of the fall armyworm (Lepidoptera: Noctuidae) from Florida and Puerto Rico to purified Cry1F protein and corn leaf tissue containing single and pyramided Bt genes

Science.gov (United States)

Larval survival of Cry1F-susceptible (FL), -resistant (PR and Cry1F-RR), and -heterozygous (FL x PR and Cry1F-RS) populations of the fall armyworm, Spodoptera frugiperda (J.E. Smith) to purified Cry1F protein and corn leaf tissue of seven Bacillus thuringiensis (Bt) corn hybrids and five non-Bt corn...

Effectiveness of corn rootworm (Coleoptera: Chrysomelidae) areawide pest management in South Dakota.

Science.gov (United States)

French, B Wade; Chandler, Laurence D; Riedell, Walter E

2007-10-01

Diabrotica barberi Smith & Lawrence and Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) are serious pests of maize, Zea mays L. To reduce the amount of toxicants released into the environment, the Agricultural Research Service implemented a 5-yr (1997-2001) areawide pest management program in five geographic locations, including one in South Dakota. The objective was to use integrated pest management tactics to suppress adult Diabrotica populations over a broad geographic area by using aerially applied semiochemical-baited insecticides. Suppressed populations theoretically should reduce oviposition, limit larval feeding damage to maize roots, and result in fewer beetles emerging in subsequent years. We used emergence cages, sticky traps, and CRW lure traps to monitor adult D. barberi and D. v. virgifera populations. We sampled for Diabrotica eggs, and we determined damage to maize roots. We sampled in several maize fields (control) located near the areawide site. The baited insecticides were effective in reducing adult populations 1 and 2 wk after application, and most remained low for the duration of the maize growing season. Fewer beetles were captured in both sticky and lure traps in the areawide site than in the control site. With a few exceptions, egg counts, adult emergence, and maize root damage were similar between the areawide and control sites; however, maize roots had greater fresh weight in the control site. Although not all goals were accomplished, when considering the amount of toxicant released into the environment, using semiochemical-baited insecticides to suppress adult pest Diabrotica populations seems to be an effective areawide management tool.

Baby corn, green corn, and dry corn yield of corn cultivars

OpenAIRE

Castro,Renato S; Silva,Paulo Sérgio L; Cardoso,Milton J

2013-01-01

In corn, when the first female inflorescence is removed, the plant often produces new female inflorescences. This allows the first ear to be harvested as baby corn (BC) and the second as green corn (GC) or dry corn (DC), that is, mature corn. The flexibility provided by a variety of harvested products allows the grower to compete with better conditions in the markets. We evaluated BC, GC, and DC yields in corn cultivars AG 1051, AG 2060, and BRS 2020, after the first ear was harvested as BC. ...

A novel interaction between plant-beneficial rhizobacteria and roots: colonization induces corn resistance against the root herbivore Diabrotica speciosa.

Directory of Open Access Journals (Sweden)

Franciele Santos

Full Text Available A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E-β-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM program for the protection of corn against the South American corn rootworm, D. speciosa, is considered.

78 FR 48672 - FIFRA Scientific Advisory Panel; Notice of Public Meeting

Science.gov (United States)

2013-08-09

... for convenience. If difficulties arise resulting in webcasting outages, the meeting will continue as..., Corn rootworm biology and ecology, Population sampling, Bioassay techniques (to assess insect... monitoring program includes population sampling (performed randomly and in response to field damage...

Intraguild competition and enhanced survival of western bean cutworm (Lepidoptera: Noctuidae) on transgenic Cry1Ab (MON810) Bacillus thuringiensis corn.

Science.gov (United States)

Dorhout, David L; Rice, Marlin E

2010-02-01

The effect of genetically modified corn (event MON810, YieldGard Corn Borer) expressing the Bacillus thuringiensis sp. kurstaki (Berliner) (Bt) endotoxin, Cry1Ab, on the survival of western bean cutworm, Striacosta albicosta (Smith), larvae was examined during intraguild competition studies with either European corn borer, Ostrinia nubilalis (Hübner), or corn earworm, Helicoverpa zea (Boddie), larvae. Competition scenarios were constructed by using either a laboratory or field competition arena containing one of five different diets and one of 13 different larval size-by-species scenarios. The survival of western bean cutworms competing with corn earworms in the laboratory arenas on either a meridic diet or isoline corn silk diet was significantly lower (P corn earworm on a Cry1Ab-MON810 corn silk diet was significant higher (P corn borers generally did not alter the outcomes observed in the western bean cutworm and corn earworm only two-way competitions. These data suggest that Cry1Ab-MON810 corn may confer a competitive advantage to western bean cutworm larvae during intraguild competition, particularly from corn earworms, and that western bean cutworms become equal competitors only when they are of equal or larger size and the diet is Cry1Ab-MON810 corn.

Stochastic Corn Yield Response Functions to Nitrogen for Corn after Corn, Corn after Cotton, and Corn after Soybeans

OpenAIRE

Boyer, Christopher N.; Larson, James A.; Roberts, Roland K.; McClure, Angela T.; Tyler, Donald D.; Zhou, Vivian

2013-01-01

Deterministic and stochastic yield response plateau functions were estimated to determine the expected profit-maximizing nitrogen rates, yields, and net returns for corn grown after corn, cotton, and soybeans. The stochastic response functions were more appropriate than their deterministic counterparts, and the linear response stochastic plateau described the data the best. The profit-maximizing nitrogen rates were similar for corn after corn, cotton, and soybeans, but relative to corn after ...

Expressed sequence tags from larval gut of the European corn borer (Ostrinia nubilalis: Exploring candidate genes potentially involved in Bacillus thuringiensis toxicity and resistance

Directory of Open Access Journals (Sweden)

Crespo Andre LB

2009-06-01

Full Text Available Abstract Background Lepidoptera represents more than 160,000 insect species which include some of the most devastating pests of crops, forests, and stored products. However, the genomic information on lepidopteran insects is very limited. Only a few studies have focused on developing expressed sequence tag (EST libraries from the guts of lepidopteran larvae. Knowledge of the genes that are expressed in the insect gut are crucial for understanding basic physiology of food digestion, their interactions with Bacillus thuringiensis (Bt toxins, and for discovering new targets for novel toxins for use in pest management. This study analyzed the ESTs generated from the larval gut of the European corn borer (ECB, Ostrinia nubilalis, one of the most destructive pests of corn in North America and the western world. Our goals were to establish an ECB larval gut-specific EST database as a genomic resource for future research and to explore candidate genes potentially involved in insect-Bt interactions and Bt resistance in ECB. Results We constructed two cDNA libraries from the guts of the fifth-instar larvae of ECB and sequenced a total of 15,000 ESTs from these libraries. A total of 12,519 ESTs (83.4% appeared to be high quality with an average length of 656 bp. These ESTs represented 2,895 unique sequences, including 1,738 singletons and 1,157 contigs. Among the unique sequences, 62.7% encoded putative proteins that shared significant sequence similarities (E-value ≤ 10-3with the sequences available in GenBank. Our EST analysis revealed 52 candidate genes that potentially have roles in Bt toxicity and resistance. These genes encode 18 trypsin-like proteases, 18 chymotrypsin-like proteases, 13 aminopeptidases, 2 alkaline phosphatases and 1 cadherin-like protein. Comparisons of expression profiles of 41 selected candidate genes between Cry1Ab-susceptible and resistant strains of ECB by RT-PCR showed apparently decreased expressions in 2 trypsin-like and 2

A Maize Inbred Exhibits Resistance Against Western Corn Rootwoorm, Diabrotica virgifera virgifera.

Science.gov (United States)

Castano-Duque, Lina; Loades, Kenneth W; Tooker, John F; Brown, Kathleen M; Paul Williams, W; Luthe, Dawn S

2017-12-01

Insect resistance against root herbivores like the western corn rootworm (WCR, Diabrotica virgifera virgifera) is not well understood in non-transgenic maize. We studied the responses of two American maize inbreds, Mp708 and Tx601, to WCR infestation using biomechanical, molecular, biochemical analyses, and laser ablation tomography. Previous studies performed on several inbreds indicated that these two maize genotypes differed in resistance to pests including fall armyworm (Spodoptera frugiperda) and WCR. Our data confirmed that Mp708 shows resistance against WCR, and demonstrates that the resistance mechanism is based in a multi-trait phenotype that includes increased resistance to cutting in nodal roots, stable root growth during insect infestation, constitutive and induced expression of known herbivore-defense genes, including ribosomal inhibitor protein 2 (rip2), terpene synthase 23 (tps23) and maize insect resistance cysteine protease-1 (mir1), as well high constitutive levels of jasmonic acid and production of (E)-β-caryophyllene. In contrast, Tx601 is susceptible to WCR. These findings will facilitate the use of Mp708 as a model to explore the wide variety of mechanisms and traits involved in plant defense responses and resistance to herbivory by insects with several different feeding habits.

Dietary risk assessment of v-ATPase A dsRNAs on monarch butterfly larvae

Science.gov (United States)

The goal of this study is to assess the risks of RNA interference (RNAi)-based genetically engineered crops on a non-target arthropod, monarch butterfly, Danaus plexippus. We hypothesize that an insecticidal double-stranded (ds) RNA targeting western corn rootworm, Diabrotica virgifera virgifera, ha...

Potential damage costs of Diabrotica virgifera virgifera infestation in Europe - the 'no control' scenario

NARCIS (Netherlands)

Wesseler, J.H.H.; Fall, E.H.

2010-01-01

he Western Corn Rootworm (WCR or Dvv., Diabrotica virgifera virgifera Le Conte) was first detected in Europe in the early nineties in Serbia. Since then the beetle has spread to more than 15 European countries. We assess the potential damage costs of the invasive species Diabrotica virgifera

Neonate larvae of the specialist herbivore Diabrotica virgifera virgifera do not exploit the defensive volatile (E)-ß-caryophyllene in locating maize roots

Science.gov (United States)

The behavior of the neonate larvae of Diabrotica virgifera virgifera LeConte (western corn rootworm, WCR) was assessed in presence of maize root constitutively emitting (E)-ß-caryophylene (EßC). This root volatile has been shown to attract both second instar WCR and insect-killing nematodes, offerin...

[Corn.

Science.gov (United States)

Iowa History for Young People, 1993

1993-01-01

This theme issue focuses on corn. Iowa is the number one corn producing state in the United States. The featured articles in the issue concern, among other topics, Iowa children who live on farms, facts and statistics about corn, the Mesquakie Indians and corn shelling, corn hybrids, a short story, and the corn palaces of Sioux City. Activities,…

Increased Risk of Insect Injury to Corn Following Rye Cover Crop.

Science.gov (United States)

Dunbar, Mike W; O'Neal, Matthew E; Gassmann, Aaron J

2016-08-01

Decreased pest pressure is sometimes associated with more diverse agroecosystems, including the addition of a rye cover crop (Secale cereale L.). However, not all pests respond similarly to greater vegetational diversity. Polyphagous pests, such as true armyworm (Mythimna unipuncta Haworth), black cutworm (Agrotis ipsilon Hufnagel), and common stalk borer (Papaipema nebris Guenee), whose host range includes rye have the potential to cause injury to crops following a rye cover crop. The objectives of this study were to compare the abundance of early-season insect pests and injury to corn (Zea mays L.) from fields with and without a rye cover crop on commercial farms. Fields were sampled weekly to quantify adult and larval pests and feeding injury to corn plants from mid-April until corn reached V8 stage, during 2014 and 2015. Measurements within fields were collected along transects that extended perpendicularly from field edges into the interior of cornfields. Adult true armyworm and adult black cutworm were captured around all cornfields, but most lepidopteran larvae captured within cornfields were true armyworm and common stalk borer. Cornfields with a rye cover crop had significantly greater abundance of true armyworm and greater proportion of injured corn. Both true armyworm abundance and feeding injury were significantly greater in the interior of cornfields with rye. Common stalk borer abundance did not differ between cornfields with or without rye cover. Farmers planting corn following a rye cover crop should be aware of the potential for increased presence of true armyworm and for greater injury to corn. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Induction of resistance of corn plants to Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) by application of silicon and gibberellic acid.

Science.gov (United States)

Alvarenga, R; Moraes, J C; Auad, A M; Coelho, M; Nascimento, A M

2017-08-01

The aim of this study was to evaluate the effects of silicon application and administration of the phytohormone gibberellic acid on resistance of the corn plants to the fall armyworm (FAW), Spodoptera frugiperda, and their vegetative characteristics. We evaluated larval and pupal duration, survival and biomass, and adult longevity, malformation and fecundity of S. frugiperda after feeding on plant matter treated with silicon and/or gibberellic acid. The feeding preference of FAW first-instar larvae, the total leaf area consumed by the insects, and the vegetative parameters of corn plants were also evaluated. No significant differences were observed in the measured parameters of larval and pupal stages of S. frugiperda in response to silicon or gibberellic acid. In adult stage insects, the number of eggs per female was significantly reduced in insects derived from larvae fed plants treated with silicon or gibberellic acid. In a non-preference test, 48 h after release, caterpillars preferred control untreated plants and consumed less matter from plants that had received hormonal treatment (gibberellic acid). Gibberellic acid also altered the vegetative characteristics of plants, by increasing their height, shoot fresh and dry mass, and silicon content. We conclude that gibberellic acid can alter the vegetative characteristics and silicon uptake of corn plants, leading to a reduction in their consumption by S. frugiperda larvae and a decrease in female insect oviposition.

Effect of Emamectin Benzoate on Mortality, Proboscis Extension, Gustation and Reproduction of the Corn Earworm, Helicoverpa zea

OpenAIRE

López, Juan D.; Latheef, M. A.; Hoffmann, W. C.

2010-01-01

Newly emerged corn earworm adults, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) require a carbohydrate source from plant or other exudates and nectars for dispersal and reproduction. Adults actively seek and forage at feeding sites upon eclosion in the habitat of the larval host plant or during dispersal to, or colonization of, a suitable reproductive habitat. This nocturnal behavior of H. zea has potential for exploitation as a pest management strategy for suppression using an adult fee...

Soundscapes and Larval Settlement: Larval Bivalve Responses to Habitat-Associated Underwater Sounds.

Science.gov (United States)

Eggleston, David B; Lillis, Ashlee; Bohnenstiehl, DelWayne R

2016-01-01

We quantified the effects of habitat-associated sounds on the settlement response of two species of bivalves with contrasting habitat preferences: (1) Crassostrea virginicia (oyster), which prefers to settle on other oysters, and (2) Mercenaria mercenaria (clam), which settles on unstructured habitats. Oyster larval settlement in the laboratory was significantly higher when exposed to oyster reef sound compared with either off-reef or no-sound treatments. Clam larval settlement did not vary according to sound treatments. Similar to laboratory results, field experiments showed that oyster larval settlement in "larval housings" suspended above oyster reefs was significantly higher compared with off-reef sites.

Soundscapes and Larval Settlement: Characterizing the Stimulus from a Larval Perspective.

Science.gov (United States)

Lillis, Ashlee; Eggleston, David B; Bohnenstiehl, DelWayne R

2016-01-01

There is growing evidence that underwater sounds serve as a cue for the larvae of marine organisms to locate suitable settlement habitats; however, the relevant spatiotemporal scales of variability in habitat-related sounds and how this variation scales with larval settlement processes remain largely uncharacterized, particularly in estuarine habitats. Here, we provide an overview of the approaches we have developed to characterize an estuarine soundscape as it relates to larval processes, and a conceptual framework is provided for how habitat-related sounds may influence larval settlement, using oyster reef soundscapes as an example.

The U2U Corn Growing Degree Day tool: Tracking corn growth across the US Corn Belt

Directory of Open Access Journals (Sweden)

James R. Angel

2017-01-01

Full Text Available The Corn Growing Degree Day (Corn GDD tool is a web-based product that can provide decision support on a variety of issues throughout the entire growing season by integrating current conditions, historical climate data, and projections of Corn GDD through the end of the growing season based on both National Weather Service computer model forecasts and climatology. The Corn GDD tool can help agricultural producers make a variety of important decisions before and during the growing season. This support can include: assessing the risk of early and late frosts and freezes that can cause crop damage; comparing corn hybrid maturity requirements and Corn GDD projections to select seed varieties and plan activities such as spraying; guiding marketing decisions based on historical and projected Corn GDDs when considering forward crop pricing (i.e., futures market. The Corn GDD tool provides decision support for corn producers in the central U.S. corn-producing states. Survey results, web statistics, and user feedback indicate that this tool is being actively used by decision makers.

Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

Directory of Open Access Journals (Sweden)

Eliningaya J Kweka

Full Text Available Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya.A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60% and An.arabiensis (18.34%, the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024 and An. arabiensis (P = 0.002 larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001, grass cover (P≤0.001, while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001. The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001 when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002. When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines.These findings suggest that implementation of effective larval control programme should be targeted with larval

Resistance to Spodoptera frugiperda (Lepidoptera: Noctuidae) and Euxesta stigmatias (Diptera: Ulidiidae) in sweet corn derived from exogenous and endogenous genetic systems.

Science.gov (United States)

Nuessly, G S; Scully, B T; Hentz, M G; Beiriger, R; Snook, M E; Widstrom, N W

2007-12-01

Field trials using Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and Euxesta stigmatias Loew (Diptera: Ulidiidae) were conducted to evaluate resistance and potential damage interactions between these two primary corn, Zea mays L., pests against Lepidoptera-resistant corn varieties derived from both endogenous and exogenous sources. The endogenous source of resistance was maysin, a C-glycosyl flavone produced in high concentrations in varieties 'Zapalote Chico 2451' and 'Zapalote Chico sh2'. The exogenous resistance source was the Bacillus thuringiensis (Bt)11 gene that expresses Cry1A(b) insecticidal protein found in 'Attribute GSS-0966'. Damage by the two pests was compared among these resistant varieties and the susceptible 'Primetime'. Single-species tests determined that the Zapalote Chico varieties and GSS-0966 effectively reduced S. frugiperda larval damage compared with Primetime. E. stigmatias larval damage was less in the Zapalote Chico varieties than the other varieties in single-species tests. E. stigmatias damage was greater on S. frugiperda-infested versus S. frugiperda-excluded ears. Ears with S. frugiperda damage to husk, silk and kernels had greater E. stigmatias damage than ears with less S. frugiperda damage. Reversed phase high-performance liquid chromatography analysis of nonpollinated corn silk collected from field plots determined that isoorientin, maysin, and apimaysin plus 3'-methoxymaysin concentrations followed the order Zapalote Chico sh2 > Zapalote Chico 2451 > Attribute GSS-0966 = Primetime. Chlorogenic acid concentrations were greatest in Zapalote Chico 2451. The two high maysin Zapalote Chico varieties did as well against fall armyworm as the Bt-enhanced GSS-0966, and they outperformed GSS-0966 against E. stigmatias.

Influence of corn oil recovery on life-cycle greenhouse gas emissions of corn ethanol and corn oil biodiesel.

Science.gov (United States)

Wang, Zhichao; Dunn, Jennifer B; Han, Jeongwoo; Wang, Michael Q

2015-01-01

Corn oil recovery and conversion to biodiesel has been widely adopted at corn ethanol plants recently. The US EPA has projected 2.6 billion liters of biodiesel will be produced from corn oil in 2022. Corn oil biodiesel may qualify for federal renewable identification number (RIN) credits under the Renewable Fuel Standard, as well as for low greenhouse gas (GHG) emission intensity credits under California's Low Carbon Fuel Standard. Because multiple products [ethanol, biodiesel, and distiller's grain with solubles (DGS)] are produced from one feedstock (corn), however, a careful co-product treatment approach is required to accurately estimate GHG intensities of both ethanol and corn oil biodiesel and to avoid double counting of benefits associated with corn oil biodiesel production. This study develops four co-product treatment methods: (1) displacement, (2) marginal, (3) hybrid allocation, and (4) process-level energy allocation. Life-cycle GHG emissions for corn oil biodiesel were more sensitive to the choice of co-product allocation method because significantly less corn oil biodiesel is produced than corn ethanol at a dry mill. Corn ethanol life-cycle GHG emissions with the displacement, marginal, and hybrid allocation approaches are similar (61, 62, and 59 g CO2e/MJ, respectively). Although corn ethanol and DGS share upstream farming and conversion burdens in both the hybrid and process-level energy allocation methods, DGS bears a higher burden in the latter because it has lower energy content per selling price as compared to corn ethanol. As a result, with the process-level allocation approach, ethanol's life-cycle GHG emissions are lower at 46 g CO2e/MJ. Corn oil biodiesel life-cycle GHG emissions from the marginal, hybrid allocation, and process-level energy allocation methods were 14, 59, and 45 g CO2e/MJ, respectively. Sensitivity analyses were conducted to investigate the influence corn oil yield, soy biodiesel, and defatted DGS displacement credits

Updates to the Corn Ethanol Pathway and Development of an Integrated Corn and Corn Stover Ethanol Pathway in the GREET™ Model

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Wang, Michael Q. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

2014-09-01

Corn ethanol, a first-generation biofuel, is the predominant biofuel in the United States. In 2013, the total U.S. ethanol fuel production was 13.3 billion gallons, over 95% of which was produced from corn (RFA, 2014). The 2013 total renewable fuel mandate was 16.6 billion gallons according to the Energy Independence and Security Act (EISA) (U.S. Congress, 2007). Furthermore, until 2020, corn ethanol will make up a large portion of the renewable fuel volume mandated by Renewable Fuels Standard (RFS2). For the GREET1_2014 release, the corn ethanol pathway was subject to updates reflecting changes in corn agriculture and at corn ethanol plants. In the latter case, we especially focused on the incorporation of corn oil as a corn ethanol plant co-product. Section 2 covers these updates. In addition, GREET now includes options to integrate corn grain and corn stover ethanol production on the field and at the biorefinery. These changes are the focus of Section 3.

Corn

OpenAIRE

Sherwood, Brianne; Hawks, Amanda

2011-01-01

We have so much corn right now it's coming out of our ears (great pun, right?). And it's SO incredibly cheap! This is probably because the US produces 42% of the world's corn! Most of it is used for animal feed, but other uses include exporting to other countries, human food, seed, and industrial uses such as ethanol production. Because there is so much corn available here in the U.S. You can find it in a lot more foods than you think. It's in peanut butter, snack foods, soft drinks, multivit...

Impact of Corn Earworm (Lepidoptera: Noctuidae) on Field Corn (Poales: Poaceae) Yield and Grain Quality.

Science.gov (United States)

Bibb, Jenny L; Cook, Donald; Catchot, Angus; Musser, Fred; Stewart, Scott D; Leonard, Billy Rogers; Buntin, G David; Kerns, David; Allen, Tom W; Gore, Jeffrey

2018-05-28

Corn earworm, Helicoverpa zea (Boddie), commonly infests field corn, Zea mays (L.). The combination of corn plant biology, corn earworm behavior in corn ecosystems, and field corn value renders corn earworm management with foliar insecticides noneconomical. Corn technologies containing Bacillus thuringiensis (Bt) Berliner (Bacillales: Bacillaceae) were introduced that exhibit substantial efficacy against corn earworm and may reduce mycotoxin contamination in grain. The first generation Bt traits in field corn demonstrated limited activity on corn earworm feeding on grain. The pyramided corn technologies have greater cumulative protein concentrations and higher expression throughout the plant, so these corn traits should provide effective management of this pest. Additionally, reduced kernel injury may affect physical grain quality. Experiments were conducted during 2011-2012 to investigate corn earworm impact on field corn yield and grain quality. Treatments included field corn hybrids expressing the Herculex, YieldGard, and Genuity VT Triple Pro technologies. Supplemental insecticide treatments were applied every 1-2 d from silk emergence until silk senescence to create a range of injured kernels for each technology. No significant relationship between the number of corn earworm damaged kernels and yield was observed for any technology/hybrid. In these studies, corn earworm larvae did not cause enough damage to impact yield. Additionally, no consistent relationship between corn earworm damage and aflatoxin contamination was observed. Based on these data, the economic value of pyramided Bt corn traits to corn producers, in the southern United States, appears to be from management of other lepidopteran insect pests including European and southwestern corn borer.

Corn silage from corn treated with foliar fungicide and performance of Holstein cows.

Science.gov (United States)

Haerr, K J; Lopes, N M; Pereira, M N; Fellows, G M; Cardoso, F C

2015-12-01

Foliar fungicide application to corn plants is used in corn aimed for corn silage in the dairy industry, but questions regarding frequency of application and its effect on corn silage quality and feed conversion when fed to dairy cows remain prevalent. The objective of this study was to evaluate the effects of various foliar fungicide applications to corn on dry matter intake (DMI), milk production, and milk composition when fed to dairy cows. Sixty-four Holstein cows with parity 2.5±1.5, 653±80kg of body weight, and 161±51d in milk were blocked and randomly assigned to 1 of 4 corn silage treatments (total mixed ration with 35% of the dry matter as corn silage). Treatments were as follows: control (CON), corn silage with no applications of foliar fungicide; treatment 1 (1X), corn silage from corn that received 1 application of pyraclostrobin (PYR) foliar fungicide (Headline; BASF Corp.) at corn vegetative stage 5; treatment 2 (2X), corn silage from corn that received the same application as 1X plus another application of a mixture of PYR and metconazole (Headline AMP; BASF Corp.) at corn reproductive stage 1 ("silking"); and treatment 3 (3X), corn silage from corn that received the same applications as 2X as well as a third application of PYR and metconazole at reproductive stage 3 ("milky kernel"). Corn was harvested at about 32% dry matter and 3/4 milk line stage of kernel development and ensiled for 200d. Treatments were fed to cows for 5wk, with the last week being used for statistical inferences. Week -1 was used as a covariate in the statistical analysis. Dry matter intake tended to be lower for cows fed corn silage treated with fungicide than CON (23.8, 23.0, 19.5, and 21.3kg for CON, 1X, 2X, and 3X, respectively). A linear treatment effect for DMI was observed, with DMI decreasing as foliar fungicide applications increased. Treatments CON, 1X, 2X, and 3X did not differ for milk yield (34.5, 34.5, 34.2, and 34.4kg/d, respectively); however, a trend for

Turbulence-enhanced prey encounter rates in larval fish : Effects of spatial scale, larval behaviour and size

DEFF Research Database (Denmark)

Kiørboe, Thomas; MacKenzie, Brian

1995-01-01

Turbulent water motion has several effects on the feeding ecology of larval fish and other planktivorous predators. In this paper, we consider the appropriate spatial scales for estimating relative velocities between larval fish predators and their prey, and the effect that different choices of s...... in the range in which turbulent intensity has an overall positive effect on larval fish ingestion rate probability. However, experimental data to test the model predictions are lacking. We suggest that the model inputs require further empirical study....

Consumption and utilization of experimentally altered corn by southern armyworm: Iron, nitrogen, and cyclic hydroxamates.

Science.gov (United States)

Manuwoto, S; Scriber, J M

1985-11-01

The effects of differential leaf water, leaf nitrogen and cyclic hydroxamate (DIMBOA) concentrations in corn seedlings were analyzed for a polyphagous insect, the southern armyworm (Spodoptera eridania Cram.). Six different combinations of nutrients and allelochemicals [DIMBOA = 2,4-dihydroxy-7-methoxy(2H)-benzoxazin-3(4H)-one] were generated using two corn genotypes (WF9 and CI3IA) and three fertility regimes (complete nutrient, Fe-deficient, and N-deficient solutions) in the University Biotron. Poorest larval growth was observed in the low-nitrogen treatments (1.2% and 1.7% leaf N) and was the result of both low consumption rates and high metabolic costs (low efficiency of conversion of digested food, ECD). Fastest growth rates were observed forthe larvae fed leaves from the high-nitrogen treatments (4.6% and 4.4% leaf N). It is noteworthy that these treatments also contained the highest concentration of cyclic hydroxamates, which are generally believed to be the primary defensive chemicals mediating resistance against the European corn borer,Ostrinia nubilalis (Hubner). If these hydroxamates do have any deleterious or costly effects (perhaps accounting for a large portion of metabolic expenditures), the high digestibility of the leaf tissue and the increased consumption rates more than compensate, resulting in rapid growth (growth rate = consumption rate × approximate digestibility × efficiency of conversion of the digested food). These studies illustrate that variation in key nutrients and allelochemicals within a single plant species (Zea mays L.) may have significantly different effects upon various potential leaf-chewing caterpillars, such as these armyworms versus corn borers (which cannot handle the cyclic hydroxamates, even if provided with young nutritious leaf tissues).

Evaluating sampling strategies for larval cisco (Coregonus artedi)

Science.gov (United States)

Myers, J.T.; Stockwell, J.D.; Yule, D.L.; Black, J.A.

2008-01-01

To improve our ability to assess larval cisco (Coregonus artedi) populations in Lake Superior, we conducted a study to compare several sampling strategies. First, we compared density estimates of larval cisco concurrently captured in surface waters with a 2 x 1-m paired neuston net and a 0.5-m (diameter) conical net. Density estimates obtained from the two gear types were not significantly different, suggesting that the conical net is a reasonable alternative to the more cumbersome and costly neuston net. Next, we assessed the effect of tow pattern (sinusoidal versus straight tows) to examine if propeller wash affected larval density. We found no effect of propeller wash on the catchability of larval cisco. Given the availability of global positioning systems, we recommend sampling larval cisco using straight tows to simplify protocols and facilitate straightforward measurements of volume filtered. Finally, we investigated potential trends in larval cisco density estimates by sampling four time periods during the light period of a day at individual sites. Our results indicate no significant trends in larval density estimates during the day. We conclude estimates of larval cisco density across space are not confounded by time at a daily timescale. Well-designed, cost effective surveys of larval cisco abundance will help to further our understanding of this important Great Lakes forage species.

Our Mother Corn.

Science.gov (United States)

Mathers, Sherry; And Others

Developed to provide an understanding of the magnitude of the role of corn, referred to as Mother Corn in the cultures of the Seneca, Pawnee, and Hopi tribes, the student text provides information on the tribes' basic lifestyles and the way they grew and used corn in three different parts of the United States. The section on the origin of corn…

Characterisation of Culex quinquefasciatus (Diptera: Culicidae larval habitats at ground level and temporal fluctuations of larval abundance in Córdoba, Argentina

Directory of Open Access Journals (Sweden)

Marta Grech

2013-09-01

Full Text Available The aims of this study were to characterise the ground-level larval habitats of the mosquito Culex quinquefasciatus, to determine the relationships between habitat characteristics and larval abundance and to examine seasonal larval-stage variations in Córdoba city. Every two weeks for two years, 15 larval habitats (natural and artificial water bodies, including shallow wells, drains, retention ponds, canals and ditches were visited and sampled for larval mosquitoes. Data regarding the water depth, temperature and pH, permanence, the presence of aquatic vegetation and the density of collected mosquito larvae were recorded. Data on the average air temperatures and accumulated precipitation during the 15 days prior to each sampling date were also obtained. Cx. quinquefasciatus larvae were collected throughout the study period and were generally most abundant in the summer season. Generalised linear mixed models indicated the average air temperature and presence of dicotyledonous aquatic vegetation as variables that served as important predictors of larval densities. Additionally, permanent breeding sites supported high larval densities. In Córdoba city and possibly in other highly populated cities at the same latitude with the same environmental conditions, control programs should focus on permanent larval habitats with aquatic vegetation during the early spring, when the Cx. quinquefasciatus population begins to increase.

Sandeel ( Ammodytes marinus ) larval transport patterns in the North Sea from an individual-based hydrodynamic egg and larval model

DEFF Research Database (Denmark)

Christensen, Asbjørn; Jensen, Henrik; Mosegaard, Henrik

2008-01-01

We have calculated a time series of larval transport indices for the central and southern North Sea covering 1970-2004, using a combined three-dimensional hydrodynamic and individual-based modelling framework for studying sandeel (Ammodytes marinus) eggs, larval transport, and growth. The egg phase...... is modelled by a stochastic, nonlinear degree-day model describing the extended hatch period. The larval growth model is parameterized by individually back-tracking the local physical environment of larval survivors from their catch location and catch time. Using a detailed map of sandeel habitats...... analyzed, and we introduce novel a scheme to quantify direct and indirect connectivity on equal footings in terms of an interbank transit time scale....

Legumes and forage species sole or intercropped with corn in soybean-corn succession in midwestern Brazil

Directory of Open Access Journals (Sweden)

Gessí Ceccon

2013-02-01

Full Text Available The feasibility of no-tillage in the Cerrado (Savanna-like vegetation of Brazil depends on the production of sufficient above-ground crop residue, which can be increased by corn-forage intercropping. This study evaluated how above-ground crop residue production and yields of soybean and late-season corn in a soybean-corn rotation were influenced by the following crops in the year before soybean: corn (Zea mays L. intercropped with Brachiaria (Urochloa brizantha cv. Marandu, B. decumbens cv. Basilisk, B. ruziziensis, cv. comum., Panicummaximum cv. Tanzânia, sunn hemp (Crotalaria juncea L., pigeon pea [Cajanus cajan (L. Millsp]; sole corn, forage sorghum [Sorghum bicolor (L. Moench (cv. Santa Elisa], and ruzi grass. In March 2005, corn and forage species were planted in alternate rows spaced 0.90 m apart, and sole forage species were planted in rows spaced 0.45 m apart. In October 2005, the forages were killed with glyphosate and soybean was planted. After the soybean harvest in March 2006, sole late-season corn was planted in the entire experimental area. Corn grain and stover yields were unaffected by intercropping. Above-ground crop residue was greater when corn was intercropped with Tanzania grass (10.7 Mg ha-1, Marandu (10.1 Mg ha-1, and Ruzi Grass (9.8 Mg ha-1 than when corn was not intercropped (4.0 Mg ha-1. The intercropped treatments increased the percentage of soil surface covered with crop residue. Soybean and corn grain yields were higher after sole ruzi grass and intercropped ruzi grass than after other crops. The intercropping corn with Brachiaria spp. and corn with Panicum spp. increases above-ground crop residue production and maintains nutrients in the soil without reducing late-season corn yield and the viability of no-till in the midwestern region of Brazil.

21 CFR 184.1321 - Corn gluten.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn gluten. 184.1321 Section 184.1321 Food and... Substances Affirmed as GRAS § 184.1321 Corn gluten. (a) Corn gluten (CAS Reg. No. 66071-96-3), also known as corn gluten meal, is the principal protein component of corn endosperm. It consists mainly of zein and...

Development, survival and fitness performance of Helicoverpa zea (Lepidoptera: Noctuidae) in MON810 Bt field corn.

Science.gov (United States)

Horner, T A; Dively, G P; Herbert, D A

2003-06-01

Helicoverpa zea (Boddie) development, survival, and feeding injury in MON810 transgenic ears of field corn (Zea mays L.) expressing Bacillus thuringiensis variety kurstaki (Bt) Cry1Ab endotoxins were compared with non-Bt ears at four geographic locations over two growing seasons. Expression of Cry1Ab endotoxin resulted in overall reductions in the percentage of damaged ears by 33% and in the amount of kernels consumed by 60%. Bt-induced effects varied significantly among locations, partly because of the overall level and timing of H. zea infestations, condition of silk tissue at the time of egg hatch, and the possible effects of plant stress. Larvae feeding on Bt ears produced scattered, discontinuous patches of partially consumed kernels, which were arranged more linearly than the compact feeding patterns in non-Bt ears. The feeding patterns suggest that larvae in Bt ears are moving about sampling kernels more frequently than larvae in non-Bt ears. Because not all kernels express the same level of endotoxin, the spatial heterogeneity of toxin distribution within Bt ears may provide an opportunity for development of behavioral responses in H. zea to avoid toxin. MON810 corn suppressed the establishment and development of H. zea to late instars by at least 75%. This level of control is considered a moderate dose, which may increase the risk of resistance development in areas where MON810 corn is widely adopted and H. zea overwinters successfully. Sublethal effects of MON810 corn resulted in prolonged larval and prepupal development, smaller pupae, and reduced fecundity of H. zea. The moderate dose effects and the spatial heterogeneity of toxin distribution among kernels could increase the additive genetic variance for both physiological and behavioral resistance in H. zea populations. Implications of localized population suppression are discussed.

21 CFR 155.131 - Canned field corn.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned field corn. 155.131 Section 155.131 Food... Canned field corn. (a) Identity. (1) Canned field corn conforms to the definition and standard of... corn by § 155.130(a), except that the corn ingredient consists of succulent field corn or a mixture of...

Biophysical models of larval dispersal in the Benguela Current ...

African Journals Online (AJOL)

We synthesise and update results from the suite of biophysical, larval-dispersal models developed in the Benguela Current ecosystem. Biophysical models of larval dispersal use outputs of physical hydrodynamic models as inputs to individual-based models in which biological processes acting during the larval life are ...

Ethanol extraction of phytosterols from corn fiber

Science.gov (United States)

Abbas, Charles; Beery, Kyle E.; Binder, Thomas P.; Rammelsberg, Anne M.

2010-11-16

The present invention provides a process for extracting sterols from a high solids, thermochemically hydrolyzed corn fiber using ethanol as the extractant. The process includes obtaining a corn fiber slurry having a moisture content from about 20 weight percent to about 50 weight percent solids (high solids content), thermochemically processing the corn fiber slurry having high solids content of 20 to 50% to produce a hydrolyzed corn fiber slurry, dewatering the hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, washing the residual corn fiber, dewatering the washed, hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, and extracting the residual corn fiber with ethanol and separating at least one sterol.

Market-oriented ethanol and corn-trade policies can reduce climate-induced US corn price volatility

International Nuclear Information System (INIS)

Verma, Monika; Diffenbaugh, Noah; Hertel, Thomas

2014-01-01

Agriculture is closely affected by climate. Over the past decade, biofuels have emerged as another important factor shaping the agricultural sector. We ask whether the presence of the US ethanol sector can play a role in moderating increases in US corn price variability, projected to occur in response to near-term global warming. Our findings suggest that the answer to this question depends heavily on the underlying forces shaping the ethanol industry. If mandate-driven, there is little doubt that the presence of the corn-ethanol sector will exacerbate price volatility. However, if market-driven, then the emergence of the corn-ethanol sector can be a double-edged sword for corn price volatility, possibly cushioning the impact of increased climate driven supply volatility, but also inheriting volatility from the newly integrated energy markets via crude oil price fluctuations. We find that empirically the former effect dominates, reducing price volatility by 27%. In contrast, mandates on ethanol production increase future price volatility by 54% in under future climate after 2020. We also consider the potential for liberalized international corn trade to cushion corn price volatility in the US. Our results suggest that allowing corn to move freely internationally serves to reduce the impact of near-term climate change on US corn price volatility by 8%. (letter)

Market-oriented ethanol and corn-trade policies can reduce climate-induced US corn price volatility

Science.gov (United States)

Verma, Monika; Hertel, Thomas; Diffenbaugh, Noah

2014-05-01

Agriculture is closely affected by climate. Over the past decade, biofuels have emerged as another important factor shaping the agricultural sector. We ask whether the presence of the US ethanol sector can play a role in moderating increases in US corn price variability, projected to occur in response to near-term global warming. Our findings suggest that the answer to this question depends heavily on the underlying forces shaping the ethanol industry. If mandate-driven, there is little doubt that the presence of the corn-ethanol sector will exacerbate price volatility. However, if market-driven, then the emergence of the corn-ethanol sector can be a double-edged sword for corn price volatility, possibly cushioning the impact of increased climate driven supply volatility, but also inheriting volatility from the newly integrated energy markets via crude oil price fluctuations. We find that empirically the former effect dominates, reducing price volatility by 27%. In contrast, mandates on ethanol production increase future price volatility by 54% in under future climate after 2020. We also consider the potential for liberalized international corn trade to cushion corn price volatility in the US. Our results suggest that allowing corn to move freely internationally serves to reduce the impact of near-term climate change on US corn price volatility by 8%.

Time of planting and choice of maize hybrids in controlling WCR (Diabrotica virgifera virgifera Le Conte) in Serbia and Montenegro.

Science.gov (United States)

Baca, F; Videnovic, Z; Erski, P; Stankovic, R; Dobrikovic, Danica

2003-01-01

Effects of the length of growing season of maize hybrids (FAO maturity groups 400, 500, 600 and 700) and planting dates on the maize crop, as an attractive supplemental feeding for western corn rootworm (WCR) beetles and larval survival, were observed in two locations of South Banat, during a three-year (1997-1999) and a two-year period (2001 and 2002). The feeding attraction of the maize crop for WCR beetles and survival of larvae were evaluated in dependency of the variable "plant lodging". The following results were obtained: First location: A. Plant lodging over time of planting and applied insecticides. 1. Early planting: 44.2%, 77.6%, and 76.7% for FAO 400, 500 and 600, respectively. 2. Late planting: 4.7%, 14.9%, and 7.9% for FAO 400, 500 and 600, respectively. B. Plant lodging over time of planting and cropping practices: 1. Early planting without insecticide application 72.2%, and with insecticide application 7.3%. The efficacy of application of insecticide carbofurane (Furadan 350 FS, dosage 4.0 liter/ha) in larval control was 89.9%. 2. Late planting without insecticide application, plant lodging was 47.7%, and with insecticide application 8.1%. The efficacy of application of insecticide carbofurane (Furadan 350 FS, dosage 4.0 l/ha-1) in larval control was 83.0%. Early planting resulted in greater survival of larvae; hence plant lodging was 10 times greater in early than in late planting. The percentage of lodged plants indicates that the maize crop in late planting was more attractive to imagoes. Therefore, more lodged plants were observed in the treatment where late planting preceded. Second location: Plant lodging as dependent on "treatments" 1. Regular plantings: 90.7% in untreated control and 76.2% in insecticide treated variant. The efficacy of insecticide application in control of high larval population was 16.0%. 2. Replanting date: 12.2% in untreated and 4.4% in treated variant. The efficacy of insecticide in control of low larval population

Rehydration of forensically important larval Diptera specimens.

Science.gov (United States)

Sanford, Michelle R; Pechal, Jennifer L; Tomberlin, Jeffery K

2011-01-01

Established procedures for collecting and preserving evidence are essential for all forensic disciplines to be accepted in court and by the forensic community at large. Entomological evidence, such as Diptera larvae, are primarily preserved in ethanol, which can evaporate over time, resulting in the dehydration of specimens. In this study, methods used for rehydrating specimens were compared. The changes in larval specimens with respect to larval length and weight for three forensically important blow fly (Diptera: Calliphoridae) species in North America were quantified. Phormia regina (Meigen), Cochliomyia macellaria (F.), and Chrysomya rufifacies (Macquart) third-instar larvae were collected from various decomposing animals and preserved with three preservation methods (80% ethanol, 70% isopropyl alcohol, and hot-water kill then 80% ethanol). Preservative solutions were allowed to evaporate. Rehydration was attempted with either of the following: 80% ethanol, commercial trisodium phosphate substitute solution, or 0.5% trisodium phosphate solution. All three methods partially restored weight and length of specimens recorded before preservation. Analysis of variance results indicated that effects of preservation, rehydration treatment, and collection animal were different in each species. The interaction between preservative method and rehydration treatment had a significant effect on both P. regina and C. macellaria larval length and weight. In addition, there was a significant interaction effect of collection animal on larval C. macellaria measurements. No significant effect was observed in C. rufifacies larval length or weight among the preservatives or treatments. These methods could be used to establish a standard operating procedure for dealing with dehydrated larval specimens in forensic investigations.

Densification characteristics of corn cobs

Energy Technology Data Exchange (ETDEWEB)

Kaliyan, Nalladurai; Morey, R. Vance [Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108 (United States)

2010-05-15

Corn cobs are potential feedstocks for producing heat, power, fuels, and chemicals. Densification of corn cobs into briquettes/pellets would improve their bulk handling, transportation, and storage properties. In this study, densification characteristics of corn cobs were studied using a uniaxial piston-cylinder densification apparatus. With a maximum compression pressure of 150 MPa, effects of particle size (0.85 and 2.81 mm), moisture content (10 and 20% w.b.), and preheating temperature (25 and 85 C) on the density and durability of the corn cob briquettes (with diameter of about 19.0 mm) were studied. It was found that the durability (measured using ASABE tumbling can method) of corn cob briquettes made at 25 C was 0%. At both particle sizes, preheating of corn cob grinds with about 10% (w.b.) moisture content to 85 C produced briquettes with a unit density of > 1100 kg m{sup -3} and durability of about 90%. (author)

Corn in consortium with forages

Directory of Open Access Journals (Sweden)

Cássia Maria de Paula Garcia

2013-12-01

Full Text Available The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was conducted at the Fazenda de Ensino, Pesquisa e Extensão – FEPE  of the Faculdade de Engenharia - UNESP, Ilha Solteira in an Oxisol in savannah conditions and in the autumn winter of 2009. The experimental area was irrigated by a center pivot and had a history of no-tillage system for 8 years. The corn hybrid used was simple DKB 390 YG at distances of 0.90 m. The seeds of grasses were sown in 0.34 m spacing in the amount of 5 kg ha-1, they were mixed with fertilizer minutes before sowing  and placed in a compartment fertilizer seeder and fertilizers were mechanically deposited in the soil at a depth of 0.03 m. The experimental design used was a randomized block with four replications and five treatments: Panicum maximum cv. Tanzania sown during the nitrogen fertilization (CTD of the corn; Panicum maximum cv. Mombaça sown during the nitrogen fertilization (CMD of the corn; Urochloa brizantha cv. Xaraés sown during the occasion of nitrogen fertilization (CBD of the corn; Urochloa ruziziensis cv. Comumsown during the nitrogen fertilization (CRD of the corn and single corn (control. The production components of corn: plant population per hectare (PlPo, number of ears per hectare (NE ha-1, number of rows per ear (NRE, number of kernels per row on the cob (NKR, number of grain in the ear (NGE and mass of 100 grains (M100G were not influenced by consortium with forage. Comparing grain yield (GY single corn and maize intercropped with forage of the genus Panicum

21 CFR 184.1865 - Corn syrup.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn syrup. 184.1865 Section 184.1865 Food and... Substances Affirmed as GRAS § 184.1865 Corn syrup. (a) Corn syrup, commonly called “glucose sirup” or “glucose syrup,” is obtained by partial hydrolysis of corn starch with safe and suitable acids or enzymes...

7 CFR 810.401 - Definition of corn.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of corn. 810.401 Section 810.401... GRAIN United States Standards for Corn Terms Defined § 810.401 Definition of corn. Grain that consists of 50 percent or more of whole kernels of shelled dent corn and/or shelled flint corn (Zea mays L...

21 CFR 184.1262 - Corn silk and corn silk extract.

Science.gov (United States)

2010-04-01

... specific limitations: Category of food Maximum level of use in food (as served) 1 Functional use Baked... chapter 10 Do. Soft candy, § 170.3(n)(38) of this chapter 20 Do. All other food categories 4 Do. 1 Parts... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn silk and corn silk extract. 184.1262 Section...

21 CFR 137.275 - Yellow corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead of...

21 CFR 137.215 - Yellow corn flour.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is used...

Deposition of insecticides on corn silks applied at high and low spray rates for control of corn earworm

Science.gov (United States)

Corn earworm is a major pest of sweet corn, especially when grown organically. Aerial application of insecticides is important for both conventionally- and organically-grown sweet corn production as sweet corn is frequently irrigated to assure return on investment given the high production costs. ...

Asian corn borer (ACB) and non-ACB pests in GM corn (Zea mays L.) in the Philippines.

Science.gov (United States)

Afidchao, Miladis M; Musters, C J M; de Snoo, Geert R

2013-07-01

The Asian corn borer (ACB), Ostrinia furnacalis (Guenée), has become the most damaging pest in corn in south-east Asia. Corn farmers in the Philippines have incurred great yield losses in the past decades because of ACB infestation. Bacillus thuringiensis (Bt) and Bt herbicide-tolerant (BtHT) corns have been developed to reduce borer attacks worldwide. This study assessed the extent of ACB and non-ACB pest infestations in both GM and non-GM corn in Isabela Province, the Philippines. Specific aims were to reinvestigate the efficacy of Bt corn in controlling ACB, to evaluate what parts of Bt corn plants are susceptible to ACB, to monitor the potential development of ACB resistance and to evaluate whether secondary pests dominate in an ACB-free Bt corn environment. The study involved preparatory interviews with farmers, site selection, field scouting and visual inspection of 200 plants along 200 m transect lines through 198 cornfields. Bt corn can efficiently reduce the ACB pest problem and reduce borer damage by 44%, to damage levels in Bt and BtHT corn of 6.8 and 7% respectively. The leaves of Bt corn were more susceptible, while cobs of Bt corn were less affected by ACB. Non-ACB pests were common in Bt toxin-free cornfields and reduced in non-GM cornfields where ACB was abundant. No secondary pest outbreaks were found in ACB-free Bt cornfields. Bt and BtHT corn hybrids containing the Cry1Ab protein performed well in Isabela Province. Reduced cob damage by ACB on Bt fields could mean smaller economic losses even with ACB infestation. The occurrence of ACB in Bt and BtHT cornfields, although at a moderate and insignificant level, could imply the potential development of resistance to Bt toxin. © 2012 Society of Chemical Industry.

WHAT IS THE VALUE OF BT CORN?

OpenAIRE

Hurley, Terrance M.; Mitchell, Paul D.; Rice, Marlin E.

2001-01-01

A common perception is that the value of Bt corn arises from two components-Bt corn increases expected profit and reduces profit variability. This perception encourages farmers and the policy makers to add a risk benefit to estimates of the value of Bt corn to account for the variability reduction. However, a conceptual model generates a useful decomposition of the value of Bt corn and a condition determining the impact of Bt corn on profit variability. An empirical model finds that Bt corn i...

Models of prey capture in larval fish

NARCIS (Netherlands)

Drost, M.R.

1986-01-01

The food uptake of larval carp and pike is described from high speed movies with synchronous lateral and ventral views.

During prey intake by larval fishes the velocities of the created suction flow are high relative to their own size: 0.3 m/s for carp larvae of 6

21 CFR 184.1857 - Corn sugar.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn sugar. 184.1857 Section 184.1857 Food and... Substances Affirmed as GRAS § 184.1857 Corn sugar. (a) Corn sugar (C6H12O6, CAS Reg. No. 50-99-7), commonly... monohydrate form and is produced by the complete hydrolysis of corn starch with safe and suitable acids or...

THE CORN-EGG PRICE TRANSMISSION MECHANISM

OpenAIRE

Babula, Ronald A.; Bessler, David A.

1990-01-01

A vector autoregression (VAR) model of corn, farm egg, and retail egg prices is estimated and shocked with a corn price increase. Impulse responses in egg prices, t-statistics for the impulse responses, and decompositions of forecast error variance are presented. Analyses of results provide insights on the corn/egg price transmission mechanism and on how corn price shocks pulsate through the egg-related economy.

Stock-specific advection of larval walleye (Sander vitreus) in western Lake Erie: Implications for larval growth, mixing, and stock discrimination

Science.gov (United States)

Fraker, Michael E.; Anderson, Eric J.; May, Cassandra J.; Chen, Kuan-Yu; Davis, Jeremiah J.; DeVanna, Kristen M.; DuFour, Mark R.; Marschall, Elizabeth A.; Mayer, Christine M.; Miner, Jeffery G.; Pangle, Kevin L.; Pritt, Jeremy J.; Roseman, Edward F.; Tyson, Jeffrey T.; Zhao, Yingming; Ludsin, Stuart A

2015-01-01

Physical processes can generate spatiotemporal heterogeneity in habitat quality for fish and also influence the overlap of pre-recruit individuals (e.g., larvae) with high-quality habitat through hydrodynamic advection. In turn, individuals from different stocks that are produced in different spawning locations or at different times may experience dissimilar habitat conditions, which can underlie within- and among-stock variability in larval growth and survival. While such physically-mediated variation has been shown to be important in driving intra- and inter-annual patterns in recruitment in marine ecosystems, its role in governing larval advection, growth, survival, and recruitment has received less attention in large lake ecosystems such as the Laurentian Great Lakes. Herein, we used a hydrodynamic model linked to a larval walleye (Sander vitreus) individual-based model to explore how the timing and location of larval walleye emergence from several spawning sites in western Lake Erie (Maumee, Sandusky, and Detroit rivers; Ohio reef complex) can influence advection pathways and mixing among these local spawning populations (stocks), and how spatiotemporal variation in thermal habitat can influence stock-specific larval growth. While basin-wide advection patterns were fairly similar during 2011 and 2012, smaller scale advection patterns and the degree of stock mixing varied both within and between years. Additionally, differences in larval growth were evident among stocks and among cohorts within stocks which were attributed to spatiotemporal differences in water temperature. Using these findings, we discuss the value of linked physical–biological models for understanding the recruitment process and addressing fisheries management problems in the world's Great Lakes.

Sorghum seed maturity affects the weight and feeding duration of immature corn earworm, Helicoverpa zea, and fall armyworm, Spodoptera frugiperda, in the laboratory.

Science.gov (United States)

Soper, Alysha M; Whitworth, R Jeff; McCornack, Brian P

2013-01-01

Corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda J.E. Smith, are occasional pests in sorghum, Sorghum bicolor L. Moench (Poales: Poaceae), and can be economically damaging when conditions are favorable. Despite the frequent occurrence of mixed-species infestations, the quantitative data necessary for developing yield loss relationships for S. frugiperda are not available. Although these species share similar biological characteristics, it is unknown whether their damage potentials in developing grain sorghum panicles are the same. Using no-choice feeding assays in the laboratory, this study examined larval growth and feeding duration for H. zea and S. frugiperda in the absence of competition. Each species responded positively when exposed to sorghum seed in the soft-dough stage, supporting evidence for the interactions between host-quality and larval growth and development. The results of this study also confirmed the suitability of using laboratory-reared H. zea to develop sorghum yield loss estimates in the field, and provided insights into the biological responses of S. frugiperda feeding on developing sorghum seed.

Sorghum Seed Maturity Affects the Weight and Feeding Duration of Immature Corn Earworm, Helicoverpa zea, and Fall Armyworm, Spodoptera frugiperda, in the Laboratory

Science.gov (United States)

Soper, Alysha M.; Whitworth, R. Jeff; McCornack, Brian P.

2013-01-01

Corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda J.E. Smith, are occasional pests in sorghum, Sorghum bicolor L. Moench (Poales: Poaceae), and can be economically damaging when conditions are favorable. Despite the frequent occurrence of mixed-species infestations, the quantitative data necessary for developing yield loss relationships for S. frugiperda are not available. Although these species share similar biological characteristics, it is unknown whether their damage potentials in developing grain sorghum panicles are the same. Using no-choice feeding assays in the laboratory, this study examined larval growth and feeding duration for H. zea and S. frugiperda in the absence of competition. Each species responded positively when exposed to sorghum seed in the soft-dough stage, supporting evidence for the interactions between host-quality and larval growth and development. The results of this study also confirmed the suitability of using laboratory-reared H. zea to develop sorghum yield loss estimates in the field, and provided insights into the biological responses of S. frugiperda feeding on developing sorghum seed. PMID:24219328

Location Isn't Everything: Timing of Spawning Aggregations Optimizes Larval Replenishment.

Directory of Open Access Journals (Sweden)

Megan J Donahue

Full Text Available Many species of reef fishes form large spawning aggregations that are highly predictable in space and time. Prior research has suggested that aggregating fish derive fitness benefits not just from mating at high density but, also, from oceanographic features of the spatial locations where aggregations occur. Using a probabilistic biophysical model of larval dispersal coupled to a fine resolution hydrodynamic model of the Florida Straits, we develop a stochastic landscape of larval fitness. Tracking virtual larvae from release to settlement and incorporating changes in larval behavior through ontogeny, we found that larval success was sensitive to the timing of spawning. Indeed, propagules released during the observed spawning period had higher larval success rates than those released outside the observed spawning period. In contrast, larval success rates were relatively insensitive to the spatial position of the release site. In addition, minimum (rather than mean larval survival was maximized during the observed spawning period, indicating a reproductive strategy that minimizes the probability of recruitment failure. Given this landscape of larval fitness, we take an inverse optimization approach to define a biological objective function that reflects a tradeoff between the mean and variance of larval success in a temporally variable environment. Using this objective function, we suggest that the length of the spawning period can provide insight into the tradeoff between reproductive risk and reward.

Strong links between metal contamination, habitat modification and estuarine larval fish distributions

Energy Technology Data Exchange (ETDEWEB)

McKinley, Andrew C., E-mail: andrew.mckinley@hotmail.com [Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052 (Australia); Miskiewicz, Anthony [Environment and Recreation, Wollongong City Council, 41 Burelli Street, Wollongong, New South Wales 2500 (Australia); Taylor, Matthew D.; Johnston, Emma L. [Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052 (Australia)

2011-06-15

Changes to larval fish assemblages may have far reaching ecological impacts. Correlations between habitat modification, contamination and marine larval fish communities have rarely been assessed in situ. We investigated links between the large-scale distribution of stressors and larval fish assemblages in estuarine environments. Larval fish communities were sampled using a benthic sled within the inner and outer zones of three heavily modified and three relatively unmodified estuaries. Larval abundances were significantly greater in modified estuaries, and there were trends towards greater diversity in these systems. Differences in larval community composition were strongly related to sediment metal levels and reduced seagrass cover. The differences observed were driven by two abundant species, Paedogobius kimurai and Ambassis jacksoniensis, which occurred in large numbers almost exclusively in highly contaminated and pristine locations respectively. These findings suggest that contamination and habitat alteration manifest in substantial differences in the composition of estuarine larval fish assemblages. - Highlights: > We examine contamination/habitat modification impacts on larval fish. > Larvae communities differ between modified/unmodified estuaries. > Larvae are more abundant/diverse in modified areas. > Trends are strongly related to sediment metals/seagrass cover. > Larval impacts have wider ecological importance. - We describe strong links between sediment metals contamination, habitat modification and substantial differences in the composition of the estuarine larval fish assemblage.

Strong links between metal contamination, habitat modification and estuarine larval fish distributions

International Nuclear Information System (INIS)

McKinley, Andrew C.; Miskiewicz, Anthony; Taylor, Matthew D.; Johnston, Emma L.

2011-01-01

Changes to larval fish assemblages may have far reaching ecological impacts. Correlations between habitat modification, contamination and marine larval fish communities have rarely been assessed in situ. We investigated links between the large-scale distribution of stressors and larval fish assemblages in estuarine environments. Larval fish communities were sampled using a benthic sled within the inner and outer zones of three heavily modified and three relatively unmodified estuaries. Larval abundances were significantly greater in modified estuaries, and there were trends towards greater diversity in these systems. Differences in larval community composition were strongly related to sediment metal levels and reduced seagrass cover. The differences observed were driven by two abundant species, Paedogobius kimurai and Ambassis jacksoniensis, which occurred in large numbers almost exclusively in highly contaminated and pristine locations respectively. These findings suggest that contamination and habitat alteration manifest in substantial differences in the composition of estuarine larval fish assemblages. - Highlights: → We examine contamination/habitat modification impacts on larval fish. → Larvae communities differ between modified/unmodified estuaries. → Larvae are more abundant/diverse in modified areas. → Trends are strongly related to sediment metals/seagrass cover. → Larval impacts have wider ecological importance. - We describe strong links between sediment metals contamination, habitat modification and substantial differences in the composition of the estuarine larval fish assemblage.

Corned Beef: an Enigmatic Irish Dish

OpenAIRE

Mac Con Iomaire, Máirtín; Gallagher, Pádraic Óg

2011-01-01

Corned beef and cabbage, which is consumed in America in large quantities each Saint Patrick’s Day (17th March), is considered by most Americans to be the ultimate Irish dish. However, corned beef and cabbage is seldom eaten in modern day Ireland. It is widely reported that Irish immigrants replaced their beloved bacon and cabbage with corned beef and cabbage when they arrived in America, drawing on the corned beef supplied by their neighbouring Jewish butchers, but not all commentators beli...

21 CFR 137.265 - Degerminated white corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated white corn meal. 137.265 Section 137... Cereal Flours and Related Products § 137.265 Degerminated white corn meal. (a) Degerminated white corn meal, degermed white corn meal, is the food prepared by grinding cleaned white corn and removing bran...

Microscopic Analysis of Corn Fiber Using Corn Starch- and Cellulose-Specific Molecular Probes

Energy Technology Data Exchange (ETDEWEB)

Porter, S. E.; Donohoe, B. S.; Beery, K. E.; Xu, Q.; Ding, S.-Y.; Vinzant, T. B.; Abbas, C. A.; Himmel, M. E.

2007-09-01

Ethanol is the primary liquid transportation fuel produced from renewable feedstocks in the United States today. The majority of corn grain, the primary feedstock for ethanol production, has been historically processed in wet mills yielding products such as gluten feed, gluten meal, starch, and germ. Starch extracted from the grain is used to produce ethanol in saccharification and fermentation steps; however the extraction of starch is not 100% efficient. To better understand starch extraction during the wet milling process, we have developed fluorescent probes that can be used to visually localize starch and cellulose in samples using confocal microscopy. These probes are based on the binding specificities of two types of carbohydrate binding modules (CBMs), which are small substrate-specific protein domains derived from carbohydrate degrading enzymes. CBMs were fused, using molecular cloning techniques, to a green fluorescent protein (GFP) or to the red fluorescent protein DsRed (RFP). Using these engineered probes, we found that the binding of the starch-specific probe correlates with starch content in corn fiber samples. We also demonstrate that there is starch internally localized in the endosperm that may contribute to the high starch content in corn fiber. We also surprisingly found that the cellulose-specific probe did not bind to most corn fiber samples, but only to corn fiber that had been hydrolyzed using a thermochemical process that removes the residual starch and much of the hemicellulose. Our findings should be of interest to those working to increase the efficiency of the corn grain to ethanol process.

Corn Culture: A Story of Intelligent Design

Science.gov (United States)

Todd, Jude

2008-01-01

Scientists are not sure of how corn was created. There were two competing genetic theories about how corn came to be. One theory maintains that corn had been teased out of a wheatlike grass called teosinte (genus Zea), and the other contends that one now-extinct ancestor of corn had crossed with another grass, "Tripsacum," several millennia ago.…

Utilization of Different Corn Fractions by Broilers

Directory of Open Access Journals (Sweden)

SIFR Costa

2015-09-01

Full Text Available ABSTRACTThis study was conducted to evaluate the nutritional values of fractions of damaged corn. One hundred and eighty 22-d-old Cobb 500 male broilers were distributed in batteries according to a completely randomized design with six treatments of six replicates each. The treatments consisted of diets containing five corn fractions, classified as sound, fermented, insect-damaged, mold-damaged, or reference corn. The test diets consisted of 60% of reference diet + 40% of each corn fraction. Only the reference corn fraction included all the fractions at different proportions (0.8% fermented, 0.05% insect-damaged, 3.3% mold-damaged, and 95.85% sound grains. The method of total excreta collection was used to determine AMEn values and metabolizability coefficients of dry matter (MDM, crude protein (MCP, ether extract (MEE, and gross energy (MGE of the reference corn and its fractions. The density values of the corn fractions were used to calculate the correlations among the evaluated parameters. The evaluated corn fractions presented different compositions values. The insect-damaged and mold-damaged grains presented higher CP level, lower density, and MDM and MCP coefficients compared with the other fractions. However, calculated AMEn values were not significantly different (p>0.05 among corn fractions. A low correlation between density and AMEn content (r0.8 were calculated. Although the evaluated corn fractions presented different nutritional values, there were no marked differences in their utilization by broilers.

Fumonisins B1 and B2 in the corn-milling process and corn-based products, and evaluation of estimated daily intake.

Science.gov (United States)

Savi, Geovana D; Piacentini, Karim C; Marchi, Djeini; Scussel, Vildes M

2016-01-01

The distribution of fumonisins (FBs: FB1 and FB2) in the corn-milling process and in corn-based products, as well as daily intake estimates for the Brazilian population were evaluated. Among corn fractions samples, corn meal had the highest mean concentration of FB1 (1305 µg kg(-1)) and FB2 (651 µg kg(-1)) and a distribution factors of 452% and 256% in relation to corn grain, respectively. On the other hand, the distribution factor of FB1 and FB2 in corn flour was found to be 144% and 88% respectively, which demonstrates that fumonisins in this fraction were reduced compared with corn grain. As a result, almost half the corn meal samples (47%) would be non-compliant with future Brazilian regulation (2017) for fumonisins. However, corn-based products, such as corn flakes and popcorn, were in compliance with the regulation. The average probable daily intake and maximum probable daily intake of fumonisins estimated for the Santa Catarina state (Brazil) population were below the provisional maximum tolerable daily intake of 2 µg kg(-1) body weight day(-1) for all corn samples. Despite this, the adoption of practices to control the occurrence of fumonisins should be applied to the corn-milling fractions that may contain a higher concentration of this toxin, such as corn meal, often used for animal feed in Brazil.

Foraging behaviour and prey size spectra of larval herring Clupea harengus

DEFF Research Database (Denmark)

Munk, Peter

1992-01-01

size groups of larval herring Clupea harengus L. were studied when preying on 6 size groups of copepods. Larval swimming and attack behaviour changed with prey size and were related to the ratio between prey length and larval length. The effective search rate showed a maximum when prey length was about......, that the available biomass of food as a proportion of the predator biomass will not increase. In order to assess the uniformity of relative prey size spectra of herring larvae and their background in larval foraging behaviour, a set of experimental and field investigations has been carried out. In the experiments, 4...... in the biomass spectra of the environment is important to larval growth and survival....

21 CFR 137.260 - Enriched corn meals.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched corn meals. 137.260 Section 137.260 Food... Flours and Related Products § 137.260 Enriched corn meals. (a) Enriched corn meals are the foods, each of which conforms to the definition and standard of identity prescribed for a kind of corn meal by §§ 137...

Genetic diversity, classification and comparative study on the larval ...

African Journals Online (AJOL)

Genetic diversity, classification and comparative study on the larval phenotypic ... B. mori showed different performance based on larval phenotypic data. The analysis of variance regarding the studied traits showed that different strains have ...

Fact sheet: Ethanol from corn

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-05-31

This fact sheet is intended to provide an overview of the advantages of ethanol from corn, emphasizing ethanol`s contribution to environmental protection and sustainable agriculture. Ethanol, an alternative fuel used as an octane enhancer is produced through the conversion of starch to sugars by enzymes, and fermentation of these sugars to ethanol by yeast. The production process may involve wet milling or dry milling. Both these processes produce valuable by-products, in addition to ethanol and carbon dioxide. Ethanol contains about 32,000 BTU per litre. It is commonly believed that using state-of-the-art corn farming and corn processing processes, the amount of energy contained in ethanol and its by-products would be more than twice the energy required to grow and process corn into ethanol. Ethanol represents the third largest market for Ontario corn, after direct use as animal feed and wet milling for starch, corn sweetener and corn oil. The environmental consequences of using ethanol are very significant. It is estimated that a 10 per cent ethanol blend in gasoline would result in a 25 to 30 per cent decrease in carbon monoxide emissions, a 6 to 10 per cent decrease in net carbon dioxide, a slight increase in nitrous oxide emissions which, however, would still result in an overall decrease in ozone formation, since the significant reduction in carbon monoxide emissions would compensate for any slight increase in nitrous oxide. Volatile organic compounds emission would also decrease by about 7 per cent with a 10 per cent ethanol blend. High level blends could reduce VOCs production by as much as 30 per cent. 7 refs.

Diel and lunar variations in larval supply to Malindi Marine Park ...

African Journals Online (AJOL)

Understanding larval ecology and the mechanisms used in dispersal and habitat selection helps to better understand the population dynamics of coral reef communities. However, few studies have examined patterns of larval supply to reefs sites especially in the WIO region. Temporal patterns of fish larval occurrence in ...

Protein determination in single corns

International Nuclear Information System (INIS)

Knorr, J.; Schiekel, M.; Franke, W.; Focke, F.

1994-01-01

Determination of protein content in food materials is usually done by analyzing the nitrogen amount by wet chemical Kjeldahl method. An improved accuracy accompanied by smaller analyzing intervals can be achieved using nondestructive neutron activation. Analyses have been performed using 14 MeV neutrons to determine the content of N and P in single wheat corns. Irradiation parameters have been optimized to prevent serious radiation damage in grains. About 200 single corns have been investigated with total net weights ranging from 30 to 70 mg. The tested arrangement allows determination of nitrogen amount in a single corn down to 0.3 mg with an accuracy of better than 4 %. Mean nitrogen concentrations in the range from 9 to 19% per corn have been detected. (author) 5 refs.; 6 figs

Aflatoxin contamination of developing corn kernels.

Science.gov (United States)

Amer, M A

2005-01-01

Preharvest of corn and its contamination with aflatoxin is a serious problem. Some environmental and cultural factors responsible for infection and subsequent aflatoxin production were investigated in this study. Stage of growth and location of kernels on corn ears were found to be one of the important factors in the process of kernel infection with A. flavus & A. parasiticus. The results showed positive correlation between the stage of growth and kernel infection. Treatment of corn with aflatoxin reduced germination, protein and total nitrogen contents. Total and reducing soluble sugar was increase in corn kernels as response to infection. Sucrose and protein content were reduced in case of both pathogens. Shoot system length, seeding fresh weigh and seedling dry weigh was also affected. Both pathogens induced reduction of starch content. Healthy corn seedlings treated with aflatoxin solution were badly affected. Their leaves became yellow then, turned brown with further incubation. Moreover, their total chlorophyll and protein contents showed pronounced decrease. On the other hand, total phenolic compounds were increased. Histopathological studies indicated that A. flavus & A. parasiticus could colonize corn silks and invade developing kernels. Germination of A. flavus spores was occurred and hyphae spread rapidly across the silk, producing extensive growth and lateral branching. Conidiophores and conidia had formed in and on the corn silk. Temperature and relative humidity greatly influenced the growth of A. flavus & A. parasiticus and aflatoxin production.

"King Corn": Teaching the Food Crisis

Science.gov (United States)

Swinehart, Tim

2012-01-01

"King Corn" is in so many ways the story of how government food policy has entirely remade the food landscape in the United States over the last 40 years. From the massive expansion of the number of acres of corn grown across the country, to the ever-increasing ways that corn is incorporated into the food production process, to the…

File list: His.Lar.50.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.Lar.50.AllAg.Larval_brain dm3 Histone Larvae Larval brain SRX1426943,SRX1426945... http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/His.Lar.50.AllAg.Larval_brain.bed ...

File list: His.Lar.10.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.Lar.10.AllAg.Larval_brain dm3 Histone Larvae Larval brain SRX1426945,SRX1426943... http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/His.Lar.10.AllAg.Larval_brain.bed ...

File list: His.Lar.20.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.Lar.20.AllAg.Larval_brain dm3 Histone Larvae Larval brain SRX1426943,SRX1426945... http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/His.Lar.20.AllAg.Larval_brain.bed ...

Comparison of amino acid digestibility coefficients for corn, corn gluten meal, and corn distillers dried grains with solubles (DDGS) among three different bioassays

Science.gov (United States)

The objective of this study was to determine standardized AA digestibility of corn, corn gluten meal (CGM) and three distillers dried grains with solubles (DDGS) using the precision-fed cecectomized rooster assay (PFR), the standardized ileal AA broiler chicken assay (SIAAD), and a newly developed p...

Corn Residue Use by Livestock in the United States

Directory of Open Access Journals (Sweden)

Marty R. Schmer

2017-01-01

Full Text Available Corn ( L. residue grazing or harvest provides a simple and economical practice to integrate crops and livestock, but limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA Economic Research Service surveyed producers from 19 states on corn grain and residue management practices. Total corn residue grazed or harvested was 4.87 million ha. Approximately 4.06 million ha was grazed by 11.7 million livestock (primarily cattle in 2010. The majority of grazed corn residue occurred in Nebraska (1.91 million ha, Iowa (385,000 ha, South Dakota (361,000 ha, and Kansas (344,000 ha. Average grazing days ranged from 10 to 73 d (mean = 40 d. Corn residue harvests predominantly occurred in the central and northern Corn Belt, with an estimated 2.9 Tg of corn residue harvested across the 19 states. This survey highlights the importance of corn residue for US livestock, particularly in the western Corn Belt.

Effects of arginine vasotocin and mesotocin on the activation and development of amiloride-blockable short-circuit current across larval, adult, and cultured larval bullfrog skins.

Science.gov (United States)

Takada, Makoto; Fujimaki-Aoba, Kayo; Hokari, Shigeru

2010-03-01

Amphibian skin has osmoregulatory functions, with Na(+) crossing from outside to inside. Na(+) transport can be measured as the short-circuit current (SCC). We investigated the short-term and long-term effects of arginine vasotocin (AVT) and mesotocin (MT) (which modulate Na(+) transport) on the activation and development of an amiloride-blockable SCC (adult-type feature) in larval, adult, and corticoid-cultured larval bullfrog skins. We found: (1) AVT-receptor (AVT-R) and MT-receptor (MT-R) mRNAs could be detected in both larval and adult skins, (2) in the short term (within 60 min), the larval SCC (amiloride-stimulated SCC) was increased by AVT, forskolin, and MT, suggesting that AVT and MT did not activate the inactive ENaC (epithelial sodium channel) protein thought to be expressed in larval skin, (3) in the short term (within 90 min), AVT, forskolin, and MT stimulated the adult SCC (amiloride-blockable SCC), (4) AVT and MT increased both the larval and adult SCC via receptors insensitive to OPC-21268 (an antagonist of the V(1)-type receptor), OPC-31260 (an antagonist of the V(2)-type receptor), and ([d(CH(2))(5),Tyr(Me)(2),Thr(4),Orn(8),des-Gly-NH (2) (9) ]VT) (an antagonist of the oxytocin receptor), (5) culturing EDTA-treated larval skin with corticoids supplemented with AVT (1 microM) or MT (1 microM) for 2 weeks (long-term effects of AVT and MT) did not alter the corticoid-induced development of an amiloride-blockable SCC (adult-type feature). AVT and MT thus have the potential to stimulate SCC though channels that are already expressed, but they may not influence the development of the amiloride-blockable SCC (an adult-type feature) in larval skin.

Performance of laying hens fed diets containing DAS-59122-7 maize grain compared with diets containing nontransgenic maize grain.

Science.gov (United States)

Jacobs, C M; Utterback, P L; Parsons, C M; Rice, D; Smith, B; Hinds, M; Liebergesell, M; Sauber, T

2008-03-01

An experiment using 216 Hy-Line W-36 pullets was conducted to evaluate transgenic maize grain containing the cry34Ab1 and cry35Ab1 genes from a Bacillus thuringiensis (Bt) strain and the phosphinothricin ace-tyltransferase (pat) gene from Streptomyces viridochromogenes. Expression of the cry34Ab1 and cry35Ab1 genes confers resistance to corn rootworms, and the pat gene confers tolerance to herbicides containing glufosinate-ammonium. Pullets (20 wk of age) were placed in cage lots (3 hens/cage, 2 cages/lot) and were randomly assigned to 1 of 3 corn-soybean meal dietary treatments (12 lots/treatment) formulated with the following maize grains: near-isogenic control (control), conventional maize, and transgenic test corn line 59122 containing event DAS-59122-7. Differences between 59122 and control group means were evaluated with statistical significance at P < 0.05. Body weight and gain, egg production, egg mass, and feed efficiency for hens fed the 59122 corn were not significantly different from the respective values for hens fed diets formulated with control maize grain. Egg component weights, Haugh unit measures, and egg weight class distribution were similar regardless of the corn source. This research indicates that performance of hens fed diets containing 59122 maize grain, as measured by egg production and egg quality, was similar to that of hens fed diets formulated with near-isogenic corn grain.

Possible causes of dry pea synergy to corn

Science.gov (United States)

Dry pea improves corn yield and tolerance to weed interference compared with soybean, spring wheat, or canola as preceding crops. To understand this synergy between dry pea and corn, we examined growth and nutrient concentration of corn following dry pea or soybean in sequence. Each corn plot was ...

Effect of length of interval between cereal rye cover crop termination and corn planting on seedling root disease and corn growth

Science.gov (United States)

Cereal rye cover crops terminated immediately before corn planting can sometimes reduce corn population, early growth, and yield. We hypothesized that cereal rye may act as a green bridge for corn pathogens and may increase corn seedling root disease. A field experiment was conducted over two years ...

Efficiency of selection methods for increased ratio of pupal-larval to adult-larval weight gains in Tribolium.

Science.gov (United States)

Campo, J L; Cobos, P

1994-01-12

Four lines of Tribolium castaneum were selected in each of three replicates for increased ratio of (pupal-larval) to (adult-larval) weight gains, using selection for increased (pupal-larval) weight gain (PL), selection for decreased (adult-larval) weight gain (AL), direct selection for the ratio (R) and linear selection index of larval, pupal and adult weights (I), respectively, for four generations. Linear index was calculated with economic weights of m(2) -m(3) , m(3) -m(1) and m(1) -m(2) , respectively, with m(1) , m(2) and m(3) being the means for larval, pupal and adult weights. Selection to increase the ratio is considered to be a method to maximize the mean response in (adult-larval) weight while controlling the response in (pupal-adult) weight, and as a form of antagonistic selection to increase the weight gain during a given age period relative to the gain at another age period. Larval, pupal and adult weights were measured at 14, 21 and 28 days after adult emergence, respectively. The selected proportion was 20 % in all lines. The response observed for the ratio differed significantly among lines (p adulto-peso de larva en Tribolium Cuatro líneas de Tribolium castaneum fueron seleccionadas en cada una de tres repeticiones para incrementar el cociente (peso de pupa-peso de larva)/(peso de adulto-peso de larva); la línea PL fue seleccionada para aumentar la diferencia (peso de pupa-pesp de larva), la línea AL fue seleccionada para disminuir la diferencia (peso de adulto-peso de larva), fa línea R fue seleccionada directamente para el cociente, y la línea I fue seleccionada por medio de un índice lineal basado en los pesos de larva, pupa y adulto, durante cuatro generaciones. El índice lineal se calculó con pesos económicos de (m(2) -m(3) ), (m(3) -m(1) ), y (m(1) -m(2) ) respectivamentee, siendo m(1) , m(2) , y m(3) los valores medios para el peso de larva, pupa y adulto. La selección para aumentar el cociente indicado es un método para maximizar

Does Bt Corn Really Produce Tougher Residues

Science.gov (United States)

Bt corn hybrids produce insecticidal proteins that are derived from a bacterium, Bacillus thuringiensis. There have been concerns that Bt corn hybrids produce residues that are relatively resistant to decomposition. We conducted four experiments that examined the decomposition of corn residues und...

Nitrogen Soil Testing for Corn in Virginia

OpenAIRE

Evanylo, Gregory K.; Alley, Marcus M., 1947-

2009-01-01

An adequate supply of plant-available nitrogen (N) is crucial for efficient corn production, and corn N requirements are greater than any other nutrient. This publication reviews the link between nitrogen and corn production, nitrogen behavior, soil testing, test procedures and recommendations.

Utilization of Different Corn Fractions by Broilers

OpenAIRE

Costa, SIFR; Stringhini, JH; Ribeiro, AML; Pontalti, G; MacManus, C

2015-01-01

ABSTRACTThis study was conducted to evaluate the nutritional values of fractions of damaged corn. One hundred and eighty 22-d-old Cobb 500 male broilers were distributed in batteries according to a completely randomized design with six treatments of six replicates each. The treatments consisted of diets containing five corn fractions, classified as sound, fermented, insect-damaged, mold-damaged, or reference corn. The test diets consisted of 60% of reference diet + 40% of each corn fraction. ...

Effects of moisture content of food waste on residue separation, larval growth and larval survival in black soldier fly bioconversion.

Science.gov (United States)

Cheng, Jack Y K; Chiu, Sam L H; Lo, Irene M C

2017-09-01

In order to foster sustainable management of food waste, innovations in food waste valorization technologies are crucial. Black soldier fly (BSF) bioconversion is an emerging technology that can turn food waste into high-protein fish feed through the use of BSF larvae. The conventional method of BSF bioconversion is to feed BSF larvae with food waste directly without any moisture adjustment. However, it was reported that difficulty has been experienced in the separation of the residue (larval excreta and undigested material) from the insect biomass due to excessive moisture. In addition to the residue separation problem, the moisture content of the food waste may also affect the growth and survival aspects of BSF larvae. This study aims to determine the most suitable moisture content of food waste that can improve residue separation as well as evaluate the effects of the moisture content of food waste on larval growth and survival. In this study, pre-consumer and post-consumer food waste with different moisture content (70%, 75% and 80%) was fed to BSF larvae in a temperature-controlled rotary drum reactor. The results show that the residue can be effectively separated from the insect biomass by sieving using a 2.36mm sieve, for both types of food waste at 70% and 75% moisture content. However, sieving of the residue was not feasible for food waste at 80% moisture content. On the other hand, reduced moisture content of food waste was found to slow down larval growth. Hence, there is a trade-off between the sieving efficiency of the residue and the larval growth rate. Furthermore, the larval survival rate was not affected by the moisture content of food waste. A high larval survival rate of at least 95% was achieved using a temperature-controlled rotary drum reactor for all treatment groups. The study provides valuable insights for the waste management industry on understanding the effects of moisture content when employing BSF bioconversion for food waste recycling

File list: ALL.Lar.50.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ALL.Lar.50.AllAg.Larval_brain dm3 All antigens Larvae Larval brain SRX1426944,SRX14...26943,SRX1426945,SRX1426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/ALL.Lar.50.AllAg.Larval_brain.bed ...

File list: ALL.Lar.20.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ALL.Lar.20.AllAg.Larval_brain dm3 All antigens Larvae Larval brain SRX1426944,SRX14...26943,SRX1426945,SRX1426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/ALL.Lar.20.AllAg.Larval_brain.bed ...

File list: ALL.Lar.05.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ALL.Lar.05.AllAg.Larval_brain dm3 All antigens Larvae Larval brain SRX1426945,SRX14...26944,SRX1426946,SRX1426943 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/ALL.Lar.05.AllAg.Larval_brain.bed ...

File list: ALL.Lar.10.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ALL.Lar.10.AllAg.Larval_brain dm3 All antigens Larvae Larval brain SRX1426945,SRX14...26944,SRX1426943,SRX1426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/ALL.Lar.10.AllAg.Larval_brain.bed ...

Pest Control in Corn and Soybeans: Weeds - Insects - Diseases.

Science.gov (United States)

Doersch, R. E.; And Others

This document gives the characteristics and application rates for herbicides used to control annual weeds in corn, annual and perennial broadleaf weeds in corn, quackgrass and yellow nutsedge in corn, and annual weeds in soybeans. It also gives insecticide use information for corn and soybeans. A brief discussion of disease control in corn and…

21 CFR 137.285 - Degerminated yellow corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265 for...

Correlated evolution between mode of larval development and habitat in muricid gastropods.

Directory of Open Access Journals (Sweden)

Paula Pappalardo

Full Text Available Larval modes of development affect evolutionary processes and influence the distribution of marine invertebrates in the ocean. The decrease in pelagic development toward higher latitudes is one of the patterns of distribution most frequently discussed in marine organisms (Thorson's rule, which has been related to increased larval mortality associated with long pelagic durations in colder waters. However, the type of substrate occupied by adults has been suggested to influence the generality of the latitudinal patterns in larval development. To help understand how the environment affects the evolution of larval types we evaluated the association between larval development and habitat using gastropods of the Muricidae family as a model group. To achieve this goal, we collected information on latitudinal distribution, sea water temperature, larval development and type of substrate occupied by adults. We constructed a molecular phylogeny for 45 species of muricids to estimate the ancestral character states and to assess the relationship between traits using comparative methods in a Bayesian framework. Our results showed high probability for a common ancestor of the muricids with nonpelagic (and nonfeeding development, that lived in hard bottoms and cold temperatures. From this ancestor, a pelagic feeding larva evolved three times, and some species shifted to warmer temperatures or sand bottoms. The evolution of larval development was not independent of habitat; the most probable evolutionary route reconstructed in the analysis of correlated evolution showed that type of larval development may change in soft bottoms but in hard bottoms this change is highly unlikely. Lower sea water temperatures were associated with nonpelagic modes of development, supporting Thorson's rule. We show how environmental pressures can favor a particular mode of larval development or transitions between larval modes and discuss the reacquisition of feeding larva in

Correlated evolution between mode of larval development and habitat in muricid gastropods.

Science.gov (United States)

Pappalardo, Paula; Rodríguez-Serrano, Enrique; Fernández, Miriam

2014-01-01

Larval modes of development affect evolutionary processes and influence the distribution of marine invertebrates in the ocean. The decrease in pelagic development toward higher latitudes is one of the patterns of distribution most frequently discussed in marine organisms (Thorson's rule), which has been related to increased larval mortality associated with long pelagic durations in colder waters. However, the type of substrate occupied by adults has been suggested to influence the generality of the latitudinal patterns in larval development. To help understand how the environment affects the evolution of larval types we evaluated the association between larval development and habitat using gastropods of the Muricidae family as a model group. To achieve this goal, we collected information on latitudinal distribution, sea water temperature, larval development and type of substrate occupied by adults. We constructed a molecular phylogeny for 45 species of muricids to estimate the ancestral character states and to assess the relationship between traits using comparative methods in a Bayesian framework. Our results showed high probability for a common ancestor of the muricids with nonpelagic (and nonfeeding) development, that lived in hard bottoms and cold temperatures. From this ancestor, a pelagic feeding larva evolved three times, and some species shifted to warmer temperatures or sand bottoms. The evolution of larval development was not independent of habitat; the most probable evolutionary route reconstructed in the analysis of correlated evolution showed that type of larval development may change in soft bottoms but in hard bottoms this change is highly unlikely. Lower sea water temperatures were associated with nonpelagic modes of development, supporting Thorson's rule. We show how environmental pressures can favor a particular mode of larval development or transitions between larval modes and discuss the reacquisition of feeding larva in muricids gastropods.

Fish larval transport in the coastal waters through ecological modelling

Digital Repository Service at National Institute of Oceanography (India)

George, G.

are as follows: (i) to find out the influence of environmental parameters on the biology of the given ecosystem (ii) to track larval transport and biological abundance in relation to environmental vari- ables (iii) to compare biological abundance and fish larval... include the following investigations: (i) analysis of satellite chlorophyll data along the southwest coastal waters of India to derive a biological calender for sardine (ii) tracking the larval survival and establish a link between food and sardine inter...

Role of serotonergic neurons in the Drosophila larval response to light

Directory of Open Access Journals (Sweden)

Campos Ana

2009-06-01

Full Text Available Abstract Background Drosophila larval locomotion consists of forward peristalsis interrupted by episodes of pausing, turning and exploratory behavior (head swinging. This behavior can be regulated by visual input as seen by light-induced increase in pausing, head swinging and direction change as well as reduction of linear speed that characterizes the larval photophobic response. During 3rd instar stage, Drosophila larvae gradually cease to be repelled by light and are photoneutral by the time they wander in search for a place to undergo metamorphosis. Thus, Drosophila larval photobehavior can be used to study control of locomotion. Results We used targeted neuronal silencing to assess the role of candidate neurons in the regulation of larval photobehavior. Inactivation of DOPA decarboxylase (Ddc neurons increases the response to light throughout larval development, including during the later stages of the 3rd instar characterized by photoneutral response. Increased response to light is characterized by increase in light-induced direction change and associated pause, and reduction of linear movement. Amongst Ddc neurons, suppression of the activity of corazonergic and serotonergic but not dopaminergic neurons increases the photophobic response observed during 3rd instar stage. Silencing of serotonergic neurons does not disrupt larval locomotion or the response to mechanical stimuli. Reduced serotonin (5-hydroxytryptamine, 5-HT signaling within serotonergic neurons recapitulates the results obtained with targeted neuronal silencing. Ablation of serotonergic cells in the ventral nerve cord (VNC does not affect the larval response to light. Similarly, disruption of serotonergic projections that contact the photoreceptor termini in the brain hemispheres does not impact the larval response to light. Finally, pan-neural over-expression of 5-HT1ADro receptors, but not of any other 5-HT receptor subtype, causes a significant decrease in the response to

21 CFR 137.280 - Bolted yellow corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted yellow corn meal. 137.280 Section 137.280... Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow corn meal conforms to the definition and standard of identity prescribed by § 137.255 for bolted white corn meal except that cleaned...

Desenvolvimento de Spodoptera frugiperda (J. E. Smith em genótipos de milho tratados com extrato acetato de etila de Trichilia pallida (Swartz Development of Spodoptera frugiperda (J. E. Smith on corn genotypes treated with ethyl acetade extract from Trichilia pallida (Swartz

Directory of Open Access Journals (Sweden)

Antonia Railda Roel

1999-07-01

Full Text Available Avaliou-se o efeito do extrato acetato de etila obtido de folhas e ramos de Trichillia pallida, (a 0,001%, sobre o desenvolvimento de Spodoptera frugiperda alimentada com folhas de quatro genótipos de milho, um suscetível, 'Piranão', e três resistentes, 'CMS 14C', 'Zapalote Chico', 'ESALQ-PB-4', à referida praga. Os parâmetros biológicos avaliados foram peso, duração e viabilidade das fases larval e pupal. Verificou-se que o extrato provocou alongamento da fase larval e redução dos pesos larval e pupal e que os genótipos resistentes não confirmaram esse comportamento pois quando comparados ao genótipo suscetível, apenas reduziram o peso pupal. Não houve interação significativa entre os fatores genótipo e extrato.The effect of the ethyl acetate extract of leaves and branches of Trichilia pallida was evaluated (at 0.001% on larvae of S. frugiperda, fed on leaves of the corn genotypes 'Zapalote Chico', 'CMS 14C' and 'ESALQ-PB-4', considered resistant to this pest, and the susceptible genotype 'Piranão'. The parameters evaluated were length, weight and viability of larval and pupal stages. The extract increased the length of the larval stage, and larval and pupal weight, while resistant genotypes only reduced the pupal weight, did however not confirm the resistant behaviour. There was no interaction between genotype and extract.

Rapid corn and soybean mapping in US Corn Belt and neighboring areas

Science.gov (United States)

Zhong, Liheng; Yu, Le; Li, Xuecao; Hu, Lina; Gong, Peng

2016-11-01

The goal of this study was to promptly map the extent of corn and soybeans early in the growing season. A classification experiment was conducted for the US Corn Belt and neighboring states, which is the most important production area of corn and soybeans in the world. To improve the timeliness of the classification algorithm, training was completely based on reference data and images from other years, circumventing the need to finish reference data collection in the current season. To account for interannual variability in crop development in the cross-year classification scenario, several innovative strategies were used. A random forest classifier was used in all tests, and MODIS surface reflectance products from the years 2008-2014 were used for training and cross-year validation. It is concluded that the fuzzy classification approach is necessary to achieve satisfactory results with R-squared ~0.9 (compared with the USDA Cropland Data Layer). The year of training data is an important factor, and it is recommended to select a year with similar crop phenology as the mapping year. With this phenology-based and cross-year-training method, in 2015 we mapped the cropping proportion of corn and soybeans around mid-August, when the two crops just reached peak growth.

BIOFUEL FROM CORN STOVER

Directory of Open Access Journals (Sweden)

Ljiljanka Tomerlin

2003-12-01

Full Text Available This paper deals with production of ethyl alcohol (biofuel from corn stover acid hydrolysate by yeasts, respectively at Pichia stipitis y-7124 and Pachysolen tannophilus y-2460 and Candida shehatae y-12856. Since moist corn stover (Hybryds 619 is proving to decomposition by phyllospheric microflora. It was (conserved spattered individually by microbicids: Busan-90, Izosan-G and formalin. In form of prismatic bales, it was left in the open air during 6 months (Octobar - March. At the beginning and after 6 months the microbiological control was carried out. The only one unspattered (control and three stover corn bals being individually spattered by microbicids were fragmented and cooked with sulfur acid. The obtained four acid hydrolysates are complex substratums, containing, apart from the sugars (about 11 g dm-3 pentosa and about 5.4 g dm-3 hexose, decomposite components as lignin, caramel sugars and uronic acids. By controlling the activity of the mentioned yeasts it was confirmed that yeasts Pichia stipitis y-7124 obtained best capability of ethyl alcohol production from corn stover acid hydrolysate at 0.23 vol. % to 0.49 vol. %.

Analysis of xanthophylls in corn by HPLC.

Science.gov (United States)

Moros, E E; Darnoko, D; Cheryan, M; Perkins, E G; Jerrell, J

2002-10-09

An HPLC method was developed using the C-30 carotenoid column to separate and identify the major xanthophylls in corn (lutein, zeaxanthin, and beta-cryptoxanthin). A photodiode array detector and a mobile phase consisting of methyl tert-butyl ether/methanol/water was used. All three xanthophylls eluted in less than 25 min. Yellow dent corn had a total xanthophyll content of 21.97 microg/g with lutein content of 15.7 microg/g, zeaxanthin content of 5.7 microg/g, and beta-cryptoxanthin of 0.57 microg/g. Commercial corn gluten meal had a 7 times higher concentration of xanthophylls (145 microg/g), and deoiled corn contained 18 microg/g, indicating that the xanthophylls are probably bound to the zein fraction of corn proteins.

21 CFR 137.255 - Bolted white corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted white corn meal. 137.255 Section 137.255... Flours and Related Products § 137.255 Bolted white corn meal. (a) Bolted white corn meal is the food prepared by so grinding and sifting cleaned white corn that: (1) Its crude fiber content is less than 1.2...

Effect of hydrolysis enzymatic process of corn using protease crude (Rhizopus oligosporus-C1) to produce corn hydrolisate rich folic acid

Science.gov (United States)

Maryati, Yati; Susilowati, Agustine; Melanie, Hakiki; Lotulung, Puspa D.

2017-11-01

Corn hydrolyzate (Zea mays L) as a functional food fortificant derived from natural folic acid has been evaluated through a hydrolysis process using protease enzyme Rhizopus oligosporus strain C1. Enzymatic hydrolysis was carried out on two types of corn; yellow and white pearl variety corn, at concentration of protease enzyme (rough) 0.025; 0.125; and 0.225% (v/w of soluble nixtamal corn protein) with a hydrolysis time of 24 h at 30 °C, and pH 5.0. The results showed that the concentration of protease enzymes can increase the folic acid to the optimum condition, from the beginning to the end of the process time. Folic acid optimization of hydrolysis results in each corn was at the concentration of protease enzyme 0.225% (v/w of soluble nixtamal corn protein) in white corn and yellow corn at 24 hours hydrolysis, with folic acid composition, 283.56 µg/mL and 412.52 µg/mL, 1.07 and 1.04 mg/mL of soluble proteins, proteolytic activity 2.09 and 2.06 U/mL, total solids of 21.74 and 17.85%, total sugars of 0.56 and 2.22 mg/mL, and reducing sugar 91.72 and 48.47 mg/mL. In this condition, the increase of optimum folic acid for white corn was 33.57% and for yellow corn was 71.60% after hydrolysis.

Compositional variability of nutrients and phytochemicals in corn after processing.

Science.gov (United States)

Prasanthi, P S; Naveena, N; Vishnuvardhana Rao, M; Bhaskarachary, K

2017-04-01

The result of various process strategies on the nutrient and phytochemical composition of corn samples were studied. Fresh and cooked baby corn, sweet corn, dent corn and industrially processed and cooked popcorn, corn grits, corn flour and corn flakes were analysed for the determination of proximate, minerals, xanthophylls and phenolic acids content. This study revealed that the proximate composition of popcorn is high compared to the other corn products analyzed while the mineral composition of these maize products showed higher concentration of magnesium, phosphorus, potassium and low concentration of calcium, manganese, zinc, iron, copper, and sodium. Popcorn was high in iron, zinc, copper, manganese, sodium, magnesium and phosphorus. The xanthophylls lutein and zeaxanthin were predominant in the dent corn and the total polyphenolic content was highest in dent corn while the phenolic acids distribution was variable in different corn products. This study showed preparation and processing brought significant reduction of xanthophylls and polyphenols.

21 CFR 573.530 - Hydrogenated corn syrup.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hydrogenated corn syrup. 573.530 Section 573.530... Additive Listing § 573.530 Hydrogenated corn syrup. (a) Identity. The product is produced by hydrogenation of corn syrup over a nickel catalyst. (b) Specifications. The product contains 70 percent...

Effect of Larval Density on Food Utilization Efficiency of Tenebrio molitor (Coleoptera: Tenebrionidae).

Science.gov (United States)

Morales-Ramos, Juan A; Rojas, M Guadalupe

2015-10-01

Crowding conditions of larvae may have a significant impact on commercial production efficiency of some insects, such as Tenebrio molitor L. (Coleoptera: Tenebrionidae). Although larval densities are known to affect developmental time and growth in T. molitor, no reports were found on the effects of crowding on food utilization. The effect of larval density on food utilization efficiency of T. molitor larvae was studied by measuring efficiency of ingested food conversion (ECI), efficiency of digested food conversion (EDC), and mg of larval weight gain per gram of food consumed (LWGpFC) at increasing larval densities (12, 24, 36, 48, 50, 62, 74, and 96 larvae per dm(2)) over four consecutive 3-wk periods. Individual larval weight gain and food consumption were negatively impacted by larval density. Similarly, ECI, ECD, and LWGpFC were negatively impacted by larval density. Larval ageing, measured as four consecutive 3-wk periods, significantly and independently impacted ECI, ECD, and LWGpFC in a negative way. General linear model analysis showed that age had a higher impact than density on food utilization parameters of T. molitor larvae. Larval growth was determined to be responsible for the age effects, as measurements of larval mass density (in grams of larvae per dm(2)) had a significant impact on food utilization parameters across ages and density treatments (in number of larvae per dm(2)). The importance of mass versus numbers per unit of area as measurements of larval density and the implications of negative effects of density on food utilization for insect biomass production are discussed. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

'Peer pressure' in larval Drosophila?

Science.gov (United States)

Niewalda, Thomas; Jeske, Ines; Michels, Birgit; Gerber, Bertram

2014-06-06

Understanding social behaviour requires a study case that is simple enough to be tractable, yet complex enough to remain interesting. Do larval Drosophila meet these requirements? In a broad sense, this question can refer to effects of the mere presence of other larvae on the behaviour of a target individual. Here we focused in a more strict sense on 'peer pressure', that is on the question of whether the behaviour of a target individual larva is affected by what a surrounding group of larvae is doing. We found that innate olfactory preference of a target individual was neither affected (i) by the level of innate olfactory preference in the surrounding group nor (ii) by the expression of learned olfactory preference in the group. Likewise, learned olfactory preference of a target individual was neither affected (iii) by the level of innate olfactory preference of the surrounding group nor (iv) by the learned olfactory preference the group was expressing. We conclude that larval Drosophila thus do not take note of specifically what surrounding larvae are doing. This implies that in a strict sense, and to the extent tested, there is no social interaction between larvae. These results validate widely used en mass approaches to the behaviour of larval Drosophila. © 2014. Published by The Company of Biologists Ltd.

Low-airflow drying of fungicide-treated shelled corn

International Nuclear Information System (INIS)

Peterson, W.H.; Benson, P.W.

1993-02-01

Approved fungicides inhibit mold growth in shelled corn and allow for longer, natural-air drying. The longer drying periods permit lower than-normal airflows and smaller power units, thus reducing electrical demands on utilities in corn-producing states. Researchers placed approximately 67 m 3 (1900 bu) of one variety of shelled corn at approximately 24% moisture in each of five equally sized storage bins. They partitioned each bin vertically and filled one half of each bin with fungicide-treated corn and one half with untreated corn. Each of four bins used a different airflow. A fifth bin used the lowest of the four airflows but was equipped to capture and use solar energy. All corn dried rapidly with resulting good quality. The percentage of damaged kernels was significantly higher for untreated than for treated corn. The energy required for the lowest airflow system was approximately one half of that required for the higher, more traditional airflows. Because of lower-than-normal airflows, the electrical demand on the utility is approximately one fourth as great as that imposed when the higher, more traditional natural-air systems are used. The 1991 corn growing and drying seasons were unusual in central Illinois, the site of the study. Both harvest and drying occurred several weeks ahead of schedule. Additional work is needed to verify that findings hold true during more-normal Midwest corn growing and drying seasons; the investigators predict that they will. It should be noted that the fungicide used in this study has not yet been approved for widespread use in drying corn

The effects of corn silk on glycaemic metabolism.

Science.gov (United States)

Guo, Jianyou; Liu, Tongjun; Han, Linna; Liu, Yongmei

2009-11-23

Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk on glycaemic metabolism. Alloxan and adrenalin induced hyperglycemic mice were used in the study. The effects of corn silk on blood glucose, glycohemoglobin (HbA1c), insulin secretion, damaged pancreatic beta-cells, hepatic glycogen and gluconeogenesis in hyperglycemic mice were studied respectively. After the mice were orally administered with corn silk extract, the blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic mice (p corn silk extract 15 days later. Also, the body weight of the alloxan-induced hyperglycemic mice was increased gradually. However, ascension of blood glucose induced by adrenalin and gluconeogenesis induced by L-alanine were not inhibited by corn silk extract treatment (p > 0.05). Although corn silk extract increased the level of hepatic glycogen in the alloxan-induced hyperglycemic mice, there was no significant difference between them and that of the control group(p > 0.05). Corn silk extract markedly reduced hyperglycemia in alloxan-induced diabetic mice. The action of corn silk extract on glycaemic metabolism is not via increasing glycogen and inhibiting gluconeogenesis but through increasing insulin level as well as recovering the injured beta-cells. The results suggest that corn silk extract may be used as a hypoglycemic food or medicine for hyperglycemic people in terms of this modern pharmacological study.

21 CFR 73.315 - Corn endosperm oil.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Corn endosperm oil. 73.315 Section 73.315 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.315 Corn endosperm oil. (a) Identity. (1) The color additive corn endosperm oil is a reddish-brown liquid composed chiefly of glycerides, fatty acids, sitosterols...

Optical crop sensor for variable-rate nitrogen fertilization in corn: II - indices of fertilizer efficiency and corn yield

Directory of Open Access Journals (Sweden)

Jardes Bragagnolo

2013-10-01

Full Text Available Generally, in tropical and subtropical agroecosystems, the efficiency of nitrogen (N fertilization is low, inducing a temporal variability of crop yield, economic losses, and environmental impacts. Variable-rate N fertilization (VRF, based on optical spectrometry crop sensors, could increase the N use efficiency (NUE. The objective of this study was to evaluate the corn grain yield and N fertilization efficiency under VRF determined by an optical sensor in comparison to the traditional single-application N fertilization (TSF. With this purpose, three experiments with no-tillage corn were carried out in the 2008/09 and 2010/11 growing seasons on a Hapludox in South Brazil, in a completely randomized design, at three different sites that were analyzed separately. The following crop properties were evaluated: aboveground dry matter production and quantity of N uptake at corn flowering, grain yield, and vegetation index determined by an N-Sensor® ALS optical sensor. Across the sites, the corn N fertilizer had a positive effect on corn N uptake, resulting in increased corn dry matter and grain yield. However, N fertilization induced lower increases of corn grain yield at site 2, where there was a severe drought during the growing period. The VRF defined by the optical crop sensor increased the apparent N recovery (NRE and agronomic efficiency of N (NAE compared to the traditional fertilizer strategy. In the average of sites 1 and 3, which were not affected by drought, VRF promoted an increase of 28.0 and 41.3 % in NAE and NRE, respectively. Despite these results, no increases in corn grain yield were observed by the use of VRF compared to TSF.

Descriptions of four larval forms of Nilodosis Kieffer from East Asia

Directory of Open Access Journals (Sweden)

Hongqu Tang

2012-10-01

Full Text Available Larval material putatively assigned to the genus Nilodosis Kieffer from Korea, China and Japan has been compared. The results show that the Japanese larval form has the club- to balloon-shaped cephalic setae S7 and S9 in common with the Korean larval form, but it can be separated from the latter by the shape of the inner mandibular teeth and the premandibular teeth. The larval forms from China (Guangdong and Yunnan apparently consist of two independent species. It is most likely that there will be more species in this genus found in Asia. Larvae are mud-sandy bottom-dwellers that can occur in the littoral of lakes and the potamal of larger rivers, up to a maximum depth of 5 meters. The specific larval characters show that it probably is a semi-psammorheophilic predator. doi: 10.5324/fn.v31i0.1406.Published online: 17 October 2012. 

Proteomics Insights: Proteins related to Larval Attachment and Metamorphosis of Marine Invertebrates

Directory of Open Access Journals (Sweden)

KONDETHIMMANAHALLI eCHANDRAMOULI

2014-10-01

Full Text Available The transition in an animal from a pelagic larval stage to a sessile benthic juvenile typically requires major morphological and behavioral changes. Larval competency, attachment and initiation of metamorphosis are thought to be regulated by intrinsic chemical signals and specific sets of proteins. However, the molecular mechanisms that regulate larval attachment and metamorphosis in marine invertebrates have yet to be fully elucidated. Despite the many challenges associated with analysis of the larvae proteome, recent proteomic technologies have been used to address specific questions in larval developmental biology. These and other molecular studies have generated substantial amount of information of the proteins and molecular pathways involved in larval attachment and metamorphosis. Furthermore, the results of these studies have shown that systematic changes in protein expression patterns and post-translational modifications (PTM are crucial for the transition from larva to juvenile. The degeneration of larval tissues is mediated by protein degradation, while the development of juvenile organs may require PTM. In terms of application, the identified proteins may serve as targets for antifouling compounds, and biomarkers for environmental stressors. In this review we highlight the strengths and limitations of proteomic tools in the context of the study of marine invertebrate larval biology.

Proteomics insights: proteins related to larval attachment and metamorphosis of marine invertebrates

KAUST Repository

Chandramouli, Kondethimmanahalli

2014-10-31

The transition in an animal from a pelagic larval stage to a sessile benthic juvenile typically requires major morphological and behavioral changes. Larval competency, attachment and initiation of metamorphosis are thought to be regulated by intrinsic chemical signals and specific sets of proteins. However, the molecular mechanisms that regulate larval attachment and metamorphosis in marine invertebrates have yet to be fully elucidated. Despite the many challenges associated with analysis of the larvae proteome, recent proteomic technologies have been used to address specific questions in larval developmental biology. These and other molecular studies have generated substantial amount of information of the proteins and molecular pathways involved in larval attachment and metamorphosis. Furthermore, the results of these studies have shown that systematic changes in protein expression patterns and post-translational modifications (PTMs) are crucial for the transition from larva to juvenile. The degeneration of larval tissues is mediated by protein degradation, while the development of juvenile organs may require PTM. In terms of application, the identified proteins may serve as targets for antifouling compounds, and biomarkers for environmental stressors. In this review we highlight the strengths and limitations of proteomic tools in the context of the study of marine invertebrate larval biology.

Proteomics insights: proteins related to larval attachment and metamorphosis of marine invertebrates

KAUST Repository

Chandramouli, Kondethimmanahalli; Qian, Pei-Yuan; Ravasi, Timothy

2014-01-01

The transition in an animal from a pelagic larval stage to a sessile benthic juvenile typically requires major morphological and behavioral changes. Larval competency, attachment and initiation of metamorphosis are thought to be regulated by intrinsic chemical signals and specific sets of proteins. However, the molecular mechanisms that regulate larval attachment and metamorphosis in marine invertebrates have yet to be fully elucidated. Despite the many challenges associated with analysis of the larvae proteome, recent proteomic technologies have been used to address specific questions in larval developmental biology. These and other molecular studies have generated substantial amount of information of the proteins and molecular pathways involved in larval attachment and metamorphosis. Furthermore, the results of these studies have shown that systematic changes in protein expression patterns and post-translational modifications (PTMs) are crucial for the transition from larva to juvenile. The degeneration of larval tissues is mediated by protein degradation, while the development of juvenile organs may require PTM. In terms of application, the identified proteins may serve as targets for antifouling compounds, and biomarkers for environmental stressors. In this review we highlight the strengths and limitations of proteomic tools in the context of the study of marine invertebrate larval biology.

Effect of hydrothermal treated corn flour addition on the quality of corn-field bean gluten-free pasta

OpenAIRE

Dib Ahlem; Wójtowicz Agnieszka; Benatallah Leila; Bouasla Abdallah; Zidoune Mohammed Nasreddine

2018-01-01

Corn semolina supplemented by field bean semolina in ratio of 2/1 (w/w) were used for obtaining protein and fiber enriched gluten-free pasta. The effect of hydrothermal treatment of corn flour on its applicability as gluten-free pasta improver was tested. A central composite design involving water hydration level and the amount of hydrothermal treated corn flour were used. Instrumental analyses of pasta (cooking loss, water absorption capacity, hydration and pasting properties, textural param...

[Anaerobic co-digestion of corn stalk and vermicompost].

Science.gov (United States)

Chen, Guang-yin; Zheng, Zheng; Zou, Xing-xing; Fang, Cai-xia; Luo, Yan

2010-02-01

The characteristics of corn stalk digested alone at different total solid (TS) loading rates and co-digestion of various proportions of corn stalk and vermicompost were investigated by batch model at 35 degrees C +/- 1 degrees C. The organic loading rates (OLRs) studied were in the range of 1.2%-6.0% TS and increasing proportions of vermicompost from 20% to 80% TS. A maximum methane yield of corn stalk digested alone was 217.60 mL/g obtained at the TS loading rate of 4.8%. However, when the TS loading rate was 6.0%, the anaerobic system was acidified and the lowest pH value was 5.10 obtained on day 4 and the biogas productivity decreased. Furthermore, co-digestion of vermicompost and corn stalk in varying proportions were investigated at constant of 6.0% TS. Co-digestion with vermicompost improved the biodegradability of corn stalk and the methane yield was improved by 4.42%-58.61%, and led to higher pH values, higher volatile fatty acids (VFAs) concentration and lower alkalinity content compared with corn stalk digested alone. The maximum biogas yield and methane yield of 410.30 mL/g and 259. 35 mL/g were obtained for 40% vermicompost and 60% corn stalk respectively. Compared with corn stalk digested alone, co-digested with vermicompost didn' t affect methane content and the fermentation type, but promoted the destruction of crystalline of cellulose and the highest destruction rate was 29.36% for 40% vermicompost and 60% corn stalk. Therefore, adding vermicompost was beneficial for the decomposition and increasing the biotransformation rate of corn stalk.

Effect of the corn breaking method on oil distribution between stillage phases of dry-grind corn ethanol production.

Science.gov (United States)

Wang, H; Wang, T; Johnson, L A; Pometto, A L

2008-11-12

The majority of fuel ethanol in the United States is produced by using the dry-grind corn ethanol process. The corn oil that is contained in the coproduct, distillers' dried grains with solubles (DDGS), can be recovered for use as a biodiesel feedstock. Oil removal will also improve the feed quality of DDGS. The most economical way to remove oil is considered to be at the centrifugation step for separating thin stillage (liquid) from coarse solids after distilling the ethanol. The more oil there is in the liquid, the more it can be recovered by centrifugation. Therefore, we studied the effects of corn preparation and grinding methods on oil distribution between liquid and solid phases. Grinding the corn to three different particle sizes, flaking, flaking and grinding, and flaking and extruding were used to break up the corn kernel before fermentation, and their effects on oil distribution between the liquid and solid phases were examined by simulating an industrial decanter centrifuge. Total oil contents were measured in the liquid and solids after centrifugation. Dry matter yield and oil partitioning in the thin stillage were highly positively correlated. Flaking slightly reduced bound fat. The flaked and then extruded corn meal released the highest amount of free oil, about 25% compared to 7% for the average of the other treatments. The freed oil from flaking, however, became nonextractable after the flaked corn was ground. Fine grinding alone had little effect on oil partitioning.

File list: InP.Lar.10.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Lar.10.AllAg.Larval_brain dm3 Input control Larvae Larval brain SRX1426944,SRX1...426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/InP.Lar.10.AllAg.Larval_brain.bed ...

File list: InP.Lar.50.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Lar.50.AllAg.Larval_brain dm3 Input control Larvae Larval brain SRX1426944,SRX1...426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/InP.Lar.50.AllAg.Larval_brain.bed ...

File list: InP.Lar.05.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Lar.05.AllAg.Larval_brain dm3 Input control Larvae Larval brain SRX1426944,SRX1...426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/InP.Lar.05.AllAg.Larval_brain.bed ...

File list: InP.Lar.20.AllAg.Larval_brain [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.Lar.20.AllAg.Larval_brain dm3 Input control Larvae Larval brain SRX1426944,SRX1...426946 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/InP.Lar.20.AllAg.Larval_brain.bed ...

Inhibitory effect of corn silk on skin pigmentation.

Science.gov (United States)

Choi, Sang Yoon; Lee, Yeonmi; Kim, Sung Soo; Ju, Hyun Min; Baek, Ji Hwoon; Park, Chul-Soo; Lee, Dong-Hyuk

2014-03-03

In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

Inhibitory Effect of Corn Silk on Skin Pigmentation

Directory of Open Access Journals (Sweden)

Sang Yoon Choi

2014-03-01

Full Text Available In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

Reduced larval feeding rate is a strong evolutionary correlate of ...

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 85; Issue 3. Reduced larval feeding rate is a strong evolutionary correlate of rapid development in Drosophila melanogaster. M. Rajamani N. Raghavendra ... Keywords. life-history evolution; development time; larval feeding rate; competition; tradeoffs; Drosophila melanogaster.

Composition of forage and grain from second-generation insect-protected corn MON 89034 is equivalent to that of conventional corn (Zea mays L.).

Science.gov (United States)

Drury, Suzanne M; Reynolds, Tracey L; Ridley, William P; Bogdanova, Natalia; Riordan, Susan; Nemeth, Margaret A; Sorbet, Roy; Trujillo, William A; Breeze, Matthew L

2008-06-25

Insect-protected corn hybrids containing Cry insecticidal proteins derived from Bacillus thuringiensis have protection from target pests and provide effective management of insect resistance. MON 89034 hybrids have been developed that produce both the Cry1A.105 and Cry2Ab2 proteins, which provide two independent modes of insecticidal action against the European corn borer ( Ostrinia nubilalis ) and other lepidopteran insect pests of corn. The composition of MON 89034 corn was compared to conventional corn by measuring proximates, fiber, and minerals in forage and by measuring proximates, fiber, amino acids, fatty acids, vitamins, minerals, antinutrients, and secondary metabolites in grain collected from 10 replicated field sites across the United States and Argentina during the 2004-2005 growing seasons. Analyses established that the forage and grain from MON 89034 are compositionally comparable to the control corn hybrid and conventional corn reference hybrids. These findings support the conclusion that MON 89034 is compositionally equivalent to conventional corn hybrids.

Effects of two stressors on amphibian larval development.

Science.gov (United States)

Stark, Karolina; Scott, David E; Tsyusko, Olga; Coughlin, Daniel P; Hinton, Thomas G

2012-05-01

In parallel with a renewed interest in nuclear power and its possible environmental impacts, a new environmental radiation protection system calls for environmental indicators of radiological stress. However, because environmental stressors seldom occur alone, this study investigated the combined effects of an ecological stressor (larval density) and an anthropogenic stressor (ionizing radiation) on amphibians. Scaphiopus holbrookii tadpoles reared at different larval densities were exposed to four low irradiation dose rates (0.13, 2.4, 21, and 222 mGy d(-1)) from (137)Cs during the sensitive period prior to and throughout metamorphosis. Body size at metamorphosis and development rate served as fitness correlates related to population dynamics. Results showed that increased larval density decreased body size but did not affect development rate. Low dose rate radiation had no impact on either endpoint. Copyright © 2012 Elsevier Inc. All rights reserved.

ELASTICITY OF CORN PRICE TRANSMISION AND ITS IMPLICATION TO FARMERS

Directory of Open Access Journals (Sweden)

Ahmad Muslim

2011-09-01

Full Text Available Corn has important roles to Indonesian economy both for staple foods and for price transmission to other products. The high domestic demand for corn compared to its domestic production has made corn imports continue to grow. This research is aimed to know the elasticity of price transmission and its implication to corn’s farmers. The results of analysis show that corn price transmission is inelastic. The coefficient shows that corn market is oligopsony under the imperfect competition market. To help the corn farmers, the government has to provide fertilizer subsidy and farm credit with low interest rates, as well as impose import tariff on corn. Keywords: Corn, Elasticity of price transmission, oligopsony, imperfect competition marketJEL classification numbers: Q00, Q12, Q18

Contributions for larval development optimization of Homarus gammarus

Directory of Open Access Journals (Sweden)

Pedro Tiago Fonseca Sá

2014-06-01

The seawater rising temperature resulted in a decrease of intermoult period in all larval development stages and at all tested temperatures, ranging from 4.77 (Z1 to 16.5 days (Z3 at 16°C, whereas at 23°C, ranged from 3:02 (Z1 and 9.75 days (Z3. The results obtained are an extremely useful guide for future optimization of protocols on larval development of H. gammarus.

The effects of corn silk on glycaemic metabolism

Directory of Open Access Journals (Sweden)

Han Linna

2009-11-01

Full Text Available Abstract Background Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk on glycaemic metabolism. Methods Alloxan and adrenalin induced hyperglycemic mice were used in the study. The effects of corn silk on blood glucose, glycohemoglobin (HbA1c, insulin secretion, damaged pancreatic β-cells, hepatic glycogen and gluconeogenesis in hyperglycemic mice were studied respectively. Results After the mice were orally administered with corn silk extract, the blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic mice (p 0.05. Although corn silk extract increased the level of hepatic glycogen in the alloxan-induced hyperglycemic mice, there was no significant difference between them and that of the control group(p > 0.05. Conclusion Corn silk extract markedly reduced hyperglycemia in alloxan-induced diabetic mice. The action of corn silk extract on glycaemic metabolism is not via increasing glycogen and inhibiting gluconeogenesis but through increasing insulin level as well as recovering the injured β-cells. The results suggest that corn silk extract may be used as a hypoglycemic food or medicine for hyperglycemic people in terms of this modern pharmacological study.

Visual responses of corn silk flies (Diptera: Ulidiidae)

Science.gov (United States)

Corn silk flies are major pests impacting fresh market sweet corn production in Florida and Georgia. Control depends solely on well-times applications of insecticides to protect corn ear development. Surveillance depends on visual inspection of ears with no effective trapping methods currently ava...

Nonrenewable energy cost of corn-ethanol in China

International Nuclear Information System (INIS)

Yang, Q.; Chen, G.Q.

2012-01-01

Nonrenewable energy cost is accounted for the believed renewable biofuel of corn-ethanol in China. By a process-based energy analysis, nonrenewable energy cost in the corn-ethanol production process incorporating agricultural crop production, industrial conversion and wastewater treatment is conservatively estimated as 1.70 times that of the ethanol energy produced, corresponding to a negative energy return in contrast to the positive ones previously reported. Nonrenewable energy cost associated with wastewater treatment usually ignored in previous researches is shown important in the energy balance. Denoting the heavy nonrenewability of the produced corn-ethanol, the calculated nonrenewable energy cost would rise to 3.64 folds when part of the nonrenewable energy cost associated with water consumption, transportation and environmental remediation is included. Due to the coal dominated nonrenewable energy structure in China, corn-ethanol processes in China are mostly a conversion of coal to ethanol. Validations and discussions are also presented to reveal policy implications against corn based ethanol as an alternative energy in long term energy security planning. - Highlights: ► Nonrenewable energy (NE) cost is conservatively accounted for corn-ethanol in China. ► Corn cultivation, ethanol conversion and wastewater treatment are included. ► NE cost is estimated as 1.70 times that of the ethanol energy produced. ► Corn-ethanol processes in China are mostly a conversion of coal to ethanol.

Fitness consequences of larval exposure to Beauveria bassiana on adults of the malaria vector Anopheles stephensi.

Science.gov (United States)

Vogels, Chantal B F; Bukhari, Tullu; Koenraadt, Constantianus J M

2014-06-01

Entomopathogenic fungi have shown to be effective in biological control of both larval and adult stages of malaria mosquitoes. However, a small fraction of mosquitoes is still able to emerge after treatment with fungus during the larval stage. It remains unclear whether fitness of these adults is affected by the treatment during the larval stage and whether they are still susceptible for another treatment during the adult stage. Therefore, we tested the effects of larval exposure to the entomopathogenic fungus Beauveria bassiana on fitness of surviving Anopheles stephensi females. Furthermore, we tested whether larval exposed females were still susceptible to re-exposure to the fungus during the adult stage. Sex ratio, survival and reproductive success were compared between non-exposed and larval exposed A. stephensi. Comparisons were also made between survival of non-exposed and larval exposed females that were re-exposed to B. bassiana during the adult stage. Larval treatment did not affect sex ratio of emerging mosquitoes. Larval exposed females that were infected died significantly faster and laid equal numbers of eggs from which equal numbers of larvae hatched, compared to non-exposed females. Larval exposed females that were uninfected had equal survival, but laid a significantly larger number of eggs from which a significantly higher number of larvae hatched, compared to non-exposed females. Larval exposed females which were re-exposed to B. bassiana during the adult stage had equal survival as females exposed only during the adult stage. Our results suggest that individual consequences for fitness of larval exposed females depended on whether a fungal infection was acquired during the larval stage. Larval exposed females remained susceptible to re-exposure with B. bassiana during the adult stage, indicating that larval and adult control of malaria mosquitoes with EF are compatible. Copyright © 2014. Published by Elsevier Inc.

Enzymatic hydrolysis of corn bran arabinoxylan

DEFF Research Database (Denmark)

Agger, Jane

as a model substrate because it represents a readily available agroindustrial side product with upgrading potentials. Corn bran originates from the wet-milling process in corn starch processing, is the outmost layers of the corn kernel and is particularly rich in pentose monosaccharides comprising the major...... in a complex and ridig cell wall structure. This thesis contains a thorough examination of the monosaccharide and structural composition of corn bran, which is used to assess and apply the relevant mono component enzyme preparations. In this way, the aim is to obtain the most effective minimal enzymatic......, especially with respect to xylose and glucose release, but vast amounts of the valuable monosaccharides are lost during this pretreatment and this is especially evident for arabinose. From a scientific point of view acid catalysed pretreatment renders the substrate in a state of disruption where assessment...

Granulomatous responses in larval taeniid infections.

Science.gov (United States)

Díaz, Á; Sagasti, C; Casaravilla, C

2018-05-01

Granulomas are responses to persistent nonliving bodies or pathogens, centrally featuring specialized macrophage forms called epithelioid and multinucleated giant cells. The larval stages of the cestode parasites of the Taeniidae family (Taenia, Echinococcus) develop for years in fixed tissue sites in mammals. In consequence, they are targets of granulomatous responses. The information on tissue responses to larval taeniids is fragmented among host and parasite species and scattered over many decades. We attempt to draw an integrated picture of these responses in solid tissues. The intensity of inflammation around live parasites spans a spectrum from minimal to high, parasite vitality correlating with low inflammation. The low end of the inflammatory spectrum features collagen capsules proximal to the parasites and moderate distal infiltration. The middle of the spectrum is dominated by classical granulomatous responses, whereas the high end features massive eosinophil invasions. Across the range of parasite species, much observational evidence suggests that eosinophils are highly effective at killing larval taeniids in solid tissues, before and during chronic granulomatous responses. The evidence available also suggests that these parasites are adapted to inhibit host granulomatous responses, in part through the exacerbation of host regulatory mechanisms including regulatory T cells and TGF-β. © 2018 John Wiley & Sons Ltd.

21 CFR 137.290 - Self-rising yellow corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising yellow corn meal. 137.290 Section 137... Cereal Flours and Related Products § 137.290 Self-rising yellow corn meal. Self-rising yellow corn meal conforms to the definition and standard of identity prescribed by § 137.270 for self-rising white corn meal...

21 CFR 137.270 - Self-rising white corn meal.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising white corn meal. 137.270 Section 137... Cereal Flours and Related Products § 137.270 Self-rising white corn meal. (a) Self-rising white corn meal is an intimate mixture of white corn meal, sodium bicarbonate, and one or both of the acid-reacting...

Quantitative analysis of allantoin in Iranian corn silk

OpenAIRE

E. Khanpour*; M. Modarresi

2017-01-01

Background and objectives: Zea mays is cultivated in different parts of Iran and corn silk is used in traditional medicine. Allantoin is one of the major compounds in corn silk. The purpose of this research was the quantitatve analysis of allantoin in corn silks belonging to several regions of Iran. Methods: The samples of corn silk were prepared from three provinces of Iran (Kermanshah, Fars and Razavi Khorasan). The dried plant materials were infused in boiling distilled water with a temper...

Detoxification of corn stover and corn starch pyrolysis liquors by ligninolytic enzymes of Phanerochaete chrysosporium.

Science.gov (United States)

Khiyami, Mohammad A; Pometto, Anthony L; Brown, Robert C

2005-04-20

Phanerochaete chrysosporium (ATCC 24725) shake flask culture with 3 mM veratryl alcohol addition on day 3 was able to grow and detoxify different concentrations of diluted corn stover (Dcs) and diluted corn starch (Dst) pyrolysis liquors [10, 25, and 50% (v/v)] in defined media. GC-MS analysis of reaction products showed a decrease and change in some compounds. In addition, the total phenolic assay with Dcs samples demonstrated a decrease in the phenolic compounds. A bioassay employing Lactobacillus casei growth and lactic acid production was developed to confirm the removal of toxic compounds from 10 and 25% (v/v) Dcs and Dst by the lignolytic enzymes, but not from 50% (v/v) Dcs and Dst. The removal did not occur when sodium azide or cycloheximide was added to Ph. chrysosporium culture media, confirming the participation of lignolytic enzymes in the detoxification process. A concentrated enzyme preparation decreased the phenolic compounds in 10% (v/v) corn stover and corn starch pyrolysis liquors to the same extent as the fungal cultures.

Corn residue utilization by livestock in the USA

Science.gov (United States)

Corn (Zea mays L.) residue grazing or harvest provides a simple and economical practice to integrate crops and livestock. Limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA-ERS surveyed producers from 19 states on corn grain ...

Production of ethanol and furfural from corn stover

Science.gov (United States)

Corn stover has potential for economical production of biofuels and value-added chemicals. The conversion of corn stover to sugars involves pretreatment and enzymatic hydrolysis. We have optimized hydrothermal, dilute H2SO4 and dilute H3PO4 pretreatments of corn stover for enzymatic saccharificati...

Effect of irradiation on sweet corn preservation

International Nuclear Information System (INIS)

Fu Junjie

2002-01-01

60 Co γ-ray was used to irradiate newly-harvested sweet corn and the results showed that the effects of irradiation on soluble solids, sucrose, starch and total sugar were not significant. The viscosity of starch decreased with the increasing of irradiation dose. The preservation duration of irradiated sweet corn was 7 days longer than that of CK, and the sweet, smell, taste of sweet corn had no abnormal change

Compositional analysis of genetically modified corn events (NK603, MON88017×MON810 and MON89034×MON88017) compared to conventional corn.

Science.gov (United States)

Rayan, Ahmed M; Abbott, Louise C

2015-06-01

Compositional analysis of genetically modified (GM) crops continues to be an important part of the overall evaluation in the safety assessment for these materials. The present study was designed to detect the genetic modifications and investigate the compositional analysis of GM corn containing traits of multiple genes (NK603, MON88017×MON810 and MON89034×MON88017) compared with non-GM corn. Values for most biochemical components assessed for the GM corn samples were similar to those of the non-GM control or were within the literature range. Significant increases were observed in protein, fat, fiber and fatty acids of the GM corn samples. The observed increases may be due to the synergistic effect of new traits introduced into corn varieties. Furthermore, SDS-PAGE analysis showed high similarity among the protein fractions of the investigated corn samples. These data indicate that GM corn samples were compositionally equivalent to, and as nutritious as, non-GM corn. Copyright © 2014 Elsevier Ltd. All rights reserved.

Renewable corn-ethanol and energy security

International Nuclear Information System (INIS)

Eaves, James

2007-01-01

Though corn-ethanol is promoted as renewable, models of the production process assume fossil fuel inputs. Moreover, ethanol is promoted as a means of increasing energy security, but there is little discussion of the dependability of its supply. This study investigates the sensibility of promoting corn-ethanol as an automobile fuel, assuming a fully renewable production process. We then use historical data to estimate the supply risk of ethanol relative to imported petroleum. We find that devoting 100% of US corn to ethanol would displace 3.5% of gasoline consumption and the annual supply of the ethanol would be inherently more risky than that of imported oil. Finally, because large temperature increases can simultaneously increase fuel demand and the cost of growing corn, the supply responses of ethanol producers to temperature-induced demand shocks would likely be weaker than those of gasoline producers. (author)

Effects of beach morphology and waves on onshore larval transport

Science.gov (United States)

Fujimura, A.; Reniers, A.; Paris, C. B.; Shanks, A.; MacMahan, J.; Morgan, S.

2015-12-01

Larvae of intertidal species grow offshore, and migrate back to the shore when they are ready to settle on their adult substrates. In order to reach the habitat, they must cross the surf zone, which is characterized as a semi-permeable barrier. This is accomplished through physical forcing (i.e., waves and current) as well as their own behavior. Two possible scenarios of onshore larval transport are proposed: Negatively buoyant larvae stay in the bottom boundary layer because of turbulence-dependent sinking behavior, and are carried toward the shore by streaming of the bottom boundary layer; positively buoyant larvae move to the shore during onshore wind events, and sink to the bottom once they encounter high turbulence (i.e., surf zone edge), where they are carried by the bottom current toward the shore (Fujimura et al. 2014). Our biophysical Lagrangian particle tracking model helps to explain how beach morphology and wave conditions affect larval distribution patterns and abundance. Model results and field observations show that larval abundance in the surf zone is higher at mildly sloped, rip-channeled beaches than at steep pocket beaches. Beach attributes are broken up to examine which and how beach configuration factors affect larval abundance. Modeling with alongshore uniform beaches with variable slopes reveal that larval populations in the surf zone are negatively correlated with beach steepness. Alongshore variability enhances onshore larval transport because of increased cross-shore water exchange by rip currents. Wave groups produce transient rip currents and enhance cross-shore exchange. Effects of other wave components, such as wave height and breaking wave rollers are also considered.

First feeding of larval herring

DEFF Research Database (Denmark)

Kiørboe, Thomas; Munk, Peter; Støttrup, Josianne

1985-01-01

The transition period from endogenous to exogenous feeding by larval herring was investigated in the laboratory for four herring stocks in order to evaluate the chances of survival at the time of fiest feeding. Observations on larval activity, feeding and growth were related to amount of yolk......, visual experience with potential prey organisms prior to first feeding and prey density. Herring larvae did not initiate exogenous feeding until around the time of yolk resorption. The timing of first feeding was not influenced by prior exposure to potential prey organisms during the yolk sac stage....... In the light of these observations, the ecological significance of the yolk sac stage is discussed. Initiation of exogenous feeding was delayed by 1-4 days at a low (7.5 nauplii .cntdot. l-1) compared to a high (120 nauplii .cntdot. l-1) prey density, but even at prey densities corresponding to the lower end...

Remotely Sensing Larval Population Dynamics of Rice Field Anophelines

Science.gov (United States)

Beck, Louisa R.; Dister, Sheri W.; Wood, Byron L.; Washino, Robert K.

1997-01-01

The primary objective of both studies was to determine if RS and GIS techniques could be used to distinguish between high and low larval-producing rice fields in California. Results of the first study suggested that early-season green-up and proximity to livestock pastures were positively correlated with high larval abundance. Based on the early-season spectral differences between high and low larval-producing fields, it appeared that canopy development and tillering influenced mosquito habitat quality. At that time, rice fields consisted of a mixture of plants and water, a combination that allowed An. freeborni females to lay eggs in partial sunlight, protected from both predators and wind. This established a population earlier in the season than in other, 'less-green' fields where tillering and plant emergence was too minimal for ovipositioning. The study also indicated the importance of the distance that a mosquito would have to fly in order to take a bloodmeal prior to ovipositing. These associations were fully explored in an expanded study two years later. The second study confirmed the positive relationship between early season canopy development and larval abundance, and also demonstrated the relationship between abundance and distance-to-pasture. The association between greenness (as measured using NDVI), distance-to-pasture, and abundance is illustrated. The second study also indicated the siginificance of the landscape context of rice fields for larval production. Fields that included opportunities for feeding and resting within the flight range of the mosquito had higher abundances than did fields that were in a homogeneous rice area.

Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

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Takken Willem

2010-01-01

Full Text Available Abstract Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density, fungus (species and concentration and environmental effects (exposure duration and food availability influence larval mortality caused by fungus, was studied. Methods Laboratory bioassays were performed on the larval stages of Anopheles gambiae and Anopheles stephensi with spores of two fungus species, Metarhizium anisopliae and Beauveria bassiana. For various larval and fungal characteristics and environmental effects the time to death was determined and survival curves established. These curves were compared by Kaplan Meier and Cox regression analyses. Results Beauveria bassiana and Metarhizium anisopliae caused high mortality of An. gambiae and An. stephensi larvae. However, Beauveria bassiana was less effective (Hazard ratio (HR Metarhizium anisopliae. Anopheles stephensi and An. gambiae were equally susceptible to each fungus. Older larvae were less likely to die than young larvae (HR Conclusions This study shows that both fungus species have potential to kill mosquitoes in the larval stage, and that mortality rate depends on fungus species itself, larval stage targeted, larval density and amount of nutrients available to the larvae. Increasing the concentration of fungal spores or reducing the exposure time to spores did not show a proportional increase and decrease in mortality rate, respectively, because the spores clumped together. As a result spores did not provide uniform coverage over space and time. It is, therefore, necessary to develop a formulation that allows the spores to spread over the water surface. Apart from formulation appropriate delivery methods are also necessary to avoid exposing non-target organisms to fungus.

Vegetative substrates used by larval northern pike in Rainy and Kabetogama Lakes, Minnesota

Science.gov (United States)

Anne L. Timm; Rodney B. Pierce

2015-01-01

Our objective was to identify characteristics of aquatic vegetative communities used as larval northern pike nursery habitat in Rainy and Kabetogama lakes, glacial shield reservoirs in northern Minnesota. Quatrefoil light traps fished at night were used to sample larval northern pike in 11 potential nursery areas. Larval northern pike were most commonly sampled among...

Evolution of increased adult longevity in Drosophila melanogaster populations selected for adaptation to larval crowding.

Science.gov (United States)

Shenoi, V N; Ali, S Z; Prasad, N G

2016-02-01

In holometabolous animals such as Drosophila melanogaster, larval crowding can affect a wide range of larval and adult traits. Adults emerging from high larval density cultures have smaller body size and increased mean life span compared to flies emerging from low larval density cultures. Therefore, adaptation to larval crowding could potentially affect adult longevity as a correlated response. We addressed this issue by studying a set of large, outbred populations of D. melanogaster, experimentally evolved for adaptation to larval crowding for 83 generations. We assayed longevity of adult flies from both selected (MCUs) and control populations (MBs) after growing them at different larval densities. We found that MCUs have evolved increased mean longevity compared to MBs at all larval densities. The interaction between selection regime and larval density was not significant, indicating that the density dependence of mean longevity had not evolved in the MCU populations. The increase in longevity in MCUs can be partially attributed to their lower rates of ageing. It is also noteworthy that reaction norm of dry body weight, a trait probably under direct selection in our populations, has indeed evolved in MCU populations. To the best of our knowledge, this is the first report of the evolution of adult longevity as a correlated response of adaptation to larval crowding. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Kauri seeds and larval somersaults

DEFF Research Database (Denmark)

Dupont, Steen Thorleif

2012-01-01

The trunk morphology of the larvae of the kauri pine (Agathis) seed infesting moth Agathiphaga is described using conventional, polarization, and scanning electron microscopy. The pine seed chamber formed by the larva is also described and commented on. The simple larval chaetotaxy includes more ...

quality of corn-field bean gluten-free pasta

Directory of Open Access Journals (Sweden)

Dib Ahlem

2018-01-01

Full Text Available Corn semolina supplemented by field bean semolina in ratio of 2/1 (w/w were used for obtaining protein and fiber enriched gluten-free pasta. The effect of hydrothermal treatment of corn flour on its applicability as gluten-free pasta improver was tested. A central composite design involving water hydration level and the amount of hydrothermal treated corn flour were used. Instrumental analyses of pasta (cooking loss, water absorption capacity, hydration and pasting properties, textural parameters and microstructure were carried out to assess the impact of experimental factors. Results showed that hydrothermal treatment of corn flour affected in different extent on pasta properties, improving cooking and textural characteristics of pasta. The optimum formulation of corn-field bean contained 7.41 g of treated corn flour and 77.26 mL of water was selected on the base of desirability function approach with value of 0.825 which showed the best pasta properties. Obtained results showed also that addition of treated flour induced significant differences (p < 0.05 in all parameters in comparison with control pasta.

Penaeid prawns in the St Lucia Lake System: Post-larval recruitment ...

African Journals Online (AJOL)

Penaeid prawns in the St Lucia Lake System: Post-larval recruitment and the bait fishery. ... Recruitment of post-larval penaeid prawns and the bait prawn fishery in the St Lucia Lake System were monitored for ... AJOL African Journals Online.

Assessment of soil attributes and crop productivity after diversification of the ubiquitous corn-soybean rotation in the northwestern U.S. Corn Belt

Science.gov (United States)

Highly specialized cash-grain production systems based upon corn-soybean rotations under tilled soil management are common in the northwestern U.S. Corn Belt. This study, initiated in 1997, was conducted to determine if diversification of this ubiquitous corn-soybean rotation would affect soil char...

Immunocytochemistry and metamorphic fate of the larval nervous system of Triphyllozoon mucronatum (Ectoprocta: Gymnolaemata: Cheilostomata)

DEFF Research Database (Denmark)

Wanninger, Andreas; Koop, Demian; Degnan, Bernard M.

2005-01-01

The development of gymnolaemate Ectoprocta includes a larval stage of either the coronate or the cyphonautes type. Herein, we provide the first description of the larval neural anatomy of a coronate larva using immunocytochemical methods. We used antibodies against the neurotransmitters serotonin...... that the larval neuroanatomy and the processes that underlie the reorganization of larval organ systems during metamorphosis may vary much more among lophotrochozoan taxa than previously thought....... and FMRFamide and followed the fate of immunoreactive cells through metamorphosis. The larval serotonergic nervous system of Triphyllozoon mucronatum consists of an apical commissure, one pair of lateral axons, a coronate nerve net, an internal nerve mesh, and one pair of axons innervating the frontal organ....... FMRFamide is only found in the larval commissure and in the lateral axons. The entire serotonergic and FMRFamidergic nervous system is lost during metamorphosis and the adult neural structures form independent of the larval ones. In the postlarval zooid, both neurotransmitters are detected in the cerebral...

Influence of continuous cropping on corn and soybean pathogens

OpenAIRE

Ranzi, Camila; Camera, Juliane Nicolodi; Deuner, Carolina Cardoso

2017-01-01

ABSTRACT The objective of this study was to evaluate the influence of two tillage programs (conventional and no-tillage) and different rotations with soybeans and corn on the occurrence of Fusarium species. The work was conducted in the experimental field and Seed Laboratory at Iowa State University. The treatments were: tillage (no-tillage and conventional tillage), crop (corn and soybeans) and three different cropping sequences for corn and soybeans, respectively. Treatment with corn: (1) t...

The larval development of the red mangrove crab Sesarma meinerti ...

African Journals Online (AJOL)

The larval stages of the red mangrove crab Sesarma meinerti de Man were reared in the laboratory. Larval development consists of five zoeal stages and one megalopa. Zoeal development lasts an average of 25 days at 25°C. The external morphology of larvae is described in detail and their relationship with larvae of.

Larval helminths in intermediate hosts

DEFF Research Database (Denmark)

Fredensborg, Brian Lund; Poulin, R

2005-01-01

Density-dependent effects on parasite fitness have been documented from adult helminths in their definitive hosts. There have, however, been no studies on the cost of sharing an intermediate host with other parasites in terms of reduced adult parasite fecundity. Even if larval parasites suffer a ...

Land usage attributed to corn ethanol production in the United States: sensitivity to technological advances in corn grain yield, ethanol conversion, and co-product utilization.

Science.gov (United States)

Mumm, Rita H; Goldsmith, Peter D; Rausch, Kent D; Stein, Hans H

2014-01-01

Although the system for producing yellow corn grain is well established in the US, its role among other biofeedstock alternatives to petroleum-based energy sources has to be balanced with its predominant purpose for food and feed as well as economics, land use, and environmental stewardship. We model land usage attributed to corn ethanol production in the US to evaluate the effects of anticipated technological change in corn grain production, ethanol processing, and livestock feeding through a multi-disciplinary approach. Seven scenarios are evaluated: four considering the impact of technological advances on corn grain production, two focused on improved efficiencies in ethanol processing, and one reflecting greater use of ethanol co-products (that is, distillers dried grains with solubles) in diets for dairy cattle, pigs, and poultry. For each scenario, land area attributed to corn ethanol production is estimated for three time horizons: 2011 (current), the time period at which the 15 billion gallon cap for corn ethanol as per the Renewable Fuel Standard is achieved, and 2026 (15 years out). Although 40.5% of corn grain was channeled to ethanol processing in 2011, only 25% of US corn acreage was attributable to ethanol when accounting for feed co-product utilization. By 2026, land area attributed to corn ethanol production is reduced to 11% to 19% depending on the corn grain yield level associated with the four corn production scenarios, considering oil replacement associated with the soybean meal substituted in livestock diets with distillers dried grains with solubles. Efficiencies in ethanol processing, although producing more ethanol per bushel of processed corn, result in less co-products and therefore less offset of corn acreage. Shifting the use of distillers dried grains with solubles in feed to dairy cattle, pigs, and poultry substantially reduces land area attributed to corn ethanol production. However, because distillers dried grains with solubles

Observations on the reproductive and larval biology of Blennius pavo (Pisces: Teleostei)

Science.gov (United States)

Westernhagen, H.

1983-09-01

Social behaviour and spawning of adult Blennius pavo kept in the laboratory are described. Eggs are deposited in batches on the walls of artificial spawning places (PVC pipes). One male guards and tends the eggs of different females in one spawning place. Larval hatching occurs in groups according to oviposition. Minimum incubation temperature is around 14 15°C. Larval survival in 1-1 rearing jars is not related to larval total length but to density of larval stock. An experimental population of laboratory reared juvenile and adolescent B. pavo displays a male to female ratio of 1:1.4. Factors possibly influencing the sex ratio of this littoral fish are discussed in view of the situation in its natural environment.

Water Table Management Reduces Tile Nitrate Loss in Continuous Corn and in a Soybean-Corn Rotation

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Craig F. Drury

2001-01-01

Full Text Available Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR system was compared over 8 years (1991 to 1999 to a controlled tile drainage/subirrigation (CDS system on a low-slope (0.05 to 0.1% Brookston clay loam soil (Typic Argiaquoll in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994, continuous corn (Zea mays, L. was grown with annual nitrogen (N fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999, a soybean (Glycine max L., Merr.-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l–1 under DR (11.4 mg N l–1, but not under CDS (7.0 mg N l–1. In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l–1 and CDS (4.0 mg N l–1. During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge

Fumonisins B₁, B₂ and B₃ in corn products, wheat flour and corn oil marketed in Shandong province of China.

Science.gov (United States)

Li, Fenghua; Jiang, Dafeng; Zheng, Fengjia; Chen, Jindong; Li, Wei

2015-01-01

In this study a total of 522 samples were collected from Shandong province of China in 2014 and analysed for the occurrence of fumonisin B1 (FB1), FB2 and FB3 by isotope dilution ultrahigh performance liquid chromatography-tandem mass spectrometry. Fumonisins were detected in 98.1% of the corn products, with the average total level of 369.2 μg kg(-1). The individual average values of FB1, FB2 and FB3 in corn products were 268.3, 53.7 and 47.2 μg kg(-1), respectively. The simultaneous occurrence of FB1, FB2 and FB3 was observed in 76.7% of the corn products. Especially, the results demonstrated that the difference in the contamination levels for fumonisins in these three types of corn products was apparent. In addition, 6.2% of the wheat flour samples were contaminated with FB1, with concentrations ranging from 0.3 to 34.6 µg kg(-1). No FB2 or FB3 was detected in wheat flour. In corn oil samples no fumonisins were detected.

Henry Agard Wallace, the Iowa Corn Yield Tests, and the Adoption of Hybrid Corn

OpenAIRE

Richard C. Sutch

2008-01-01

This research report makes the following claims: 1] There was not an unambiguous economic advantage of hybrid corn over the open-pollinated varieties in 1936. 2] The early adoption of hybrid corn before 1937 can be better explained by a sustained propaganda campaign conducted by the U.S. Department of Agriculture at the direction of the Secretary of Agriculture, Henry Agard Wallace. The Department's campaign echoed that of the commercial seed companies. The most prominent hybrid seed company,...

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish

Science.gov (United States)

Heap, Lucy A.; Vanwalleghem, Gilles C.; Thompson, Andrew W.; Favre-Bulle, Itia; Rubinsztein-Dunlop, Halina; Scott, Ethan K.

2018-01-01

The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH) to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC)/stratum griseum periventriculare (SPV), and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil. PMID:29403362

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish

Directory of Open Access Journals (Sweden)

Lucy A. Heap

2018-01-01

Full Text Available The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC/stratum griseum periventriculare (SPV, and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil.

Measuring larval nematode contamination on cattle pastures: Comparing two herbage sampling methods.

Science.gov (United States)

Verschave, S H; Levecke, B; Duchateau, L; Vercruysse, J; Charlier, J

2015-06-15

Assessing levels of pasture larval contamination is frequently used to study the population dynamics of the free-living stages of parasitic nematodes of livestock. Direct quantification of infective larvae (L3) on herbage is the most applied method to measure pasture larval contamination. However, herbage collection remains labour intensive and there is a lack of studies addressing the variation induced by the sampling method and the required sample size. The aim of this study was (1) to compare two different sampling methods in terms of pasture larval count results and time required to sample, (2) to assess the amount of variation in larval counts at the level of sample plot, pasture and season, respectively and (3) to calculate the required sample size to assess pasture larval contamination with a predefined precision using random plots across pasture. Eight young stock pastures of different commercial dairy herds were sampled in three consecutive seasons during the grazing season (spring, summer and autumn). On each pasture, herbage samples were collected through both a double-crossed W-transect with samples taken every 10 steps (method 1) and four random located plots of 0.16 m(2) with collection of all herbage within the plot (method 2). The average (± standard deviation (SD)) pasture larval contamination using sampling methods 1 and 2 was 325 (± 479) and 305 (± 444)L3/kg dry herbage (DH), respectively. Large discrepancies in pasture larval counts of the same pasture and season were often seen between methods, but no significant difference (P = 0.38) in larval counts between methods was found. Less time was required to collect samples with method 2. This difference in collection time between methods was most pronounced for pastures with a surface area larger than 1 ha. The variation in pasture larval counts from samples generated by random plot sampling was mainly due to the repeated measurements on the same pasture in the same season (residual variance

SILAGE QUALITY OF CORN AND SORGHUM ADDED WITH FORAGE PEANUTS

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WALKÍRIA GUIMARÃES CARVALHO

2016-01-01

Full Text Available Corn and sorghum are standard silage crops because of their fermentative characteristics. While corn and sorghum silages have lower crude protein (CP contents than other crops, intercropping with legumes can increase CP content. Furthermore, one way to increase CP content is the addition of legumes to silage. Consequently, the research objective was to evaluate the fermentative and bromatological characteristics of corn (Zea mays and sorghum (Sorghum bicolor silages added with forage peanuts (Arachis pintoi. The experimental design was completely randomized with four replicates. The treatments consisted of corn silage, sorghum silage, forage peanut silage, corn silage with 30% forage peanut, and sorghum silage with 30% forage peanut. The results showed that the corn and sorghum added with peanut helped to improve the silage fermentative and bromatological characteristics, proving to be an efficient technique for silage quality. The forage peanut silage had lower fermentative characteristics than the corn and sorghum silages. However, the forage peanut silage had a greater CP content, which increased the protein contents of the corn and sorghum silages when intercropped with forage peanuts.

Maize silk antibiotic polyphenol compounds and molecular genetic improvement of resistance to corn earworm (Helicoverpa zea Boddie) in sh2 sweet corn

OpenAIRE

Baozhu Guo; Ana Butrón; Brian T. Scully

2010-01-01

The flavor of sh2 super-sweet corn is preferred by consumers. Unfortunately, sh2 sweet corn has little genetic variation for insect resistance. In this paper we review the functions of two loci, p1 and a1. The P1 allele has a major role in sh2 sweet corn resistance to corn earworm, an allele that was lost in historical selection because of its pleiotropic effect on undesirable cob color and silk browning. The P1 allele has significant effects on biosyntheses of silk antibiotic compounds, mays...

Experimental studies on the larval development of the shrimps Crangon crangon and C. allmanni

Science.gov (United States)

Criales, M. M.; Anger, K.

1986-09-01

Larvae of the shrimps Crangon crangon L. and C. allmanni Kinahan were reared in the laboratory from hatching through metamorphosis. Effects of rearing methods (larval density, application of streptomycin, food) and of salinity on larval development were tested only in C. crangon, influence of temperature was studied in both species. Best results were obtained when larvae were reared individually, with a mixture of Artemia sp. and the rotifer Brachionus plicatilis as food. Streptomycin had partly negative effects and was thus not adopted for standard rearing techniques. All factors tested in this study influenced not only the rates of larval survival and moulting, but also morphogenesis. In both species, in particular in C. crangon, a high degree of variability in larval morphology and in developmental pathways was observed. Unsuitable conditions, e.g. crowding in mass culture, application of antibiotics, unsuitable food (rotifers, phytoplankton), extreme temperatures and salinities, tend to increase the number of larval instars and of morphological forms. The frequency of moulting is controlled mainly by temperature. Regression equations describing the relations between the durations of larval instars and temperature are given for both Crangon species. The number of moults is a linear function of larval age and a power function of temperature. There is high variation in growth (measured as carapace length), moulting frequency, morphogenesis, and survival among hatches originating from different females. The interrelations between these different measures of larval development in shrimps and prawns are discussed.

Sustainable Dry Land Management Model on Corn Agribusiness System

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Yulia Pujiharti

2008-01-01

Full Text Available The study aimed at building model of dry land management. Dynamic System Analysis was used to build model and Powersim 2.51 version for simulating. The parameter used in model were fertilizer (urea, SP-36, ACL, productivity (corn, cassava, mungbean, soil nutrient (N, P, K, crop nutrient requirements (corn, cassava, mungbean, mucuna, price (corn, cassava, mungbeans corn flour, feed, urea, SP-36, KCl, food security credit, area planted of (maize, cassava, mungbean, area harvested of (maize, cassava, mungbean, (corn, cassava, mungbean production, wages and farmer income. Sustainable indicator for ecology aspect was soil fertility level, economic aspects were productivity and farmer income, and social aspects were job possibility and traditions. The simulation result indicated that sustainable dry land management can improve soil fertility and increase farmer revenue, became sustainable farming system and farmer society. On the other hand, conventional dry land management decreased soil fertility and yield, caused farmer earnings to decrease and a farm activity could not be continued. Fertilizer distribution did not fulfill farmer requirement, which caused fertilizer scarcity. Food security credit increased fertilizer application. Corn was processed to corn flour or feed to give value added.

Effect of massing on larval growth rate.

Science.gov (United States)

Johnson, Aidan P; Wallman, James F

2014-08-01

Estimation of minimum postmortem interval commonly relies on predicting the age of blowfly larvae based on their size and an estimate of the temperatures to which they have been exposed throughout their development. The majority of larval growth rate data have been developed using small larval masses in order to avoid excess heat generation. The current study collected growth rate data for larvae at different mass volumes, and assessed the temperature production of these masses, for two forensically important blow fly species, Chrysomya rufifacies and Calliphora vicina. The growth rate of larvae in a small mass, exposed to the higher temperatures equivalent to those experienced by large masses, was also assessed to determine if observed differences were due to the known temperature effects of maggot masses. The results showed that temperature production increased with increasing mass volume, with temperature increases of 11 °C observed in the large Ch. rufifacies masses and increases of 5 °C in the large C. vicina masses. Similarly, the growth rate of the larvae was affected by mass size. The larvae from small masses grown at the higher temperatures experienced by large masses displayed an initial delay in growth, but then grew at a similar rate to those larvae at a constant 23 °C. Since these larvae from masses of equivalent sizes displayed similar patterns of growth rate, despite differing temperatures, and these growth rates differed from larger masses exposed to the same temperatures, it can be concluded that larval growth rate within a mass may be affected by additional factors other than temperature. Overall, this study highlights the importance of understanding the role of massing in larval development and provides initial developmental data for mass sizes of two forensically important blowfly species commonly encountered in Australian forensic casework. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Multipass rotary shear comminution process to produce corn stover particles

Energy Technology Data Exchange (ETDEWEB)

Dooley, James H; Lanning, David N

2015-04-14

A process of comminution of corn stover having a grain direction to produce a mixture of corn stover, by feeding the corn stover in a direction of travel substantially randomly to the grain direction one or more times through a counter rotating pair of intermeshing arrays of cutting discs (D) arrayed axially perpendicular to the direction of corn stover travel.

Uptake and distribution of cadmium in corn

International Nuclear Information System (INIS)

Peel, J.W.; Vetter, R.J.; Christian, J.E.; Kessler, W.V.; McFee, W.W.

1978-01-01

The uptake and distribution of cadmium in corn (Zea mays) treated at various time intervals after planting and sampled at various times after treatment were measured. Cadmium was found to accumulate in all parts sampled. As shown in field studies, stems and leaves generally concentrated more cadmium than did husks, cobs, kernels, silks, or tassels. Samples of stems and leaves from corn treated 23 days after planting and sampled 5 days later exhibited higher concentrations of cadmium than samples taken 25, 45, 65, or 85 days after treatment. Concentrations generally decreased with time. Greenhouse studies showed that corn exposed to cadmium for the longest period of time accumulated the greatest total cadmium. The highest cadmium concentrations were found in the base or lowest leaves sampled 45 days after planting; this suggests a useful technique for quick screening corn crops for cadmium pollution

INFLUENCE OF EUROPEAN CORN BORER (Ostrinia nubilalis Hübner ON CORN HYBRIDS IN NORTH-WEST AND EASTERN CROATIA

Directory of Open Access Journals (Sweden)

Zvjezdana Augustinović

2005-12-01

Full Text Available European corn borer (Ostrinia nubilalis Hubner is one of the major corn pest in the world and in Croatia. Former investigations of corn borer in Croatia covered mostly its Eastern region. In trials conducted in 1998 and 1999 the research was extended to the North Western part of Croatia too. Macro trials were carried out with corn hybrids of FAO groups 200-600 at three localities: Križevci, Agricultural institute Osijek and at «Belje» PIK Karanac. In 1998 the intensity of the corn borer attack at the locality of «Belje» PIK Karanac was about 37.92% and in Agricultural institute Osijek 80.83%. In 1999 it varied between 37.08% at the locality of Agricultural Institute Osijek and 71.20% at the locality in Križevci. The estimated number of holes per plant in all three localities in both years was higher than the number of caterpillars. Length of damage per plant was between 0.38 and 18.80 cm. The data showed significant differences in the intensity of damaging effects on different localities while no significant differences concerning various hybrids were found. The statistical data concerning yield in both years showed significant differences among hybrids, localities and their interactions.

Winter rye cover crop effect on corn seedling pathogens

Science.gov (United States)

Cover crops have been grown successfully in Iowa, but sometimes a cereal rye cover crop preceding corn can reduce corn yields. Our research examines the effect of a rye cover crop on infections of the succeeding corn crop by soil fungal pathogens. Plant measurements included: growth stage, height, r...

Determining the Feasibility of Yellow Corn Production in Mexico

OpenAIRE

Mejia, Maria; Peel, Derrell S.

2009-01-01

Mexico produces large quantities of white corn for human consumption. Yellow corn production, mostly used for feed, has increased lately. Driving factors include higher domestic demand (growing livestock industry) and greater international demand (ethanol industry). This study uses enterprise budgeting to determine the feasibility of producing yellow corn in Mexico.

Acute and Subacute Toxicity Evaluation of Corn Silk Extract.

Science.gov (United States)

Ha, Ae Wha; Kang, Hyeon Jung; Kim, Sun Lim; Kim, Myung Hwan; Kim, Woo Kyoung

2018-03-01

Many studies have reported therapeutic efficacy of corn silk extract. However, research on its toxicity and safe dose range is limited. Thus, the objective of this study was to determine the acute and subacute toxicity of corn silk extract in ICR mice. To determine acute toxicity, corn silk extract containing high levels of maysin was orally administered to mice at a dose of 0 or 2,000 mg/kg. Clinical symptoms, mortality, and body weight changes were recorded for 14 days. To determine subacute toxicity, corn silk extract was orally administered to mice over a 4-week period, and then body weight, water and food consumption, and organ weight were determined. In addition, urine and serum analyses were performed. In the acute toxicity study, no death or abnormal symptoms was observed in all treatment groups during the study period. Body weights did not show any significant change compared to those of the control group. Lethal dose of corn silk extract was estimated to be more than 2,000 mg/kg. In the 4-week subacute toxicity study, there was no corn silk extract related toxic effect on body weight, water intake, food consumption, urine parameters, clinical chemistry, or organ weight. Histopathological examination showed no abnormality related to the administration of corn silk extract at 500 mg/kg. The maximum non-toxic dose of corn silk extract containing high levels of maysin was found to be more than 500 mg/kg.

Resistance Risk Assessment of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Diatraea saccharalis (Lepidoptera: Crambidae) to Vip3Aa20 Insecticidal Protein Expressed in Corn.

Science.gov (United States)

Bernardi, Oderlei; Bernardi, Daniel; Amado, Douglas; Sousa, Renan S; Fatoretto, Julio; Medeiros, Fernanda C L; Conville, Jared; Burd, Tony; Omoto, Celso

2015-12-01

Transgenic Agrisure Viptera 3 corn that expresses Cry1Ab, Vip3Aa20, and EPSPS proteins and Agrisure Viptera expressing Vip3Aa20 are used for control of Spodoptera frugiperda (J.E. Smith) and Diatraea saccharalis (F.) in Brazil. To support a resistance management program, resistance risk assessment studies were conducted to characterize the dose expression of Vip3Aa20 protein and level of control against these species. The Vip3Aa20 expression in Agrisure Viptera 3 and Agrisure Viptera decreased from V6 to V10 stage of growth. However, Vip3Aa20 expression in Agrisure Viptera 3 at V6 and V10 stages was 13- and 16-fold greater than Cry1Ab, respectively. The Vip3Aa20 expression in lyophilized tissue of Agrisure Viptera 3 and Agrisure Viptera diluted 25-fold in an artificial diet caused complete larval mortality of S. frugiperda and D. saccharalis. In contrast, lyophilized tissue of Bt11 at the same dilution does not provide complete mortality of these species. Agrisure Viptera 3 and Agrisure Viptera also caused a high level of mortality against S. frugiperda and D. saccharalis. Moreover, 100% mortality was observed for S. frugiperda larvae (neonates through fifth-instar larvae) when fed in corn with the Vip trait technology. Viptera corn achieves a high level of control against S. frugiperda and D. saccharalis providing a high dose, which is an important determination to support the refuge strategy for an effective resistance management program. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of Bt Corn with Pyramided Genes on Efficacy and Insect Resistance Management for the Asian Corn Borer in China.

Directory of Open Access Journals (Sweden)

Fan Jiang

Full Text Available A Bt corn hybrid (AcIe with two Bt genes (cry1Ie and cry1Ac was derived by breeding stack from line expressing Cry1Ie and a line expressing Cry1Ac. Efficacy of this pyramided Bt corn hybrid against the Asian corn borer (ACB, Ostrinia furnacalis, was evaluated. We conducted laboratory bioassays using susceptible and resistant ACB strains fed on artificial diet or fresh plant tissues. We also conducted field trials with artificial infestations of ACB neonates at the V6 and silk stages. The toxin-diet bioassay data indicated that mixtures of Cry1Ac and Cry1Ie proteins had synergistic insecticidal efficacy. The plant tissue bioassay data indicated that Bt corn hybrids expressing either a single toxin (Cry1Ac or Cry1Ie or two toxins had high efficacy against susceptible ACB. Damage ratings in the field trials indicated that the Bt corn hybrids could effectively protect against 1st and the 2nd generation ACB in China. The hybrid line with two Bt genes showed a higher efficacy against ACB larvae resistant to Cry1Ac or CryIe than the hybrid containing one Bt gene, and the two gene hybrid would have increased potential for managing or delaying the evolution of ACB resistance to Bt corn plants.

Evaluation of Bt Corn with Pyramided Genes on Efficacy and Insect Resistance Management for the Asian Corn Borer in China.

Science.gov (United States)

Jiang, Fan; Zhang, Tiantao; Bai, Shuxiong; Wang, Zhenying; He, Kanglai

2016-01-01

A Bt corn hybrid (AcIe) with two Bt genes (cry1Ie and cry1Ac) was derived by breeding stack from line expressing Cry1Ie and a line expressing Cry1Ac. Efficacy of this pyramided Bt corn hybrid against the Asian corn borer (ACB), Ostrinia furnacalis, was evaluated. We conducted laboratory bioassays using susceptible and resistant ACB strains fed on artificial diet or fresh plant tissues. We also conducted field trials with artificial infestations of ACB neonates at the V6 and silk stages. The toxin-diet bioassay data indicated that mixtures of Cry1Ac and Cry1Ie proteins had synergistic insecticidal efficacy. The plant tissue bioassay data indicated that Bt corn hybrids expressing either a single toxin (Cry1Ac or Cry1Ie) or two toxins had high efficacy against susceptible ACB. Damage ratings in the field trials indicated that the Bt corn hybrids could effectively protect against 1st and the 2nd generation ACB in China. The hybrid line with two Bt genes showed a higher efficacy against ACB larvae resistant to Cry1Ac or CryIe than the hybrid containing one Bt gene, and the two gene hybrid would have increased potential for managing or delaying the evolution of ACB resistance to Bt corn plants.

Effect of eastern gamagrass on fall armyworm and corn earworm development

Science.gov (United States)

The fall armyworm, Spodoptera frugiperda (J.E. Smith) and the corn earworm, Helicoverpa zea (Boddie) are two important corn pests in the southern U.S. states. Effect of the leaves from the corn relative, the Eastern gamagrass (Tripsacum dactyloides L.) on fall armyworm and corn earworm development ...

Field-Evolved Resistance in Corn Earworm to Cry Proteins Expressed by Transgenic Sweet Corn

Science.gov (United States)

Dively, Galen P.; Finkenbinder, Chad

2016-01-01

Background Transgenic corn engineered with genes expressing insecticidal toxins from the bacterium Bacillus thuringiensis (Berliner) (Bt) are now a major tool in insect pest management. With its widespread use, insect resistance is a major threat to the sustainability of the Bt transgenic technology. For all Bt corn expressing Cry toxins, the high dose requirement for resistance management is not achieved for corn earworm, Helicoverpa zea (Boddie), which is more tolerant to the Bt toxins. Methodology/Major Findings We present field monitoring data using Cry1Ab (1996–2016) and Cry1A.105+Cry2Ab2 (2010–2016) expressing sweet corn hybrids as in-field screens to measure changes in field efficacy and Cry toxin susceptibility to H. zea. Larvae successfully damaged an increasing proportion of ears, consumed more kernel area, and reached later developmental stages (4th - 6th instars) in both types of Bt hybrids (Cry1Ab—event Bt11, and Cry1A.105+Cry2Ab2—event MON89034) since their commercial introduction. Yearly patterns of H. zea population abundance were unrelated to reductions in control efficacy. There was no evidence of field efficacy or tissue toxicity differences among different Cry1Ab hybrids that could contribute to the decline in control efficacy. Supportive data from laboratory bioassays demonstrate significant differences in weight gain and fitness characteristics between the Maryland H. zea strain and a susceptible strain. In bioassays with Cry1Ab expressing green leaf tissue, Maryland H. zea strain gained more weight than the susceptible strain at all concentrations tested. Fitness of the Maryland H. zea strain was significantly lower than that of the susceptible strain as indicated by lower hatch rate, longer time to adult eclosion, lower pupal weight, and reduced survival to adulthood. Conclusions/Significance After ruling out possible contributing factors, the rapid change in field efficacy in recent years and decreased susceptibility of H. zea to Bt

Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

NARCIS (Netherlands)

Bukhari, S.T.; Middelman, A.; Koenraadt, C.J.M.; Takken, W.; Knols, B.G.J.

2010-01-01

Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density), fungus (species

Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

Directory of Open Access Journals (Sweden)

Thelen Kurt D

2010-06-01

Full Text Available Abstract Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS and matured whole corn plants (WCP as feedstocks to produce ethanol using ammonia fiber expansion (AFEX pretreatment followed by enzymatic hydrolysis (at low enzyme loadings and cofermentation (for both glucose and xylose using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan. Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading CS hydrolyzate (resulting

Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

Science.gov (United States)

2010-01-01

Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant) is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS) and matured whole corn plants (WCP) as feedstocks to produce ethanol using ammonia fiber expansion (AFEX) pretreatment followed by enzymatic hydrolysis (at low enzyme loadings) and cofermentation (for both glucose and xylose) using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST) strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch) had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan). Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading) CS hydrolyzate (resulting in 28 g/L ethanol

Climate forecasts for corn producer decision making

Science.gov (United States)

Corn is the most widely grown crop in the Americas, with annual production in the United States of approximately 332 million metric tons. Improved climate forecasts, together with climate-related decision tools for corn producers based on these improved forecasts, could substantially reduce uncertai...

7 CFR 457.129 - Fresh market sweet corn crop insurance provisions.

Science.gov (United States)

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Fresh market sweet corn crop insurance provisions. 457... sweet corn crop insurance provisions. The fresh market sweet corn crop insurance provisions for the 2008... Reinsured Policies Fresh Market Sweet Corn Crop Provisions 1. Definitions Allowable cost.—The dollar amount...

Growing ethanol sector drives corn supply chain shift for the last decade

Science.gov (United States)

Kim, T.; Schmitt, J.; Brauman, K. A.; Smith, T. M.; Suh, K.

2017-12-01

The US is the largest producer in the world, 89% of corn production uses in domestic demands in 2012. Carbon emission and irrigated water usage in the corn farming stage are hot-spot in the meat production sectors, comprise 37% of all US corn demand. The annual capacity of the ethanol sector increases from 6.5 billion gallons to 15.3 billion gallons for the last decade. The growth of corn demand in ethanol sector makes corn supply chain shift. Most of the ethanol plants located in the Mid-west where is the top 12 corn producing states. Therefore animal feeds take more supply from the other states. The purpose of this study is to estimate environmental impacts and water scarcity associated embedded corn by the temporal and spatial corn supply chain model based on a cost minimization. We use publicly available county-level data on corn production, feed demands, aggregative carbon emission and irrigated water usage in farming state, and a water depletion index as a metric for determining water scarcity. The water stressed counties produce 23.3% of US total corn production in 2012, and the irrigated corn is 14.2%. We simulated the corn supply chain using linear programming and developed the web-based visualization tools called FoodS3 (Food Systems Supply-chain Sustainability tool, http://foods3.org).

Replication of Holograms with Corn Syrup by Rubbing

Directory of Open Access Journals (Sweden)

Arturo Olivares-Pérez

2012-08-01

Full Text Available Corn syrup films are used to replicate holograms in order to fabricate micro-structural patterns without the toxins commonly found in photosensitive salts and dyes. We use amplitude and relief masks with lithographic techniques and rubbing techniques in order to transfer holographic information to corn syrup material. Holographic diffraction patterns from holographic gratings and computer Fourier holograms fabricated with corn syrup are shown. We measured the diffraction efficiency parameter in order to characterize the film. The versatility of this material for storage information is promising. Holographic gratings achieved a diffraction efficiency of around 8.4% with an amplitude mask and 36% for a relief mask technique. Preliminary results using corn syrup as an emulsion for replicating holograms are also shown in this work.

Replication of Holograms with Corn Syrup by Rubbing

Science.gov (United States)

Mejias-Brizuela, Nildia Y.; Olivares-Pérez, Arturo; Ortiz-Gutiérrez, Mauricio

2012-01-01

Corn syrup films are used to replicate holograms in order to fabricate micro-structural patterns without the toxins commonly found in photosensitive salts and dyes. We use amplitude and relief masks with lithographic techniques and rubbing techniques in order to transfer holographic information to corn syrup material. Holographic diffraction patterns from holographic gratings and computer Fourier holograms fabricated with corn syrup are shown. We measured the diffraction efficiency parameter in order to characterize the film. The versatility of this material for storage information is promising. Holographic gratings achieved a diffraction efficiency of around 8.4% with an amplitude mask and 36% for a relief mask technique. Preliminary results using corn syrup as an emulsion for replicating holograms are also shown in this work.

Forecasting corn production in Serbia using ARIMA model

Directory of Open Access Journals (Sweden)

Ilić Ivana

2016-01-01

Full Text Available Agricultural crop production is closely related to climate, as a decisive success factor. Temperature fluctuations and changes in the volume of precipitation are the main factors affecting the growth and development of crops, and, ultimately, the quantity produced. Corn is the most common crop necessary to provide for domestic needs, and a strategic product for export. Production of corn in the period from 1947 to 2014 in Serbia had an oscillatory trend, with significant jumps and falls in production. The subject of this paper is the forecasting of future trends in corn production in Serbia. Building on the subject, the purpose of this paper is to create the model for forecasting future corn production and establishing its trends.

Biodiesel production from corn oil by transesterification process

International Nuclear Information System (INIS)

Khan, N.A.; Dessouky, H.

2009-01-01

There is much political demand and economic pressure to convert agricultural surpluses into material, such as motor fuel, in which the world is deficient. Transport industry is primary consumer of crude oil. Due to scarcity of known petroleum reserves, the possible alternative fuel for use in present engine technology is biofuels. Europe, USA and Brazil are successfully using biofuels. Biofuels causes less environmental pollution as compared to normal petro fuels. As a fuel, ethanol (gasohol) is used in internal combustion engine while methyester (Biodiesel) is used in diesel engines with same or better performance as compared to petro fuels. Corn is very valuable crop with numerous industrial applications, and is used in more than 300 modern industries, including the manufacture of textiles, paper, adhesives, insecticides, paints, soaps, explosives and many more. Presently the biggest source of ethanol production is from corn (produced by USA). Edible oil can also be extracted from corn which is normally used for cooking and it can be used for biodiesel production. Many countries are experimenting on fats and oil to get feasible data for production of biodiesel. Presently USA prefer to use soybean oil as raw material for commercial production of biodiesel while in Europe rapeseed oil is preferred, so therefore, it depends upon the availability of raw material in particular area and may change from location to location. In Pakistan we started with corn oil to produce biodiesel by transesterification method. In present study different design parameters such as effect of temperature, catalyst concentration, molar ratio, and Stirrer speed were founded for better conversion of neat and used corn oil into biodiesel. The optimum parameters proposed for neat corn oil are 0.5% of catalyst based on weight of corn oil, temperature between 50 deg. C to 60 deg. C, reaction time 15 minutes, molar ratio of 6:1 and speed of stirrer 155 rpm. In case of used corn oil high catalyst

7 CFR 407.11 - Group risk plan for corn.

Science.gov (United States)

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Group risk plan for corn. 407.11 Section 407.11..., DEPARTMENT OF AGRICULTURE GROUP RISK PLAN OF INSURANCE REGULATIONS § 407.11 Group risk plan for corn. The provisions of the Group Risk Plan for Corn for the 2000 and succeeding crop years are as follows: 1...

Physicochemical and sensory qualities of spiced soy-corn milk ...

African Journals Online (AJOL)

Soy-corn milk type was produced from a blend of soybean milk and corn milk extract at a ratio of 3:1. The soy-corn milk type was spiced with ginger and garlic extract respectively to improve the taste. Total dissolved solid (TDS), total titrable acidity (TTA) specific gravity (SG), apparent colloidal stability, pH and sensory ...

Passive larval transport explains recent gene flow in a Mediterranean gorgonian

Science.gov (United States)

Padrón, Mariana; Costantini, Federica; Baksay, Sandra; Bramanti, Lorenzo; Guizien, Katell

2018-06-01

Understanding the patterns of connectivity is required by the Strategic Plan for Biodiversity 2011-2020 and will be used to guide the extension of marine protection measures. Despite the increasing accuracy of ocean circulation modelling, the capacity to model the population connectivity of sessile benthic species with dispersal larval stages can be limited due to the potential effect of filters acting before or after dispersal, which modulates offspring release or settlement, respectively. We applied an interdisciplinary approach that combined demographic surveys, genetic methods (assignment tests and coalescent-based analyses) and larval transport simulations to test the relative importance of demographics and ocean currents in shaping the recent patterns of gene flow among populations of a Mediterranean gorgonian ( Eunicella singularis) in a fragmented rocky habitat (Gulf of Lion, NW Mediterranean Sea). We show that larval transport is a dominant driver of recent gene flow among the populations, and significant correlations were found between recent gene flow and larval transport during an average single dispersal event when the pelagic larval durations (PLDs) ranged from 7 to 14 d. Our results suggest that PLDs that efficiently connect populations distributed over a fragmented habitat are filtered by the habitat layout within the species competency period. Moreover, a PLD ranging from 7 to 14 d is sufficient to connect the fragmented rocky substrate of the Gulf of Lion. The rocky areas located in the centre of the Gulf of Lion, which are currently not protected, were identified as essential hubs for the distribution of migrants in the region. We encourage the use of a range of PLDs instead of a single value when estimating larval transport with biophysical models to identify potential connectivity patterns among a network of Marine Protected Areas or even solely a seascape.

The effects of corn silk on glycaemic metabolism

OpenAIRE

Han Linna; Liu Tongjun; Guo Jianyou; Liu Yongmei

2009-01-01

Abstract Background Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk ...

Larval outbreaks in West Greenland

DEFF Research Database (Denmark)

Lund, Magnus; Raundrup, Katrine; Westergaard-Nielsen, Andreas

2017-01-01

effects of a larval outbreak in 2011 on vegetation productivity and CO2 exchange. We estimate a decreased carbon (C) sink strength in the order of 118–143 g C m−2, corresponding to 1210–1470 tonnes C at the Kobbefjord catchment scale. The decreased C sink was, however, counteracted the following years...

Influence of variety and harvest maturity on phytochemical content in corn silk.

Science.gov (United States)

Sarepoua, Eakrin; Tangwongchai, Ratchada; Suriharn, Bhalang; Lertrat, Kamol

2015-02-15

Corn silk has been used as a traditional herb in Asia. The objective of this study was to evaluate variability in phytochemicals in corn varieties at three maturity stages of corn silk. Ten vegetable corn varieties were evaluated in a completely randomized design with three replications. Data were recorded for total phenolic (TPC), total flavonoids (TFC), total anthocyanin (TAC) and antioxidant activity (AA) by DPPH free-radical-scavenging assays. Differences among corn varieties were observed for all parameters at all maturity stages, and the interactions between maturity stage and corn variety were significant. TPC and TAC were highest at the milky stage, whereas TFC and AA were highest at the silking stage. TPC, TFC and AA were highest in super sweet corn and white corn at the silking stage. PWC5 variety of purple waxy corn at the milky stage had the highest values for all parameters, and it is useful for further development of functional food products. Copyright © 2014 Elsevier Ltd. All rights reserved.

How Metamorphosis Is Different in Plethodontids: Larval Life History Perspectives on Life-Cycle Evolution

Science.gov (United States)

Beachy, Christopher K.; Ryan, Travis J.; Bonett, Ronald M.

2017-01-01

Plethodontid salamanders exhibit biphasic, larval form paedomorphic, and direct developing life cycles. This diversity of developmental strategies exceeds that of any other family of terrestrial vertebrate. Here we compare patterns of larval development among the three divergent lineages of biphasic plethodontids and other salamanders. We discuss how patterns of life-cycle evolution and larval ecology might have produced a wide array of larval life histories. Compared with many other salamanders, most larval plethodontids have relatively slow growth rates and sometimes exceptionally long larval periods (up to 60 mo). Recent phylogenetic analyses of life-cycle evolution indicate that ancestral plethodontids were likely direct developers. If true, then biphasic and paedomorphic lineages might have been independently derived through different developmental mechanisms. Furthermore, biphasic plethodontids largely colonized stream habitats, which tend to have lower productivity than seasonally ephemeral ponds. Consistent with this, plethodontid larvae grow very slowly, and metamorphic timing does not appear to be strongly affected by growth history. On the basis of this, we speculate that feeding schedules and stress hormones might play a comparatively reduced role in governing the timing of metamorphosis of stream-dwelling salamanders, particularly plethodontids. PMID:29269959

The urodelean Mauthner cell. Morphology of the afferent synapses to the M-cell of larval Salamandra salamandra

Energy Technology Data Exchange (ETDEWEB)

Cioni, C.; De Palma, F.; De Vito, L.; Stefanelli, A. [Rome, Univ. (Italy). Dipt. di Biologia Animale e dell`Uomo

1997-12-31

In the present work the fine morphology and the distribution of the afferent synapses to the Mauthner cell of larval Salamandra salamandra are described. The aim of the study is to characterize the synaptic bed in the larvae of this terrestrial salamander in order to compare it with that of larval axolotl and larval anurans. Four main types of afferent endings have been identified: myelinated club endings, round-vesicle end bulbs, flattened-vesicle end bulbs and spiral fibers endings. The M-cell afferent synaptology of larval stages of terrestrial amphibians is quite similar to that previously observed in larval stages of aquatic species. This fact can be related to the fundamental similarities between the larval lifestyles.

The urodelean Mauthner cell. Morphology of the afferent synapses to the M-cell of larval Salamandra salamandra

Energy Technology Data Exchange (ETDEWEB)

Cioni, C; De Palma, F; De Vito, L; Stefanelli, A [Rome, Univ. (Italy). Dipt. di Biologia Animale e dell` Uomo

1998-12-31

In the present work the fine morphology and the distribution of the afferent synapses to the Mauthner cell of larval Salamandra salamandra are described. The aim of the study is to characterize the synaptic bed in the larvae of this terrestrial salamander in order to compare it with that of larval axolotl and larval anurans. Four main types of afferent endings have been identified: myelinated club endings, round-vesicle end bulbs, flattened-vesicle end bulbs and spiral fibers endings. The M-cell afferent synaptology of larval stages of terrestrial amphibians is quite similar to that previously observed in larval stages of aquatic species. This fact can be related to the fundamental similarities between the larval lifestyles.

Corn Stover Availability for Biomass Conversion: Situation Analysis

International Nuclear Information System (INIS)

Hess, J. Richard; Kenney, Kevin L.; Wright, Christopher T.; Perlack, Robert; Turhollow, Anthony

2009-01-01

As biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material attributes are emerging as major barriers to the availability of corn stover for biorefining. While systems do exist to supply corn stover as feedstock to biorefining facilities, stover material attributes affecting physical deconstruction, such as densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems. In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment capacity/efficiency, dry matter loss, and capital use efficiency. However, this study of a large, square-bale corn stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional-bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses in harvesting and collection and storage. Finally, the backbone of an effective stover supply system design is the optimization of intended and minimization of unintended material property changes as the corn stover passes through the individual supply system processes from the field to the biorefinery conversion processes

Adaptive locomotor behavior in larval zebrafish.

Science.gov (United States)

Portugues, Ruben; Engert, Florian

2011-01-01

In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish.

Aflatoxin contamination in corn sold for wildlife feed in texas.

Science.gov (United States)

Dunham, Nicholas R; Peper, Steven T; Downing, Carson D; Kendall, Ronald J

2017-05-01

Supplemental feeding with corn to attract and manage deer is a common practice throughout Texas. Other species, including northern bobwhites (Colinus virginianus), are commonly seen feeding around supplemental deer feeders. In many cases, supplemental feeding continues year-round so feed supply stores always have supplemental corn in stock. Fluctuating weather and improper storage of corn can lead to and/or amplify aflatoxin contamination. Due to the recent decline of bobwhites throughout the Rolling Plains ecoregion of Texas, there has been interest in finding factors such as toxins that could be linked to their decline. In this study, we purchased and sampled supplemental corn from 19 locations throughout this ecoregion to determine if aflatoxin contamination was present in individual bags prior to being dispersed to wildlife. Of the 57 bags sampled, 33 bags (approximately 58%) contained aflatoxin with a bag range between 0.0-19.91 parts per billion (ppb). Additionally, three metal and three polypropylene supplemental feeders were each filled with 45.4 kg of triple cleaned corn and placed in an open field to study long-term aflatoxin buildup. Feeders were sampled every 3 months from November 2013-November 2014. Average concentration of aflatoxin over the year was 4.08 ± 2.53 ppb (±SE) in metal feeders, and 1.43 ± 0.89 ppb (±SE) in polypropylene feeders. The concentration of aflatoxins is not affected by the type of feeder (metal vs polypropylene), the season corn was sampled, and the location in the feeder (top, middle, bottom) where corn is sampled. It is unlikely that corn used in supplemental feeders is contributing to the bobwhite decline due to the low levels of aflatoxin found in purchased corn and long-term storage of corn used in supplemental feeders.

Effect of corticosterone on larval growth, antipredator behaviour and metamorphosis of Hylarana indica.

Science.gov (United States)

Kulkarni, P S; Gramapurohit, N P

2017-09-15

Corticosterone (CORT), a principal glucocorticoid in amphibians, is known to regulate diverse physiological processes including growth and metamorphosis of anuran tadpoles. Environmental stressors activate the neuroendocrine stress axis (hypothalamus-pituitary-interrenal axis, HPI) leading to an acute increase in CORT, which in turn, helps in coping with particular stress. However, chronic increase in CORT can negatively affect other physiological processes such as growth and metamorphosis. Herein, we studied the effect of exogenous CORT on larval growth, antipredator behaviour and metamorphic traits of Hylarana indica. Embryonic exposure to 5 or 20μg/L CORT did not affect their development, hatching duration as well as larval growth and metamorphosis. Exposure of tadpoles to 10 or 20μg/L CORT throughout larval development caused slower growth and development leading to increased body mass at stage 37. However, body and tail morphology of tadpoles was not affected. Interestingly, larval exposure to 5, 10 or 20μg/L CORT enhanced their antipredator response against kairomones in a concentration-dependent manner. Further, larval exposure to increasing concentrations of CORT resulted in the emergence of heavier froglets at 10 and 20μg/L while, delaying metamorphosis at all concentrations. Interestingly, the heavier froglets had shorter hindlimbs and consequently shorter jump distances. Tadpoles exposed to 20μg/L CORT during early, mid or late larval stages grew and developed slowly but tadpole morphology was not altered. Interestingly, exposure during early or mid-larval stages resulted in an enhanced antipredator response. These individuals metamorphosed later but at higher body mass while SVL was unaffected. Copyright © 2016 Elsevier Inc. All rights reserved.

Inhibitory Effect of Corn Silk on Skin Pigmentation

OpenAIRE

Sang Yoon Choi; Yeonmi Lee; Sung Soo Kim; Hyun Min Ju; Ji Hwoon Baek; Chul-Soo Park; Dong-Hyuk Lee

2014-01-01

In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin prod...

Experimental investigation of pyrolysis process of corn straw

OpenAIRE

Lei Wang; Shengqiang Shen; Shuhua Yang; Xinguang Shi

2010-01-01

The present paper was performed to analyze the pyrolysis process of corn straw. Based on the thermogravimetric analysis, the component of pyrolysis gas of corn straw was tested using the gas chromatograph analyzer. Experimental results showed that, as the reaction temperature increases, the component of H 2 and CH 4 increases, whereas the component of CO and CO 2 decreases. Finally, the mechanism of pyrolysis process of corn straw was revealed from the point of view of the molecular structure...

Mild alkaline presoaking and organosolv pretreatment of corn stover and their impacts on corn stover composition, structure, and digestibility.

Science.gov (United States)

Qing, Qing; Zhou, Linlin; Guo, Qi; Gao, Xiaohang; Zhang, Yan; He, Yucai; Zhang, Yue

2017-06-01

An efficient strategy was developed in current work for biochemical conversion of carbohydrates of corn stover into monosaccharides. Corn stover was first presoaked in mild alkaline solution (1% Na 2 S) under 40°C for 4h, after which about 35.3% of the lignin was successfully removed while the specific surface area was notably enlarged. Then the presoaked solids were subjected to organosolv pretreatment that employed 20% methanol with an addition of 0.2% HCl as catalyst at 160°C for 20min, and the maximum total sugar yield of the pretreated corn stover achieved was 98.6%. The intact structure of corn stover was disrupted by this two-step process, which resulted in a porous but crystalline structure of the regenerated solids that were mainly composed of cellulose. The enlarged specific surface area and increased accessibility made the regenerated solids highly digestible by a moderate enzyme loading. Copyright © 2017 Elsevier Ltd. All rights reserved.

Larval diet affects mosquito development and permissiveness to Plasmodium infection.

Science.gov (United States)

Linenberg, Inbar; Christophides, George K; Gendrin, Mathilde

2016-12-02

The larval stages of malaria vector mosquitoes develop in water pools, feeding mostly on microorganisms and environmental detritus. Richness in the nutrient supply to larvae influences the development and metabolism of larvae and adults. Here, we investigated the effects of larval diet on the development, microbiota content and permissiveness to Plasmodium of Anopheles coluzzii. We tested three fish diets often used to rear mosquitoes in the laboratory, including two pelleted diets, Dr. Clarke's Pool Pellets and Nishikoi Fish Pellets, and one flaked diet, Tetramin Fish-Flakes. Larvae grow and develop faster and produce bigger adults when feeding on both types of pellets compared with flakes. This correlates with a higher microbiota load in pellet-fed larvae, in agreement with the known positive effect of the microbiota on mosquito development. Larval diet also significantly influences the prevalence and intensity of Plasmodium berghei infection in adults, whereby Nishikoi Fish Pellets-fed larvae develop into adults that are highly permissive to parasites and survive longer after infection. This correlates with a lower amount of Enterobacteriaceae in the midgut microbiota. Together, our results shed light on the influence of larval feeding on mosquito development, microbiota and vector competence; they also provide useful data for mosquito rearing.

Ácido fítico de híbridos de milho e alguns produtos industrializados = Phytic acid in corn hybrids and in some industrialized corn products

Directory of Open Access Journals (Sweden)

Tatiana Shizue Fukuji

2008-01-01

Full Text Available O ácido fítico (AF ou mio-inositol hexafosfato está presente principalmente em cereais, e o germe de milho apresenta teor elevado, com cerca de 6,0 a 7,0% em base seca. Devido a sua propriedade quelante com metais di e tri-valentes, o AF apresenta capacidade antioxidante com eficaz atuação na inibição de reações de oxidação. O teor de AF foi determinado no germe e endosperma de 11 híbridos de milhos, cultivados no Estado do Paraná, e em diferentes produtos industrializados de milho. Os germes de híbridos de milho foram caracterizados como componentes do milho, com elevado teor e osendospermas com baixo teor de AF. Os produtos derivados de milho, elaborados basicamente com endosperma tais como canjica, creme de milho, farinha de milho e fubá fino, apresentaram menor teor de AF, enquanto aqueles originários dos germes desengordurado, fino, gordo e película de milho apresentaram maior teor de AF.Phytic acid (PA, also known as myoinositol hexaphosphate, is found mainly in cereal grains. Corn germ has high concentrations of PA – from 6.0 to 7.0% on a dry weight basis. Due to its chelating properties on di- and trivalent metals, PA has antioxidantattributes, effectively inhibiting oxidation reactions. In this study, PA levels were determined in the germ and endosperm of eleven corn hybrids cultivate in Paraná State (Brazil, and also in several industrialized corn products. Corn hybrid germs were characterized as corn components with high PA levels, whereas endosperms featuredlow levels of PA. Corn-based industrialized products, derived mostly from corn endosperm (such as canjica, creamed corn, corn flour and cornmeal featured the lowest PA values. Conversely, defatted corn germs and corn cuticle showed the highest PA levels.

Larval settlement and metamorphosis of the mussel Mytilus coruscus in response to monospecific bacterial biofilms.

Science.gov (United States)

Yang, Jin-Long; Shen, Pei-Jing; Liang, Xiao; Li, Yi-Feng; Bao, Wei-Yang; Li, Jia-Le

2013-01-01

The effects of bacterial biofilms (BFs) on larval settlement and metamorphosis of the mussel, Mytilus coruscus, were investigated in the laboratory. Of nine different isolates, Shewanella sp.1 BF induced the highest percentage of larval settlement and metamorphosis, whereas seven other isolates had a moderate inducing activity and one isolate, Pseudoalteromonas sp. 4, had a no inducing activity. The inducing activity of individual bacterial isolates was not correlated either with their phylogenetic relationship or with the surfaces from which they were isolated. Among the eight bacterial species that demonstrated inducing activity, bacterial density was significantly correlated with the inducing activity for each strain, with the exception of Vibrio sp. 1. The Shewanella sp. 1 BF cue that was responsible for inducing larval settlement and metamorphosis was further investigated. Treatment of the BFs with formalin, antibiotics, ultraviolet irradiation, heat, and ethanol resulted in a significant decrease in their inducing activities and cell survival. BF-conditioned water (CW) did not induce larval metamorphosis, but it triggered larval settlement behavior. A synergistic effect of CW with formalin-fixed Shewanella sp. 1 BF significantly promoted larval metamorphosis. Thus, a cocktail of chemical cues derived from bacteria may be necessary to stimulate larval settlement and metamorphosis in this species.

The role of individual variation in marine larval dispersal

KAUST Repository

Nanninga, Gerrit B.

2014-12-08

The exchange of individuals among patchy habitats plays a central role in spatial ecology and metapopulation dynamics. Dispersal is frequently observed to vary non-randomly within populations (e.g., short vs. long), indicating that variability among individuals may shape heterogeneity in patterns of connectivity. The concept of context- and condition-dependent dispersal describes the balance between the costs and benefits of dispersal that arises from the interaction of temporal and spatial landscape heterogeneity (the context) with phenotypic variability among individuals (the condition). While this hypothesis is widely accepted in terrestrial theory, it remains questionable to what extent the concept of adaptive dispersal strategies may apply to marine larval dispersal, a process that is largely determined by stochastic forces. Yet, larvae of many taxa exhibit strong navigational capabilities and there is mounting evidence of widespread intra-specific variability in biological traits that are potentially correlated with dispersal potential. While so far there are few known examples of real larval dispersal polymorphisms, intra-specifically variable dispersal strategies may be common in marine systems. Whether adaptive or not, it is becoming apparent that inter-individual heterogeneity in morphology, behavior, condition, and life history traits may have critical effects on population-level heterogeneity in dispersal. Here, we explore the eco-evolutionary causes and consequences of intrinsic and extrinsic variability on larval dispersal by synthesizing the existing literature and drawing conceptual parallels from terrestrial theory. We emphasize the potential importance of larval dispersal polymorphisms in marine population dynamics.

Embryogenesis and larval biology of the cold-water coral Lophelia pertusa.

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Ann I Larsson

Full Text Available Cold-water coral reefs form spectacular and highly diverse ecosystems in the deep sea but little is known about reproduction, and virtually nothing about the larval biology in these corals. This study is based on data from two locations of the North East Atlantic and documents the first observations of embryogenesis and larval development in Lophelia pertusa, the most common framework-building cold-water scleractinian. Embryos developed in a more or less organized radial cleavage pattern from ∼ 160 µm large neutral or negatively buoyant eggs, to 120-270 µm long ciliated planulae. Embryogenesis was slow with cleavage occurring at intervals of 6-8 hours up to the 64-cell stage. Genetically characterized larvae were sexually derived, with maternal and paternal alleles present. Larvae were active swimmers (0.5 mm s(-1 initially residing in the upper part of the water column, with bottom probing behavior starting 3-5 weeks after fertilization. Nematocysts had developed by day 30, coinciding with peak bottom-probing behavior, and possibly an indication that larvae are fully competent to settle at this time. Planulae survived for eight weeks under laboratory conditions, and preliminary results indicate that these planulae are planktotrophic. The late onset of competency and larval longevity suggests a high dispersal potential. Understanding larval biology and behavior is of paramount importance for biophysical modeling of larval dispersal, which forms the basis for predictions of connectivity among populations.

Comparison of corn and switchgrass on marginal soils for bioenergy

Energy Technology Data Exchange (ETDEWEB)

Varvel, G.E.; Vogel, K.P.; Mitchell, R.B. [USDA-ARS, 344 Keim Hall, University of Nebraska-Lincoln, P.O. Box 830937, Lincoln, NE 68583-0937 (United States); Follett, R.F. [USDA-ARS, Room S-100, 2150 Centre Avenue Building D, Ft. Collins, CO 80526-8119 (United States); Kimble, J.M. [USDA-NRCS, National Soil Survey Center, 100 Centennial Mall North, Lincoln, NE 68508-3866 (United States)

2008-01-15

Crop residues such as corn (Zea mays L.) stover are viewed as an abundant and inexpensive source of biomass that can be removed from fields to produce bioenergy. Assumptions include that with minimum or no-tillage farming methods, there will be no deleterious production or environmental effects. A long-term field study was established in eastern Nebraska, USA, to compare the switchgrass managed as a biomass energy crop versus no-till corn on a non-irrigated site, marginal for row-crop production, in the western Corn Belt. Our objective in this paper is to report on corn stover removal effects on corn grain yields and potential ethanol production in both cropping systems. Corn, under no-till management, and switchgrass were grown at three N fertilizer levels. In the first 5 years (2001-2005), removal of half the available stover significantly reduced corn yields. During that same time period, the potential ethanol yield for switchgrass was equal to or greater than the potential total ethanol yield of corn grain and harvested stover fertilized at the same optimum N rate. The effect of crop residue removal on crop productivity needs to be investigated in other agro-ecosystems and the potential use of dedicated perennial biomass energy crops should remain a viable renewable energy option on non-irrigated marginal croplands. (author)

A Remote Sensing-Derived Corn Yield Assessment Model

Science.gov (United States)

Shrestha, Ranjay Man

be further associated with the actual yield. Utilizing satellite remote sensing products, such as daily NDVI derived from Moderate Resolution Imaging Spectroradiometer (MODIS) at 250 m pixel size, the crop yield estimation can be performed at a very fine spatial resolution. Therefore, this study examined the potential of these daily NDVI products within agricultural studies and crop yield assessments. In this study, a regression-based approach was proposed to estimate the annual corn yield through changes in MODIS daily NDVI time series. The relationship between daily NDVI and corn yield was well defined and established, and as changes in corn phenology and yield were directly reflected by the changes in NDVI within the growing season, these two entities were combined to develop a relational model. The model was trained using 15 years (2000-2014) of historical NDVI and county-level corn yield data for four major corn producing states: Kansas, Nebraska, Iowa, and Indiana, representing four climatic regions as South, West North Central, East North Central, and Central, respectively, within the U.S. Corn Belt area. The model's goodness of fit was well defined with a high coefficient of determination (R2>0.81). Similarly, using 2015 yield data for validation, 92% of average accuracy signified the performance of the model in estimating corn yield at county level. Besides providing the county-level corn yield estimations, the derived model was also accurate enough to estimate the yield at finer spatial resolution (field level). The model's assessment accuracy was evaluated using the randomly selected field level corn yield within the study area for 2014, 2015, and 2016. A total of over 120 plot level corn yield were used for validation, and the overall average accuracy was 87%, which statistically justified the model's capability to estimate plot-level corn yield. Additionally, the proposed model was applied to the impact estimation by examining the changes in corn yield

Larval diet affects mosquito development and permissiveness to Plasmodium infection

OpenAIRE

Gendrin, MEM; Christophides; Linenberg, Inbar

2016-01-01

The larval stages of malaria vector mosquitoes develop in water pools, feeding mostly on microorganisms and environmental detritus. Richness in the nutrient supply to larvae influences the development and metabolism of larvae and adults. Here, we investigated the effects of larval diet on the development, microbiota content and permissiveness to Plasmodium of Anopheles coluzzii . We tested three fish diets often used to rear mosquitoes in the laboratory, including two pelleted diets, Dr. Clar...

Corn silk induces nitric oxide synthase in murine macrophages.

Science.gov (United States)

Kim, Kyung A; Choi, Sang Kyu; Choi, Hye Seon

2004-12-31

Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

Organogénesis durante el periodo larval en peces

OpenAIRE

Zavala-Leal, I; Dumas, Silvie; Peña Martínez, Renato

2011-01-01

La presencia de un periodo larval caracteriza a los peces con ontogenia indirecta. Este periodo de desarrollo implica una serie de transformaciones encaminadas a la adquisición de las características biológicas y ecológicas propias de la especie; y en muchos casos culmina con cambios de distribución y hábitos alimenticios. El periodo larval incluye cuatro estadios de desarrollo: larva vitelina, larva pre-flexión, larva flexión y larva post-flexión. Cada estadio de desarrollo presenta caracter...

Does white clover (Trifolium repens abundance in temperate pastures determine Sitona obsoletus (Coleoptera: Curculionidae larval populations?

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Mark Richard McNeill

2016-09-01

Full Text Available To determine if host plant abundance determined the size of clover root weevil (CRW Sitona obsoletus larval populations, a study was conducted over four years in plots sown in ryegrass (Lolium perenne (cv. Nui sown at either 6 or 30 kg/ha and white clover (Trifolium repens sown at a uniform rate of 8 kg/ha. This provided a range of % white clover content to investigate CRW population establishment and impacts on white clover survival. Larval sampling was carried out in spring (October when larval densities are near their spring peak at Lincoln (Canterbury, New Zealand with % clover measured in autumn (April and spring (September of each year. Overall, mean larval densities measured in spring 2012, 2013, 2014 and 2015 were 310, 38, 59 and 31 larvae m-2, respectively. There was a significant decline in larval populations between 2012 and 2013, but spring populations were relatively uniform thereafter. The mean % white clover measured in autumns of 2012 to 2015 was 17, 10, 3 and 11%, respectively. In comparison, mean spring % white clover from 2012 to 2015, averaged c. 5% each year. Analysis relating spring (October larval populations to % white clover measured in each plot in autumn (April found the 2012 larval population to be statistically significantly larger in the ryegrass 6 kg/ha plots than 30 kg/ha plots. Thereafter, sowing rate had no significant effect on larval populations. From 2013 to 2015, spring larval populations had a negative relationship with the previous autumn % white clover with the relationship highly significant for the 2014 data. When CRW larval populations in spring 2013 to 2015 were predicted from the 2013 to 2015 autumn % white clover, respectively, based on their positive relationship in 2012, the predicted densities were substantially larger than those observed. Conversely, when 2015 spring larval data and % clover was regressed against 2012-2014 larval populations, observed densities tended to be higher than predicted

Does White Clover (Trifolium repens) Abundance in Temperate Pastures Determine Sitona obsoletus (Coleoptera: Curculionidae) Larval Populations?

Science.gov (United States)

McNeill, Mark R; van Koten, Chikako; Cave, Vanessa M; Chapman, David; Hodgson, Hamish

2016-01-01

To determine if host plant abundance determined the size of clover root weevil (CRW) Sitona obsoletus larval populations, a study was conducted over 4 years in plots sown in ryegrass ( Lolium perenne ) (cv. Nui) sown at either 6 or 30 kg/ha and white clover ( Trifolium repens ) sown at a uniform rate of 8 kg/ha. This provided a range of % white clover content to investigate CRW population establishment and impacts on white clover survival. Larval sampling was carried out in spring (October) when larval densities are near their spring peak at Lincoln (Canterbury, New Zealand) with % clover measured in autumn (April) and spring (September) of each year. Overall, mean larval densities measured in spring 2012-2015 were 310, 38, 59, and 31 larvae m -2 , respectively. There was a significant decline in larval populations between 2012 and 2013, but spring populations were relatively uniform thereafter. The mean % white clover measured in autumns of 2012 to 2015 was 17, 10, 3, and 11%, respectively. In comparison, mean spring % white clover from 2012 to 2015, averaged c. 5% each year. Analysis relating spring (October) larval populations to % white clover measured in each plot in autumn (April) found the 2012 larval population to be statistically significantly larger in the ryegrass 6 kg/ha plots than 30 kg/ha plots. Thereafter, sowing rate had no significant effect on larval populations. From 2013 to 2015, spring larval populations had a negative relationship with the previous autumn % white clover with the relationship highly significant for the 2014 data. When CRW larval populations in spring 2013 to 2015 were predicted from the 2013 to 2015 autumn % white clover, respectively, based on their positive relationship in 2012, the predicted densities were substantially larger than those observed. Conversely, when 2015 spring larval data and % clover was regressed against 2012-2014 larval populations, observed densities tended to be higher than predicted, but the numbers

Domestic Larval Control Practices and Malaria Prevalence among Under-Five Children in Burkina Faso.

Directory of Open Access Journals (Sweden)

Souleymane Diabaté

Full Text Available Larval source management has contributed to malaria decline over the past years. However, little is known about the impact of larval control practices undertaken at the household level on malaria transmission.The study was conducted in Kaya health district after the 2010 mass distribution of insecticide treated-nets and the initiation of malaria awareness campaigns in Burkina Faso. The aim was to (i estimate the level of domestic larval control practices (cleaning of the house and its surroundings, eradication of larval sources, and elimination of hollow objects that might collect water; (ii identify key determinants; and (iii explore the structural relationships between these practices, participation in awareness-raising activities and mothers' knowledge/attitudes/practices, and malaria prevalence among under-five children.Overall, 2004 households were surveyed and 1,705 under-five children were examined. Half of the mothers undertook at least one action to control larval proliferation. Mothers who had gone to school had better knowledge about malaria and were more likely to undertake domestic larval control practices. Living in highly exposed rural areas significantly decreased the odds of undertaking larval control actions. Mothers' participation in malaria information sessions increased the adoption of vector control actions and bednet use. Malaria prevalence was statistically lower among children in households where mothers had undertaken at least one vector control action or used bed-nets. There was a 0.16 standard deviation decrease in malaria prevalence for every standard deviation increase in vector control practices. The effect of bednet use on malaria prevalence was of the same magnitude.Cleaning the house and its surroundings, eradicating breeding sites, and eliminating hollow objects that might collect water play a substantial role in preventing malaria among under-five. There is a need for national malaria control programs to

The improvement of corn starch isolation process by gamma irradiation

International Nuclear Information System (INIS)

Byun, M.W.; Kang, I.J.; Kwon, J.H.; Lee, S.J.; Kim, S.K.

1995-01-01

Gamma irradiation was applied to non-glutinous and glutinous corns for improving starch isolation process. No significant changes in proximate composition of corn grains were observed by gamma irradiation. Irradiation at 1 and 5 kGy was effective for sterilizing all contaminated microorganisms of non-glutinous and glutinous corns, respectively. The moisture-uptake rate constants were increased in proportional to the steeping temperature and applied irradiation dose level. The irradiation efficacy on water absorption properties was also recognized in the corns stored for six months at room temperature. The combined use of gamma irradiation with sulfur dioxide solution was very effective for reducing steeping time. The starch yield gradually increased as irradiation dose levels increased. At 2 kGy, the sarch yield of non-glutinous and glutinous corns increased by 38% and 27%, respectively. No significant difference in Hunter's color value was observed between the starches isolated from nonirradiated and irradiated corn grains

Aracnidae diversity in soil cultivated with corn (Zea mays

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Lígia Vanessa da Silva

2014-09-01

Full Text Available Studies carried out on the diversity and abundance of spiders may provide a rich information base on the degree of integrity of agricultural systems where they are found. In transgenic corn, Bacillus thuringiensis proteins are expressed in great amounts in plant tissues and may affect arthropod communities. Thus, the main goal of this work was to identify the spider diversity associated to transgenic and conventional corn hybrids. Pitfall collections were performed in conventional and transgenic corn plots during the 2010/2011 crop season, at the experimental field of the Agronomy Course of the University of Cruz Alta, RS. A total of 559 spiders were collected, from which 263 were adults and 296 young individuals. In the transgenic corn 266 spiders were collected and in the conventional one 293. Eleven families were determined and the adult individuals grouped in 27 morphospecies. Families with the largest number of representatives were Linyphiidae (29.70%, Theridiidae (5.72% and Lycosidae (5.01%. The most abundant morphospecies were Lyniphiidae sp. with 77 individuals, Erigone sp. with 40 individuals, Lynyphiidae sp. with 33 individuals, Theridiidae sp. with 21 individuals, Lycosa erythrognatha with 14 individuals and Lycosidae sp. with 13 individuals. The Shannon Diversity Index was higher for transgenic corn (H” =1.01 in February and smaller (H’=0.54 in the December collection in the conventional corn, and the Margaleff Richness Index showed higher diversity in December and February for the conventional corn (M=18.3, and smaller diversity for the transgenic corn in November (M=11.3. Families were classified in five guilds; two weavers: Irregular web builders and sheet web builders, and three hunter guilds: Night soil runners, ambush spiders and aerial night runners. The relative proportion of the spiders morphospecies found in this research, as well as the guilds, suggest that this group may not have been affected by the genetically

Effects of replacing conventional corn silage with BMR corn silage

Science.gov (United States)

Previous research has shown that the (lignin reducing) brown mid-rib mutation in corn silage, which increases in vitro fiber digestibility, does not always improve fiber digestibility when fed as part of a TMR; however, feed intake and milk production are increased. The objectives of this experiment...

Isolation and culture of larval cells from C. elegans.

Directory of Open Access Journals (Sweden)

Sihui Zhang

Full Text Available Cell culture is an essential tool to study cell function. In C. elegans the ability to isolate and culture cells has been limited to embryonically derived cells. However, cells or blastomeres isolated from mixed stage embryos terminally differentiate within 24 hours of culture, thus precluding post-embryonic stage cell culture. We have developed an efficient and technically simple method for large-scale isolation and primary culture of larval-stage cells. We have optimized the treatment to maximize cell number and minimize cell death for each of the four larval stages. We obtained up to 7.8×10(4 cells per microliter of packed larvae, and up to 97% of adherent cells isolated by this method were viable for at least 16 hours. Cultured larval cells showed stage-specific increases in both cell size and multinuclearity and expressed lineage- and cell type-specific reporters. The majority (81% of larval cells isolated by our method were muscle cells that exhibited stage-specific phenotypes. L1 muscle cells developed 1 to 2 wide cytoplasmic processes, while L4 muscle cells developed 4 to 14 processes of various thicknesses. L4 muscle cells developed bands of myosin heavy chain A thick filaments at the cell center and spontaneously contracted ex vivo. Neurons constituted less than 10% of the isolated cells and the majority of neurons developed one or more long, microtubule-rich protrusions that terminated in actin-rich growth cones. In addition to cells such as muscle and neuron that are high abundance in vivo, we were also able to isolate M-lineage cells that constitute less than 0.2% of cells in vivo. Our novel method of cell isolation extends C. elegans cell culture to larval developmental stages, and allows use of the wealth of cell culture tools, such as cell sorting, electrophysiology, co-culture, and high-resolution imaging of subcellular dynamics, in investigation of post-embryonic development and physiology.

7 CFR 810.404 - Grades and grade requirements for corn.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for corn. 810.404... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Corn Principles Governing the Application of Standards § 810.404 Grades and grade requirements for corn. Grade Minimum test weight per...

Variation of biometric parameters in corn cobs under the influence of nitrogen fertilization

Science.gov (United States)

Gigel, Prisecaru; Florin, Sala

2017-07-01

Biometric parameters as elements of productivity on corn cobs, along with plant density per unit area (ha) are essential in achieving production. The influence of differentiated fertilization with nitrogen was evaluated at the level of productivity elements on corn cobs, Andreea hybrid. Biometric parameters of the corn cobs (total length - L; usable length - l; uncoated length with corn kernels - lu; diameter at the base - Db, middle - Dm, and top of the corn cobs - Dt; corn cob weight - Cw, grain weight - Gw) were directly influenced by the doses of nitrogen. Regression analysis has facilitated the prediction of grain weight as the main element of productivity under different statistical certainty based on nitrogen doses (R2 = 0.962, p<0.01), on the total length of corn cobs (R2 = 0.985, p<0.01), on the usable length of corn cobs (R2 = 0.996, p<<0.001), on the diameter at the base of corn cobs (R2 = 0.824, p<0.01), on the diameter at the middle of corn cobs (R2 = 0.807, p<0.01), on uncoated length with corn kernels (R2 = 0.624, p<0.01) and on the diameter at the top of the corn cobs (R2 = 0.384, p=0.015).

Redescription of the early larval stages of the pandalid shrimp Chlorotocus crassicornis (Decapoda: Caridea: Pandalidae).

Science.gov (United States)

Landeira, Jose M; Jiang, Guo-Chen; Chan, Tin-Yam; Shih, Tung-Wei; Gozález-Gordillo, J Ignacio

2015-09-07

The first four larval stages of the pandalid shrimp Chlorotocus crassicornis (A. Costa, 1871) are described and illustrated from laboratory-reared material obtained from ovigerous females collected in the southwestern Spain and south Taiwan. The second to fourth larval stages of this species are reported for the first time to science. Detailed examination of the first larval stages reveals that previous description misidentified some key larval characters which have prevented its identification in plankton samples. It is found that the zoeal morphology of Chlorotocus is not very different from other pandalid larvae, and in fact closely resembles Plesionika and Heterocarpus.

Maleic acid treatment of biologically detoxified corn stover liquor.

Science.gov (United States)

Kim, Daehwan; Ximenes, Eduardo A; Nichols, Nancy N; Cao, Guangli; Frazer, Sarah E; Ladisch, Michael R

2016-09-01

Elimination of microbial and enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases, and other soluble inhibitors were eliminated by biological detoxification. Corn stover at 20% (w/v) solids was LHW pretreated LHW (severity factor: 4.3). The 20% solids (w/v) pretreated corn stover derived liquor was recovered and biologically detoxified using the fungus Coniochaeta ligniaria NRRL30616. After maleic acid treatment, and using 5 filter paper units of cellulase/g glucan (8.3mg protein/g glucan), 73% higher cellulose conversion from corn stover was obtained for biodetoxified samples compared to undetoxified samples. This corresponded to 87% cellulose to glucose conversion. Ethanol production by yeast of pretreated corn stover solids hydrolysate was 1.4 times higher than undetoxified samples, with a reduction of 3h in the fermentation lag phase. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cornelis den Hartog: an outstanding aquatic ecologist

NARCIS (Netherlands)

Velde, van der G.; Brock, T.C.M.; Kempers, A.J.

1996-01-01

A survey is given of the work and life of Cornelis den Hartog up to the date in 1996 on which he retired from his position as a professor at the University of Nijmegen. Cornelis (Kees) den Hartog made important contributions to aquatic ecology in the widest sense, e.G. On brackish water typology,

Rapid effects of marine reserves via larval dispersal.

Directory of Open Access Journals (Sweden)

Richard Cudney-Bueno

Full Text Available Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs, with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest.

Corn fiber hulls as a food additive or animal feed

Science.gov (United States)

Abbas, Charles; Beery, Kyle E.; Cecava, Michael J.; Doane, Perry H.

2010-12-21

The present invention provides a novel animal feed or food additive that may be made from thermochemically hydrolyzed, solvent-extracted corn fiber hulls. The animal feed or food additive may be made, for instance, by thermochemically treating corn fiber hulls to hydrolyze and solubilize the hemicellulose and starch present in the corn fiber hulls to oligosaccharides. The residue may be extracted with a solvent to separate the oil from the corn fiber, leaving a solid residue that may be prepared, for instance by aggolmerating, and sold as a food additive or an animal feed.

Influência da alimentação de Anagasta kuehniella Zeller(Lepidoptera: Pyralidae no desenvolvimento de Ceraeochrysa cubana Hagen (Neuroptera: Chrysopidae

Directory of Open Access Journals (Sweden)

Gilmar Nunes

2017-04-01

Abstract. Aimed to evaluate the biological development of Ceraeochrysa cubana Hagen immature stages fed on eggs of the mothsubmitted to different food substrates with ingredients on different concentrations (%: Corn flour (50% + Wheat flour (50% + Brewer’s yeast (3%; Transgenic corn flour (50% + Wheat flour (50% + Brewer’s yeast (3%; Breadcrumbs (97% + Brewer’s yeast (3%; Breadcrumbs (48.5% + Wheat flour (48.5% + Brewer’s yeast (3%; Rice flour (97% + Brewer’s yeast (3%; Rice flour (48.5% + Wheat flour (48.5 % + Brewer’s yeast (3%; Oatmeal (97% + Brewer’s yeast (3%; Oatmeal (48.5% + Wheat flour (48.5% + Brewer’s yeast (3%. We evaluated the period of each larval stage, complete larval period, pre pupal+pupal period, and larva to adulthood period, larval and pupal feasibility. Diets with oatmeal provided for moth promote greater time for the predator reach adulthood, with rice flour low sex ratio and with breadcrumbs low pupal feasibility. Diets formulated with corn flours + brewer’s yeast are most recommended for Ephestia kuehniella Zeller, aiming C. cubana mass rearing.

Corn Drying with Zeolite in The Fluidized Bed Dryer under Medium Temperature

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Mohamad Djaeni

2013-08-01

Full Text Available Drying is an important step to find high quality of corn. Based on Standard of National Industry, populer as SNI, number 01-3920-1995, the corn was well stored at moisture content 14% or below (wet basis. However, conventional corn drying dealed with in-efficient energy process and corn quality degradation. This research evaluated the performance of corn drying assisted by zeolite as moisture adsorbent. In this process, the zeolite and corn were placed in the dryer fluidized by warm air as drying medium under 40 - 50oC. The air evaporated water product from corn, and at same time the zeolite adsorbed moisture in air. So, the relative humidity of air in dryer can be kept low in which enhanced the driving force for drying. Beside that, the moisture adsoprtion by zeolite was exothermic process that can supply the energy for drying or keep the dryer temperature. Thus, the drying rate can be faster. This work foccussed to observe the effect of drying temperature, air velocity, and corn to zeolite ratio on drying time as well as corn quality. As indicators, the drying rate was estimated and the proxymates content such as protein, fat, and carbohydrate content were analyzed. The results showed that compared with conventional fluidised bed dryer, corn drying with zeolite, can speed up drying time as well as improving the constant of drying rate. In addition, the corn proximate nutrition content can be well retained. At operating temperature 40oC, air velocity 9 m.s-1, and zeolite to corn ratio 1:2, the drying time can be 60 minutes shorter compared to that without zeolite.

Effect of γ-ray irradiation on alcohol production from corn

International Nuclear Information System (INIS)

Han, Y.W.; Cho, Y.K.; Ciegler, A.

1983-01-01

Cracked corn was irradiated with γ rays at 0-100 Mrad and the effects of the irradiation on sugar yield, susceptibility to enzymatic hydrolysis of starch, yeast growth, and alcohol production were studied. Gamma irradiation at 50 Mrad or greater produced a considerable amount of reducing sugar but little glucose. At lower dosages, γ irradiation significantly increased the susceptibility of corn starch to enzymatic hydrolysis, but dosages of 50 Mrad or greater decomposed the starch molecules as indicated by the reduction in iodine uptake. About 12.5% reducing sugar was produced by amylase treatment of uncooked, irradiated corn. This amount exceeded the level of sugar produced from cooked (gelatinized) corn by the same enzyme treatment. The yeast numbers in submerged cultivation were lower on a corn substrate that was irradiated at 50 Mrad or greater compared to that on an unirradiated control. About the same level of alcohol was produced on uncooked, irradiated (10 5 - 10 6 rad) corn as from cooked (121 degrees C for 30 min) corn. Therefore, the conventional cooking process for gelatinization of starch prior to its saccharification can be eliminated by irradiation. Irradiation also eliminated the necessity of sterilization of the medium and reduced the viscosity of high levels of substrate in the fermentation broth. (Refs. 10)

21 CFR 358.510 - Corn and callus remover active ingredients.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Corn and callus remover active ingredients. 358.510 Section 358.510 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... USE Corn and Callus Remover Drug Products § 358.510 Corn and callus remover active ingredients. The...

Volatility spillovers in China’s crude oil, corn and fuel ethanol markets

International Nuclear Information System (INIS)

Haixia, Wu; Shiping, Li

2013-01-01

Price volatility spillovers among China’s crude oil, corn and fuel ethanol markets are analyzed based on weekly price data from September 5, 2003 to August 31, 2012, employing the univariate EGARCH model and the BEKK-MVGARCH model, respectively. The empirical results indicate a higher interaction among crude oil, corn and fuel ethanol markets after September, 2008. In the overall sample period, the results simultaneously provide strong evidence that there exist unidirectional spillover effects from the crude oil market to the corn and fuel ethanol markets, and double-directional spillovers between the corn market and the fuel ethanol market. However, the spillover effects from the corn and fuel ethanol markets to the crude oil market are not significant. -- Highlights: •Employing univariate EGARCH model and BEKK-MVGARCH model, respectively. Unidirectional spillover effects from crude oil market to corn and fuel ethanol markets. •Double-directional spillovers between corn market and fuel ethanol market. •The spillover effects from corn and fuel ethanol markets to crude oil market are not significant. •The empirical results indicate a higher interaction among crude oil, corn and fuel ethanol markets after September, 2008

Expression of Calmodulin and Myosin Light Chain Kinase during Larval Settlement of the Barnacle Balanus amphitrite

KAUST Repository

Chen, Zhang-Fan; Wang, Hao; Matsumura, Kiyotaka; Qian, Pei-Yuan

2012-01-01

Barnacles are one of the most common organisms in intertidal areas. Their life cycle includes seven free-swimming larval stages and sessile juvenile and adult stages. The transition from the swimming to the sessile stages, referred to as larval settlement, is crucial for their survivor success and subsequent population distribution. In this study, we focused on the involvement of calmodulin (CaM) and its binding proteins in the larval settlement of the barnacle, Balanus (= Amphibalanus) amphitrite. The full length of CaM gene was cloned from stage II nauplii of B. amphitrite (referred to as Ba-CaM), encoding 149 amino acid residues that share a high similarity with published CaMs in other organisms. Quantitative real-time PCR showed that Ba-CaM was highly expressed in cyprids, the stage at which swimming larvae are competent to attach and undergo metamorphosis. In situ hybridization revealed that the expressed Ba-CaM gene was localized in compound eyes, posterior ganglion and cement glands, all of which may have essential functions during larval settlement. Larval settlement assays showed that both the CaM inhibitor compound 48/80 and the CaM-dependent myosin light chain kinase (MLCK) inhibitor ML-7 effectively blocked barnacle larval settlement, whereas Ca 2+/CaM-dependent kinase II (CaMKII) inhibitors did not show any clear effects. The subsequent real-time PCR assay showed a higher expression level of Ba-MLCK gene in larval stages than in adults, suggesting an important role of Ba-MLCK gene in larval development and competency. Overall, the results suggest that CaM and CaM-dependent MLCK function during larval settlement of B. amphitrite. © 2012 Chen et al.

Expression of Calmodulin and Myosin Light Chain Kinase during Larval Settlement of the Barnacle Balanus amphitrite

KAUST Repository

Chen, Zhang-Fan

2012-02-13

Barnacles are one of the most common organisms in intertidal areas. Their life cycle includes seven free-swimming larval stages and sessile juvenile and adult stages. The transition from the swimming to the sessile stages, referred to as larval settlement, is crucial for their survivor success and subsequent population distribution. In this study, we focused on the involvement of calmodulin (CaM) and its binding proteins in the larval settlement of the barnacle, Balanus (= Amphibalanus) amphitrite. The full length of CaM gene was cloned from stage II nauplii of B. amphitrite (referred to as Ba-CaM), encoding 149 amino acid residues that share a high similarity with published CaMs in other organisms. Quantitative real-time PCR showed that Ba-CaM was highly expressed in cyprids, the stage at which swimming larvae are competent to attach and undergo metamorphosis. In situ hybridization revealed that the expressed Ba-CaM gene was localized in compound eyes, posterior ganglion and cement glands, all of which may have essential functions during larval settlement. Larval settlement assays showed that both the CaM inhibitor compound 48/80 and the CaM-dependent myosin light chain kinase (MLCK) inhibitor ML-7 effectively blocked barnacle larval settlement, whereas Ca 2+/CaM-dependent kinase II (CaMKII) inhibitors did not show any clear effects. The subsequent real-time PCR assay showed a higher expression level of Ba-MLCK gene in larval stages than in adults, suggesting an important role of Ba-MLCK gene in larval development and competency. Overall, the results suggest that CaM and CaM-dependent MLCK function during larval settlement of B. amphitrite. © 2012 Chen et al.

Contributions of Anopheles larval control to malaria suppression in tropical Africa: review of achievements and potential.

Science.gov (United States)

Walker, K; Lynch, M

2007-03-01

Malaria vector control targeting the larval stages of mosquitoes was applied successfully against many species of Anopheles (Diptera: Culicidae) in malarious countries until the mid-20th Century. Since the introduction of DDT in the 1940s and the associated development of indoor residual spraying (IRS), which usually has a more powerful impact than larval control on vectorial capacity, the focus of malaria prevention programmes has shifted to the control of adult vectors. In the Afrotropical Region, where malaria is transmitted mainly by Anopheles funestus Giles and members of the Anopheles gambiae Giles complex, gaps in information on larval ecology and the ability of An. gambiae sensu lato to exploit a wide variety of larval habitats have discouraged efforts to develop and implement larval control strategies. Opportunities to complement adulticiding with other components of integrated vector management, along with concerns about insecticide resistance, environmental impacts, rising costs of IRS and logistical constraints, have stimulated renewed interest in larval control of malaria vectors. Techniques include environmental management, involving the temporary or permanent removal of anopheline larval habitats, as well as larviciding with chemical or biological agents. This present review covers large-scale trials of anopheline larval control methods, focusing on field studies in Africa conducted within the past 15 years. Although such studies are limited in number and scope, their results suggest that targeting larvae, particularly in human-made habitats, can significantly reduce malaria transmission in appropriate settings. These approaches are especially suitable for urban areas, where larval habitats are limited, particularly when applied in conjunction with IRS and other adulticidal measures, such as the use of insecticide treated bednets.

Social coercion of larval development in an ant species.

Science.gov (United States)

Villalta, Irene; Amor, Fernando; Cerdá, Xim; Boulay, Raphaël

2016-04-01

Ants provide one of the best examples of the division of labor in animal societies. While the queens reproduce, workers generally refrain from laying eggs and dedicate themselves exclusively to domestic tasks. In many species, the small diploid larvae are bipotent and can develop either into workers or queens depending mostly on environmental cues. This generates a conflicting situation between the adults that tend to rear a majority of larvae into workers and the larvae whose individual interest may be to develop into reproductive queens. We tested the social regulation of larval caste fate in the fission-performing ant Aphaenogaster senilis. We first observed interactions between resident workers and queen- and worker-destined larvae in presence/absence of the queen. The results show that workers tend to specifically eliminate queen-destined larvae when the queen is present but not when she is absent or imprisoned in a small cage allowing for volatile pheromone exchanges. In addition, we found that the presence of already developed queen-destined larvae does not inhibit the development of younger still bipotent larvae into queens. Finally, we analyzed the cuticular hydrocarbon profiles of queen- and worker-destined larvae and found no significant quantitative or qualitative difference. Interestingly, the total amount of hydrocarbons on both larval castes is extremely low, which lends credence on the chemical insignificance hypothesis of larval ants. Overall, our results suggest that workers control larval development and police larvae that would develop into queens instead of workers. Such policing behavior is similar in many aspects to what is known of worker policing among adults.

Social coercion of larval development in an ant species

Science.gov (United States)

Villalta, Irene; Amor, Fernando; Cerdá, Xim; Boulay, Raphaël

2016-04-01

Ants provide one of the best examples of the division of labor in animal societies. While the queens reproduce, workers generally refrain from laying eggs and dedicate themselves exclusively to domestic tasks. In many species, the small diploid larvae are bipotent and can develop either into workers or queens depending mostly on environmental cues. This generates a conflicting situation between the adults that tend to rear a majority of larvae into workers and the larvae whose individual interest may be to develop into reproductive queens. We tested the social regulation of larval caste fate in the fission-performing ant Aphaenogaster senilis. We first observed interactions between resident workers and queen- and worker-destined larvae in presence/absence of the queen. The results show that workers tend to specifically eliminate queen-destined larvae when the queen is present but not when she is absent or imprisoned in a small cage allowing for volatile pheromone exchanges. In addition, we found that the presence of already developed queen-destined larvae does not inhibit the development of younger still bipotent larvae into queens. Finally, we analyzed the cuticular hydrocarbon profiles of queen- and worker-destined larvae and found no significant quantitative or qualitative difference. Interestingly, the total amount of hydrocarbons on both larval castes is extremely low, which lends credence on the chemical insignificance hypothesis of larval ants. Overall, our results suggest that workers control larval development and police larvae that would develop into queens instead of workers. Such policing behavior is similar in many aspects to what is known of worker policing among adults.

Larval traits carry over to affect post-settlement behaviour in a common coral reef fish.

Science.gov (United States)

Dingeldein, Andrea L; White, J Wilson

2016-07-01

Most reef fishes begin life as planktonic larvae before settling to the reef, metamorphosing and entering the benthic adult population. Different selective forces determine survival in the planktonic and benthic life stages, but traits established in the larval stage may carry over to affect post-settlement performance. We tested the hypothesis that larval traits affect two key post-settlement fish behaviours: social group-joining and foraging. Certain larval traits of reef fishes are permanently recorded in the rings in their otoliths. In the bluehead wrasse (Thalassoma bifasciatum), prior work has shown that key larval traits recorded in otoliths (growth rate, energetic condition at settlement) carry over to affect post-settlement survival on the reef, with higher-larval-condition fish experiencing less post-settlement mortality. We hypothesized that this selective mortality is mediated by carry-over effects on post-settlement antipredator behaviours. We predicted that better-condition fish would forage less and be more likely to join groups, both behaviours that would reduce predation risk. We collected 550 recently settled bluehead wrasse (Thalassoma bifasciatum) from three reef sites off St. Croix (USVI) and performed two analyses. First, we compared each settler's larval traits to the size of its social group to determine whether larval traits influenced group-joining behaviour. Secondly, we observed foraging behaviour in a subset of grouped and solitary fish (n = 14) for 1-4 days post-settlement. We then collected the fish and tested whether larval traits influenced the proportion of time spent foraging. Body length at settlement, but not condition, affected group-joining behaviour; smaller fish were more likely to remain solitary or in smaller groups. However, both greater length and better condition were associated with greater proportions of time spent foraging over four consecutive days post-settlement. Larval traits carry over to affect post

Increasing harvest maturity of whole-plant corn silage reduces methane

NARCIS (Netherlands)

Hatew, B.; Bannink, A.; Laar, van H.; Jonge, de L.H.; Dijkstra, J.

2016-01-01

The objective of this study was to investigate the effects of increasing maturity of whole-plant corn at harvest on CH4 emissions by dairy cows consuming corn silage (CS) based diets. Whole-plant corn was harvested at a very early [25% dry matter (DM); CS25], early (28% DM; CS28), medium (32% DM;

7 CFR 319.24-4 - Notice of arrival of corn by permittee.

Science.gov (United States)

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Notice of arrival of corn by permittee. 319.24-4... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Corn Diseases Regulations Governing Entry of Indian Corn Or Maize § 319.24-4 Notice of arrival of corn by permittee. Immediately upon...

Circatrigintan instead of lunar periodicity of larval release in a brooding coral species.

Science.gov (United States)

Linden, Bart; Huisman, Jef; Rinkevich, Baruch

2018-04-04

Larval release by brooding corals is often assumed to display lunar periodicity. Here, we show that larval release of individual Stylophora pistillata colonies does not comply with the assumed tight entrainment by the lunar cycle, and can better be classified as a circatrigintan pattern. The colonies exhibited three distinct reproductive patterns, characterized by short intervals, long intervals and no periodicity between reproductive peaks, respectively. Cross correlation between the lunar cycle and larval release of the periodic colonies revealed an approximately 30-day periodicity with a variable lag of 5 to 10 days after full moon. The observed variability indicates that the lunar cycle does not provide a strict zeitgeber. Other factors such as water temperature and solar radiation did not correlate significantly with the larval release. The circatrigintan patterns displayed by S. pistillata supports the plasticity of corals and sheds new light on discussions on the fecundity of brooding coral species.

Corn Clubs: Building the Foundation for Agricultural and Extension Education

Science.gov (United States)

Uricchio, Cassandra; Moore, Gary; Coley, Michael

2013-01-01

Corn clubs played an important role in improving agriculture at the turn of the 20th century. Corn clubs were local organizations consisting of boys who cultivated corn on one acre of land under the supervision of a local club leader. The purpose of this historical research study was to document the organization, operation, and outcomes of corn…

19 CFR 10.57 - Certified seed potatoes, and seed corn or maize.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Certified seed potatoes, and seed corn or maize... Provisions Potatoes, Corn, Or Maize § 10.57 Certified seed potatoes, and seed corn or maize. Claim for classification as seed potatoes under subheading 0701.10.00, as seed corn (maize) under subheading 1005.10...

Diel variation of larval fish abundance in the Amazon and Rio Negro

Directory of Open Access Journals (Sweden)

ARAUJO-LIMA C. A. R. M.

2001-01-01

Full Text Available Many streams and large rivers present higher ichthyoplankton densities at night. However, in some rivers this does not occur and larvae are equally abundant during the day. Larval drift diel variation is an important information for planning sampling programs for evaluating larval distribution and production. The aim of this study was to test whether the abundance of larval fish was different at either period. We tested it by comparing day and night densities of characiform, clupeiform and siluriform larvae during five years in the Amazon and one year in Rio Negro. We found that larvae of three species of characiform and larvae of siluriform were equally abundant during day and night in the Amazon. Conversely, the catch of Pellona spp. larvae was significantly higher during the day. In Rio Negro, however, larval abundance was higher during the night. These results imply that day samplings estimate adequately the abundance of these characiform and siluriform larvae in the Amazon, but not Pellona larvae. Evaluations of larved densities of Rio Negro will have to consider night sampling.

Diel variation of larval fish abundance in the Amazon and Rio Negro

Directory of Open Access Journals (Sweden)

C. A. R. M. ARAUJO-LIMA

Full Text Available Many streams and large rivers present higher ichthyoplankton densities at night. However, in some rivers this does not occur and larvae are equally abundant during the day. Larval drift diel variation is an important information for planning sampling programs for evaluating larval distribution and production. The aim of this study was to test whether the abundance of larval fish was different at either period. We tested it by comparing day and night densities of characiform, clupeiform and siluriform larvae during five years in the Amazon and one year in Rio Negro. We found that larvae of three species of characiform and larvae of siluriform were equally abundant during day and night in the Amazon. Conversely, the catch of Pellona spp. larvae was significantly higher during the day. In Rio Negro, however, larval abundance was higher during the night. These results imply that day samplings estimate adequately the abundance of these characiform and siluriform larvae in the Amazon, but not Pellona larvae. Evaluations of larved densities of Rio Negro will have to consider night sampling.

A review of postfeeding larval dispersal in blowflies: implications for forensic entomology

Science.gov (United States)

Gomes, Leonardo; Godoy, Wesley Augusto Conde; von Zuben, Claudio José

2006-05-01

Immature and adult stages of blowflies are one of the primary invertebrate consumers of decomposing animal organic matter. When the food supply is consumed or when the larvae complete their development and migrate prior to the total removal of the larval substrate, they disperse to find adequate places for pupation, a process known as postfeeding larval dispersal. Several important ecological and physiological aspects of this process were studied since the work by Green (Ann Appl Biol 38:475, 1951) 50 years ago. An understanding of postfeeding larval dispersal can be useful for determining the postmortem interval (PMI) of human cadavers in legal medicine, particularly because this interval may be underestimated if older dispersing larvae or those that disperse longer, faster, and deeper are not taken into account. In this article, we review the process of postfeeding larval dispersal and its implications for legal medicine, in particular showing that aspects such as burial behavior and competition among species of blowflies can influence this process and consequently, the estimation of PMI.

Short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish (Danio rerio).

Science.gov (United States)

Cao, Fangjie; Wu, Peizhuo; Huang, Lan; Li, Hui; Qian, Le; Pang, Sen; Qiu, Lihong

2018-05-01

Previous study indicated that azoxystrobin had high acute toxicity to zebrafish, and larval zebrafish were more sensitive to azoxystrobin than adult zebrafish. The objective of the present study was to investigate short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish. After zebrafish embryos and adults were exposed to 0.01, 0.05 and 0.20 mg/L azoxystrobin (equal to 25, 124 and 496 nM azoxystrobin, respectively) for 8 days, the lethal effect, physiological responses, liver histology, mitochondrial ultrastructure, and expression alteration of genes related to mitochondrial respiration, oxidative stress, cell apoptosis and innate immune response were determined. The results showed that there was no significant effect on larval and adult zebrafish after exposure to 0.01 mg/L azoxystrobin. However, increased ROS, MDA concentration and il1b in larval zebrafish, as well as increased il1b, il8 and cxcl-c1c in adult zebrafish were induced after exposure to 0.05 mg/L azoxystrobin. Reduced mitochondrial complex III activity and ATP concentration, increased SOD activity, ROS and MDA concentration, decreased cytb, as well as increased sod1, sod2, cat, il1b, il8 and cxcl-c1c were observed both in larval and adult zebrafish after exposure to 0.20 mg/L azoxystrobin; meanwhile, increased p53, bax, apaf1 and casp9, alteration of liver histology and mitochondrial ultrastructure in larval zebrafish, and alteration of mitochondrial ultrastructure in adult zebrafish were also induced. The results demonstrated that azoxytrobin induced short-term developmental effects on larval zebrafish and adult zebrafish, including mitochondrial dysfunction, oxidative stress, cell apoptosis and innate immune response. Statistical analysis indicated that azoxystrobin induced more negative effects on larval zebrafish, which might be the reason for the differences of developmental toxicity between larval and adult zebrafish caused by

Winter cover crop effect on corn seedling pathogens

Science.gov (United States)

Cover crops are an excellent management tool to improve the sustainability of agriculture. Winter rye cover crops have been used successfully in Iowa corn-soybean rotations. Unfortunately, winter rye cover crops occasionally reduce yields of the following corn crop. We hypothesize that one potential...

Simulation of corn yields and parameters uncertainties analysis in Hebei and Sichuang, China

Science.gov (United States)

Fu, A.; Xue, Y.; Hartman, M. D.; Chandran, A.; Qiu, B.; Liu, Y.

2016-12-01

Corn is one of most important agricultural production in China. Research on the impacts of climate change and human activities on corn yields is important in understanding and mitigating the negative effects of environmental factors on corn yields and maintaining the stable corn production. Using climatic data, including daily temperature, precipitation, and solar radiation from 1948 to 2010, soil properties, observed corn yields, and farmland management information, corn yields in Sichuang and Hebei Provinces of China in the past 63 years were simulated using the Daycent model, and the results was evaluated using Root mean square errors, bias, simulation efficiency, and standard deviation. The primary climatic factors influencing corn yields were examined, the uncertainties of climatic factors was analyzed, and the uncertainties of human activity parameters were also studied by changing fertilization levels and cultivated ways. The results showed that: (1) Daycent model is capable to simulate corn yields in Sichuang and Hebei provinces of China. Observed and simulated corn yields have the similar increasing trend with time. (2) The minimum daily temperature is the primary factor influencing corn yields in Sichuang. In Hebei Province, daily temperature, precipitation and wind speed significantly affect corn yields.(3) When the global warming trend of original data was removed, simulated corn yields were lower than before, decreased by about 687 kg/hm2 from 1992 to 2010; When the fertilization levels, cultivated ways were increased and decreased by 50% and 75%, respectively in the Schedule file in Daycent model, the simulated corn yields increased by 1206 kg/hm2 and 776 kg/hm2, respectively, with the enhancement of fertilization level and the improvement of cultivated way. This study provides a scientific base for selecting a suitable fertilization level and cultivated way in corn fields in China.

Acondicionamiento de reproductores, desove y cultivo larval de Graus nigra (Philippi, 1887 (Kyphosidae: Girellinae Broodstock conditioning, spawning and larval culture of Graus nigra (Philippi, 1887 (Kyphosidae: Girellinae

Directory of Open Access Journals (Sweden)

Avelino Muñoz

2012-09-01

Full Text Available Se describen resultados sobre acondicionamiento reproductivo, desove y cultivo larval de Graus nigra ("vieja negra", "mulata". Peces adultos silvestres se recolectaron y se utilizaron como reproductores, los que al final del período de acondicionamiento alcanzaron el estado de maduración gonadal y desovaron en forma natural y espontánea. Los huevos fueron recolectados y después de 36 h de incubación eclosionaron, con una tasa de eclosión promedio de 60%. Las larvas recién eclosionadas midieron 2,9 ± 0,23 mm y alcanzaron el día 50 post-eclosión (PE una longitud total de 12,6 ± 0,37 mm. La sobrevivencia larval posterior a la eclosión fue entre 50,9 y 79,1% y al día 30 PE fue de 12,1%. El cultivo larval se desarrolló en estanques con suministro de agua de mar filtrada y esterilizada. Después de la reabsorción del saco vitelino se produjo el desarrollo del tracto digestivo y las larvas se alimentaron con dieta viva enriquecida con emulsión de ácidos grasos altamente insaturados. A los 35 días de cultivo se ofreció alimento artificial a las larvas cuyo tamano fue aumentando progresivamente a medida que progresó su desarrollo ontogénico. Se describe la evolución anatómica de las larvas y las relaciones morfométricas que representan su desarrollo; se caracteriza el patrón de crecimiento de las larvas hasta los 50 días post-eclosión y se discuten aspectos relacionados con la sobrevivencia larval y la introducción de mejoras para optimizar la producción de larvas y juveniles.In this study results related to reproductive conditioning, spawning and larval culture of Graus nigra ("vieja negra", "mulata" are given. Wild adult fishes were collected and used as brooders which at the end of the conditioning period reached gonadal maturation state and spawned naturally and spontaneously. Eggs were collected and after 36 hours of incubation they hatched at average rate of 60%. The hatched larvae measured 2.9 ± 0.23 mm and at day 50

Subchronic toxicity study of corn silk with rats.

Science.gov (United States)

Wang, Cuina; Zhang, Tiehua; Liu, Jun; Lu, Shuang; Zhang, Cheng; Wang, Erlei; Wang, Zuozhao; Zhang, Yan; Liu, Jingbo

2011-09-01

Corn silk is a traditional herbal medicine in China, which has been used in many parts of the world for the treatment of edema as well as for cystitis, gout, kidney stones, nephritis, prostatitis and similar ailments. However, there is little scientific evidence about its safety. As a part of its safety assessment, a subchronic toxicity was performed in this paper. The subchronic toxicity was investigated in male and female Wistar rats by dietary administration at concentrations of 0.5%, 2.0% and 8.0% (w/w) for 90 days. Overall health, body weight, food consumption, hematology, blood chemistry, organ weights, gross and microscopic appearance of tissues were compared between test and control groups. A number of significant differences were seen between groups, but none of them was considered to be adverse. Based on the present study, the no-observed-adverse-effect level (NOAEL) of corn silk is at least 8.0% which corresponds to a mean daily corn silk intake of approximately 9.354 and 10.308 g/day/kg body weight for males and females, respectively. The results obtained in the present study suggest that consumption of corn silk has no adverse effects and support the safety of corn silk for humans. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Potential economic losses to the US corn industry from aflatoxin contamination.

Science.gov (United States)

Mitchell, Nicole J; Bowers, Erin; Hurburgh, Charles; Wu, Felicia

2016-01-01

Mycotoxins, toxins produced by fungi that colonise food crops, can pose a heavy economic burden to the US corn industry. In terms of economic burden, aflatoxins are the most problematic mycotoxins in US agriculture. Estimates of their market impacts are important in determining the benefits of implementing mitigation strategies within the US corn industry, and the value of strategies to mitigate mycotoxin problems. Additionally, climate change may cause increases in aflatoxin contamination in corn, greatly affecting the economy of the US Midwest and all sectors in the United States and worldwide that rely upon its corn production. We propose two separate models for estimating the potential market loss to the corn industry from aflatoxin contamination, in the case of potential near-future climate scenarios (based on aflatoxin levels in Midwest corn in warm summers in the last decade). One model uses the probability of acceptance based on operating characteristic (OC) curves for aflatoxin sampling and testing, while the other employs partial equilibrium economic analysis, assuming no Type 1 or Type 2 errors, to estimate losses due to proportions of lots above the US Food and Drug Administration (USFDA) aflatoxin action levels. We estimate that aflatoxin contamination could cause losses to the corn industry ranging from US$52.1 million to US$1.68 billion annually in the United States, if climate change causes more regular aflatoxin contamination in the Corn Belt as was experienced in years such as 2012. The wide range represents the natural variability in aflatoxin contamination from year to year in US corn, with higher losses representative of warmer years.

Potential economic losses to the USA corn industry from aflatoxin contamination

Science.gov (United States)

Mitchell, N.J.; Bowers, E.; Hurburgh, C.; Wu, F.

2016-01-01

Mycotoxins, toxins produced by fungi that colonize food crops, can pose a heavy economic burden to the United States corn industry. In terms of economic burden, aflatoxins are the most problematic mycotoxins in US agriculture. Estimates of their market impacts are important in determining the benefits of implementing mitigation strategies within the US corn industry, and the value of strategies to mitigate mycotoxin problems. Additionally, climate change may cause increases in aflatoxin contamination in corn, greatly affecting the economy of the US Midwest and all sectors in the US and worldwide that rely upon its corn production. We propose two separate models for estimating the potential market loss to the corn industry from aflatoxin contamination, in the case of potential near-future climate scenarios (based on aflatoxin levels in Midwest corn in warm summers in the last decade). One model uses probability of acceptance based on operating characteristic (OC) curves for aflatoxin sampling and testing, while the other employs partial equilibrium economic analysis, assuming no Type 1 or Type 2 errors, to estimate losses due to proportions of lots above the US Food and Drug Administration (FDA) aflatoxin action levels. We estimate that aflatoxin contamination could cause losses to the corn industry ranging from $52.1 million to $1.68 billion annually in the United States, if climate change causes more regular aflatoxin contamination in the Corn Belt as was experienced in years such as 2012. The wide range represents the natural variability in aflatoxin contamination from year to year in US corn, with higher losses representative of warmer years. PMID:26807606

Chemical constituents and free radical scavenging activity of corn pollen collected from Apis mellifera hives compared to floral corn pollen at Nan, Thailand

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Chantarudee Atip

2012-04-01

Full Text Available Abstract Background Bee pollen is composed of floral pollen mixed with nectar and bee secretion that is collected by foraging honey (Apis sp. and stingless bees. It is rich in nutrients, such as sugars, proteins, lipids, vitamins and flavonoids, and has been ascribed antiproliferative, anti-allergenic, anti-angiogenic and free radical scavenging activities. This research aimed at a preliminary investigation of the chemical constituents and free radical scavenging activity in A. mellifera bee pollen. Methods Bee pollen was directly collected from A. mellifera colonies in Nan province, Thailand, in June, 2010, whilst floral corn (Zea mays L. pollen was collected from the nearby corn fields. The pollen was then sequentially extracted with methanol, dichloromethane (DCM and hexane, and each crude extract was tested for free radical scavenging activity using the DPPH assay, evaluating the percentage scavenging activity and the effective concentration at 50% (EC50. The most active crude fraction from the bee pollen was then further enriched for bioactive components by silica gel 60 quick and adsorption or Sephadex LH-20 size exclusion chromatography. The purity of all fractions in each step was observed by thin layer chromatography and the bioactivity assessed by the DPPH assay. The chemical structures of the most active fractions were analyzed by nuclear magnetic resonance. Results The crude DCM extract of both the bee corn pollen and floral corn pollen provided the highest active free radical scavenging activity of the three solvent extracts, but it was significantly (over 28-fold higher in the bee corn pollen (EC50 = 7.42 ± 0.12 μg/ml, than the floral corn pollen (EC50 = 212 ± 13.6% μg/ml. After fractionation to homogeneity, the phenolic hydroquinone and the flavone 7-O-R-apigenin were found as the minor and major bioactive compounds, respectively. Bee corn pollen contained a reasonably diverse array of nutritional components, including

Intercropping of corn with cowpea and bean: Biomass yield and ...

African Journals Online (AJOL)

STORAGESEVER

2008-11-19

Nov 19, 2008 ... Hand weeding by hoe was done once when the corn was app. 20 cm in height. Plots were harvested at the doughy stage of corn, cutting mid-rows of plots in order to avoid border effects, by removing at 4-5 cm height on 9 Sept.,. 2004 and 12 Sept., 2005, respectively. Corn was harvested from the middle 5.

Linking larval history to juvenile demography in the bicolor damselfish Stegastes partitus (Perciformes:Pomacentridae

Directory of Open Access Journals (Sweden)

Richard S Nemeth

2005-05-01

Full Text Available Otolith-based reconstructions of daily larval growth increments were used to examine the effect of variation in larval growth on size and age at settlement and post-settlement growth,survival and habitat preferences of juvenile bicolor damselfish (Stegastes partitus Poey.During August 1992 and 1994,newly settled S. partitus were collected from Montastraea coral heads and Porites rubble piles in Tague Bay,St.Croix,U.S. Virgin Islands (17 °45 ’ N,64 °42 ’ W.Daily lapillar otolith increments from each fish were counted and measured with Optimas image analysis software.S.partitus pelagic larval duration was 23.7 d in 1992 (n =70and 24.6 d in 1994 (n =38and larval age at settlement averaged 13.0 mm total length both years.Analysis of daily otolith increments demonstrated that variation in larval growth rates and size and age at settlement had no detectable effect on post-settlement survivorship but that larger larvae showed a preference for Montastraea coral at settlement.Late larval and early juvenile growth rates showed a significant positive relationship indicating that growth patterns established during the planktonic stage can span metamorphosis and continue into the benthic juvenile phase.Larval growth rates during the first two weeks post-hatching also had a strong effect on age to developmental competence (ability to undergo metamorphosisin both 1992 and 1994 with the fastest growing larvae being 8 d younger and 0.8 mm smaller at settlement than the slowest growing larvae.These differential growth rates in early stage larvae established trajectories toward larval developmental competence and may prove important in biogeographical studies of larval dispersal.Reconstruyendo aumentos diarios de otolitos se compará la variación en crecimiento larval sobre el tamaño y la edad de asentamiento,y el crecimiento post-acentamiento, sobrevivencia y preferencia de hábitat,del pez damisela bicolor (Stegastes partitus Poeyjoven.En agosto de 1992

Toward an understanding of the molecular mechanisms of barnacle larval settlement: A comparative transcriptomic approach

KAUST Repository

Chen, Zhang-Fan

2011-07-29

Background: The barnacle Balanus amphitrite is a globally distributed biofouler and a model species in intertidal ecology and larval settlement studies. However, a lack of genomic information has hindered the comprehensive elucidation of the molecular mechanisms coordinating its larval settlement. The pyrosequencing-based transcriptomic approach is thought to be useful to identify key molecular changes during larval settlement. Methodology and Principal Findings: Using 454 pyrosequencing, we collected totally 630,845 reads including 215,308 from the larval stages and 415,537 from the adults; 23,451 contigs were generated while 77,785 remained as singletons. We annotated 31,720 of the 92,322 predicted open reading frames, which matched hits in the NCBI NR database, and identified 7,954 putative genes that were differentially expressed between the larval and adult stages. Of these, several genes were further characterized with quantitative real-time PCR and in situ hybridization, revealing some key findings: 1) vitellogenin was uniquely expressed in late nauplius stage, suggesting it may be an energy source for the subsequent non-feeding cyprid stage; 2) the locations of mannose receptors suggested they may be involved in the sensory system of cyprids; 3) 20 kDa-cement protein homologues were expressed in the cyprid cement gland and probably function during attachment; and 4) receptor tyrosine kinases were expressed higher in cyprid stage and may be involved in signal perception during larval settlement. Conclusions: Our results provide not only the basis of several new hypotheses about gene functions during larval settlement, but also the availability of this large transcriptome dataset in B. amphitrite for further exploration of larval settlement and developmental pathways in this important marine species. © 2011 Chen et al.

Live Cell Imaging of Butterfly Pupal and Larval Wings In Vivo.

Science.gov (United States)

Ohno, Yoshikazu; Otaki, Joji M

2015-01-01

Butterfly wing color patterns are determined during the late larval and early pupal stages. Characterization of wing epithelial cells at these stages is thus critical to understand how wing structures, including color patterns, are determined. Previously, we successfully recorded real-time in vivo images of developing butterfly wings over time at the tissue level. In this study, we employed similar in vivo fluorescent imaging techniques to visualize developing wing epithelial cells in the late larval and early pupal stages 1 hour post-pupation. Both larval and pupal epithelial cells were rich in mitochondria and intracellular networks of endoplasmic reticulum, suggesting high metabolic activities, likely in preparation for cellular division, polyploidization, and differentiation. Larval epithelial cells in the wing imaginal disk were relatively large horizontally and tightly packed, whereas pupal epithelial cells were smaller and relatively loosely packed. Furthermore, larval cells were flat, whereas pupal cells were vertically elongated as deep as 130 μm. In pupal cells, many endosome-like or autophagosome-like structures were present in the cellular periphery down to approximately 10 μm in depth, and extensive epidermal feet or filopodia-like processes were observed a few micrometers deep from the cellular surface. Cells were clustered or bundled from approximately 50 μm in depth to deeper levels. From 60 μm to 80 μm in depth, horizontal connections between these clusters were observed. The prospective eyespot and marginal focus areas were resistant to fluorescent dyes, likely because of their non-flat cone-like structures with a relatively thick cuticle. These in vivo images provide important information with which to understand processes of epithelial cell differentiation and color pattern determination in butterfly wings.

Larval settlement: the role of surface topography for sessile coral reef invertebrates.

Science.gov (United States)

Whalan, Steve; Wahab, Muhammad A Abdul; Sprungala, Susanne; Poole, Andrew J; de Nys, Rocky

2015-01-01

For sessile marine invertebrates with complex life cycles, habitat choice is directed by the larval phase. Defining which habitat-linked cues are implicated in sessile invertebrate larval settlement has largely concentrated on chemical cues which are thought to signal optimal habitat. There has been less effort establishing physical settlement cues, including the role of surface microtopography. This laboratory based study tested whether surface microtopography alone (without chemical cues) plays an important contributing role in the settlement of larvae of coral reef sessile invertebrates. We measured settlement to tiles, engineered with surface microtopography (holes) that closely matched the sizes (width) of larvae of a range of corals and sponges, in addition to surfaces with holes that were markedly larger than larvae. Larvae from two species of scleractinian corals (Acropora millepora and Ctenactis crassa) and three species of coral reef sponges (Luffariella variabilis, Carteriospongia foliascens and Ircinia sp.,) were used in experiments. L. variabilis, A. millepora and C. crassa showed markedly higher settlement to surface microtopography that closely matched their larval width. C. foliascens and Ircinia sp., showed no specificity to surface microtopography, settling just as often to microtopography as to flat surfaces. The findings of this study question the sole reliance on chemical based larval settlement cues, previously established for some coral and sponge species, and demonstrate that specific physical cues (surface complexity) can also play an important role in larval settlement of coral reef sessile invertebrates.

The causes and unintended consequences of a paradigm shift in corn production practices

International Nuclear Information System (INIS)

Fausti, Scott W.

2015-01-01

Highlights: • Biotechnology adoption and the U.S. corn production system are causally linked. • U.S. agriculture and energy policy choices merged to incentivize U.S. corn production. • U.S. biofuel energy policy contributed to the adoption of Bt corn seed technology. • Policy alternatives to modify the corn-based ethanol production system are provided. - Abstract: Independent but simultaneously occurring changes in U.S. agricultural and energy policies in conjunction with advances in biotechnology converged to create an economic and regulatory environment that incentivized corn acreage expansion. Advancements in Bt seed and ethanol production technologies contributed to scale efficiency gains in corn and biofuel production. These advancements were accompanied by changes in market forces that altered the balance between corn and other agricultural crop production. The causal linkages among Bt adoption, ethanol production, and corn production are explored along with a discussion of how this shift toward corn production generated unexpected economic and environmental consequences. Alternative policy solutions to mitigate the negative consequences and enhance the resiliency of U.S. agriculture are discussed

Quantitative proteomics study of larval settlement in the barnacle Balanus amphitrite

KAUST Repository

Chen, Zhang-Fan; Zhang, Huoming; Wang, Hao; Matsumura, Kiyotaka; Wong, Yue Him; Ravasi, Timothy; Qian, Pei-Yuan

2014-01-01

Barnacles are major sessile components of the intertidal areas worldwide, and also one of the most dominant fouling organisms in fouling communities. Larval settlement has a crucial ecological effect not only on the distribution of the barnacle population but also intertidal community structures. However, the molecular mechanisms involved in the transition process from the larval to the juvenile stage remain largely unclear. In this study, we carried out comparative proteomic profiles of stage II nauplii, stage VI nauplii, cyprids, and juveniles of the barnacle Balanus amphitrite using label-free quantitative proteomics, followed by the measurement of the gene expression levels of candidate proteins. More than 700 proteins were identified at each stage; 80 were significantly up-regulated in cyprids and 95 in juveniles vs other stages. Specifically, proteins involved in energy and metabolism, the nervous system and signal transduction were significantly up-regulated in cyprids, whereas proteins involved in cytoskeletal remodeling, transcription and translation, cell proliferation and differentiation, and biomineralization were up-regulated in juveniles, consistent with changes associated with larval metamorphosis and tissue remodeling in juveniles. These findings provided molecular evidence for the morphological, physiological and biological changes that occur during the transition process from the larval to the juvenile stages in B. amphitrite. © 2014 Chen et al.

Quantitative proteomics study of larval settlement in the barnacle Balanus amphitrite

KAUST Repository

Chen, Zhang-Fan

2014-02-13

Barnacles are major sessile components of the intertidal areas worldwide, and also one of the most dominant fouling organisms in fouling communities. Larval settlement has a crucial ecological effect not only on the distribution of the barnacle population but also intertidal community structures. However, the molecular mechanisms involved in the transition process from the larval to the juvenile stage remain largely unclear. In this study, we carried out comparative proteomic profiles of stage II nauplii, stage VI nauplii, cyprids, and juveniles of the barnacle Balanus amphitrite using label-free quantitative proteomics, followed by the measurement of the gene expression levels of candidate proteins. More than 700 proteins were identified at each stage; 80 were significantly up-regulated in cyprids and 95 in juveniles vs other stages. Specifically, proteins involved in energy and metabolism, the nervous system and signal transduction were significantly up-regulated in cyprids, whereas proteins involved in cytoskeletal remodeling, transcription and translation, cell proliferation and differentiation, and biomineralization were up-regulated in juveniles, consistent with changes associated with larval metamorphosis and tissue remodeling in juveniles. These findings provided molecular evidence for the morphological, physiological and biological changes that occur during the transition process from the larval to the juvenile stages in B. amphitrite. © 2014 Chen et al.

Microbial gut diversity of Africanized and European honey bee larval instars.

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Svjetlana Vojvodic

Full Text Available The first step in understanding gut microbial ecology is determining the presence and potential niche breadth of associated microbes. While the core gut bacteria of adult honey bees is becoming increasingly apparent, there is very little and inconsistent information concerning symbiotic bacterial communities in honey bee larvae. The larval gut is the target of highly pathogenic bacteria and fungi, highlighting the need to understand interactions between typical larval gut flora, nutrition and disease progression. Here we show that the larval gut is colonized by a handful of bacterial groups previously described from guts of adult honey bees or other pollinators. First and second larval instars contained almost exclusively Alpha 2.2, a core Acetobacteraceae, while later instars were dominated by one of two very different Lactobacillus spp., depending on the sampled site. Royal jelly inhibition assays revealed that of seven bacteria occurring in larvae, only one Neisseriaceae and one Lactobacillus sp. were inhibited. We found both core and environmentally vectored bacteria with putatively beneficial functions. Our results suggest that early inoculation by Acetobacteraceae may be important for microbial succession in larvae. This assay is a starting point for more sophisticated in vitro models of nutrition and disease resistance in honey bee larvae.

Automated mapping of soybean and corn using phenology

Science.gov (United States)

Zhong, Liheng; Hu, Lina; Yu, Le; Gong, Peng; Biging, Gregory S.

2016-09-01

For the two of the most important agricultural commodities, soybean and corn, remote sensing plays a substantial role in delivering timely information on the crop area for economic, environmental and policy studies. Traditional long-term mapping of soybean and corn is challenging as a result of the high cost of repeated training data collection, the inconsistency in image process and interpretation, and the difficulty of handling the inter-annual variability of weather and crop progress. In this study, we developed an automated approach to map soybean and corn in the state of Paraná, Brazil for crop years 2010-2015. The core of the approach is a decision tree classifier with rules manually built based on expert interaction for repeated use. The automated approach is advantageous for its capacity of multi-year mapping without the need to re-train or re-calibrate the classifier. Time series MODerate-resolution Imaging Spectroradiometer (MODIS) reflectance product (MCD43A4) were employed to derive vegetation phenology to identify soybean and corn based on crop calendar. To deal with the phenological similarity between soybean and corn, the surface reflectance of the shortwave infrared band scaled to a phenological stage was used to fully separate the two crops. Results suggested that the mapped areas of soybean and corn agreed with official statistics at the municipal level. The resultant map in the crop year 2012 was evaluated using an independent reference data set, and the overall accuracy and Kappa coefficient were 87.2% and 0.804 respectively. As a result of mixed pixel effect at the 500 m resolution, classification results were biased depending on topography. In the flat, broad and highly-cropped areas, uncultivated lands were likely to be identified as soybean or corn, causing over-estimation of cropland area. By contrast, scattered crop fields in mountainous regions with dense natural vegetation tend to be overlooked. For future mapping efforts, it has great

Thermal Decomposition Properties of Materials from Different Parts of Corn Stalk

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Siwei Huang

2015-02-01

Full Text Available To help better utilize corn stalk (CS, pyrolysis behavior of materials from different parts of the CS including corn stalk without pith, corn root, and corn leaf were analyzed using thermogravimetric analysis (TGA at heating rates of 5, 10, 20, and 25 °C/min. The apparent activation energies determined by the Friedman method for corn stalk without pith, corn root, and corn leaf were in the range of 26.4 to 103.6 kJ/mol, 37.6 to 69.5 kJ/mol, and 35.0 to 103.9 kJ/mol, respectively, depending on the conversion. The main thermal decomposition occurred within a temperature range of 200 to 350 °C (±10 °C. Most of the volatile materials decomposed at less than a 0.8 conversion rate. At greater than a 0.8 conversion rate, the remaining material was mainly char, and the decomposition of char proceeded at higher conversion rates. Different pyrolysis characteristics in the CS indicated that different treatments should be chosen according to different parts for achieving the optimum conversion rate in practical applications.

Evaluating fuel ethanol feedstocks from energy policy perspectives: A comparative energy assessment of corn and corn stover

International Nuclear Information System (INIS)

Lavigne, Amanda; Powers, Susan E.

2007-01-01

Concerns surrounding the continued, un-checked use of petroleum-based fuels in the transportation sector, the search for more sustainable, renewable alternatives, and the constraints of the existing supply infrastructure in the United States have placed a spotlight on biomass-derived fuels. The central question of the ethanol debate has changed from 'Should we make ethanol?' to 'From what should we make ethanol?' emphasizing the importance of understanding the differences between specific biomass supply systems for fuel ethanol. When presented with numerous options, the priorities of an individual decision maker will define which feedstock alternative is the most appropriate choice for development from their perspective. This paper demonstrates how energy data can be successfully used to quantify assessment metrics beyond a standard net energy value calculation, thus quantifying the relative 'value' of ethanol supply systems. This value is defined based on decision-maker priorities that were adopted from national energy policy priorities: increased national energy security and increased conservation of energy resources. Nine energy assessment metrics that quantify detailed system energy data are calculated and a straightforward comparative assessment is performed between corn and corn stover feedstocks produced under the same farm scenario. Corn stover is shown to be more compatible with the national energy policy priorities and it is recommended that additional research be performed on utilizing this feedstock from the corn farm

75 FR 27772 - Corning Natural Gas Corporation; Notice of Compliance Filing

Science.gov (United States)

2010-05-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR09-30-002] Corning Natural Gas Corporation; Notice of Compliance Filing May 11, 2010. Take notice that on May 3, 2010, Corning Natural Gas Corporation, (Corning) filed its Statement of section 311 Operating Conditions in compliance...

Aerial spray deposition on corn silks applied at high and low spray rates

Science.gov (United States)

Corn earworm is a major pest of sweet corn, especially when grown organically. Aerial application of insecticides is important for both conventionally- and organically-grown sweet corn production as sweet corn is frequently irrigated to assure return on investment given the high production costs. ...

Larval connectivity of pearl oyster through biophysical modelling; evidence of food limitation and broodstock effect

Science.gov (United States)

Thomas, Yoann; Dumas, Franck; Andréfouët, Serge

2016-12-01

The black-lip pearl oyster (Pinctada margaritifera) is cultured extensively to produce black pearls, especially in French Polynesia atoll lagoons. This aquaculture relies on spat collection, a process that experiences spatial and temporal variability and needs to be optimized by understanding which factors influence recruitment. Here, we investigate the sensitivity of P. margaritifera larval dispersal to both physical and biological factors in the lagoon of Ahe atoll. Coupling a validated 3D larval dispersal model, a bioenergetics larval growth model following the Dynamic Energy Budget (DEB) theory, and a population dynamics model, the variability of lagoon-scale connectivity patterns and recruitment potential is investigated. The relative contribution of reared and wild broodstock to the lagoon-scale recruitment potential is also investigated. Sensitivity analyses pointed out the major effect of the broodstock population structure as well as the sensitivity to larval mortality rate and inter-individual growth variability to larval supply and to the subsequent settlement potential. The application of the growth model clarifies how trophic conditions determine the larval supply and connectivity patterns. These results provide new cues to understand the dynamics of bottom-dwelling populations in atoll lagoons, their recruitment, and discuss how to take advantage of these findings and numerical models for pearl oyster management.

Multi-state trials of Bt sweet corn varieties for control of the corn earworm (Lepidoptera: Noctuidae).

Science.gov (United States)

Shelton, A M; Olmstead, D L; Burkness, E C; Hutchison, W D; Dively, G; Welty, C; Sparks, A N

2013-10-01

Field tests in 2010-2011 were performed in New York, Minnesota, Maryland, Ohio, and Georgia to compare Bt sweet corn lines expressing Cry1A.105 + Cry2Ab2 and Cry1Ab with their non-Bt isolines, with and without the use of foliar insecticides. The primary insect pest in all locations during the trial years was Heliocoverpa zea (Boddie), which is becoming the most serious insect pest of sweet corn in the United States. At harvest, the ears were measured for marketability according to fresh market and processing standards. For fresh market and processing, least squares regression showed significant effects of protein expression, state, and insecticide frequency. There was a significant effect of year for fresh market but not for processing. The model also showed significant effects of H. zea per ear by protein expression. Sweet corn containing two genes (Cry1A.105 + Cry2Ab2) and a single gene (Cry1Ab) provided high marketability, and both Bt varieties significantly outperformed the traditional non-Bt isolines in nearly all cases regardless of insecticide application frequency. For pest suppression of H. zea, plants expressing Bt proteins consistently performed better than non-Bt isoline plants, even those sprayed at conventional insecticide frequencies. Where comparisons in the same state were made between Cry1A.105 + Cry2Ab2 and Cry1Ab plants for fresh market, the product expressing Cry1A.105 + Cry2Ab2 provided better protection and resulted in less variability in control. Overall, these results indicate Cry1A.105 + Cry2Ab2 and Cry1Ab plants are suitable for fresh market and processing corn production across a diversity of growing regions and years. Our results demonstrate that Bt sweet corn has the potential to significantly reduce the use of conventional insecticides against lepidopteran pests and, in turn, reduce occupational and environmental risks that arise from intensive insecticide use.

Larval biology of the crab Rhithropanopeus harrisii (Gould): a synthesis.

Science.gov (United States)

Forward, Richard B

2009-06-01

This synthesis reviews the physiological ecology and behavior of larvae of the benthic crab Rhithropanopeus harrisii, which occurs in low-salinity areas of estuaries. Larvae are released rhythmically around the time of high tide in tidal estuaries and in the 2-h interval after sunset in nontidal estuaries. As in most subtidal crustaceans, the timing of larval release is controlled by the developing embryos, which release peptide pheromones that stimulate larval release behavior by the female to synchronize the time of egg hatching. Larvae pass through four zoeal stages and a postlarval or megalopal stage that are planktonic before metamorphosis. They are retained near the adult population by means of an endogenous tidal rhythm in vertical migration. Larvae have several safeguards against predation: they undergo nocturnal diel vertical migration (DVM) and have a shadow response to avoid encountering predators, and they bear long spines as a deterrent. Photoresponses during DVM and the shadow response are enhanced by exposure to chemical cues from the mucus of predator fishes and ctenophores. The primary visual pigment has a spectral sensitivity maximum at about 500 nm, which is typical for zooplankton and matches the ambient spectrum at twilight. Larvae can detect vertical gradients in temperature, salinity, and hydrostatic pressure, which are used for depth regulation and avoidance of adverse environmental conditions. Characteristics that are related to the larval habitat and are common to other crab larval species are considered.

Bioaugmentation for Electricity Generation from Corn Stover Biomass Using Microbial Fuel Cells

KAUST Repository

Wang, Xin

2009-08-01

Corn stover is usually treated by an energy-intensive or expensive process to extract sugars for bioenergy production. However, it is possible to directly generate electricity from corn stover in microbial fuel cells (MFCs) through the addition of microbial consortia specifically acclimated for biomass breakdown. A mixed culture that was developed to have a high saccharification rate with corn stover was added to singlechamber, air-cathode MFCs acclimated for power production using glucose. The MFC produced a maximum power of 331 mW/ m 2 with the bioaugmented mixed culture and corn stover, compared to 510 mW/m2 using glucose. Denaturing gradient gel electrophoresis (DGGE) showed the communities continued to evolve on both the anode and corn stover biomass over 60 days, with several bacteria identified including Rhodopseudomonas palustris. The use of residual solids from the steam exploded corn stover produced 8% more power (406 mW/m2) than the raw corn stover. These results show that it is possible to directly generate electricity from waste corn stover in MFCs through bioaugmentation using naturally occurring bacteria. © 2009 American Chemical Society.

Quantitative analysis of allantoin in Iranian corn silk

Directory of Open Access Journals (Sweden)

E. Khanpour*

2017-11-01

Full Text Available Background and objectives: Zea mays is cultivated in different parts of Iran and corn silk is used in traditional medicine. Allantoin is one of the major compounds in corn silk. The purpose of this research was the quantitatve analysis of allantoin in corn silks belonging to several regions of Iran. Methods: The samples of corn silk were prepared from three provinces of Iran (Kermanshah, Fars and Razavi Khorasan. The dried plant materials were infused in boiling distilled water with a temperature of 90-95 °C on magnetic stirrer for 30 min. The levels of allantoin in aqueous extracts were determined by HPLC. Quantification was achieved using an C18 column (250×4.6 mm, 5 µm under isocratic conditions and phosphate buffer solution (pH 3.0 as the mobile phase at a flow rate of 0.5 mL/min. Column effluent was monitored at 210 nm. The calibration curve of allantoin standard was plotted with concentrations from 6.25 to 100 µg/mL. Results: The calibration curve of standard was linear over the concentration range used (R2=0.9999. The results showed that the amount of allantoin in samples was between 205 and 374 mg/100g of dry plant material. The corn silk samples of Razavi Khorasan and Fars provinces showed the lowest and highest amount of allantoin, respectively. Conclusion: The levels of allantoin obtained in this study were higher than the values reported in other studies; therefore, the researchers of this project are investigating the wound healing effect of corn silk.

Modeling evolution of resistance of sugarcane borer (Lepidoptera: Crambidae) to transgenic Bt corn.

Science.gov (United States)

Kang, J; Huang, F; Onstad, D W

2014-08-01

Diatraea saccharalis (F.) (Lepidoptera: Crambidae) is a target pest of transgenic corn expressing Bacillus thuringiensis (Bt) protein, and the first evidence of resistance by D. saccharalis to Cry1Ab corn was detected in a field population in northeast Louisiana in 2004. We used a model of population dynamics and genetics of D. saccharalis to 1) study the effect of interfield dispersal, the first date that larvae enter diapause for overwintering, toxin mortality, the proportion of non-Bt corn in the corn patch, and the area of a crop patch on Bt resistance evolution; and 2) to identify gaps in empirical knowledge for managing D. saccharalis resistance to Bt corn. Increasing, the proportion of corn refuge did not always improve the durability of Bt corn if the landscape also contained sugarcane, sorghum, or rice. In the landscape, which consisted of 90% corn area, 5% sorghum area, and 5% rice area, the durability of single-protein Bt corn was 40 yr when the proportion of corn refuge was 0.2 but 16 yr when the proportion of corn refuge was 0.5. The Bt resistance evolution was sensitive to a change (from Julian date 260 to 272) in the first date larvae enter diapause for overwintering and moth movement. In the landscapes with Bt corn, non-Bt corn, sugarcane, sorghum, and rice, the evolution of Bt resistance accelerated when larvae entered diapause for overwintering early. Intermediate rates of moth movement delayed evolution of resistance more than either extremely low or high rates. This study suggested that heterogeneity in the agrolandscapes may complicate the strategy for managing Bt resistance in D. saccharalis, and designing a Bt resistance management strategy for D. saccharalis is challenging because of a lack of empirical data about overwintering and moth movement.

In growing pigs, the true ileal and total tract digestibility of acid hydrolyzed ether extract in extracted corn oil is greater than in intact sources of corn oil or soybean oil.

Science.gov (United States)

Kim, B G; Kil, D Y; Stein, H H

2013-02-01

An experiment was conducted to determine the true ileal digestibility (TID) and the true total tract digestibility (TTTD) of acid-hydrolyzed ether extract (AEE) in extracted corn oil, high-oil corn, distillers dried grains with solubles (DDGS), corn germ, and high protein distillers dried grains (HP DDG) and to compare these values to the TID and TTTD of AEE in full-fat soybeans. Nineteen barrows with an initial BW of 52.2 kg (SD = 3.8) were fitted with a T-cannula in the distal ileum and allotted to a 19 × 11 Youden square design with 19 diets and 11 periods. A basal diet based on cornstarch, casein, sucrose, and corn bran was formulated. Eighteen additional diets were formulated by adding 3 levels of extracted corn oil, high-oil corn, DDGS, corn germ, HP DDG, or full-fat soybeans to the basal diet. The apparent ileal and the apparent total tract digestibility of AEE were calculated for each diet. The endogenous flow of AEE associated with each ingredient and values for TID and TTTD were calculated using the regression procedure. Results indicated that digested AEE in ileal digesta and feces linearly increased as AEE intake increased regardless of ingredient (P 0.77). However, the ileal and fecal endogenous losses of AEE were different (P oil, HP DDG, and full-fat soybeans. The TID of AEE was greater (P oil (95.4%) than for all other ingredients. The TID of AEE in HP DDG (76.5%) was not different from the TID of AEE in full-fat soybeans (85.2%) but greater (P oil corn, DDGS, and corn germ (53.0, 62.1, and 50.1%, respectively). The TTTD of AEE was greater (P oil (94.3%) than for all other ingredients, and the TTTD in full-fat soybeans (79.7%) was greater (P oil corn, DDGS, corn germ, and HP DDG (41.4, 51.9, 43.9, and 70.2%, respectively). The TTTD of AEE in HP DDG was also greater (P oil corn, DDGS, and corn germ. In conclusion, the intact sources of oil originating from high-oil corn, DDGS, corn germ, or HP DDG are much less digestible than extracted corn oil

Toxicity of organophosphorus pesticide sumithion on larval stages of stinging catfish Heteropneustes fossilis

NARCIS (Netherlands)

Shahjahan, M.; Kabir, M.F.; Sumon, Kizar Ahmed; Bhowmik, Lipi Rani; Rashid, Harunur

2017-01-01

Sumithion is widely used to control brittle in paddy fields and tiger bug in fish larval rearing ponds. The objective of this study was to elucidate the toxic effects of sumithion on larval stages of stinging catfish Heteropneustes fossilis. Larvae were exposed to two concentrations (150 and 250

75 FR 28602 - Corning Natural Gas Corporation; Notice of Compliance Filing

Science.gov (United States)

2010-05-21

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR09-30-003] Corning Natural Gas Corporation; Notice of Compliance Filing May 17, 2010. Take notice that on May 10, 2010, Corning Natural Gas Corporation, (Corning) filed a corrected rate sheet to replace the rate sheet filed with its...

Hydrocolloid occlusion for the treatment of neurovascular corns

DEFF Research Database (Denmark)

Petersen, Lars Jelstrup; Beck, Jan Walther; Reumert, L N

1991-01-01

The goal of this study was to determine the effect of hydrocolloid occlusion on neurovascular corns. The design was an observer-blinded, randomized, controlled study. Thirty consecutive patients participated in the trial. The patients received curettage alone or curettage with hydrocolloid...... occlusion. Six treatments were given over 12 weeks. A follow-up examination was performed 3 months after termination of the trial. Outcome measures were the size of the corns, a discomfort score, and an overall judgment of the trial. The results demonstrated no benefit of occlusion for symptoms or signs...... of neurovascular corns. The patients treated with occlusion were, however, generally more satisfied than the conventional group....

Identification of corn fields using multidate radar data

International Nuclear Information System (INIS)

Shanmugan, K.S.; Ulaby, F.T.; Narayanan, V.; Dobson, C.

1983-01-01

Airborne C- and L-band radar data acquired over a test site in western Kansas were analyzed to determine corn-field identification accuracies obtainable using single-channel, multichannel, and multidate radar data. An automated pattern-recognition procedure was used to classify 144 fields into three categories: corn, pasture land, and bare soil (including wheat stubble and fallow). Corn fields were identified with accuracies ranging from 85% for single channel, single-date data to 100% for single-channel, multidate data. The effects of radar parameters such as frequency, polarization, and look angle as well as the effects of soil moisture on the classification accuracy are also presented

Beneficial Effects of Corn Silk on Metabolic Syndrome.

Science.gov (United States)

Wang, Bing; Xiao, Tiegang; Ruan, Jun; Liu, Wensheng

2017-01-01

Metabolic syndrome (MS) is a very common medical problem worldwide. It includes obesity, hypertension, hyperglycemia, and abnormal levels of triglycerides and high-density lipoprotein cholesterol. It is closely associated with insulin resistance and may lead to diabetes mellitus, liver diseases, or cardiovascular diseases. Corn silk (CS), a traditional Chinese medicine, has been reported to have multiple beneficial effects, including hypotensive, anti-diabetic, and hypolipidemic properties. This suggests that corn silk could be used to treat or prevent metabolic syndrome. In this review, we will discuss the potential role of corn silk in different components of metabolic syndrome. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

Science.gov (United States)

Farrell, E. R.; Fernandes, J.; Keshishian, H.

1996-01-01

In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

The neural basis of visual behaviors in the larval zebrafish.

Science.gov (United States)

Portugues, Ruben; Engert, Florian

2009-12-01

We review visually guided behaviors in larval zebrafish and summarise what is known about the neural processing that results in these behaviors, paying particular attention to the progress made in the last 2 years. Using the examples of the optokinetic reflex, the optomotor response, prey tracking and the visual startle response, we illustrate how the larval zebrafish presents us with a very promising model vertebrate system that allows neurocientists to integrate functional and behavioral studies and from which we can expect illuminating insights in the near future. Copyright 2009 Elsevier Ltd. All rights reserved.

Corn Cultivation to Reduce the Mycotoxin Contamination

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Yangseon Kim

2017-09-01

Full Text Available The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L. seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.

The induction of proteinases in corn and soybean by anoxia

International Nuclear Information System (INIS)

VanToai, T.; Hwang, Shihying

1989-01-01

This study characterized the anaerobic changes in proteinase activities in corn and soybean roots and to investigate the possibility that these changes might contribute to the differential anaerobiosis tolerance of the two species. After 24 h of anoxia, crude protein extracts from H60 corn and Keller soybean root tips (10cm) were assayed for proteinase activities at pH range from 4.5 to 9.5. Turnover of aberrant proteins was studied in seedlings labelled with 3 H-leucine for 12 h under: (a) puromycin (0.64 mM) in air, (b) ethanol (1%) in air, (c) nitrogen and (d) air. After the treatment, the labelled proteins remaining in roots were determined every 2 h for 6 h. In both corn and soybean, activities of alkali proteinases increased, and activities of acid proteinases declined under anoxia. Neutral proteinases increase in anoxic corn roots, but decline in anoxic soybean roots. The protein turnover rate in corn treated with puromycin, ethanol and nitrogen was much higher than in control roots. The protein turnover rate in soybean roots treated with puromycin, ethanol was similar to the rate of the control. The results indicated that: (a) anoxic corn can degrade aberrant proteins, but anoxic soybean cannot, (b) the degradation of aberrant proteins in anoxic corn is accomplished by neutral proteinases, and (c) the accumulation of aberrant proteins in soybean might contribute to the susceptibility of this species to anoxia

Interactive effects of maternal and environmental exposure to coal combustion wastes decrease survival of larval southern toads (Bufo terrestris)

International Nuclear Information System (INIS)

Metts, Brian S.; Buhlmann, Kurt A.; Scott, David E.; Tuberville, Tracey D.; Hopkins, William A.

2012-01-01

We conducted a mesocosm study to assess the individual and interactive effects of previous maternal exposure and larval exposure to trace element-laden sediments on southern toads (Bufo terrestris). Previous maternal exposure to coal combustion wastes (CCW) reduced larval survival to metamorphosis up to 57% compared to larvae of unexposed females. Larvae reared on CCW accumulated significant concentrations of trace elements resulting in extended larval periods, reduced growth rates, and reduced mass at metamorphosis. However, the effects were dependent on age of sediments, suggesting the effects of contaminants from CCW may be partially ameliorated over time through the reduced bioavailability of trace elements in aged CCW. Most importantly, maternal exposure to contaminants coupled with larval exposure to fresh CCW interacted to reduce survival to metamorphosis by 85% compared to reference conditions. Our study yields further evidence that disposal of CCW in aquatic basins potentially creates ecological traps for some amphibian populations. - Highlights: ► The interaction of maternal exposure and larval exposure to CCW reduced survival. ► Previous maternal exposure to CCW had a latent effect on survival to metamorphosis. ► Larval southern toads exposed to CCW experienced prolonged larval periods. ► Larval southern toads exposed to CCW had reduced growth rates. ► Larval southern toads exposed to CCW had reduced mass at metamorphosis. - Maternal and environmental exposure to coal combustion wastes interact to decrease survival in larval amphibians.

Viscoelastic properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover

Science.gov (United States)

The rheological properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover were investigated. The corn stover MFC gels exhibited concentration-dependent viscoelastic properties. Higher corn stover MFC concentrations resulted in stronger viscoelastic properties. Th...

Greenhouse gases in the corn-to-fuel ethanol pathway.

Energy Technology Data Exchange (ETDEWEB)

Wang, M. Q.

1998-06-18

Argonne National Laboratory (ANL) has applied its Greenhouse gas, Regulated Emissions and Energy in Transportation (GREET) full-fuel-cycle analysis model to examine greenhouse gas (GHG) emissions of corn-feedstock ethanol, given present and near-future production technology and practice. On the basis of updated information appropriate to corn farming and processing operations in the four principal corn- and ethanol-producing states (Illinois, Iowa, Minnesota, and Nebraska), the model was used to estimate energy requirements and GHG emissions of corn farming; the manufacture, transportation to farms, and field application of fertilizer and pesticide; transportation of harvested corn to ethanol plants; nitrous oxide emissions from cultivated cornfields; ethanol production in current average and future technology wet and dry mills; and operation of cars and light trucks using ethanol fuels. For all cases examined on the basis of mass emissions per travel mile, the corn-to-ethanol fuel cycle for Midwest-produced ethanol used in both E85 and E10 blends with gasoline outperforms conventional (current) and reformulated (future) gasoline with respect to energy use and GHG production. Also, GHG reductions (but not energy use) appear surprisingly sensitive to the value chosen for combined soil and leached N-fertilizer conversion to nitrous oxide. Co-product energy-use attribution remains the single key factor in estimating ethanol's relative benefits because this value can range from 0 to 50%, depending on the attribution method chosen.

Greenhouse gases in the corn-to-fuel ethanol pathway

International Nuclear Information System (INIS)

Wang, M. Q.

1998-01-01

Argonne National Laboratory (ANL) has applied its Greenhouse gas, Regulated Emissions and Energy in Transportation (GREET) full-fuel-cycle analysis model to examine greenhouse gas (GHG) emissions of corn-feedstock ethanol, given present and near-future production technology and practice. On the basis of updated information appropriate to corn farming and processing operations in the four principal corn- and ethanol-producing states (Illinois, Iowa, Minnesota, and Nebraska), the model was used to estimate energy requirements and GHG emissions of corn farming; the manufacture, transportation to farms, and field application of fertilizer and pesticide; transportation of harvested corn to ethanol plants; nitrous oxide emissions from cultivated cornfields; ethanol production in current average and future technology wet and dry mills; and operation of cars and light trucks using ethanol fuels. For all cases examined on the basis of mass emissions per travel mile, the corn-to-ethanol fuel cycle for Midwest-produced ethanol used in both E85 and E10 blends with gasoline outperforms conventional (current) and reformulated (future) gasoline with respect to energy use and GHG production. Also, GHG reductions (but not energy use) appear surprisingly sensitive to the value chosen for combined soil and leached N-fertilizer conversion to nitrous oxide. Co-product energy-use attribution remains the single key factor in estimating ethanol's relative benefits because this value can range from 0 to 50%, depending on the attribution method chosen

Microbial inoculant effects on silage and in vitro ruminal fermentation, and microbial biomass estimation for alfalfa, bmr corn, and corn silages

Science.gov (United States)

Third cut alfalfa, brown mid-rib (bmr) corn, and corn were chopped and inoculated with one of four different strains of lactic acid bacteria (LAB). Uninoculated silage was the control treatment. For each crop, four mini-silos 1-L glass jars were ensiled per treatment. All silos were fermented for 60...

21 CFR 184.1866 - High fructose corn syrup.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true High fructose corn syrup. 184.1866 Section 184.1866... Listing of Specific Substances Affirmed as GRAS § 184.1866 High fructose corn syrup. (a) High fructose... partial enzymatic conversion of glucose (dextrose) to fructose using an insoluble glucose isomerase enzyme...

Climate change impacts on corn phenology and productivity

Science.gov (United States)

Climate is changing around the world and will impact future production of all food and feed crops. Corn is no exception to these impacts and to ensure a future supply of this vital crop we must begin to understand how climate impacts both the phenological development of corn and the productivity. Te...

An automated approach to mapping corn from Landsat imagery

Science.gov (United States)

Maxwell, S.K.; Nuckols, J.R.; Ward, M.H.; Hoffer, R.M.

2004-01-01

Most land cover maps generated from Landsat imagery involve classification of a wide variety of land cover types, whereas some studies may only need spatial information on a single cover type. For example, we required a map of corn in order to estimate exposure to agricultural chemicals for an environmental epidemiology study. Traditional classification techniques, which require the collection and processing of costly ground reference data, were not feasible for our application because of the large number of images to be analyzed. We present a new method that has the potential to automate the classification of corn from Landsat satellite imagery, resulting in a more timely product for applications covering large geographical regions. Our approach uses readily available agricultural areal estimates to enable automation of the classification process resulting in a map identifying land cover as ‘highly likely corn,’ ‘likely corn’ or ‘unlikely corn.’ To demonstrate the feasibility of this approach, we produced a map consisting of the three corn likelihood classes using a Landsat image in south central Nebraska. Overall classification accuracy of the map was 92.2% when compared to ground reference data.

Physicochemical, Thermal, and Sensory Properties of Blue Corn (Zea Mays L.).

Science.gov (United States)

Mutlu, Ceren; Arslan-Tontul, Sultan; Candal, Cihadiye; Kilic, Ozlem; Erbas, Mustafa

2018-01-01

The aim of this study was to investigate some physicochemical and sensory properties of blue corn cultivated in Turkey. The length and width of the cob with kernels, hectoliter, and 1000-kernel weight of blue corn were measured as 7.66, 2.02 mm, 84.40 kg/100 L, and 44.27 g, respectively. The gelatinization onset, peak, and end temperatures were measured as 61.12 °C, 64.35 °C, and 75.65 °C, respectively. The water activity, moisture content, total protein, lipid, and crude fiber contents of the blue corn sample were detected as 0.44, 9.39%, 13.13%, 4.30%, and 2.68%, respectively. Total starch and resistant starch contents of blue corn were determined as 63.94% and 8.89%, respectively. Also, total monomeric anthocyanin content and antioxidant capacity of blue corn were detected as 915.43 mg CGE/kg and 7.99 μmol TE/g, respectively. Additionally, the major fatty acids detected in blue corn samples were palmitic, stearic, oleic, and linoleic acids. Blue corn can be utilized in the production of enjoyable and healthier snacks, such as popcorn and chips, because of its color and high phenolic, anthocyanin, and fiber contents. © 2017 Institute of Food Technologists®.

Ovarian development and early larval survival of Stenopus zanzibaricus (Bruce, 1976

Directory of Open Access Journals (Sweden)

Daniel Marques

2014-06-01

Full Text Available Despite economically valuable, ornamental shrimps are poorly studied and there is a lack of protocols for their captive breeding. Stenopus is one of the most important genera of ornamental shrimps, being Stenopus zanzibaricus one of the species with less information about captive breeding and larviculture. For a better knowledge of its reproductive cycle, we evaluated morphological and color changes during ovarian development of adult females through daily photographs taken during all the cycle. The effect of three diets (Brachionus plicatilis + Tetraselmis chuii; newly artemia nauplii + Tetraselmis chuii; newly artemia nauplii and two different temperatures (25ºC and 27ºC on early larval development were also evaluated. With this study, it was expected to obtain some insight about Stenopus zanzibaricus reproductive cycle and early larval development, in order to develop captive breeding and larval rearing protocols for this economic valuable species.

EFFECTS OF FIVE NEW COMPOUNDS ON THE LARVAL GROWTH AND DIGESTIVE PHYSIOLOGY OF THE ASIATIC CORN BORER, OSTRINIA FURNA CALIS LARVAE

Institute of Scientific and Technical Information of China (English)

JiaHe; Zeng-guangYan; Zhi-shengJiang

2003-01-01

Five new compounds were tested on the growth and antifeeding activity compared with toosendanin against fifth instar larvae Ostrinia furtuwalis. The activities of two proteases, a weak alkaline trypsine-like enzyme and a chymotrypsin-like enzyme, in the midgut of Ostriniafurnacalis larvae were also measured. Experimental restilts suggest that when incorporated into an artificial diet at the concentration of 500mg/kg, the antifeeding activities of toosendanin, C19 , C23 , C24 , C26 , C28 were 51.16%, 57.61%, 4.28%, 51.08%, 36.73% and 51.67%,respectively, C19, C24, C28 had no significant difference with toosendanin. At 20mg/kg, the larval growth were remarkably suppressed by CI9, C26, C28, the inhibition of C28 was close to toosendanin in 48 h. The two proteases were activated by toosendanin and C28 while they were inhibited in 48 h but activated in 24 h by C19, C24 and C26,In this paper, the related functions and mechanisms were discussed.

Live Cell Imaging of Butterfly Pupal and Larval Wings In Vivo.

Directory of Open Access Journals (Sweden)

Yoshikazu Ohno

Full Text Available Butterfly wing color patterns are determined during the late larval and early pupal stages. Characterization of wing epithelial cells at these stages is thus critical to understand how wing structures, including color patterns, are determined. Previously, we successfully recorded real-time in vivo images of developing butterfly wings over time at the tissue level. In this study, we employed similar in vivo fluorescent imaging techniques to visualize developing wing epithelial cells in the late larval and early pupal stages 1 hour post-pupation. Both larval and pupal epithelial cells were rich in mitochondria and intracellular networks of endoplasmic reticulum, suggesting high metabolic activities, likely in preparation for cellular division, polyploidization, and differentiation. Larval epithelial cells in the wing imaginal disk were relatively large horizontally and tightly packed, whereas pupal epithelial cells were smaller and relatively loosely packed. Furthermore, larval cells were flat, whereas pupal cells were vertically elongated as deep as 130 μm. In pupal cells, many endosome-like or autophagosome-like structures were present in the cellular periphery down to approximately 10 μm in depth, and extensive epidermal feet or filopodia-like processes were observed a few micrometers deep from the cellular surface. Cells were clustered or bundled from approximately 50 μm in depth to deeper levels. From 60 μm to 80 μm in depth, horizontal connections between these clusters were observed. The prospective eyespot and marginal focus areas were resistant to fluorescent dyes, likely because of their non-flat cone-like structures with a relatively thick cuticle. These in vivo images provide important information with which to understand processes of epithelial cell differentiation and color pattern determination in butterfly wings.

Grain yield of corn at different population densities and intercropped with forages

Directory of Open Access Journals (Sweden)

José M. do Nascimento

2015-12-01

Full Text Available ABSTRACT The no-tillage system optimizes agricultural areas, maintaining the supply of straw and promoting crop rotation and soil conservation. The aim of the present study was to evaluate sowing quality and grain yield of corn intercropped with three forage species of the Urochloa genus associated with two corn population densities. The experiment was conducted at the São Paulo State University (UNESP, in Jaboticabal-SP, Brazil. The experimental design was randomized blocks in a 2 x 3 factorial scheme with four replicates. The treatments consisted of two corn densities (55,000 and 75,000 plants ha-1 intercropped with three forages (Urochloa brizantha, Urochloa decumbens and Urochloa ruziziensis sown between rows of corn in the V4 stage. The following corn variables were analysed: mean number of days for emergence, longitudinal distribution, grain yield, initial population and final population. There were differences between corn populations (p < 0.1 and the intercropping of corn with the species U. brizantha and U. ruziziensis promoted the best results, which permitted concluding that the cultivation of corn at the population density of 75,000 plants ha-1 intercropped U. brizantha and U. ruziziensis promoted better sowing quality and, consequently, higher grain yields.

Toxicity of methylmercury injected into eggs when dissolved in water versus corn oil

Science.gov (United States)

Heinz, G.H.; Hoffman, D.J.; Klimstra, J.D.; Stebbins, K.R.; Kondrad, S.L.

2011-01-01

In a previous study, the embryotoxicity of methylmercury dissolved in corn oil was compared among 26 species of birds. Corn oil is not soluble in the water-based matrix that constitutes the albumen of an egg. To determine whether the use of corn oil limited the usefulness of this earlier study, a comparison was made of the embryotoxicity of methylmercury dissolved in corn oil versus water. Mallard (Anas platyrhynchos) and chicken (Gallus gallus) eggs were injected with methylmercury chloride dissolved in corn oil or water to achieve concentrations of 0, 0.2, 0.4, 0.8, and 1.6??g/g mercury in the egg on a wet weight basis. Hatching success at each dose of mercury was compared between the two solvents. For mallards, 16.4% of the eggs injected with 1.6??g/g mercury dissolved in water hatched, which was statistically lower than the 37.6% hatch rate of eggs injected with 1.6??g/g mercury dissolved in corn oil, but no differences in hatching success were observed between corn oil and water at any of the other doses. With chicken eggs, no significant differences occurred in percentage hatch of eggs between corn oil and water at any of the mercury doses. Methylmercury dissolved in corn oil seems to have a toxicity to avian embryos similar to that of does methylmercury dissolved in water. Consequently, the results from the earlier study that described the toxicity of methylmercury dissolved in corn oil to avian embryos were probably not compromised by the use of corn oil as a solvent. ?? 2011 SETAC.

Competitiveness of Brazilian sugarcane ethanol compared to US corn ethanol

International Nuclear Information System (INIS)

Crago, Christine L.; Khanna, Madhu; Barton, Jason; Giuliani, Eduardo; Amaral, Weber

2010-01-01

Corn ethanol produced in the US and sugarcane ethanol produced in Brazil are the world's leading sources of biofuel. Current US biofuel policies create both incentives and constraints for the import of ethanol from Brazil and together with the cost competitiveness and greenhouse gas intensity of sugarcane ethanol compared to corn ethanol will determine the extent of these imports. This study analyzes the supply-side determinants of cost competitiveness and compares the greenhouse gas intensity of corn ethanol and sugarcane ethanol delivered to US ports. We find that while the cost of sugarcane ethanol production in Brazil is lower than that of corn ethanol in the US, the inclusion of transportation costs for the former and co-product credits for the latter changes their relative competitiveness. We also find that the relative cost of ethanol in the US and Brazil is highly sensitive to the prevailing exchange rate and prices of feedstocks. At an exchange rate of US1=R2.15 the cost of corn ethanol is 15% lower than the delivered cost of sugarcane ethanol at a US port. Sugarcane ethanol has lower GHG emissions than corn ethanol but a price of over $113 per ton of CO 2 is needed to affect competitiveness. (author)

Complementation of sweet corn mutants: a method for grouping ...

Indian Academy of Sciences (India)

for sweet corn are now expanding and the demands are increasing due to ... tropical/tropical regions of India is amongst one of the factors ... Maize endosperm mutant genes that affect quality of sweet corn can ... Thus, the concept of comple-.

Phenology and biomass production of adapted and non-adapted tropical corn populations in Central Iowa

Science.gov (United States)

Biofuel production in the Midwestern United States has largely focused on corn (Zea mays L.) grain for ethanol production and more recently, corn stover for lignocellulosic ethanol. As an alternative to conventional corn, tropical corn populations have been evaluated. Tropical corn is the term used ...

Distribución temporal y espacial de poblaciones larvarias de Spodoptera frugiperda (Smith (Lep.: Noctuidae en diferentes hospederos en provincias del norte de la Argentina Spatial and temporal distribution of Spodoptera frugiperda (Smith (Lep.: Noctuidae larval populations on different host plants in northern Argentina provinces

Directory of Open Access Journals (Sweden)

M. Gabriela Murúa

Full Text Available Para estudiar la distribución temporal y espacial de larvas del "cogollero del maíz" Spodoptera frugiperda en diferentes plantas hospederas, se realizaron muestreos sistemáticos desde el año 2004 al 2007 en diferentes asociaciones de cultivos en las provincias de Tucumán, Salta y Santiago del Estero. Se consideró "asociación de cultivos" a una zona donde coexistían simultáneamente (en tiempo y espacio más de dos cultivos colindantes. Los cultivos monitoreados fueron maíz, sorgo granífero, alfalfa, caña de azúcar, soja, trigo, cártamo, garbanzo y malezas. En cada uno se muestrearon cinco puntos al azar de 1 m² y se revisaron las plantas, recolectándose las posturas y/o larvas presentes. Se encontraron 3620 larvas. La mayor cantidad se recolectó durante los meses del verano en las tres campañas monitoreadas en todas las provincias. Su presencia estuvo relacionada con la aparición de los cultivos estivales como el maíz y el sorgo granífero, en todas las provincias. La mayor cantidad de larvas se obtuvieron en maíz (2894, independientemente de los otros cultivos que formaban parte de la asociación. Siguiendo en orden de importancia, los otros hospederos con larvas fueron: sorgo granífero (272, alfalfa (125 y malezas (282. En base al número de larvas encontradas, la soja, trigo y caña de azúcar, cultivos que estuvieron presentes en casi todas las asociaciones, no son hospederos preferenciales de esta especie.In order to study the spatial and temporal distribution of fall armyworm Spodoptera frugiperda larval populations on different host plants, systematic samplings were made from 2004 to 2007 in different crop associations in the provinces of Tucumán, Salta and Santiago del Estero. A zone where more than two adjacent crops coexisted simultaneously (in time and space was considered a crop association. Sampled crops were corn, sorghum, alfalfa, sugarcane, soybean, wheat, safflower, chickpea and weeds. Five one

Physicochemical properties of different corn varieties by principal components analysis and cluster analysis

International Nuclear Information System (INIS)

Zeng, J.; Li, G.; Sun, J.

2013-01-01

Principal components analysis and cluster analysis were used to investigate the properties of different corn varieties. The chemical compositions and some properties of corn flour which processed by drying milling were determined. The results showed that the chemical compositions and physicochemical properties were significantly different among twenty six corn varieties. The quality of corn flour was concerned with five principal components from principal component analysis and the contribution rate of starch pasting properties was important, which could account for 48.90%. Twenty six corn varieties could be classified into four groups by cluster analysis. The consistency between principal components analysis and cluster analysis indicated that multivariate analyses were feasible in the study of corn variety properties. (author)

Impact of NAFTA on U.S. Corn Trade with Mexico

OpenAIRE

A. A. Farhad Chowdhury; Albert J. Allen

2005-01-01

The objective of this paper is to assess the impact of NAFTA vis-a-vis other domestic and environmental forces in corn trading between the U.S. and Mexico. Regression analysis could not provide conclusive evidence that the post-NAFTA increase in corn trade was solely due to NAFTA. Severe drought in Mexico and its domestic policy reforms may have contributed to the increased volume of corn trade in the post-NAFTA era.

Efficiency of two larval diets for mass-rearing of the mosquito Aedes aegypti.

Directory of Open Access Journals (Sweden)

J G Bond

Full Text Available Aedes aegypti is a major vector of arboviruses that may be controlled on an area-wide basis using the sterile insect technique (SIT. Larval diet is a major factor in mass-rearing for SIT programs. We compared dietary effects on immature development and adult fitness-related characteristics for an International Atomic Energy Agency (IAEA diet, developed for rearing Ae. albopictus, and a standardized laboratory rodent diet (LRD, under a 14:10 h (light:dark photoperiod ("light" treatment or continuous darkness during larval rearing. Larval development was generally fastest in the IAEA diet, likely reflecting the high protein and lipid content of this diet. The proportion of larvae that survived to pupation or to adult emergence did not differ significantly between diets or light treatments. Insects from the LRD-dark treatment produced the highest proportion of male pupae (93% at 24 h after the beginning of pupation whereas adult sex ratio from the IAEA diet tended to be more male-biased than that of the LRD diet. Adult longevity did not differ significantly with larval diet or light conditions, irrespective of sex. In other aspects the LRD diet generally performed best. Adult males from the LRD diet were significantly larger than those from the IAEA diet, irrespective of light treatment. Females from the LRD diet had ~25% higher fecundity and ~8% higher egg fertility compared to those from the IAEA diet. Adult flight ability did not differ between larval diets, and males had a similar number of copulations with wild females, irrespective of larval diet. The LRD diet had lower protein and fat content but a higher carbohydrate and energetic content than the IAEA diet. We conclude that the LRD diet is a low-cost standardized diet that is likely to be suitable for mass-rearing of Ae. aegypti for area-wide SIT-based vector control.

High speed measurement of corn seed viability using hyperspectral imaging

Science.gov (United States)

Ambrose, Ashabahebwa; Kandpal, Lalit Mohan; Kim, Moon S.; Lee, Wang-Hee; Cho, Byoung-Kwan

2016-03-01

Corn is one of the most cultivated crops all over world as food for humans as well as animals. Optimized agronomic practices and improved technological interventions during planting, harvesting and post-harvest handling are critical to improving the quantity and quality of corn production. Seed germination and vigor are the primary determinants of high yield notwithstanding any other factors that may play during the growth period. Seed viability may be lost during storage due to unfavorable conditions e.g. moisture content and temperatures, or physical damage during mechanical processing e.g. shelling, or over heating during drying. It is therefore vital for seed companies and farmers to test and ascertain seed viability to avoid losses of any kind. This study aimed at investigating the possibility of using hyperspectral imaging (HSI) technique to discriminate viable and nonviable corn seeds. A group of corn samples were heat treated by using microwave process while a group of seeds were kept as control group (untreated). The hyperspectral images of corn seeds of both groups were captured between 400 and 2500 nm wave range. Partial least squares discriminant analysis (PLS-DA) was built for the classification of aged (heat treated) and normal (untreated) corn seeds. The model showed highest classification accuracy of 97.6% (calibration) and 95.6% (prediction) in the SWIR region of the HSI. Furthermore, the PLS-DA and binary images were capable to provide the visual information of treated and untreated corn seeds. The overall results suggest that HSI technique is accurate for classification of viable and non-viable seeds with non-destructive manner.

Reduction of fumonisin B₁ in corn grits by twin-screw extrusion.

Science.gov (United States)

Jackson, Lauren S; Jablonski, Joseph; Bullerman, Lloyd B; Bianchini, Andreia; Hanna, Milford A; Voss, Kenneth A; Hollub, April D; Ryu, Dojin

2011-08-01

This study was designed to investigate the fate of fumonisins in flaking corn grits during twin-screw extrusion by measuring fumonisin B₁ (FB₁) and its analogs with a mass balance approach. Food grade corn grits and 2 batches of grits contaminated with FB₁ at 10 and 50 μg/g by Fusarium verticillioides M-2552 were processed with or without glucose supplementation (10%, w/w) with a twin-screw extruder. Extrusion reduced FB₁ in contaminated grits by 64% to 72% without glucose and 89% to 94% with added glucose. In addition, extrusion alone resulted in 26% to 73% reduction in the levels of fumonisin B₂ and fumonisin B₃, while levels of both mycotoxins were reduced by >89% in extruded corn grits containing 10% glucose. Mass balance analysis showed that 38% to 46% of the FB₁ species detected in corn extruded with glucose was N-(deoxy-D-fructos-1-yl)-FB₁, while 23% to 37% of FB₁ species detected in extruded corn grits with and without added glucose was bound to the matrix. It was also found that the hydrolyzed form of FB₁ was a minor species in extruded corn grits with or without added glucose, representing fumonisin analogues measured in this study. Research is needed to identify the reaction products resulting from extrusion processing of fumonisin-contaminated corn products. Twin-screw extrusion is widely used in food industry for its versatility. This technology may reduce the level of fumonisins in corn particularly with added glucose. Journal of Food Science © 2011 Institute of Food Technologists® No claim to original US government works.

Determination of the efficiency of diets for larval development in mass rearing Aedes aegypti (Diptera: Culicidae).

Science.gov (United States)

Gunathilaka, P A D H N; Uduwawala, U M H U; Udayanga, N W B A L; Ranathunge, R M T B; Amarasinghe, L D; Abeyewickreme, W

2017-11-23

Larval diet quality and rearing conditions have a direct and irreversible effect on adult traits. Therefore, the current study was carried out to optimize the larval diet for mass rearing of Aedes aegypti, for Sterile Insect Technique (SIT)-based applications in Sri Lanka. Five batches of 750 first instar larvae (L 1) of Ae. aegypti were exposed to five different concentrations (2-10%) of International Atomic Energy Agency (IAEA) recommended the larval diet. Morphological development parameters of larva, pupa, and adult were detected at 24 h intervals along with selected growth parameters. Each experiment was replicated five times. General Linear Modeling along with Pearson's correlation analysis were used for statistical treatments. Significant differences (P rate and success, sex ratio, adult success, fecundity and hatching rate of Ae. aegypti. The best quality adults can be produced at larval diet concentration of 10%. However, the 8% larval diet concentration was most suitable for adult male survival.

SWEET CORN FARMING: THE EFFECT OF PRODUCTION FACTOR, EFFICIENCY AND RETURN TO SCALE

Directory of Open Access Journals (Sweden)

Dwijatenaya I.B.M.A.

2017-10-01

Full Text Available This research aims to determine the effect of production factors on the sweet corn production, the efficiency of sweet corn farming, and the return to scale of sweet corn production. The sampling technique was taken by proportionate stratified random sampling method with the sample number of 57 people while the analyzer used was the program of Frointer 4.1c. The results show that the production factors of the land farm, seed, and fertilizer have a positive and significant effect on sweet corn production. On the other hand, labor production factors have a positive but not significant effect on sweet corn production. It also found that technical efficiency, price efficiency, and economic efficiency of sweet corn farming in Muara Wis Sub-district of Kutai Kartanegara Regency are not efficient yet. The return to scale of sweet corn yield has an increasing return to scale condition.

Corn stover fractions as a function of hybrid, maturity, site and year

Energy Technology Data Exchange (ETDEWEB)

Lizotte, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada); Lefsrud, M. [McGill Univ., Macdonald College, Ste-Anne-de-Bellevue, PQ (Canada). Dept. of Biosystems Engineering

2010-07-01

Corn stover is usually left on the ground following corn harvest so that it can be incorporated into the soil as organic matter and to protect against erosion. Part of the corn stover is oxidized in the atmosphere. Corn stover represents between 40 and 50 per cent of the dry matter (DM) contained in the aerial biomass of corn plants. Recent studies have shown that half of the corn stover could be harvested sustainably on low-sloping land under no-till practice. In Quebec, where 400,000 ha of corn are planted each year, corn stover could provide one million t DM of currently neglected biomass. Various hybrids of corn were monitored from early September to late November at 4 different sites during 2007, 2008 and 2009. Whole plants cut at 100 mm above the ground were collected weekly and separated into 7 fractions, notably the grain, the cob, the husk, the stalk below the ear, the stalk above the ear, the leaves below the ear and the leaves above the ear. In 2007, corn ears on average, were at 0.96 m above the ground at a site with low crop heat units (CHU). Hybrids grown in a warmer site were taller and their ears were 1.21 m above the ground. The DM partitioned in 7 components was 54 per cent grain, 14 per cent bottom stalk, 6 per cent top stalk, 5 per cent bottom leaves, 7 per cent top leaves, 5 per cent husk and 9 per cent cob. The total mass of fibre during harvest decreased from 8.9 to 6.6 t DM/ha for a low CHU hybrid and from 9.3 to 8.3 t DM/ha for a high CHU hybrid. Grain yield increased in 2008 from 3.8 to 7.6 t DM/ha over a 12-week period.

MYCOTOXIN CONTAMINATION ON CORN USED BY FEED MILLS IN INDONESIA

Directory of Open Access Journals (Sweden)

Budi Tangendjaja

2016-10-01

Full Text Available Mycotoxins which are secondary metabolites of fungi contaminate agricultural products such as corn and have deleterious effects on human and animal. The objective of this study was to evaluate the mycotoxin contamination on local and imported corn samples collected from different feed mills in Indonesia. Three hundred fifty six of corn samples (0.50 kg each were sent by several feed mills to the Indonesian Research Institute for Animal Production during 2005-2006. The background information accompanied with each sample was country/province of origins, harvesting seasons, postharvest drying methods, moisture levels, grades, and varieties. The samples were analyzed for various mycotoxins, i.e aflatoxin (AFL, ochratoxin (OCRA, zearalenone (ZEN, fumonisin (FUM, deoxynivalenol (DON, and T2 toxin using commercial kits, except for AFL which was analysed using a kit developed by the Indonesian Research Center for Veterinary Science. The results showed that average AFL level in the contaminated corn originated from Indonesia was 59 µg kg-1, almost 7 times higher than that imported from the USA or Argentina. Among the types of mycotoxins detected, FUM was the highest with an average of 1193 µg kg-1, followed by DON, ZEN and OCRA at level of 324, 22 and 2 µg kg-1, respectively. Mycotoxin levels in the contaminated local corn samples varied depending on the province of origins as well as harvesting seasons, postharvest drying methods, and moisture contents. The least mycotoxin contaminations were found on corn originated from NorthSumatra and Lampung with the AFL levels were < 20 and < 50 µg kg-1, respectively, lower than those from East Java, Central Java and South Sulawesi (64-87 µg kg-1. Mycotoxin levels, however, were less affected by grading made by feed mills and corn varieties. It is indicated that AFL was the most important mycotoxin as far as for animal feeding concerned, as it contaminated almost 50% of local corn with the level of

Update of distillers grains displacement ratios for corn ethanol life-cycle analysis.

Energy Technology Data Exchange (ETDEWEB)

Arora, S.; Wu, M.; Wang, M.; Energy Systems

2011-02-01

Production of corn-based ethanol (either by wet milling or by dry milling) yields the following coproducts: distillers grains with solubles (DGS), corn gluten meal (CGM), corn gluten feed (CGF), and corn oil. Of these coproducts, all except corn oil can replace conventional animal feeds, such as corn, soybean meal, and urea. Displacement ratios of corn-ethanol coproducts including DGS, CGM, and CGF were last updated in 1998 at a workshop at Argonne National Laboratory on the basis of input from a group of experts on animal feeds, including Prof. Klopfenstein (University of Nebraska, Lincoln), Prof. Berger (University of Illinois, Urbana-Champaign), Mr. Madson (Rapheal Katzen International Associates, Inc.), and Prof. Trenkle (Iowa State University) (Wang 1999). Table 1 presents current dry milling coproduct displacement ratios being used in the GREET model. The current effort focuses on updating displacement ratios of dry milling corn-ethanol coproducts used in the animal feed industry. Because of the increased availability and use of these coproducts as animal feeds, more information is available on how these coproducts replace conventional animal feeds. To glean this information, it is also important to understand how industry selects feed. Because of the wide variety of available feeds, animal nutritionists use commercial software (such as Brill Formulation{trademark}) for feed formulation. The software recommends feed for the animal on the basis of the nutritional characteristics, availability, and price of various animal feeds, as well as on the nutritional requirements of the animal (Corn Refiners Association 2006). Therefore, feed formulation considers both the economic and the nutritional characteristics of feed products.

The use of corn (ZEA MAYS) biomass in drying process

International Nuclear Information System (INIS)

Kricka, T.; Pliestic, S.

1996-01-01

The most important agricultural crop in the world, besides wheat and rice is corn. In the last 10 years, Republic of Croatia has produced about 2000000 tons of corn. Most of that is used for food and feed and for seed production and it is 1000000 tons in quantity. This quantity demands between 35000 to 40000 tons of oil. For the reason, this paper describes the possibilities of the substitution of oil with corn biomass after harvesting. (author)

Handling Indian corn on the cob (for the alcohol industry)

Energy Technology Data Exchange (ETDEWEB)

Podurazhnyi, Y K

1962-01-01

The corn grains are mechanically prepared from the cob shortly before malting, the wort is boiled at 142 to 144/sup 0/, and is made up of corn 34, beets 40, and molasses 26%, providing an alcohol liquor which contains on the average 7.34% (individual values as high as 8.6) ethanol. This application of corn on the cob incurs (on the base of prices in the Soviet Union) a saving of about 20% in ethanol manufacture.

Effects of nitrogen fertilizer application on greenhouse gas emissions and economics of corn production.

Science.gov (United States)

Kim, Seungdo; Dale, Bruce E

2008-08-15

Nitrogen fertilizer plays an important role in corn cultivation in terms of both economic and environmental aspects. Nitrogen fertilizer positively affects corn yield and the soil organic carbon level, but it also has negative environmental effects through nitrogen-related emissions from soil (e.g., N20, NOx, NO3(-) leaching, etc.). Effects of nitrogen fertilizer on greenhouse gas emissions associated with corn grain are investigated via life cycle assessment. Ecoefficiency analysis is also used to determine an economically and environmentally optimal nitrogen application rate (NAR). The ecoefficiency index in this study is defined as the ratio of economic return due to nitrogen fertilizer to the greenhouse gas emissions of corn cultivation. Greenhouse gas emissions associated with corn grain decrease as NAR increases at a lower NAR until a minimum greenhouse gas emission level is reached because corn yield and soil organic carbon level increase with NAR. Further increasing NAR after a minimum greenhouse gas emission level raises greenhouse gas emissions associated with corn grain. Increased greenhouse gas emissions of corn grain due to nitrous oxide emissions from soil are much higher than reductions of greenhouse gas emissions of corn grain due to corn yield and changes in soil organic carbon levels at a higher NAR. Thus, there exists an environmentally optimal NAR in terms of greenhouse gas emissions. The trends of the ecoefficiency index are similar to those of economic return to nitrogen and greenhouse gas emissions associated with corn grain. Therefore, an appropriate NAR could enhance profitability as well as reduce greenhouse gas emissions associated with corn grain.

Physiochemical Properties and Probiotic Survivability of Symbiotic Corn-Based Yogurt-Like Product.

Science.gov (United States)

Wang, Cuina; Zheng, Huajie; Liu, Tingting; Wang, Dawei; Guo, Mingruo

2017-09-01

Corn is a major grain produced in northern China. Corn-based functional food products are very limited. In this study, a symbiotic corn-based yogurt-like product was developed. Corn milk was prepared through grinding, extrusion and milling, and hydration processes. Corn extrudate was prepared under the optimized conditions of corn flour particle size fermented at 35 °C for 6 h using a probiotic starter culture containing L. plantarum. Chemical composition (%) of the symbiotic corn-based yogurt-like product was: total solids (17.13 ± 0.31), protein (1.12 ± 0.03), fat (0.30 ± 0.05), carbohydrates (15.14 ± 0.19), and ash (0.16 ± 0.02), respectively. pH value of this symbiotic product decreased from 4.50 ± 0.03 to 3.88 ± 0.13 and the population of L. plantarum declined from 7.8 ± 0.09 to 7.1 ± 0.14 log CFU/mL during storage at 4 °C. SDS-PAGE analysis showed that there were no changes in protein profile during storage. Texture and consistency were also stable during the period of this study. It can be concluded that a set-type corn-based symbiotic yogurt-like product with good texture and stability was successfully developed that would be a good alternative to the dairy yogurt. © 2017 Institute of Food Technologists®.

Preparation and In vitro Digestibility of Corn Starch Phosphodiester ...

African Journals Online (AJOL)

Purpose: To optimize the process conditions and analyze in vitro digestibility of corn starch phosphodiester prepared by sodium trimetaphosphate (STMP). Methods: By using response surface method, the effects of STMP concentration, pH, esterification temperature, and urea addition on digestion resistance of corn starch ...

Fungal protein from corn waste effluents : a model study

NARCIS (Netherlands)

Schellart, J.A.

1975-01-01

The purpose of this investigation was to study the microbiological aspects of the production of microbial protein ('single cell protein'; SCP) from corn waste effluents with simultaneous reduction of the COD of these effluents.

For practical reasons the corn waste water itself was

Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

International Nuclear Information System (INIS)

Mani, S.; Sokhansanj, S.; Tagore, S.; Turhollow, A.F.

2010-01-01

This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam 3 ). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

Thermophysical properties of conjugated soybean oil/corn stover biocomposites.

Science.gov (United States)

Pfister, Daniel P; Larock, Richard C

2010-08-01

Novel "green composites" have been prepared using a conjugated soybean oil-based resin and corn stover as a natural fiber. Corn stover is the residue remaining after grain harvest and it is estimated that approximately 75 million tons are available annually in the United States. The effect of the amount of filler, the length of the fiber, and the amount of the crosslinker on the structure and thermal and mechanical properties of the composites has been determined using Soxhlet extraction analysis, thermogravimetric analysis, dynamic mechanical analysis, and tensile testing. Increasing the amount of corn stover and decreasing the length of the fiber results in significant improvements in the mechanical properties of the composites. The Young's moduli and tensile strengths of the composites prepared range from 291 to 1398 MPa and 2.7 to 7.4 MPa, respectively. Water uptake data indicate that increasing the amount and fiber length of the corn stover results in significant increases in the absorption of water by the composites. The composites, containing 20 to 80 wt.% corn stover and a resin composed of 50 wt.% natural oil, contain 60 to 90 wt.% renewable materials and should find applications in the construction, automotive, and furniture industries. (c) 2010 Elsevier Ltd. All rights reserved.

CORN, LP Goldfield Approval

Science.gov (United States)

This November 19, 2015 letter from EPA approves the petition from CORN, LP, Goldfield facility, regarding non-grandfathered ethanol produced through a dry mill process, qualifying under the Clean Air Act for renewable fuel (D-code 6) RINs under the RFS pro

pH catalyzed pretreatment of corn bran for enhanced enzymatic arabinoxylan degradation

DEFF Research Database (Denmark)

Agger, Jane; Johansen, Katja Salomon; Meyer, Anne S.

2011-01-01

Corn bran is mainly made up of the pericarp of corn kernels and is a byproduct stream resulting from the wet milling step in corn starch processing. Through statistic modeling this study examined the optimization of pretreatment of corn bran for enzymatic hydrolysis. A low pH pretreatment (pH 2......, 150°C, 65min) boosted the enzymatic release of xylose and glucose and maximized biomass solubilization. With more acidic pretreatment followed by enzymatic hydrolysis the total xylose release was maximized (at pH 1.3) reaching ∼50% by weight of the original amount present in destarched corn bran......, but the enzyme catalyzed xylose release was maximal after pretreatment at approx. pH 2. The total glucose release peaked after pretreatment of approx. pH 1.5 with an enzymatic release of approx. 68% by weight of the original amounts present in destarched corn bran. For arabinose the enzymatic release...

Bio-oil and bio-char production from corn cobs and stover by fast pyrolysis

International Nuclear Information System (INIS)

Mullen, Charles A.; Boateng, Akwasi A.; Goldberg, Neil M.; Lima, Isabel M.; Laird, David A.; Hicks, Kevin B.

2010-01-01

Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are ∼20 MJ kg -1 , and densities >1.0 Mg m -3 ) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, ∼20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed 'farm scale' bio-refinery system. Bio-char yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields.

Private sector embedded water risk: Merging the corn supply chain network and regional watershed depletion

Science.gov (United States)

Kim, T.; Brauman, K. A.; Schmitt, J.; Goodkind, A. L.; Smith, T. M.

2016-12-01

Water scarcity in US corn farming regions is a significant risk consideration for the ethanol and meat production sectors, which comprise 80% of all US corn demand. Water supply risk can lead to effects across the supply chain, affecting annual corn yields. The purpose of our study is to assess the water risk to the US's most corn-intensive sectors and companies by linking watershed depletion estimates with corn production, linked to downstream companies through a corn transport model. We use a water depletion index as an improved metric for seasonal water scarcity and a corn sourcing supply chain model based on economic cost minimization. Water depletion was calculated as the fraction of renewable (ground and surface) water consumption, with estimates of more than 75% depletion on an annual average basis indicating a significant water risk. We estimated company water risk as the amount of embedded corn coming from three categories of water stressed counties. The ethanol sector had 3.1% of sourced corn grown from counties that were more than 75% depleted while the beef sector had 14.0%. From a firm perspective, Tyson, JBS, Cargill, the top three US corn demanding companies, had 4.5%, 9.6%, 12.8% of their sourced corn respectively, coming from watersheds that are more than 75% depleted. These numbers are significantly higher than the global average of 2.2% of watersheds being classified as more than 75% depleted. Our model enables corn using industries to evaluate their supply chain risk of water scarcity through modeling corn sourcing and watershed depletion, providing the private sector a new method for risk estimation. Our results suggest corn dependent industries are already linked to water scarcity risk in disproportionate amounts due to the spatial heterogeneity of corn sourcing and water scarcity.

Identifying drivers for consumer acceptance and purchase intent of corn tortilla.

Science.gov (United States)

Herrera-Corredor, J A; Saidu, J E P; Khachatryan, A; Prinyawiwatkul, W; Carballo-Carballo, A; Zepeda-Bautista, R

2007-11-01

The traditional production of corn tortilla has been modified by new processing technologies to make possible a commercial-scale production; this practice has resulted in products having sensory properties different from those produced by the traditional method. There is no published information on sensory attributes driving acceptance and purchase intent of corn tortillas. Identifying sensory drivers for acceptance and purchase intent of corn tortillas will help commercially produce products that satisfy consumers' expectations. A consumer study was conducted to evaluate acceptance and purchase intent of corn tortillas and determine drivers of acceptance and purchase intent of the products. Ten samples of corn tortillas were selected to represent a variety of corn tortillas available in the Mexican market. Three hundred Mexican consumers evaluated acceptability of appearance, color, thickness, rollability, resistance to tearing, aroma, chewiness, taste and aftertaste, and overall liking using a 9-point hedonic scale. Overall acceptance and purchase intent were determined with a yes/no scale. Analysis of variance and multivariate analysis of variance revealed that consumers were able to differentiate differences in sensory acceptability among 10 samples. For example, 2 homemade and 1 small commercial-scale samples, with an overall liking score of 6.6 to 6.7, were more acceptable than others. Rollability, resistance to tearing, and chewiness were attributes underlying overall differences among 10 samples. Attributes determining overall acceptance of corn tortillas were chewiness and overall liking. Purchase intent was influenced by overall appearance, rollability, chewiness, taste, and overall liking. This study revealed critical sensory attributes and their weights given by Mexican consumers when making decisions for acceptance and purchase intent of corn tortilla.

Turbulence, larval fish ecology and fisheries recruitment : a review of field studies

DEFF Research Database (Denmark)

MacKenzie, Brian

2000-01-01

, and recruitment in entire populations. One of the main findings is that field studies show contrasting effects of turbulence on feeding, growth and mortality rates in nature and on recruitment. Coincident and multiple variations in ecosystem processes, lack of understanding of how some of these processes (e......Fish recruitment varies widely between years but much of this variability cannot be explained by most models of fish population dynamics. In this review, I examine the role of environmental variability on fish recruitment, and ill particular how turbulence affects feeding and growth of larval fish.......g. larval diet composition, feeding behaviour, growth rates, prey patchiness) respond to turbulence, and unavoidable sampling artifacts are mainly responsible for this result. Upwelling as well as frontal processes appear important for larval fish growth and survival, and turbulence levels vary both within...

Performance of japanese quails fed feeds containing different corn and limestone particle sizes

Directory of Open Access Journals (Sweden)

DA Berto

2007-09-01

Full Text Available This study aimed at evaluating performance and egg quality of Japanese quails fed feeds containing different corn and limestone particle sizes. A total number of 648 birds in the peak of production was distributed in a random complete block experimental design, using a 2x3 factorial arrangement (2 corn particle sizes and 3 limestone particle sizes. Birds were designated to one of two blocks, with six replicates of 18 birds each. Mean geometric diameter (MGD values used were 0.617mm and 0.723mm (corn fine and coarse particle sizes, respectively, and 0.361mm, 0.721mm, and 0.947mm (limestone fine, intermediate and coarse particle sizes, respectively. The following treatments were applied: T1: fine corn feed, with 100% fine limestone; T2: fine corn feed, with 50% fine limestone and 50% intermediate limestone; T3: fine corn feed, with 50% fine limestone and 50% coarse limestone; T4: coarse corn feed, with 100% fine limestone; T5: coarse corn feed, with 50% fine limestone and 50% intermediate limestone; T6: coarse corn feed, with 50% fine limestone and 50% coarse limestone. The experiment lasted 112 days, consisting of 4 cycles of 28 days. No significant interaction was observed among corn and limestone particle sizes for any of the analyzed parameters. There were no significant effects (p>0.05 of the tested corn particle sizes on quail performance or egg quality. There were significant (p<0.05 isolated effects of limestone particle size only on the percentage of cracked eggs, which was reduced when birds fed 50% coarse limestone (0.947mm and 50% fine limestone (0.361mm as compared to those fed 100% fine limestone. Therefore, the inclusion of 50% coarse limestone (0.947mm is recommended for quail egg production.

Effects of Feeding Corn-lablab Bean Mixture Silages on Nutrient Apparent Digestibility and Performance of Dairy Cows

Directory of Open Access Journals (Sweden)

Yongli Qu

2013-04-01

Full Text Available This study estimated the fermentation characteristics and nutrient value of corn-lablab bean mixture silages relative to corn silages. The effects of feeding corn-lablab bean mixture silages on nutrient apparent digestibility and milk production of dairy cows in northern China were also investigated. Three ruminally cannulated Holstein cows were used to determine the ruminal digestion kinetics and ruminal nutrient degradability of corn silage and corn-lablab bean mixture silages. Sixty lactating Holstein cows were randomly divided into two groups of 30 cows each. Two diets were formulated with a 59:41 forage: concentrate ratio. Corn silage and corn-lablab bean mixture silages constituted 39.3% of the forage in each diet, with Chinese wildrye hay constituting the remaining 60.7%. Corn-lablab bean mixture silages had higher lactic acid, acetic acid, dry matter (DM, crude protein (CP, ash, Ca, ether extract concentrations and ruminal nutrient degradability than monoculture corn silage (p<0.05. Neutral detergent fiber (NDF and acid detergent fiber (ADF concentrations of corn-lablab bean mixture silages were lower than those of corn silage (p<0.05. The digestibility of DM, CP, NDF, and ADF for cows fed corn-lablab bean mixture silages was higher than for those fed corn silage (p<0.05. Feeding corn-lablab bean mixture silages increased milk yield and milk protein of dairy cows when compared with feeding corn silage (p<0.05. The economic benefit for cow fed corn-lablab bean mixture silages was 8.43 yuan/day/cow higher than that for that fed corn silage. In conclusion, corn-lablab bean mixture improved the fermentation characteristics and nutrient value of silage compared with monoculture corn. In this study, feeding corn-lablab bean mixture silages increased milk yield, milk protein and nutrient apparent digestibility of dairy cows compared with corn silage in northern China.

Effects of Plant Density on Sweet and Baby Corn (Hybrid KSC 403 Yield and Yield Components

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H Bavi

2016-07-01

Full Text Available Introduction Sweet corn is the one of the most important types of corn. There is a high amount of sugar in the endosperm of sweet corn than dent corn. Baby corn is the ear of corn that is being harvested in the silking stage before the end of pollination. This crop has an interesting using methods as salad, conserve production and vegetative consumption. Both two sweet and baby corn is obtained from one plant in different growth stages and could be harvested from one corn hybrid. Best yield and quality of baby corn is obtained from sweet corn hybrids, because of high amounts of sugar in the grains and ears. Sweet corn and baby corn could be harvested at early dough stage (with about 30 % of humidity and early silking stage before the pollination is completed, respectively. Plant density is the most important factor in growing corn, especially in sweet and baby corn. Khuzestan province is one of the main regions of corn production in Iran. In Khuzestan, forage and silage corn have the most production among the summer crops. Corn is planted in two planting date in Khuzestan: early spring and early summer. Spring corn planting produces little grain yield due to Simultaneity of silking stage with hot early summer days. Because of little production and little research about sweet and baby corn, this study was performed and designed. Materials and Methods In order to investigate the effects of plant density and harvesting method on sweet corn and baby corn yield, an experiment was performed during 2012-13, in research farm of Ramin Agriculture and Natural Resources University of Khuzestan, located in southwest of Iran. In this experiment, four plant densities (7, 9, 11 and 13 plants.m-2 and two harvesting methods (baby corn and sweet corn were investigated in an RCB statistical design with four replications. The KSC 403 hybrid was used and investigated in the experiment, as a sweet corn hybrid. Statistical analysis was performed using SAS 9.1 through

7 CFR 319.24a - Administrative instructions relating to entry of corn into Guam.

Science.gov (United States)

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Administrative instructions relating to entry of corn...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Corn Diseases Quarantine § 319.24a Administrative instructions relating to entry of corn into Guam. Corn may be...

Study on the Effect of cellulolytic strain MYB3 for Corn Stover Fermentation

Science.gov (United States)

Yan, Han; Bai, Bing; Cheng, Xiao-Xiao; Li, Guang-Chun; Huang, Shi-Chen; Piao, Chun-Xiang

2018-03-01

The effects of corn stover fermentation with the Bacillus megaterium MYB3 was studied in this paper. The results showed that the decomposition rates of cellulose and hemicellulose were 49.6%, 43.46% after 20 days respectively, after fermentation, pH was changed to 5.68, and adjusted to corn stover initial pH 3 to achieve the purpose of sterilization. The decomposition rate was significantly increased by adding corn flour. After adjusting fermentation composes with the ratio of the corn stove to corn flour was 15 : 1, the decomposition rate of cellulose would be 52.37% for 10 days.

7 CFR 319.24-1 - Applications for permits for importation of corn.

Science.gov (United States)

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Applications for permits for importation of corn. 319... PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Corn Diseases Regulations Governing Entry of Indian Corn Or Maize § 319.24-1 Applications for permits for importation of...

Larval developmental rate, metabolic rate and future growth performance in Atlantic salmon

DEFF Research Database (Denmark)

Serrano, Jonathan Vaz; Åberg, Madelene; Gjoen, Hans Magnus

2009-01-01

, quantified as time to first feeding, and growth in later stages was demonstrated in Atlantic salmon (Salmo salar L.). The observed relationship between future growth and larval developmental rate suggests that sorting larvae by time to first feeding can be a potential tool to optimize feeding strategies...... and growth in commercial rearing of Atlantic salmon. Furthermore, the link between larval standard metabolic rate and developmental rate and future growth is discussed in the present study....

Fate of Fumonisin B1 in Naturally Contaminated Corn during Ethanol Fermentation

Science.gov (United States)

Bothast, R. J.; Bennett, G. A.; Vancauwenberge, J. E.; Richard, J. L.

1992-01-01

Two lots of corn naturally contaminated with fumonisin B1 (15 and 36 ppm) and a control lot (no fumonisin B1 detected) were used as substrates for ethanol production in replicate 8.5-liter yeast fermentations. Ethanol yields were 8.8% for both the control and low-fumonisin corn, while the high-fumonisin corn contained less starch and produced 7.2% ethanol. Little degradation of fumonisin occurred during fermentation, and most was recovered in the distillers' grains, thin stillage, and distillers' solubles fractions. No toxin was detected in the distilled alcohol or centrifuge solids. Ethanol fermentation of fumonisin-contaminated corn coupled with effective detoxification of distillers' grains and aqueous stillage is suggested as a practical process strategy for salvaging contaminated corn. PMID:16348623

Effects of temperature and dietary nitrogen on genetic variation and covariation in gypsy moth larval performance traits

Directory of Open Access Journals (Sweden)

Janković-Tomanić Milena

2012-01-01

Full Text Available To assess the plastic and genetic components of variation in responses of gypsy moth (Lymantria dispar 4th instar larvae to temperature and food quality, we applied a split-family four-environment experimental design where full-sibs were reared on two constant temperatures (23°C and 28°C and two concentrations of dietary nitrogen (1.5 and 3.7% dry weight. A temperature of 28°C and low dietary nitrogen decreased larval weight and prolonged larval developmental time, while viability was not affected. Only a marginally significant interaction between the two environmental factors was found for larval weight. The broad-sense heritability for larval developmental time did not change across environments, and across-environment genetic correlations were close to one. Heritability for larval weight depended on environmental and across-environmental genetic correlations that were not significant. There was no evidence of a trade-off between developmental time and larval weight. The implications of the obtained results for the evolution of phenotypic plasticity in complex environments are discussed. [Acknowledgments. This work was supported by Ministry of Education and Science of Serbia, grant No. 173027.

Diatom production in the marine environment : implications for larval fish growth and condition

DEFF Research Database (Denmark)

St. John, Michael; Clemmesen, C.; Lund, T.

2001-01-01

To test the effects of diatom production on larval fish growth and condition. laboratory experiments were performed with larval North Sea cod reared on different algal food chains. These food chains were based on cultures of (a) the diatoms Skeletonema costatum and Thalassiosira weissflogii: (b....../omega6 fatty acids in the algal source had no significant effect. The highest and lowest growth rates were observed in food chains based on H. triquetra and T. weissflogii. respectively (means for days 14-16 of 4.0 and - 4.7). The mixed diatom/dinoflagellate diet resulted in inter- mediate growth rates...... and condition. Regressions of growth rates against EPA and DHA content indicated no inhibitory effect of diatom production on growth in larval cod...

Eggshells as an index of aedine mosquito production. 2: Relationship of Aedes taeniorhynchus eggshell density to larval production.

Science.gov (United States)

Addison, D S; Ritchie, S A; Webber, L A; Van Essen, F

1992-03-01

To test if eggshell density could be used as an index of aedine mosquito production, we compared eggshell density with the larval production of Aedes taeniorhynchus in Florida mangrove basin forests. Quantitative (n = 7) and categorical (n = 34) estimates of annual larval production were regressed against the number of eggshells per cc of soil. Significant regressions were obtained in both instances. Larval production was concentrated in zones with the highest eggshell density. We suggest that eggshell density and distribution can be used to identify oviposition sites and the sequence of larval appearance.

Proteolytic activity regarding Sarconesiopsis magellanica (Diptera: Calliphoridae) larval excretions and secretions.

Science.gov (United States)

Pinilla, Yudi T; Moreno-Pérez, Darwin A; Patarroyo, Manuel A; Bello, Felio J

2013-12-01

Sarconesiopsis magellanica (Diptera: Calliphoridae) is a medically important necrophagous fly which is used for establishing the post-mortem interval. Diptera maggots release proteolytic enzymes contained in larval excretion and secretion (ES) products playing a key role in digestion. Special interest in proteolytic enzymes has also been aroused regarding understanding their role in wound healing since they degrade necrotic tissue during larval therapy. This study was thus aimed at identifying and characterising S. magellanica proteolytic enzyme ES products for the first time. These products were obtained from first-, second- and third-instar larvae taken from a previously-established colony. ES proteins were separated by SDS-PAGE and their proteolytic activity was characterised by zymograms and inhibition assays involving BAPNA (Nα-benzoyl-dl-Arg-p-nitroanilide) and SAPNA substrates, using synthetic inhibitors. The protein profile ranged from ∼69kDa to ∼23kDa; several of them coincided with the Lucilia sericata ES protein profile. Serine-protease hydrolysis activity (measured by zymogram) was confirmed when a ∼25kDa band disappeared upon ES incubation with PMSF inhibitor at pH 7.8. Analysis of larval ES proteolytic activity on BAPNA and SAPNA substrates (determined by using TLCK and TPCK specific inhibitors) suggested a greater amount of trypsin-like protease. These results support the need for further experiments aimed at validating S. magellanica use in larval therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

75 FR 56911 - Request for Public Comment on the United States Standards for Corn

Science.gov (United States)

2010-09-17

... Public Comment on the United States Standards for Corn AGENCY: Grain Inspection, Packers and Stockyards... Standards and grading procedures for corn under the United States Grain Standards Act (USGSA). Since the standards were last revised, the use of corn for ethanol and the number of different varieties of corn has...

Effect of corn cobs concentration on xylanase biosynthesis by ...

African Journals Online (AJOL)

Corn cobs, an indigenous carbon source, were tested as substrate by Aspergillus niger for optimum synthesis of xylanase using the submerged fermentation technique. The trials for xylanase production were conducted at three concentration levels (2.5, 3.0 and 3.5%) of corn cobs, four different fermentation temperatures ...

Regional and seasonal differences in growth of larval North Sea herring (clupea harengus L.) estimated by otolith microstructure analysis

DEFF Research Database (Denmark)

Munk, Peter; Heath, Mike; Skaarup, Bo

1991-01-01

The ecology processes of the larval life of autumn-spawned North Sea herring have been studied in a multidisciplinary and internationally coordinated research programme (ACE). The programme focused on larval advection and the importance of the autumn/winter circulation in determining larval distr...

Larval connectivity studies in the Western Iberian Peninsula

Science.gov (United States)

Dubert, Jesus; Nolasco, Rita; Queiroga, Henrique

2010-05-01

The study of the connectivity between populations is one of the 'hot' applications of numerical models of the ocean circulation. An IBM (Individual Based model) was developed, using Carcinus manenas larvae crab as a model. A set of particles was used as a representation of larvae, in order to study their larval life cycle, including the larval growth, larval mortality (both depending on temperature and salinity), larval dispersal by currents, diel vertical migration, and larval recruitment. The life cycle of every larvae in the ocean, was modeled from zoeae 1 stage to megalopae stage, during typical periods of 30-50 days. Larvae were initialized in 14 estuarine systems of the Atlantic Western Iberian Peninsula, from January to July. In every period, a number of 225 larvae are initialized in everyone of the 14 considered estuaries, with fortynighly periodicity. The larvae evolves during the (variable, depending mainly on temperature) period of growth in the ocean, and when a larvae reach the age for recruit, if it is located in the neighborhood of the considered estuarine systems, the larvae is accounted as a recruited larvae in that place. With this methodology, a connectivity matrix can be computed, acconting for the 225 larvae emitted in every estuary, the number of larvae that reaches the every place. The connectivity matrix depends strongly on the current regime along the Atlantic coast of Iberian Peninsula, and has been calculated for the present circulation, for the period 2001 to 2009, for runs with realistic forcing with NCEP2 and Quikscat (for winds) forcing. The connectivity matrix, have also been calculated for climatological runs. For the present climatological conditions, it is observed the prevalence of southward transport for the period January-July, because the prevalence of Northerly winds along the west coast of IP in the COADS present time climatology. Strong dispersal is observed at the Northern estuaries, during winter with strong loss of

Effect of emamectin benzoate on mortality, proboscis extension, gustation and reproduction of the corn earworm, Helicoverpa zea.

Science.gov (United States)

López, Juan D; Latheef, M A; Hoffmann, W C

2010-01-01

Newly emerged corn earworm adults, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) require a carbohydrate source from plant or other exudates and nectars for dispersal and reproduction. Adults actively seek and forage at feeding sites upon eclosion in the habitat of the larval host plant or during dispersal to, or colonization of, a suitable reproductive habitat. This nocturnal behavior of H. zea has potential for exploitation as a pest management strategy for suppression using an adult feeding approach. This approach entails the use of a feeding attractant and stimulant in combination with a toxicant that when ingested by the adult will either reduce fecundity/fertility at sub-lethal dosages or kill the adult. The intent of this study was to assess reproductive inhibition and toxicity of emamectin benzoate on H. zea when ingested by the adults when mixed in ppm active ingredient (wt:vol) with 2.5 M sucrose as a feeding stimulant. Because the mixture has to be ingested to function, the effect of emamectin benzoate was also evaluated at sub-lethal and lethal concentrations on proboscis extension and gustatory response of H. zea in the laboratory. Feral males captured in sex pheromone-baited traps in the field were used for toxicity evaluations because they were readily available and were more representative of the field populations than laboratory-reared adults. Laboratory-reared female moths were used for reproduction effects because it is very difficult to collect newly emerged feral females from the field. Emamectin benzoate was highly toxic to feral H. zea males with LC(50) values (95% CL) being 0.718 (0.532-0.878), 0.525 (0.316-0.751), and 0.182 (0.06-0.294) ppm for 24, 48 and 72 h responses, respectively. Sub-lethal concentrations of emamectin benzoate did not significantly reduce proboscis extension response of feral males and gustatory response of female H. zea. Sublethal concentrations of emamectin benzoate significantly reduced percent larval hatch of

Offshore-onshore linkages in the larval life history of sole in the Gulf of Lions (NW-Mediterranean)

Science.gov (United States)

Morat, Fabien; Letourneur, Yves; Blamart, Dominique; Pécheyran, Christophe; Darnaude, Audrey M.; Harmelin-Vivien, Mireille

2014-08-01

Understanding individual dispersion from offshore natal areas to coastal nurseries during pelagic larval life is especially important for the sustainable management of exploited marine fish species. For several years, the hatching period, the larval life duration, the average growth rate and the otolith chemical composition (δ13C, δ18O, Sr:Ca and Ba:Ca) during the larval life were studied for young of the year (YOY) of sole collected in three main nurseries of the Gulf of Lions (GoL) (Thau, Mauguio and Berre). We investigated the spatial variation in the origin of the sole larvae which colonised the nurseries around the GoL, and whether temporal differences in environmental conditions during this life stage affected growth and larval life duration. The hatching period ranges from October to March, depending on year and site. Average ages at metamorphosis varied between 43 and 50 days, with the lowest and highest values consistently found for Mauguio and Berre, respectively. Otolith growth rates ranged between 2.7 and 3.2 μm d-1, with the lowest values in Thau and Mauguio and the highest in Berre. Otolith chemical composition during the larval life also varied, suggesting contrasted larval environmental histories in YOY among nurseries. In fishes from Berre and Mauguio, larval life was more influenced by the Rhône River, showing consistently higher larval Ba:Ca ratios (10/23 μmol mol-1) and lower δ13C (-6.5/-6.1‰) and δ18O values (-1.6/0.1‰) than for Thau (with Ba:Ca ratios < 8 μmol mol-1, δ13C ˜-2.3‰ and δ18O ˜1.5‰). Differences in larval otolith composition were observed for 2004, with higher Ba:Ca and lower δ13C and δ18O values than in the two other years. These differences were explained by changes in composition and chemical signatures of water masses after an exceptional flooding event of the Rhône River in late 2003.

Process-based models of feeding and prey selection in larval fish

DEFF Research Database (Denmark)

Fiksen, O.; MacKenzie, Brian

2002-01-01

believed to be important to prey selectivity and environmental regulation of feeding in fish. We include the sensitivity of prey to the hydrodynamic signal generated by approaching larval fish and a simple model of the potential loss of prey due to turbulence whereby prey is lost if it leaves...... jig dry wt l(-1). The spatio-temporal fluctuation of turbulence (tidal cycle) and light (sun height) over the bank generates complex structure in the patterns of food intake of larval fish, with different patterns emerging for small and large larvae....

Larval Performance in the Context of Ecological Diversification and Speciation in Lycaeides Butterflies

Directory of Open Access Journals (Sweden)

Cynthia F. Scholl

2012-01-01

Full Text Available The role of ecology in diversification has been widely investigated, though few groups have been studied in enough detail to allow comparisons of different ecological traits that potentially contribute to reproductive isolation. We investigated larval performance within a species complex of Lycaeides butterflies. Caterpillars from seven populations were reared on five host plants, asking if host-specific, adaptive larval traits exist. We found large differences in performance across plants and fewer differences among populations. The patterns of performance are complex and suggest both conserved traits (i.e., plant effects across populations and more recent dynamics of local adaptation, in particular for L. melissa that has colonized an exotic host. We did not find a relationship between oviposition preference and larval performance, suggesting that preference did not evolve to match performance. Finally, we put larval performance within the context of several other traits that might contribute to ecologically based reproductive isolation in the Lycaeides complex. This larger context, involving multiple ecological and behavioral traits, highlights the complexity of ecological diversification and emphasizes the need for detailed studies on the strength of putative barriers to gene flow in order to fully understand the process of ecological speciation.

Polycystic echinococcosis in Colombia: the larval cestodes in infected rodents.

Science.gov (United States)

Morales, G A; Guzman, V H; Wells, E A; Angel, D

1979-07-01

Described are the characteristics of the polycystic larval cestodes found in an endemic area of echinococcosis in the Easter Plains of Colombia and the tissue reaction evoked in infected rodents. Of 848 free-ranging animals examined, polycystic hydatids were found in 44/93 Cuniculus paca and 1/369 Proechimys sp. None of 20 Dasyprocta fuliginosa examined was infected, but hunters provided a heart with hydatid cysts and information about two additional animals with infected livers. Recognition of an endemic area of polycystic echinococcosis provides a means to investigate the life cycle of the parasites and to study the histogenesis of the larval cestodes in susceptible laboratory animals.

INOCULATION OF DIAZOTROPHIC BACTERIA AND NITROGEN FERTILIZATION IN TOPDRESSING IN IRRIGATED CORN

Directory of Open Access Journals (Sweden)

VANESSA ZIRONDI LONGHINI

2016-01-01

Full Text Available Corn is a nitrogen-intensive crop, and the use of management practices such as inoculation of the seed with diazotrophic bacteria, which can maximize crop productivity and reduce the need of nitrogen fertilizers, may result in lower production costs. The present study aimed to evaluate the effect of inoculation of corn seed with Azospirillum brasilense and controlled addition of nitrogen to topdressing on the nutrition, production components, and productivity of crop grain. The experimental design was a randomized block design, with four replications in a 2 × 5 factorial scheme. The treatments consisted of inoculation or not of corn seed with A. brasilense (at 100 mL per 25 kg of seed and five nitrogen (N levels in topdressing (0, 30, 60, 90, and 120 kg N ha-1 from urea [45% N] were applied when the corn was in the phenological growth stage V6. Foliar macronutrients, foliar chlorophyll index (FCI, production components, and yield of corn grain were valuated. Inoculation of corn seeds with A. brasilense increased plant height and grain yield. Fertilization in topdressing, with N levels up to 120 kg ha-1, linearly increased the foliar nutrients and productivity of corn cultivated in the spring/summer in the low-altitude Cerrado region of Brazil.

Cellulose conversion of corn pericarp without pretreatment.

Science.gov (United States)

Kim, Daehwan; Orrego, David; Ximenes, Eduardo A; Ladisch, Michael R

2017-12-01

We report enzyme hydrolysis of cellulose in unpretreated pericarp at a cellulase loading of 0.25FPU/g pericarp solids using a phenol tolerant Aspergillus niger pectinase preparation. The overall protein added was 5mg/g and gave 98% cellulose conversion in 72h. However, for double the amount of enzyme from Trichoderma reesei, which is significantly less tolerant to phenols, conversion was only 16%. The key to achieving high conversion without pretreatment is combining phenol inhibition-resistant enzymes (such as from A. niger) with unground pericarp from which release of phenols is minimal. Size reduction of the pericarp, which is typically carried out in a corn-to-ethanol process, where corn is first ground to a fine powder, causes release of highly inhibitory phenols that interfere with cellulase enzyme activity. This work demonstrates hydrolysis without pretreatment of large particulate pericarp is a viable pathway for directly producing cellulose ethanol in corn ethanol plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Corn content of French fry oil from national chain vs. small business restaurants.

Science.gov (United States)

Jahren, A Hope; Schubert, Brian A

2010-02-02

Several issues, ranging from sustainability to health, may interest the consumers in the corn content of their food. However, because restaurants are excluded from the Nutrition Labeling and Education Act of 1990, national chain restaurants provide nonspecific ingredient information and small businesses supply none. We measured the carbon isotope composition of fry oil in French fries purchased from 68 (67%) of the 101 national chain fast food restaurants on Oahu (i.e., McDonald's, Burger King, Wendy's, Arby's, and Jack in the Box), and paired this with a similar number of small businesses (n = 66) to calculate minimum percent contribution of corn to total fry oil. We found that the majority (69%) of the national chain restaurants served fries containing corn oil, whereas this was true for only a minority (20%) of the small businesses. Corn oil is more expensive than soybean oil (for example) when purchased from a small business supplier, suggesting that large-scale corporate agreements are necessary to make corn oil frying cost-effective. When considering French fry oil along with corn-fed beef and chicken, as well as high-fructose corn syrup-sweetened soda, we see the pervasive influence of corn as an ingredient in national chain fast food.

Effects of different mechanized soil fertilization methods on corn nutrient accumulation and yield

Science.gov (United States)

Shi, Qingwen; Bai, Chunming; Wang, Huixin; Wu, Di; Song, Qiaobo; Dong, Zengqi; Gao, Depeng; Dong, Qiping; Cheng, Xin; Zhang, Yahao; Mu, Jiahui; Chen, Qinghong; Liao, Wenqing; Qu, Tianru; Zhang, Chunling; Zhang, Xinyu; Liu, Yifei; Han, Xiaori

2017-05-01

Aim: Experiments for mechanized corn soil fertilization were conducted in Faku demonstration zone. On this basis, we studied effects on corn nutrient accumulation and yield traits at brown soil regions due to different mechanized soil fertilization measures. We also evaluated and optimized the regulation effects of mechanized soil fertilization for the purpose of crop yield increase and production efficiency improvement. Method: Based on the survey of soil background value in the demonstration zone, we collected plant samples during different corn growth periods to determine and make statistical analysis. Conclusions: Decomposed cow dung, when under mechanical broadcasting, was able to remarkably increase nitrogen and potassium accumulation content of corns at their ripe stage. Crushed stalk returning combined with deep tillage would remarkably increase phosphorus accumulation content of corn plants. When compared with top application, crushed stalk returning combined with deep tillage would remarkably increase corn thousand kernel weight (TKW). Mechanized broadcasting of granular organic fertilizer and crushed stalk returning combined with deep tillage, when compared with surface application, were able to boost corn yield in the in the demonstration zone.

Kinetic study of corn straw pyrolysis: comparison of two different three-pseudocomponent models.

Science.gov (United States)

Li, Zhengqi; Zhao, Wei; Meng, Baihong; Liu, Chunlong; Zhu, Qunyi; Zhao, Guangbo

2008-11-01

With heating rates of 20, 50 and 100 K min(-1), the thermal decomposition of corn straw samples (corn stalks skins, corn stalks cores, corn bracts and corn leaves) were studied using thermogravimetric analysis. The maximum pyrolysis rates increased with the heating rate increasing and the temperature at the peak pyrolysis rate also increased. Assuming the addition of three independent parallel reactions, corresponding to three pseudocomponents linked to the hemicellulose, cellulose and lignin, two different three-pseudocomponent models were used to simulate the corn straw pyrolysis. Model parameters of pyrolysis were given. It was found that the three-pseudocomponent model with n-order kinetics was more accurate than the model with first-order kinetics at most cases. It showed that the model with n-order kinetics was more accurate to describe the pyrolysis of the hemicellulose.

Bio-oil and bio-char production from corn cobs and stover by fast pyrolysis

Energy Technology Data Exchange (ETDEWEB)

Mullen, Charles A.; Boateng, Akwasi A.; Goldberg, Neil M.; Hicks, Kevin B. [Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 E. Mermaid Lane, Wyndmoor, PA 19038 (United States); Lima, Isabel M. [Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 1100 Robert E. Lee Blvd., New Orleans, LA 70124 (United States); Laird, David A. [National Soil Tilth Laboratory, U.S. Agricultural Research Service, U.S. Department of Agriculture, 2110 University Blvd., Ames, IA 50011 (United States)

2010-01-15

Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are {proportional_to}20 MJ kg{sup -1}, and densities >1.0 Mg m{sup -3}) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, {proportional_to}20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed ''farm scale'' bio-refinery system. Bio-char yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields. (author)

Predator-induced larval cloning in the sand dollar Dendraster excentricus: might mothers matter?

Science.gov (United States)

Vaughn, Dawn

2009-10-01

Predator-induced cloning in echinoid larvae, with reduced size a consequence of cloning, is a dramatic modification of development and a novel response to risks associated with prolonged planktonic development. Recent laboratory studies demonstrate that exposure to stimuli from predators (i.e., fish mucus) induces cloning in the pluteus larvae (plutei) of Dendraster excentricus. However, the timing and incidence of cloning and size reduction of unrelated conspecific plutei differed across experiments. A variable cloning response suggests the effects of such factors as cue quality, egg provisioning, maternal experience, and genetic background, indicating that the potential advantages of cloning as an adaptive response to predators are not available to all larvae. This study tested the hypothesis that cloning in D. excentricus plutei is maternally influenced. Plutei from three half-sibling larval families (different mothers, same father) were exposed to fish mucus for 9 days during early development. Cloning was inferred in a percentage of plutei from each family; however, the rate and success of cloning differed significantly among the larval half-siblings. Unexpectedly, all mucus-treated plutei were smaller and developmentally delayed when compared to all plutei reared in the absence of a mucus stimulus. Thus, while the results from this study support the hypothesis of an influence of mothers on cloning of larval offspring, reduced larval size was a uniform response to fish mucus and did not indicate an effect of mothers. Hypotheses of the developmental effects of fish mucus on larval size with or without successful cloning are discussed.

[Super sweet corn hybrids adaptability for industrial processing. I freezing].

Science.gov (United States)

Alfonzo, Braunnier; Camacho, Candelario; Ortiz de Bertorelli, Ligia; De Venanzi, Frank

2002-09-01

With the purpose of evaluating adaptability to the freezing process of super sweet corn sh2 hybrids Krispy King, Victor and 324, 100 cobs of each type were frozen at -18 degrees C. After 120 days of storage, their chemical, microbiological and sensorial characteristics were compared with a sweet corn su. Industrial quality of the process of freezing and length and number of rows in cobs were also determined. Results revealed yields above 60% in frozen corns. Length and number of rows in cobs were acceptable. Most of the chemical characteristics of super sweet hybrids were not different from the sweet corn assayed at the 5% significance level. Moisture content and soluble solids of hybrid Victor, as well as total sugars of hybrid 324 were statistically different. All sh2 corns had higher pH values. During freezing, soluble solids concentration, sugars and acids decreased whereas pH increased. Frozen cobs exhibited acceptable microbiological rank, with low activities of mesophiles and total coliforms, absence of psychrophiles and fecal coliforms, and an appreciable amount of molds. In conclusion, sh2 hybrids adapted with no problems to the freezing process, they had lower contents of soluble solids and higher contents of total sugars, which almost doubled the amount of su corn; flavor, texture, sweetness and appearance of kernels were also better. Hybrid Victor was preferred by the evaluating panel and had an outstanding performance due to its yield and sensorial characteristics.

Protective effects of flavonoids from corn silk on oxidative stress ...

African Journals Online (AJOL)

Protective effects of flavonoids from corn silk on oxidative stress induced by ... The present study aims at exploring the effects of flavonoids from corn silk (FCS) on oxidative stress induced by exhaustive exercise in mice. ... from 32 Countries:.

Habitat use by larval fishes in a temperate South African surf zone

Science.gov (United States)

Watt-Pringle, Peter; Strydom, Nadine A.

2003-12-01

Larval fishes were sampled in the Kwaaihoek surf zone on the south east coast of South Africa. On six occasions between February and May 2002, larval fishes were collected in two habitat types identified in the inner surf zone using a modified beach-seine net. The surf zone habitats were classified as either sheltered trough areas or adjacent exposed surf areas. Temperature, depth and current measurements were taken at all sites. Trough habitats consisted of a depression in surf topography characterised by reduced current velocities and greater average depth than adjacent surf areas. In total, 325 larval fishes were collected. Of these, 229 were collected in trough and 96 in surf habitats. At least 22 families and 37 species were represented in the catch. Dominant families were the Mugilidae, Sparidae, Atherinidae, and Engraulidae. Dominant species included Liza tricuspidens and Liza richardsonii (Mugilidae), Rhabdosargus holubi and Sarpa salpa (Sparidae), Atherina breviceps (Atherinidae) and Engraulis japonicus (Engraulide). Mean CPUE of postflexion larvae of estuary-dependent species was significantly greater in trough areas. The proportion of postflexion larval fishes in trough habitat was significantly greater than that of preflexion stages, a result that was not apparent in surf habitat sampled. CPUE of postflexion larvae of estuary-dependent fishes was negatively correlated with current magnitude and positively correlated with habitat depth. Mean body length of larval fishes was significantly greater in trough than in surf habitats. These results provide evidence that the CPUE of postflexion larvae of estuary-dependent fishes is higher in trough habitat in the surf zone and this may be indicative of active habitat selection for areas of reduced current velocity/wave action. The implications of this behaviour for estuarine recruitment processes are discussed.

Assessing the toxicity of sediments using the medaka embryo-larval assay and 2 other bioassays.

Science.gov (United States)

Barhoumi, Badreddine; Clérandeau, Christelle; Landi, Laure; Pichon, Anaïk; Le Bihanic, Florane; Poirier, Dominique; Anschutz, Pierre; Budzinski, Hélène; Driss, Mohamed Ridha; Cachot, Jérôme

2016-09-01

Sediments are sinks for aquatic pollutants, and analyzing toxicity in such complex matrices is still challenging. To evaluate the toxicity of bioavailable pollutants accumulated in sediments from the Bizerte lagoon (Tunisia), a novel assay, the medaka embryo-larval assay by sediment contact, was applied. Japanese medaka (Oryzias latipes) embryos were incubated in direct contact with sediment samples up to hatching. Lethal and sublethal adverse effects were recorded in embryos and larvae up to 20 d postfertilization. Results from medaka embryo-larval assay were compared with cytotoxicity (Microtox®), genotoxicity (SOS chromotest), and pollutant content of sediments. The results highlight differences in the contamination profile and toxicity pattern between the different studied sediments. A significant correlation was shown between medaka embryo-larval assay by sediment contact and SOS chromotest responses and concentrations of most organic pollutants studied. No correlation was shown between pollutant levels and Microtox. According to the number of sediment samples detected as toxic, medaka embryo-larval assay by sediment contact was more sensitive than Microtox, which in turn was more sensitive than the SOS chromotest; and medaka embryo-larval assay by sediment contact allowed sediment toxicity assessment of moderately polluted sediments without pollutant extraction and using an ecologically realistic exposure scenario. Although medaka embryo-larval assay by sediment contact should be tested on a larger sample set, the results show that it is sensitive and convenient enough to monitor the toxicity of natural sediments. Environ Toxicol Chem 2016;35:2270-2280. © 2016 SETAC. © 2016 SETAC.

Large-scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

KAUST Repository

Williamson, David H.; Harrison, Hugo B.; Almany, Glenn R.; Berumen, Michael L.; Bode, Michael; Bonin, Mary C.; Choukroun, Severine; Doherty, Peter J.; Frisch, Ashley J.; Saenz-Agudelo, Pablo; Jones, Geoffrey P.

2016-01-01

Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers (Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60–220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations.