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Sample records for corn le rendement

  1. Le rendement énergétique de la production d’éthanol à partir de maïs

    NASA Astrophysics Data System (ADS)

    Chavanne, Xavier; Frangi, Jean-Pierre

    2008-05-01

    This article establishes the primary energy balance for making ethanol out of corn in the USA, calculated from the farm to the fuel station, following a methodology described in Chavanne and Frangi (C. R. Geoscience 339 (2007) 519-535). Raw data (direct energy and material consumption as well as their heat value and external costs) come from published papers related to this topic, technical textbooks, as well as reports from the US Departments of Agriculture and Energy. For the 2001 harvest, over the area producing more than 90% of ethanol and for the 2005 network of working refineries, 100 J of ethanol and recovery of by-products (the energy saved by the replacement of animal feed by these by-products is around 12% of the ethanol heat value) needed 86 ± 3 J of energy spending, of which more than 50 J is natural gas and 62 J is used in refineries. A third of the area of Nebraska corn must be irrigated with water pumped from underground, at an added cost of 26 ± 3 J. In 1996, the extra drying required, because of heavy rains, added 6 J. By comparison, 100 J of gasoline cost less than 25 J to be produced out of crude oil. Complementary studies of resource availability are not performed here. The largest possible reduction in energy costs can be achieved at the refinery stage, by fermenting by-products, gas residues, (from 62 J to around 12 J). The article gives also an expression for the expenditure to enable comparison between different energy systems, including everything from biomass to transport. For the ethanol case, the average cost is 130 J for 100 J of corn grain heat.

  2. Effects of refuges on the evolution of resistance to transgenic corn by western corn rootworm, Diabrotica virgifera virgifera LeConte

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diabrotica virgifera virgifera LeConte is a major pest of corn causing millions of dollars of economic loss annually through yield reductions and preventative management practices. Corn producing toxins derived from Bacillus thuringiensis (Bt) have been developed to help manage D. v. virgifera. Sinc...

  3. [Corn.

    ERIC Educational Resources Information Center

    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,…

  4. Characterization of a new bacteriocin from Lactobacillus plantarum LE5 and LE27 isolated from ensiled corn.

    PubMed

    Amortegui, Jairo; Rodríguez-López, Alexander; Rodríguez, Deicy; Carrascal, Ana K; Alméciga-Díaz, Carlos J; Melendez, Adelina del P; Sánchez, Oscar F

    2014-04-01

    Bacteriocins are low molecular peptides with antimicrobial activity, which are of great interest as food bio-preservatives and for treating diseases caused by pathogenic bacteria. In this study, we present the characterization of bacteriocins produced by Lactobacillus plantarum LE5 and LE27 isolated from ensiled corn. Bacteriocins were purified through ammonium sulfate precipitation and double dialysis by using 12- and 1-kDa membranes. Bacteriocins showed activity against Listeria innocua, Listeria monocytogenes, and Enteroccocus faecalis. Molecular weight was estimated through Tricine-SDS-PAGE and overloading the gel onto Mueller-Hinton agar seeded with L. monocytogenes, showing an inhibition zone between 5 and 10 kDa. NanoLC-MS/MS analysis allowed the identification of UPF0291 protein (UniProtKB/Swiss-Prot Q88VI7), which is also presented in other lactic acid bacteria without assigned function. Ab initio modeling showed it has an α-helix-rich structure and a large positive-charged region. Bacteriocins were stable between 4 and 121 °C and pH 2 and 12, and the activity was inhibited by SDS and proteases. Mode of action assay suggests that the bacteriocin causes of target microorganism. Taken together, these results describe a possible new class IIa bacteriocin produced by L. plantarum, which has a wide stability to physicochemical conditions, and that could be used as an alternative for the control of foodborne diseases. PMID:24532444

  5. Corn

    MedlinePlus

    ... composed of a dense core that presses on sensory nerves, causing extreme pain. Soft corns occur between ... a benign condition and may not require medical evaluation. However, if corns become very painful, evaluation should ...

  6. Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) Population Dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Much has been learned about the population dynamics of the western corn rootworm over the last half-century of intensive study, and this knowledge has helped humans manage this destructive pest of corn relatively successfully. However, this insect is something of a moving target when it comes to un...

  7. Binary toxins from Bacillus thuringiensis active against the western corn rootworm, Diabrotica virgifera virgifera LeConte.

    PubMed

    Baum, James A; Chu, Chi-Rei; Rupar, Mark; Brown, Gregory R; Donovan, William P; Huesing, Joseph E; Ilagan, Oliver; Malvar, Thomas M; Pleau, Michael; Walters, Matthew; Vaughn, Ty

    2004-08-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is a significant pest of corn in the United States. The development of transgenic corn hybrids resistant to rootworm feeding damage depends on the identification of genes encoding insecticidal proteins toxic to rootworm larvae. In this study, a bioassay screen was used to identify several isolates of the bacterium Bacillus thuringiensis active against rootworm. These bacterial isolates each produce distinct crystal proteins with approximate molecular masses of 13 to 15 kDa and 44 kDa. Insect bioassays demonstrated that both protein classes are required for insecticidal activity against this rootworm species. The genes encoding these proteins are organized in apparent operons and are associated with other genes encoding crystal proteins of unknown function. The antirootworm proteins produced by B. thuringiensis strains EG5899 and EG9444 closely resemble previously described crystal proteins of the Cry34A and Cry35A classes. The antirootworm proteins produced by strain EG4851, designated Cry34Ba1 and Cry35Ba1, represent a new binary toxin. Genes encoding these proteins could become an important component of a sustainable resistance management strategy against this insect pest. PMID:15294828

  8. Binary Toxins from Bacillus thuringiensis Active against the Western Corn Rootworm, Diabrotica virgifera virgifera LeConte

    PubMed Central

    Baum, James A.; Chu, Chi-Rei; Rupar, Mark; Brown, Gregory R.; Donovan, William P.; Huesing, Joseph E.; Ilagan, Oliver; Malvar, Thomas M.; Pleau, Michael; Walters, Matthew; Vaughn, Ty

    2004-01-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is a significant pest of corn in the United States. The development of transgenic corn hybrids resistant to rootworm feeding damage depends on the identification of genes encoding insecticidal proteins toxic to rootworm larvae. In this study, a bioassay screen was used to identify several isolates of the bacterium Bacillus thuringiensis active against rootworm. These bacterial isolates each produce distinct crystal proteins with approximate molecular masses of 13 to 15 kDa and 44 kDa. Insect bioassays demonstrated that both protein classes are required for insecticidal activity against this rootworm species. The genes encoding these proteins are organized in apparent operons and are associated with other genes encoding crystal proteins of unknown function. The antirootworm proteins produced by B. thuringiensis strains EG5899 and EG9444 closely resemble previously described crystal proteins of the Cry34A and Cry35A classes. The antirootworm proteins produced by strain EG4851, designated Cry34Ba1 and Cry35Ba1, represent a new binary toxin. Genes encoding these proteins could become an important component of a sustainable resistance management strategy against this insect pest. PMID:15294828

  9. Behavior and Ecology of the Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. Western corn rootworm beetles (WCR) are historic pests with a legacy of resistance and behavioral plasticity. Current patterns of behavior and nutritional ecology are important and relevant to the history and the future of rootworm management. The success of the most effective and environmenta...

  10. Ultrastructural changes caused by Snf7 RNAi in larval enterocytes of western corn rootworm (Diabrotica virgifera virgifera Le Conte).

    PubMed

    Koči, Juraj; Ramaseshadri, Parthasarathy; Bolognesi, Renata; Segers, Gerrit; Flannagan, Ronald; Park, Yoonseong

    2014-01-01

    The high sensitivity to oral RNA interference (RNAi) of western corn rootworm (WCR, Diabrotica virgifera virgifera Le Conte) provides a novel tool for pest control. Previous studies have shown that RNAi of DvSnf7, an essential cellular component of endosomal sorting complex required for transport (ESCRT), caused deficiencies in protein de-ubiquitination and autophagy, leading to WCR death. Here we investigated the detailed mechanism leading to larval death by analyzing the ultrastructural changes in midgut enterocytes of WCR treated with double-stranded RNA (ds-DvSnf7). The progressive phases of pathological symptoms caused by DvSnf7-RNAi in enterocytes include: 1) the appearance of irregularly shaped macroautophagic complexes consisting of relatively large lysosomes and multi-lamellar bodies, indicative of failure in autolysosome formation; 2) cell sloughing and loss of apical microvilli, and eventually, 3) massive loss of cellular contents indicating loss of membrane integrity. These data suggest that the critical functions of Snf7 in insect midgut cells demonstrated by the ultrastructural changes in DvSnf7 larval enterocytes underlies the conserved essential function of the ESCRT pathway in autophagy and membrane stability in other organisms. PMID:24409288

  11. Identification of sensilla involved in taste mediation in adult western corn rootworm (Diabrotica virgifera virgifera LeConte).

    PubMed

    Chyb, S; Eichenseer, H; Hollister, B; Mullin, C A; Frazier, J L

    1995-03-01

    A group of sensilla present on the maxillary galea of adult western corn rootworm,Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) beetles has been identified morphologically and physiologically to be involved in taste mediation. There are approximately 15 chemosensory hairs on each galea. Bilateral removal of these structures resulted in a significantly reduced consumption of a strongly phagostimulant triterpenoid, cucurbitacin B, and led to increased ingestion of a phagodeterrent alkaloid, strychnine. Electrophysiological responses obtained via tip-recording of galeal chemosensilla with submillimolar concentrations of host and nonhost plant compounds resulted in dose responses overlapping with the effective behavioral ranges. Cucurbitacin B was found to evoke chemosensory responses at levels as low as 0.1µM. Sinceγ-aminobutyric acid (GABA) is an agonist. (-)-β-hydrastine and strychnine are antagonists, and cucurbitacin B has been proposed to act at a separate modulatory site of classical synaptic GABA and glycine receptor-channel complexes, results reported here raise the possibility that there are peripheral chemosensory receptor sites that may resemble, functionally and structurally, synaptic receptor sites in the central nervous system. PMID:24234063

  12. Screening for corn rootworm (Coleoptera: Chrysomelidae) resistance to transgenic Bt corn in North Dakota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western (WCR), Diabrotica virgifera virgifera LeConte, and northern corn rootworms (NCR), D. barberi Smith & Lawrence, are major economic pests of corn in much of the U.S. Corn Belt. Western corn rootworm resistance to transgenic corn expressing Bt (Bacillus thuringiensis) endotoxins has been confi...

  13. Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) Populations in Western Nebraska and Kansas.

    PubMed

    Pereira, Adriano E; Wang, Haichuan; Zukoff, Sarah N; Meinke, Lance J; French, B Wade; Siegfried, Blair D

    2015-01-01

    Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99) was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial). For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99) were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed. PMID:26566127

  14. Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) Populations in Western Nebraska and Kansas

    PubMed Central

    Pereira, Adriano E.; Wang, Haichuan; Zukoff, Sarah N.; Meinke, Lance J.; French, B. Wade; Siegfried, Blair D.

    2015-01-01

    Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99) was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial). For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99) were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed. PMID:26566127

  15. Parental RNA interference of genes involved in embryonic development of the western corn rootworm, Diabrotica virgifera virgifera LeConte.

    PubMed

    Khajuria, Chitvan; Vélez, Ana M; Rangasamy, Murugesan; Wang, Haichuan; Fishilevich, Elane; Frey, Meghan L F; Carneiro, Newton Portilho; Gandra, Premchand; Narva, Kenneth E; Siegfried, Blair D

    2015-08-01

    RNA interference (RNAi) is being developed as a potential tool for insect pest management and one of the most likely target pest species for transgenic plants that express double stranded RNA (dsRNA) is the western corn rootworm. Thus far, most genes proposed as targets for RNAi in rootworm cause lethality in the larval stage. In this study, we describe RNAi-mediated knockdown of two developmental genes, hunchback (hb) and brahma (brm), in the western corn rootworm delivered via dsRNA fed to adult females. dsRNA feeding caused a significant decrease in hb and brm transcripts in the adult females. Although total oviposition was not significantly affected, there was almost complete absence of hatching in the eggs collected from females exposed to dsRNA for either gene. These results confirm that RNAi is systemic in nature for western corn rootworms. These results also indicate that hunchback and brahma play important roles in rootworm embryonic development and could provide useful RNAi targets in adult rootworms to prevent crop injury by impacting the population of larval progeny of exposed adults. The ability to deliver dsRNA in a trans-generational manner by feeding to adult rootworms may offer an additional approach to utilizing RNAi for rootworm pest management. The potential to develop parental RNAi technology targeting progeny of adult rootworms in combination with Bt proteins or dsRNA lethal to larvae may increase opportunities to develop sustainable approaches to rootworm management involving RNAi technologies for rootworm control. PMID:26005118

  16. Performance of a model for egg hatching of the western corn rootworm, Diabrotica virgifera virgifera LeConte, using measured and modelled soil temperatures as input

    NASA Astrophysics Data System (ADS)

    Schaafsma, A. W.; Fuentes, J. D.; Gillespie, T. J.; Whitfield, G. H.; Ellis, C. R.

    1993-03-01

    A model for egg hatching of the western corn rootworm, Diabrotica virgifera virgifera LeConte, was tested at several locations in Ontario, Canada, during the 1989 and 1990 seasons. The model required soil temperatures as input and was tested using measured and modelled data. Modelled soil temperatures at 5 and 10 cm depths were obtained from empirically and physically based models. The physically based model provided better estimates of soil temperatues, but both models slightly underestimated the temperatures. Predicted egg hatching, using measured and modelled soil temperature at 5 and 10 cm depths for all locations, compared reasonably well with the observations of egg hatching. When using modelled soil temperatures, the egg developmental model performed better using soil temperatures from the physically based model. However, both soil temperature models provided sufficiently accurate temperature values for use in the egg developmental model. Unlike the empirically based model, the physically based model was not site-specific and its application to larger areas appeared feasible.

  17. Effect of transgenic corn hybrids and a soil insecticide on corn rootworm (Coleoptera: Chrysomelidae) beetle emergence in North Dakota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Northern, Diabrotica barberi Smith & Lawrence, and western corn rootworms, D. virgifera virgifera LeConte, are economic pests of corn, Zea mays L. (Poaceae) in North Dakota. Many area corn growers rely on transgenic Bt (Bacillus thuringiensis) corn hybrids to manage corn rootworms. Our objective was...

  18. Field-based assessment of resistance to Bt Corn by Western Corn Rootworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a serious pest of corn and is managed with Bt corn that produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt). Beginning in 2009, severe injury to Bt corn producing Cry3Bb1 was observed in some cornfields ...

  19. Novel Bacillus thuringiensis Binary Insecticidal Crystal Proteins Active on Western Corn Rootworm, Diabrotica virgifera virgifera LeConte

    PubMed Central

    Ellis, R. Tracy; Stockhoff, Brian A.; Stamp, Lisa; Schnepf, H. Ernest; Schwab, George E.; Knuth, Mark; Russell, Josh; Cardineau, Guy A.; Narva, Kenneth E.

    2002-01-01

    A new family of insecticidal crystal proteins was discovered by screening sporulated Bacillus thuringiensis cultures for oral activity against western corn rootworm (WCR) larvae. B. thuringiensis isolates PS80JJ1, PS149B1, and PS167H2 have WCR insecticidal activity attributable to parasporal inclusion bodies containing proteins with molecular masses of ca. 14 and 44 kDa. The genes encoding these polypeptides reside in apparent operons, and the 14-kDa protein open reading frame (ORF) precedes the 44-kDa protein ORF. Mutagenesis of either gene in the apparent operons dramatically reduced insecticidal activity of the corresponding recombinant B. thuringiensis strain. Bioassays performed with separately expressed, biochemically purified 14- and 44-kDa polypeptides also demonstrated that both proteins are required for WCR mortality. Sequence comparisons with other known B. thuringiensis insecticidal proteins failed to reveal homology with previously described Cry, Cyt, or Vip proteins. However, there is evidence that the 44-kDa polypeptide and the 41.9- and 51.4-kDa binary dipteran insecticidal proteins from Bacillus sphaericus are evolutionarily related. The 14- and 44-kDa polypeptides from isolates PS80JJ1, PS149B1, and PS167H2 have been designated Cry34Aa1, Cry34Ab1, and Cry34Ac1, respectively, and the 44-kDa polypeptides from these isolates have been designated Cry35Aa1, Cry35Ab1, and Cry35Ac1, respectively. PMID:11872461

  20. Novel Bacillus thuringiensis binary insecticidal crystal proteins active on western corn rootworm, Diabrotica virgifera virgifera LeConte.

    PubMed

    Ellis, R Tracy; Stockhoff, Brian A; Stamp, Lisa; Schnepf, H Ernest; Schwab, George E; Knuth, Mark; Russell, Josh; Cardineau, Guy A; Narva, Kenneth E

    2002-03-01

    A new family of insecticidal crystal proteins was discovered by screening sporulated Bacillus thuringiensis cultures for oral activity against western corn rootworm (WCR) larvae. B. thuringiensis isolates PS80JJ1, PS149B1, and PS167H2 have WCR insecticidal activity attributable to parasporal inclusion bodies containing proteins with molecular masses of ca. 14 and 44 kDa. The genes encoding these polypeptides reside in apparent operons, and the 14-kDa protein open reading frame (ORF) precedes the 44-kDa protein ORF. Mutagenesis of either gene in the apparent operons dramatically reduced insecticidal activity of the corresponding recombinant B. thuringiensis strain. Bioassays performed with separately expressed, biochemically purified 14- and 44-kDa polypeptides also demonstrated that both proteins are required for WCR mortality. Sequence comparisons with other known B. thuringiensis insecticidal proteins failed to reveal homology with previously described Cry, Cyt, or Vip proteins. However, there is evidence that the 44-kDa polypeptide and the 41.9- and 51.4-kDa binary dipteran insecticidal proteins from Bacillus sphaericus are evolutionarily related. The 14- and 44-kDa polypeptides from isolates PS80JJ1, PS149B1, and PS167H2 have been designated Cry34Aa1, Cry34Ab1, and Cry34Ac1, respectively, and the 44-kDa polypeptides from these isolates have been designated Cry35Aa1, Cry35Ab1, and Cry35Ac1, respectively. PMID:11872461

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

    PubMed

    Bolognesi, Renata; Ramaseshadri, Parthasarathy; Anderson, Jerry; Bachman, Pamela; Clinton, William; Flannagan, Ronald; Ilagan, Oliver; Lawrence, Christina; Levine, Steven; Moar, William; Mueller, Geoffrey; Tan, Jianguo; Uffman, Joshua; Wiggins, Elizabeth; Heck, Gregory; Segers, Gerrit

    2012-01-01

    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. PMID:23071820

  2. Characterizing the Mechanism of Action of Double-Stranded RNA Activity against Western Corn Rootworm (Diabrotica virgifera virgifera LeConte)

    PubMed Central

    Bolognesi, Renata; Ramaseshadri, Parthasarathy; Anderson, Jerry; Bachman, Pamela; Clinton, William; Flannagan, Ronald; Ilagan, Oliver; Lawrence, Christina; Levine, Steven; Moar, William; Mueller, Geoffrey; Tan, Jianguo; Uffman, Joshua; Wiggins, Elizabeth; Heck, Gregory; Segers, Gerrit

    2012-01-01

    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. PMID:23071820

  3. Delaying corn rootworm resistance to Bt corn.

    PubMed

    Tabashnik, Bruce E; Gould, Fred

    2012-06-01

    Transgenic crops producing Bacillus thuringiensis (Bt) toxins for insect control have been successful, but their efficacy is reduced when pests evolve resistance. To delay pest resistance to Bt crops, the U.S. Environmental Protection Agency (EPA) has required refuges of host plants that do not produce Bt toxins to promote survival of susceptible pests. Such refuges are expected to be most effective if the Bt plants deliver a dose of toxin high enough to kill nearly all hybrid progeny produced by matings between resistant and susceptible pests. In 2003, the EPA first registered corn, Zea mays L., producing a Bt toxin (Cry3Bb1) that kills western corn rootworm, Diabrotica virgifera virgifera LeConte, one of the most economically important crop pests in the United States. The EPA requires minimum refuges of 20% for Cry3Bb1 corn and 5% for corn producing two Bt toxins active against corn rootworms. We conclude that the current refuge requirements are not adequate, because Bt corn hybrids active against corn rootworms do not meet the high-dose standard, and western corn rootworm has rapidly evolved resistance to Cry3Bb1 corn in the laboratory, greenhouse, and field. Accordingly, we recommend increasing the minimum refuge for Bt corn targeting corn rootworms to 50% for plants producing one toxin active against these pests and to 20% for plants producing two toxins active against these pests. Increasing the minimum refuge percentage can help to delay pest resistance, encourage integrated pest management, and promote more sustainable crop protection. PMID:22812111

  4. Evidence of field-evolved resistance to bifenthrin in western corn rootworm (Diabrotica virgifera virgifera LeConte) populations in western Nebraska and Kansas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyrethroid insecticides are widely used to control larvae or adult western corn rootworm, a key pest of corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to es...

  5. Modelisation et commande des redresseurs triphases fonctionnant a haut rendement et a faible taux de distorsion harmonique: Application au redresseur triphase de vienne

    NASA Astrophysics Data System (ADS)

    Belhadj Youssef, Nesrine

    Les problemes de la qualite de l'onde electrique constituent l'une des preoccupations majeures des fournisseurs de l'energie et des organismes specialises en qualite d'energie. Ce sujet a gagne davantage d'ampleur avec l'utilisation ascendante des convertisseurs de l'energie electrique dans la majorite des applications industrielles et domestiques. Dans le cadre de cette these, on s'interesse plus particulierement au type des convertisseurs alternatif/continu, dont le fonctionnement adequat implique la parfaite regulation du bus DC de tension, l'attenuation des harmoniques de courants, la compensation de l'energie reactive et la maximisation du rendement energetique. Ces differents criteres doivent etre maintenus pour diverses conditions de fonctionnement, c'est-a-dire independamment des variations parametriques auxquelles le systeme peut etre sujet. Il s'avere donc indispensable d'adopter des techniques de commande efficaces, ce qui passe par une modelisation correcte du convertisseur. L'optimisation du nombre de capteurs dans le circuit est egalement un facteur cle a prendre en consideration.

  6. Evidence of resistance to Cry34/35Ab1 corn by western corn rootworm: root injury in the field and larval survival in plant-based bioassays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a serious pest of corn in the United States and recent management of western corn rootworm has included planting of Bt corn. Beginning in 2009, western corn rootworm populations with resistance to Cry3Bb1 c...

  7. Insecticidal proteins from Bacillus thuringiensis protect corn from corn rootworms.

    PubMed

    Moellenbeck, D J; Peters, M L; Bing, J W; Rouse, J R; Higgins, L S; Sims, L; Nevshemal, T; Marshall, L; Ellis, R T; Bystrak, P G; Lang, B A; Stewart, J L; Kouba, K; Sondag, V; Gustafson, V; Nour, K; Xu, D; Swenson, J; Zhang, J; Czapla, T; Schwab, G; Jayne, S; Stockhoff, B A; Narva, K; Schnepf, H E; Stelman, S J; Poutre, C; Koziel, M; Duck, N

    2001-07-01

    Field tests of corn co-expressing two new delta-endotoxins from Bacillus thuringiensis (Bt) have demonstrated protection from root damage by western corn rootworm (Diabrotica virgifera virgifera LeConte). The level of protection exceeds that provided by chemical insecticides. In the bacterium, these proteins form crystals during the sporulation phase of the growth cycle, are encoded by a single operon, and have molecular masses of 14 kDa and 44 kDa. Corn rootworm larvae fed on corn roots expressing the proteins showed histopathological symptoms in the midgut epithelium. PMID:11433280

  8. Localized Search Cues in Corn Roots for Western Corn Rootworm Larvae (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-recognition cues that elicit a unique “tight-turning” behavior by larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte, were extracted from living corn roots with acetone. In behavioral bioassays, an acetone extract of corn roots had activity in the tight-turning bioassa...

  9. Effects of Pyramided Bt Corn and Blended Refuges on Western Corn Rootworm and Northern Corn Rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Keweshan, Ryan S; Head, Graham P; Gassmann, Aaron J

    2015-04-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, and the northern corn rootworm, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae), are major pests of corn (Zea mays L). Several transgenic corn events producing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) kill corn rootworm larvae and reduce injury to corn roots. However, planting of Bt corn imposes selection on rootworm populations to evolve Bt resistance. The refuge strategy and pyramiding of multiple Bt toxins can delay resistance to Bt crops. In this study, we assessed the impact of four treatments--1) non-Bt corn, 2) Cry3Bb1 corn, 3) corn pyramided with Cry3Bb1 and Cry34/35Ab1, and 4) pyramided corn with a blended refuge--on survival, time of adult emergence, and size of western and northern corn rootworm. All treatments with Bt corn led to significant reductions in the number of adults that emerged per plot. However, at one location, we identified Cry3Bb1-resistant western corn rootworm. In some cases Bt treatments reduced size of adults and delayed time of adult emergence, with effects most pronounced for pyramided corn. For both species, the number of adults that emerged from pyramided corn with a blended refuge was significantly lower than expected, based solely on emergence from pure stands of pyramided corn and non-Bt corn. The results of this study indicate that pyramided corn with a blended refuge substantially reduces survival of both western and northern corn rootworm, and as such, should be a useful tool within the context of a broader integrated pest management strategy. PMID:26470183

  10. Knockdown of RNA Interference Pathway Genes in Western Corn Rootworms (Diabrotica virgifera virgifera Le Conte) Demonstrates a Possible Mechanism of Resistance to Lethal dsRNA

    PubMed Central

    Vélez, Ana María; Khajuria, Chitvan; Wang, Haichuan; Narva, Kenneth E.; Siegfried, Blair D.

    2016-01-01

    RNA interference (RNAi) is being developed as a potential tool for insect pest management. Increased understanding of the RNAi pathway in target insect pests will provide information to use this technology effectively and to inform decisions related to resistant management strategies for RNAi based traits. Dicer 2 (Dcr2), an endonuclease responsible for formation of small interfering RNA’s and Argonaute 2 (Ago2), an essential catalytic component of the RNA-induced silencing complex (RISC) have both been associated with the RNAi pathway in a number of different insect species including the western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). We identified both genes from a transcriptome library generated from different tissues and developmental stages of the western corn rootworm, an important target pest for transgenic plants expressing dsRNA targeting essential genes. The expression of these genes was suppressed by more than 90% after injecting gene specific dsRNA into adult rootworms. The injected beetles were then fed vATPase A dsRNA which has previously been demonstrated to cause mortality in western corn rootworm adults. The suppression of both RNAi pathway genes resulted in reduced mortality after subsequent exposure to lethal concentrations of vATPase A dsRNA as well as increased vATPase A expression relative to control treatments. Injections with dsRNA for a non-lethal target sequence (Laccase 2) did not affect mortality or expression caused by vATPase A dsRNA indicating that the results observed with Argo and Dicer dsRNA were not caused by simple competition among different dsRNA’s. These results confirm that both genes play an important role in the RNAi pathway for western corn rootworms and indicate that selection pressures that potentially affect the expression of these genes may provide a basis for future studies to understand potential mechanisms of resistance. PMID:27310918

  11. Isolation and characterization of host recognition cues in corn roots for larvae of the western corn rootworm (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Behavioral bioassays were used to isolate compounds from germinating corn roots that elicit a host recognition response (tight-turning behavior) by neonate larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. When a behaviorally-active extract of germinating corn roots was sep...

  12. CORN FLAVOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn is a large part of the modern diet through sweeteners, oil, processed foods, and animal-derived foods. In addition, corn is eaten directly in bread and cereal-type foods, snack foods, and foods made from masa flour. Corn gluten meal is a byproduct of grain processed by wet milling. Although pri...

  13. Behavioral and electrophysiological dose-response relationships in adult western corn rootworm (Diabrotica virgifera virgifera LeConte) for host pollen amino acids.

    PubMed

    Hollister, Benedict; Mullin, Christopher A.

    1998-05-01

    A strong correlation is shown between taste cell inputs and phagostimulatory outputs with predominant dietary pollen amino acids for western corn rootworm, Diabrotica virgifera virgifera. Behavioral and electrophysiological dose-response profiles in adult beetles are presented for five major free amino acids in host pollens. Differential responses were found with strongest phagostimulation and sensory response elicited by L-alanine and L-serine, followed in order by L-proline and beta-alanine. gamma-Aminobutyric acid gave the weakest and most sporadic response. ED(50) values for phagostimulation and chemosensory input were 28.3nmol/disk and 13mM, respectively, for L-alanine and 17nmol/disk and 11mM, respectively, for serine. Threshold values for the responses were approximately 1-2mM. These behavioral and chemosensory dose-response ranges correspond closely to levels of free amino acids present in host plant pollens. Use of these response values in development of a pollen chemosensory code for western corn rootworm feeding is discussed. PMID:12770166

  14. Susceptibility of Nebraska Western Corn Rootworm (Coleoptera: Chrysomelidae) Populations to Bt Corn Events

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic plants have been widely adopted by growers to manage the western corn rootworm, Diabrotica virgifera virgifera LeConte, in field corn. Because of reduced efficacy in some Nebraska fields after repeated use of Cry3Bb1 expressing hybrids, single plant bioassays were conducted in 2012 and 20...

  15. Corn Insect Pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historically, the major corn insect pests have been corn rootworms (northern and western), European corn borer, and black cutworm. Bt-corn hybrids are effective against most of these pests. However, Bt-corn hybrids are not effective against corn leaf aphid, corn root aphid, sap beetles, corn rootwor...

  16. Corn transformed

    SciTech Connect

    Moffat, A.S.

    1990-08-10

    Researchers have produced fertile corn transformed with a foreign gene that makes the plants resistant to the herbicide bialaphos. This achievement, is the first report of fertile transgenic corn in the reviewed literature, and it is the capstone of almost a decade's efforts to genetically engineer this country's most important crop. The only other major crop to be so manipulated is rice. The ability produce transgenic corn gives biologists a valuable tool to probe the whys and hows of gene expression and regulation. It may also give plant breeders a way to develop new corn varieties with a speed and predictability that would be impossible with classical breeding techniques.

  17. Distribution and antifeedant associations of sesquiterpene lactones in cultivated sunflower (Helianthus annuus L.) on western corn rootworm (Diabrotica virgifera virgifera LeConte).

    PubMed

    Chou, J C; Mullin, C A

    1993-07-01

    Seven antifeedant sesquiterpene lactones (STLs), 4,5-dihydroniveusin A, argophyllin B, argophyllin A, 15-hydroxy-3-dehydrodesoxytifruticin, niveusin B, 1,2-anhydridoniveusin A, and an unidentified epoxide, in cultivated sunflower (Helianthus annuus L.) have been quantified by a highperformance thin-layer chromatography and UV-reflectance scanning densitometry analysis. Age-related expression of STL content in sunflower reveals a heretofore undescribed pattern in which nonpolar STLs such as 15-hydroxy-3-dehydrodesoxytifruticin predominate up to an age of three weeks, but are subsequently displaced by polar STLs, especially argophyllin A, through later foliar stages and anthesis. This leaf pattern of STL ontogeny is maintained in three widely differentH. annuus cultivars (Giant Gray Stripe, Royal Hybrid 2141, Hybrid 7111), which in turn had similar total contents of STLs. Antifeedant activity for western corn rootworm was positively correlated with STL content, particularly with argophyllin A and its isomer argophyllin B, in respective tissue extracts. Enhanced amounts of highly antifeedant argophyllins, especially in newly grown leaf and floral tissues yielding sunflower progeny, strongly suggest that these epoxy-STLs are a chemical defense against insect herbivory. PMID:24249174

  18. Behavioral responses of western corn rootworm larvae to volatile semiochemicals from corn seedlings.

    PubMed

    Hibbard, B E; Bjostad, L B

    1988-06-01

    Corn seedling volatiles collected cryogenically are highly attractive to western corn rootworm larvae,Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), in a laboratory bioassay. Carbon dioxide is known as an attractant for western corn rootworm larvae, and the amount of carbon dioxide in the cryogenic collections was measured with an infrared gas analyzer. In a choice test between a source containing carbon dioxide alone and a source containing corn seedling volatiles with an equal amount of carbon dioxide (verified by infrared gas analysis), western corn rootworm larvae chose the corn volatile source significantly more often than the side with carbon dioxide alone. This indicates that carbon dioxide is only one of the volatiles from corn seedlings that is behaviorally important and that other compounds of behavioral importance are present as well. PMID:24276403

  19. Characterization of the spectrum of insecticidal activity of a double-stranded RNA with targeted activity against Western Corn Rootworm (Diabrotica virgifera virgifera LeConte).

    PubMed

    Bachman, Pamela M; Bolognesi, Renata; Moar, William J; Mueller, Geoffrey M; Paradise, Mark S; Ramaseshadri, Parthasarathy; Tan, Jianguo; Uffman, Joshua P; Warren, Joanne; Wiggins, B Elizabeth; Levine, Steven L

    2013-12-01

    The sequence specificity of the endogenous RNA interference pathway allows targeted suppression of genes essential for insect survival and enables the development of durable and efficacious insecticidal products having a low likelihood to adversely impact non-target organisms. The spectrum of insecticidal activity of a 240 nucleotide (nt) dsRNA targeting the Snf7 ortholog in Western Corn Rootworm (WCR; Diabrotica virgifera virgifera) was characterized by selecting and testing insects based upon their phylogenetic relatedness to WCR. Insect species, representing 10 families and 4 Orders, were evaluated in subchronic or chronic diet bioassays that measured potential lethal and sublethal effects. When a specific species could not be tested in diet bioassays, the ortholog to the WCR Snf7 gene (DvSnf7) was cloned and corresponding dsRNAs were tested against WCR and Colorado potato beetle (Leptinotarsa decemlineata); model systems known to be sensitive to ingested dsRNA. Bioassay results demonstrate that the spectrum of activity for DvSnf7 is narrow and activity is only evident in a subset of beetles within the Galerucinae subfamily of Chrysomelidae (>90% identity with WCR Snf7 240 nt). This approach allowed for evaluating the relationship between minimum shared nt sequence length and activity. A shared sequence length of ≥ 21 nt was required for efficacy against WCR (containing 221 potential 21-nt matches) and all active orthologs contained at least three 21 nt matches. These results also suggest that WCR resistance to DvSnf7 dsRNA due to single nucleotide polymorphisms in the target sequence of 240 nt is highly unlikely. PMID:23748931

  20. Baseline Susceptibility of Western Corn Rootworm (Coleoptera: Chrysomelidae) to Clothianidin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, neonate susceptibility to clothianidin, a highly effective contact and systemic neonicotinoid insecticide, was determined from both laboratory and field collected populations. Neonates were exposed to filter paper treated with increasing...

  1. Blisters, Calluses, and Corns

    MedlinePlus

    ... Help White House Lunch Recipes Blisters, Calluses, and Corns KidsHealth > For Kids > Blisters, Calluses, and Corns Print ... used to all of that stress. What's a Corn? Like calluses, corns are also areas of hard, ...

  2. Corns and calluses

    MedlinePlus

    Calluses and corns ... Corns and calluses are caused by pressure or friction on skin. A corn is thickened skin on the top or side ... the bunion because it rubs against the shoe. Corns and calluses are not serious problems.

  3. Greenhouse-selected resistance to Cry3Bb1-producing corn in three western corn rootworm populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic corn producing the Bacillus thuringiensis (Bt) toxin Cry3Bb1 has been useful for controlling western corn rootworm, Diabrotica virgifera virgifera LeConte, one of the most economically important crop pests in the United States. However, rapid evolution of resistance by this beetle to Bt c...

  4. Selection for resistance to mCry3A-expressing transgenic corn in western corn rootworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To investigate the development of resistance to mCry3A, a laboratory colony of the western corn rootworm, Diabrotica virgifera virgifera LeConte, was established from field survivors of mCry3A-expressing (MIR604) corn. Feral adults emerging from MIR604 (selected) and isoline (control) field plots w...

  5. Corn kernel oil and corn fiber oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unlike most edible plant oils that are obtained directly from oil-rich seeds by either pressing or solvent extraction, corn seeds (kernels) have low levels of oil (4%) and commercial corn oil is obtained from the corn germ (embryo) which is an oil-rich portion of the kernel. Commercial corn oil cou...

  6. Mortality of western corn rootworm larvae on MIR604 transgenic maize roots: field survivorship has no impact on survivorship of F1 progeny on MIR604

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mortality of western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae due to MIR604 transgenic corn (Zea mays L.) expressing the modified Cry3A (mCry3A) protein relative to survivorship on corn with the same genetic background without the gene (isoline corn) was evaluated at three Misso...

  7. Greenhouse-selected resistance to Cry3Bb1-producing corn in three western corn rootworm populations.

    PubMed

    Meihls, Lisa N; Higdon, Matthew L; Ellersieck, Mark R; Tabashnik, Bruce E; Hibbard, Bruce E

    2012-01-01

    Transgenic corn producing the Bacillus thuringiensis (Bt) toxin Cry3Bb1 has been useful for controlling western corn rootworm, Diabrotica virgifera virgifera LeConte, one of the most economically important crop pests in the United States. However, rapid evolution of resistance by this beetle to Bt corn producing Cry3Bb1 has been reported previously from the laboratory, greenhouse, and field. Here we selected in the greenhouse for resistance to Cry3Bb1 corn in three colonies of WCR derived from Kansas, Minnesota, and Wisconsin, respectively. Three generations of rearing on Cry3Bb1 corn significantly increased larval survival on Cry3Bb1 corn, resulting in similar survival in the greenhouse for selected colonies on Cry3Bb1 corn and isoline corn that does not produce Bt toxin. After four to seven generations of rearing on Cry3Bb1 corn, survival in the field on Cry3Bb1 corn relative to isoline corn more than doubled for selected colonies (72%) compared with control colonies (33%). For both selected and control colonies, survival in the field was significantly lower on Cry3Bb1 corn than on isoline corn. On isoline corn, most fitness components were similar for selected colonies and control colonies. However, fecundity was significantly lower for selected colonies than control colonies, indicating a fitness cost associated with resistance. The rapid evolution of resistance by western corn rootworm to Bt corn reported here and previously underlines the importance of effective resistance management for this pest. PMID:23284656

  8. Greenhouse-Selected Resistance to Cry3Bb1-Producing Corn in Three Western Corn Rootworm Populations

    PubMed Central

    Meihls, Lisa N.; Higdon, Matthew L.; Ellersieck, Mark R.; Tabashnik, Bruce E.; Hibbard, Bruce E.

    2012-01-01

    Transgenic corn producing the Bacillus thuringiensis (Bt) toxin Cry3Bb1 has been useful for controlling western corn rootworm, Diabrotica virgifera virgifera LeConte, one of the most economically important crop pests in the United States. However, rapid evolution of resistance by this beetle to Bt corn producing Cry3Bb1 has been reported previously from the laboratory, greenhouse, and field. Here we selected in the greenhouse for resistance to Cry3Bb1 corn in three colonies of WCR derived from Kansas, Minnesota, and Wisconsin, respectively. Three generations of rearing on Cry3Bb1 corn significantly increased larval survival on Cry3Bb1 corn, resulting in similar survival in the greenhouse for selected colonies on Cry3Bb1 corn and isoline corn that does not produce Bt toxin. After four to seven generations of rearing on Cry3Bb1 corn, survival in the field on Cry3Bb1 corn relative to isoline corn more than doubled for selected colonies (72%) compared with control colonies (33%). For both selected and control colonies, survival in the field was significantly lower on Cry3Bb1 corn than on isoline corn. On isoline corn, most fitness components were similar for selected colonies and control colonies. However, fecundity was significantly lower for selected colonies than control colonies, indicating a fitness cost associated with resistance. The rapid evolution of resistance by western corn rootworm to Bt corn reported here and previously underlines the importance of effective resistance management for this pest. PMID:23284656

  9. Implications of corn prices on water footprints of bioethanol.

    PubMed

    Suh, Kyo; Suh, Sangwon; Smith, Timothy

    2011-04-01

    Previously reported water footprints (WFPs) of corn ethanol have been estimated based on the assumption that corn ethanol feedstock could be supplied by the same states where the corn is grown. However, ethanol conversion facilities may choose out-of-state feedstock suppliers depending on the total price of feedstock they have to pay including both the corn price and transportation costs. The purpose of this study is to evaluate the WFPs and total water use (TWU) of corn ethanol considering an optimal allocation of corn with heterogeneous corn feedstock prices across states. The results show that the WFPs of corn ethanol are less than 100 l of water per liter of ethanol (Lw/Le) for all ethanol-producing states based on both the 2008 corn price and transportation costs for rail and truck. Results also reveal that WFPs are very sensitive to the market price of corn and that additional greenhouse gas emissions due to corn trade between states are not significant. PMID:21306890

  10. Evidence of Resistance to Cry34/35Ab1 Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae): Root Injury in the Field and Larval Survival in Plant-Based Bioassays.

    PubMed

    Gassmann, Aaron J; Shrestha, Ram B; Jakka, Siva R K; Dunbar, Mike W; Clifton, Eric H; Paolino, Aubrey R; Ingber, David A; French, B Wade; Masloski, Kenneth E; Dounda, John W; St Clair, Coy R

    2016-08-01

    Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a serious pest of corn in the United States, and recent management of western corn rootworm has included planting of Bt corn. Beginning in 2009, western corn rootworm populations with resistance to Cry3Bb1 corn and mCry3A corn were found in Iowa and elsewhere. To date, western corn rootworm populations have remained susceptible to corn producing Bt toxin Cry34/35Ab1. In this study, we used single-plant bioassays to test field populations of western corn rootworm for resistance to Cry34/35Ab1 corn, Cry3Bb1 corn, and mCry3A corn. Bioassays included nine rootworm populations collected from fields where severe injury to Bt corn had been observed and six control populations that had never been exposed to Bt corn. We found incomplete resistance to Cry34/35Ab1 corn among field populations collected from fields where severe injury to corn producing Cry34/35Ab1, either singly or as a pyramid, had been observed. Additionally, resistance to Cry3Bb1 corn and mCry3A corn was found among the majority of populations tested. These first cases of resistance to Cry34/35Ab1 corn, and the presence of resistance to multiple Bt toxins by western corn rootworm, highlight the potential vulnerability of Bt corn to the evolution of resistance by western corn rootworm. The use of more diversified management practices, in addition to insect resistance management, likely will be essential to sustain the viability of Bt corn for management of western corn rootworm. PMID:27329619

  11. Adult activity and oviposition of corn rootworms, Diabrotica spp. (Coleoptera: Chrysomelidae), in Miscanthus, corn, and switchgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of the biomass crop Miscanthus (Miscanthus × giganteus Greef and Deuter ex Hodkinson and Renvoize) to support larval development for both United States (U.S.) and European populations of the western corn rootworm, Diabrotica virgifera virgifera LeConte, suggests an avenue for potential i...

  12. Adaptation by western corn rootworm to Bt corn: characterizing inheritance, fitness costs, and feeding preference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we used a laboratory-selected, Bt-resistant strain of western corn rootworm, Diabrotica virgifera virgifera Le Conte, to characterize inheritance of resistance, feeding behavior, and fitness costs associated with resistance to maize producing the Bacillus thuringiensis (Bt) toxin Cry3...

  13. Larval mortality and development for rotation-resistant and rotation-susceptible populations of the western corn rootworm on Bt corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is one of the most economically important insect pests threatening the production of corn, Zea mays (L.), in the United States. Throughout its history, this insect has displayed considerable adaptability by overcoming a variety of pe...

  14. Antixenosis in maize reduces feeding by western corn rootworm larvae (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first known example of a naturally-occurring maize genotype with behavioral resistance to western corn rootworm larval feeding was discovered in tests with SUM2162. Behavioral responses of neonate western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae were evaluated in laboratory...

  15. Maize Phenology Affects Establishment, Damage, and Development of the Western Corn Rootworm (Coleoptera:Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of maize (Zea mays L.) phenology on establishment and adult emergence of the western corn rootworm (Diabrotica virgifera virgifera LeConte) as well as plant damage to maize was evaluated in the greenhouse and in field trials in 2001 and 2002. Although neonate western corn rootworm larva...

  16. Inheritance and Fitness Costs of Resistance to Cry3Bb1 Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Ingber, David A; Gassmann, Aaron J

    2015-10-01

    Transgenic crops that produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely planted to manage pest insects. One of the primary pests targeted by Bt corn in the United States is western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae). Cry3Bb1 corn for management of western corn rootworm was commercialized in 2003, and beginning in 2009, populations of western corn rootworm with field-evolved resistance to Cry3Bb1 corn were found in Iowa. Here we quantify the magnitude, inheritance, and fitness costs of resistance to Cry3Bb1 corn in two strains (Hopkinton and Cresco) derived from field populations that evolved resistance to Cry3Bb1 corn. For Hopkinton, we found evidence for complete resistance to Cry3Bb1 corn and nonrecessive inheritance. Additionally, no fitness costs of Cry3Bb1 resistance were detected for Hopkinton. For Cresco, resistance was incomplete and recessive, and we detected fitness costs affecting developmental rate, survival to adulthood, and fecundity. These results suggest that variation may exist among field populations in both the inheritance and accompanying fitness costs of resistance. To the extent that field populations exhibit nonrecessive inheritance and a lack of fitness cost, this will favor more rapid evolution of resistance than would be expected when resistance is functionally recessive and is accompanied by fitness costs. PMID:26453731

  17. Our Mother Corn.

    ERIC Educational Resources Information Center

    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…

  18. Predicting western corn rootworm (Coleoptera: Chrysomelidae) larval injury to rotated corn with Pherocon AM traps in soybeans.

    PubMed

    O'Neal, M E; Gray, M E; Ratcliffe, S; Steffey, K L

    2001-02-01

    Crop rotation for portions of east central Illinois and northern Indiana no longer adequately protects corn (Zea mays L.) roots from western corn rootworm, Diabrotica virgifera virgifera LeConte. Seventeen growers in east central Illinois monitored western corn rootworm adults in soybean (Glycine max L.) fields with unbaited Pherocon AM traps during 1996 and 1997. In the following years (1997 and 1998), growers left untreated strips (no insecticide applied) when these fields were planted with corn. Damage to rotated corn by rootworms was more severe in untreated than in treated strips of rotated corn, ranging from minor root scarring to a full node of roots pruned. Densities of western corn rootworms in soybean fields from 1996 were significantly correlated with root injury to rotated corn the following season. Adult densities from 1997 were not significantly correlated with root injury in 1998, due to heavy precipitation throughout the spring of 1998 and extensive larval mortality. Twenty-eight additional growers volunteered in 1998 to monitor rootworm adults in soybean fields with Pherocon AM traps based on recommendations that resulted from our research efforts in 1996 and 1997. In 1999, these 28 fields were rotated to corn, and rootworm larval injury was measured in untreated strips. Based on 1996-1997 and 1998-1999 data, a regression analysis revealed that 27% of the variation in root injury to rotated corn could be explained by adult density in soybeans the previous season. We propose a sampling plan for soybean fields and a threshold for predicting western corn rootworm larval injury to rotated corn. PMID:11233140

  19. Transgenic approaches to western corn rootworm control.

    PubMed

    Narva, Kenneth E; Siegfried, Blair D; Storer, Nicholas P

    2013-01-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) is a significant corn pest throughout the United States corn belt. Rootworm larvae feed on corn roots causing yield losses and control expenditures that are estimated to exceed US$1 billion annually. Traditional management practices to control rootworms such as chemical insecticides or crop rotation have suffered reduced effectiveness due to the development of physiological and behavioral resistance. Transgenic maize expressing insecticidal proteins are very successful in protecting against rootworm damage and preserving corn yield potential. However, the high rate of grower adoption and early reliance on hybrids expressing a single mode of action and low-dose traits threatens the durability of commercialized transgenic rootworm technology for rootworm control. A summary of current transgenic approaches for rootworm control and the corresponding insect resistance management practices is included. An overview of potential new modes of action based on insecticidal proteins, and especially RNAi targeting mRNA coding for essential insect proteins is provided. PMID:23604211

  20. Modeling the dynamics of adaptation to transgenic corn by western corn rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Onstad, D W; Guse, C A; Spencer, J L; Levine, E; Gray, M E

    2001-04-01

    A simulation model of the population dynamics and genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, was created for a landscape of corn, soybean, and other crops. Although the model was created to study a 2-locus problem for beetles having genes for resistance to both crop rotation and transgenic corn, during this first phase of the project, the model was simulated to evaluate only resistance management plans for transgenic corn. Allele expression in the rootworm and toxin dose in the corn plant were the two most important factors affecting resistance development. A dominant resistance allele allowed quick evolution of resistance to transgenic corn, whereas a recessive allele delayed resistance >99 yr. With high dosages of toxin and additive expression, the time required to reach 3% resistance allele frequency ranged from 13 to >99 yr. With additive expression, lower dosages permitted the resistant allele frequency to reach 3% in 2-9 yr with refuges occupying 5-30% of the land. The results were sensitive to delays in emergence by susceptible adults and configuration of the refuge (row strips versus blocks). PMID:11332850

  1. Evaluation of conventional resistance to European corn borer (Lepidoptera: Crambidae) and western corn rootworm (Coleoptera: Chrysomelidae) in experimental maize lines developed from a backcross breeding program.

    PubMed

    Abel, C A; Berhow, M A; Wilson, R L; Binder, B F; Hibbard, B E

    2000-12-01

    Plant resistance is a promising control method for the two most damaging insect pests of maize, Zea mays L.: the European corn borer, Ostrinia nubilalis (Hübner), and the western corn rootworm Diabrotica virgifera virgifera LeConte. Fifteen experimental lines of maize, derived from a backcross breeding program designed to introgress resistance to European corn borer from Peruvian maize into two U.S. Corn Belt adapted inbred lines, were evaluated for resistance to European corn borer and western corn rootwonrm. The experimental lines were in the second generation of backcrossing. All experimental lines were resistant to leaf blade feeding by European corn borer. These lines had low levels of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one, a chemical commonly associated with leaf blade feeding resistance, indicating that this was not the mechanism of resistance to leaf blade feeding in these lines. Eleven experimental lines were resistant to leaf sheath and collar feeding by European corn borer. Useful sources of European corn borer ovipositional nonpreference and root feeding resistance to western corn rootworm were not identified. Some of the lines evaluated in this study may provide useful sources of resistance to both leaf blade and leaf sheath and collar feeding by European corn borer. PMID:11142317

  2. Post-establishment movement of western corn rootworm larvae (Coleoptera: Chrysomelidae) in Central Missouri corn.

    PubMed

    Hibbard, Bruce E; Duran, Daniel P; Ellersieck, Mark R; Ellsbury, Michael M

    2003-06-01

    If registered, transgenic corn, Zea mays L., with corn rootworm resistance will offer a viable alternative to insecticides for managing Diabrotica spp. corn rootworms. Resistance management to maintain susceptibility is in the interest of growers, the Environmental Protection Agency, and industry, but little is known about many aspects of corn rootworm biology required for an effective resistance management program. The extent of larval movement by the western corn rootworm, Diabrotica virgifera virgifera LeConte, that occurs from plant-to-plant or row-to-row after initial establishment was evaluated in 1998 and 1999 in a Central Missouri cornfield. Post-establishment movement by western corn rootworm larvae was clearly documented in two of four treatment combinations in 1999 where larvae moved up to three plants down the row and across a 0.46-m row. Larvae did not significantly cross a 0.91-m row after initial host establishment in 1998 or 1999, whether or not the soil had been compacted by a tractor and planter. In the current experiment, western corn rootworm larvae moved from highly damaged, infested plants to nearby plants with little to no previous root damage. Our data do not provide significant insight into how larvae might disperse after initial establishment when all plants in an area are heavily damaged or when only moderate damage occurs on an infested plant. A similar situation might also occur if a seed mixture of transgenic and isoline plants were used and if transgenic plants with rootworm resistance are not repellent to corn rootworm larvae. PMID:12852594

  3. Corn rootworms and Bt resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn rootworms have been a major pest of corn for many years. As their name suggests, corn rootworms damage corn plants by feeding on the roots. Western and northern corn rootworms have overcome practices farmers use to keep their population numbers down, such as insecticides and crop rotation. Cor...

  4. Identifying resistance in corn to southwestern corn borer, fall armyworm, and corn earworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Southwestern corn borer, Diatraea grandiosella Dyar; fall armyworm, Spodoptera frugiperda (J.E. Smith); and corn earworm, Helicoverpa zea Boddie, are major insect pests of corn, Zea mays L., in the southern United States. Corn germplasm with resistance to leaf feeding by southwestern corn borer a...

  5. Susceptibility of Nebraska Western Corn Rootworm (Coleoptera: Chrysomelidae) Populations to Bt Corn Events.

    PubMed

    Wangila, David S; Gassmann, Aaron J; Petzold-Maxwell, Jennifer L; French, B Wade; Meinke, Lance J

    2015-04-01

    Transgenic plants have been widely adopted by growers to manage the western corn rootworm, Diabrotica virgifera virgifera LeConte, in field corn. Because of reduced efficacy in some Nebraska fields after repeated use of Cry3Bb1-expressing hybrids, single plant bioassays were conducted in 2012 and 2013 to characterize the susceptibility of western corn rootworm populations to the rootworm-active proteins Cry3Bb1, mCry3A, and Cry34/35Ab1. Results demonstrate that there are heritable differences in susceptibility of Nebraska western corn rootworm populations to rootworm-active Bt traits. Proportional survival and corrected survival data coupled with field histories collectively support the conclusion that a level of field resistance to Cry3Bb1 has evolved in some Nebraska populations in response to selection pressure and that cross-resistance exists between Cry3Bb1 and mCry3A. There was no apparent cross-resistance between Cry34/35Ab1 and either Cry3Bb1 or mCry3A. The potential implications of these results on current and future corn rootworm management strategies are discussed. PMID:26470186

  6. The effect of western corn rootworm (Coleoptera: Chrysomelidae) and water deficit on maize performance under controlled conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of greenhouse experiments using three infestation levels of the western corn rootworm, Diabrotica virgifera virgifera LeConte, under well-watered, moderately dry, and very dry soil moisture levels were conducted to quantify the interaction of western corn rootworm and soil water deficit on ...

  7. A Western Corn Rootworm Cadherin-like Protein is not Involved in the Binding and Toxicity of Cry34/35Ab1 and Cry3Aa Bacillus Thuringiensis Proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm (WCR) Diabrotica virgifera virgifera LeConte is an important insect pest of corn. Bacillus thuringiensis (Bt) insecticidal proteins Cry3Aa (as mCry3A) and Cry34Ab1/Cry35Ab1 have been expressed in transgenic corn and are used to control the insect in the U.S. To date, there ...

  8. PRODUCING HIGH CORN YIELDS.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Coll. of Agriculture.

    RESOURCE MATERIAL ON CORN PRODUCTION FOR HIGH SCHOOL VOCATIONAL AGRICULTURE AND ADULT FARMER CLASSES WAS DESIGNED BY A STATE LEVEL GROUP OF SUBJECT MATTER SPECIALISTS, TEACHER EDUCATORS, SUPERVISORS, AND TEACHERS TO HELP SOLVE PROBLEMS THAT CONFRONT CORN PRODUCERS AT PLANTING TIME. THE SUBJECT MATTER CONCERNS PLANTING TIME, DEPTH, ROW WIDTH,…

  9. Corn blight watch experiment

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The corn blight problem is briefly described how the experiment was organized and conducted, the effect of the blight on the 1971 crop, and some conclusions that may be drawn as a result of the experiment. The information is based on preliminary reports of the Corn Blight Watch Steering Committee and incorporates much illustrative material conceived at Purdue University.

  10. A novel Bacillus thuringiensis (PS149B1) containing a Cry34Ab1/Cry35Ab1 binary toxin specific for the western corn rootworm Diabrotica virgifera virgifera LeConte forms ion channels in lipid membranes.

    PubMed

    Masson, Luke; Schwab, George; Mazza, Alberto; Brousseau, Roland; Potvin, Lena; Schwartz, Jean-Louis

    2004-09-28

    The binary Bacillus thuringiensis PS149B1 insecticidal crystal (Cry) protein is comprised of two components, Cry34Ab1, a 14-kDa protein, and Cry35Ab1, a 44-kDa protein, the combination of which forms a novel binary toxin active on western corn rootworm larvae. The permeabilizing behavior of the native binary toxin and its two individual components expressed as recombinant proteins was studied using calcein efflux determination in liposomes and by ion channel activity measurements in planar lipid bilayers (PLBs). Data obtained with solubilized native PS149B1 binary protein revealed it to be a pore-forming toxin that can permeabilize liposomes and form ion channels ( approximately 300-900 pS) in PLBs at pH 5.5 but not pH 9.0. The 14-kDa component of the toxin also formed ion channels ( approximately 15-300 pS) at pH 5.5 but did not insert easily in PLBs. While the 44-kDa moiety did seldomly form resolvable ion channels ( approximately 15-750 pS) in PLBs, it did destabilize the membranes. It showed pH-dependent truncation to a stable 40-kDa protein. The purified 40-kDa truncated product formed channels ( approximately 10-450 pS) in PLBs at pH 5.5. At that same pH, while a 3:1 molar mixture (14:44 kDa) of the individual components of the toxin induced channel activity that resembled that of the 14-kDa component alone, the 3:1 molar mixture of the 14-kDa component and 40-kDa truncated product induced channel activity ( approximately 20-800 pS) similar to that of PS149B1 in planar lipid bilayers. We conclude that the overall membrane permeabilization process of Cry34Ab1/Cry35Ab1 is a result of ion channel formation. PMID:15379574

  11. Le Rendement en Lecture dans les Ecoles Franco-Ontariennes (Sixieme, Septieme, et Huitieme Annees) (Reading in Franco-Ontarian Schools [Sixth, Seventh, and Eighth Grades]).

    ERIC Educational Resources Information Center

    Brassard, Jean; Langevin, Claude

    A research project was carried out to investigate the reading situation in the sixth, seventh, and eighth grades of French-language schools in Ontario. Specifically, the project sought to determine the nature of reading deficiencies found in these schools, the percentage of the student body affected by these deficiencies, and the psychological,…

  12. Kepler Corn Maze

    NASA Video Gallery

    The Dell'Osso Family Farm, located on the outskirts of Lathrop, California held the grand opening of their corn maze that was designed with a NASA theme. The maze is part of a nation-wide group of ...

  13. TQM at Corning.

    PubMed

    Houghton, J

    1992-01-01

    Houghton has been with Corning for 30 years, up through the ranks. Now, as chairman and CEO, his individual leadership stamp is TQM. It's a major turn-around story with Total Quality at its center. PMID:10117839

  14. Argentina corn yield model

    NASA Technical Reports Server (NTRS)

    Callis, S. L.; Sakamoto, C.

    1984-01-01

    A model based on multiple regression was developed to estimate corn yields for the country of Argentina. A meteorological data set was obtained for the country by averaging data for stations within the corn-growing area. Predictor variables for the model were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature. A trend variable was included for the years 1965 to 1980 since an increasing trend in yields due to technology was observed between these years.

  15. Energy balance and turbulent flux partitioning in a corn-soybean rotation in the Midwestern US

    NASA Astrophysics Data System (ADS)

    Hernandez-Ramirez, Guillermo; Hatfield, Jerry L.; Prueger, John H.; Sauer, Thomas J.

    2010-03-01

    Quantifying the energy balance above plant canopies is critical for better understanding of water balance and changes in regional weather patterns. This study examined temporal variations of energy balance terms for contrasting canopies [corn ( Zea mays L.) and soybean ( Glycine max L. Merr.)]. We monitored energy balance for 4 years using eddy-covariance systems, net radiometers, and soil heat flux plates in adjacent production fields near Ames, Iowa. On an annual basis, soybean exhibited 20% and 30% lower sensible heat flux ( H) and Bowen ratio than corn, respectively. As canopies developed, a gradual shift in turbulent fluxes occurred with decreasing H and increasing latent heat flux (LE), but with a more pronounced effect for corn. Conversely, during mid-growing season and as both canopies progressively senesced, H in general increased and LE decreased; however, soybean exhibited slightly greater LE and much lower H than corn. These temporal variations in magnitude and partitioning of turbulent fluxes translated into a pronounced energy imbalance for soybean (0.80) and an enhanced closure for corn (0.98) in August and September. These discrepancies could be directly associated with differences in momentum transport as shown by friction velocities of 0.34 and 0.28 m s-1 for corn and soybean, respectively. These results support influential roles of plant canopy on intensity and mode of surface energy exchange processes.

  16. 21 CFR 184.1321 - Corn gluten.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... glutelin. Corn gluten is a byproduct of the wet milling of corn for starch. The gluten fraction is washed... conversion of the starch in whole or various fractions of dry milled corn to corn syrups. (b) The...

  17. 21 CFR 184.1321 - Corn gluten.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... glutelin. Corn gluten is a byproduct of the wet milling of corn for starch. The gluten fraction is washed... conversion of the starch in whole or various fractions of dry milled corn to corn syrups. (b) The...

  18. 21 CFR 184.1321 - Corn gluten.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... glutelin. Corn gluten is a byproduct of the wet milling of corn for starch. The gluten fraction is washed... conversion of the starch in whole or various fractions of dry milled corn to corn syrups. (b) The...

  19. 21 CFR 184.1321 - Corn gluten.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... glutelin. Corn gluten is a byproduct of the wet milling of corn for starch. The gluten fraction is washed... conversion of the starch in whole or various fractions of dry milled corn to corn syrups. (b) The...

  20. Multiplex polymerase chain reaction method for differentiating western and northern corn rootworm larvae (Coleoptera: Chrysomelidae).

    PubMed

    Roehrdanz, Richard L

    2003-06-01

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, and northern corn rootworm, D. barberi Smith and Lawrence, are sympatric species and serious pests of corn cultivation in North America. Comparison of nucleotide sequence of mitochondrial cytochrome oxidase I and II was used to design polymerase chain reaction (PCR) primers that discriminate immature stages of the two species based on differences in amplicon size. Multiplex PCR can be used to give a positive test for each species in a single amplification reaction. This provides a method to identify field caught larvae and facilitates investigations of larval interaction and competition between the species. PMID:12852603

  1. Carbon isotope ratios document that the elytra of western corn rootworm reflects adult versus larval feeding and later instar larvae prefer Bt corn to alternate hosts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is a major pest of maize, Zea mays L., worldwide. While exploring conventional approaches to management and more recently bioengineering, extended research has been conducted on ways to manage its root-feeding larvae. The nee...

  2. Density-Dependent and Density-Independent Mortality of the Western Corn Rootworm: Impact on Dose Calculations of Rootworm-Resistant Bt Corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The percent of viable eggs of the western corn rootworm, Diabrotica virgifera virgifera LeConte, which survived to the adult stage was evaluated for the effect of egg density in 2005 and 2007 in Central Missouri. In 2005, each plot was 2.44 m × 3.05 m and contained 64 maize, Zea mays L., plants. I...

  3. Impact of western corn rootworm (Coleoptera: Chrysomelidae) on sweet corn and evaluation of insecticidal and cultural control options.

    PubMed

    Hoffmann, M P; Kirkwyland, J J; Gardner, J

    2000-06-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is an important pest of corn, Zea mays L., causing yield losses from root damage, plant lodging, and silk feeding. Because little is known about its impact on sweet corn, we conducted research to evaluate the combined effects of insecticide, planting date, and cultivar on root damage, plant lodging, and yield in central New York sweet corn. We also examined the influence of planting date and cultivar on the emergence of adult western corn rootworms. The research was conducted in 1994 and again in 1995 by using a split-split plot experimental design with insecticide as main plot, planting date as subplot, and cultivar as sub-subplot. The effect of cultivar on beetle emergence was not significant. Root damage was not correlated with adult emergence in 1994 but was positively correlated in 1995. In 1994, there was no interaction of the main factors, and all factors had a significant impact on root damage. In 1995 there was an interaction of insecticide and planting date, and of cultivar and planting date. Generally, root damage was reduced by insecticide and later planting. Plant lodging was affected by the interaction of insecticide and planting date, and the interaction of cultivar and planting date, for both years of the study. As with root damage, lodging was reduced with insecticide treatment and later planting but also was dependent on cultivar. In 1994 and especially in 1995, silk clipping by adult western corn rootworms precluded much inference about how yield was influenced by larval feeding damage on roots. The number of emerging western corn rootworm adults was lower and later in later plantings. PMID:10902334

  4. Foliar diseases of corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf blights and spots caused by fungi are some of the most destructive diseases of corn in the US and around the world. Correct identification of the disease is very important in determining the best means of control. For example, gray leaf spot of maize can be caused by one of at least two species...

  5. Indiana Corn Dry Mill

    SciTech Connect

    2006-09-01

    The goal of this project is to perform engineering, project design, and permitting for the creation and commercial demonstration of a corn dry mill biorefinery that will produce fuel-grade ethanol, distillers dry grain for animal feed, and carbon dioxide for industrial use.

  6. Examining cuphea as a potential host for western corn rootworm (Coleoptera: Chrysomelidae): larval development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In previous crop rotation research, adult emergence traps placed in plots planted to Cuphea PSR-23 (a selected cross of C. viscossisma and C. lanceolata) caught high numbers of adult western corn rootworms, Diabrotica virgifera virgifera LeConte, suggesting that larvae may have completed development...

  7. A core set of microsatellite markers for Western Corn Rootworm (Coleoptera: Chrysomelidae) population genetics studies

    EPA Science Inventory

    Interest in the ecological and population genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, has grown rapidly in the last few years in North America and Europe. This interest is a result of a number of converging issues related to increasing difficult...

  8. Monogalactosyldiacylglycerols as host recognition cues for western corn rootworm larvae (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monogalactosyldiacylglycerol (MGDG) was identified as a host recognition cue for larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. An active glycolipid fraction obtained from an extract of germinating maize roots was isolated with thin layer chromatography using a bioassay-...

  9. Fitness costs of resistance to Cry3Bb1 maize by Western Corn Rootworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crops producing toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely planted to manage insect pests, including western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), a significant pest of maize. The evolution of resistance would diminish the ef...

  10. Mortality impact of MON863 transgenic maize roots on western corn rootworm larvae in the field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mortality of western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae due to feeding on MON863 transgenic maize (Zea mays L.) expressing the Cry3Bb1 protein relative to survivorship on maize with the same genetic background without the gene (isoline maize) was evaluated at three Missour...

  11. Adaptation and Invasiveness of Western Corn Rootworm: Intensifying Research on a Worsening Pest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is an established insect pest of maize (Zea mays L.) in North America. The rotation of maize with another crop, principally soybeans, Glycine max (L.), was the primary management strategy utilized by North American producers and rema...

  12. Toxic and behavioral effects of free fatty acids on western corn rootworm (Coleoptera: Chrysomelidae) larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feeding behavior, feeding intensity and staying behavior of neonate western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae were evaluated in response to synthetic feeding stimulant blends. All of the treatments contained a 3-sugar blend (glucose:fructose:sucrose, 30:4:4 mg per ml) an...

  13. Dynamic precision phenotyping reveals mechanism of crop tolerance to herbivory by the western corn rootworm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm, Diabrotica virgifera virgifera (LeConte) is a major pest of maize, Zea mays L. Over the years, this pest has repeatedly shown its resilience and adaptability not only to traditional crop management strategies including chemical pesticides and crop rotation, but also to de...

  14. LARVAL SAMPLING AND INSTAR DETERMINATION IN FIELD POPULATIONS OF NORTHERN AND WESTERN CORN ROOTWORM (COLEOPTERA: CHRYSOMELIDAE).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head capsule width was measured for northern (Diabrotica barberi Smith & Lawrence) and western corn rootworm (D. virgifera virgifera LeConte) larvae recovered primarily from maize root systems but also from large soil cores each centered around a root system. Larvae for measurement derived from fie...

  15. Methyl anthranilate as a repellent for western corn rootworm larvae (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methyl anthranilate was identified as the active compound in extracts of maize roots that were shown to be repellent to neonate western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae. A bioassay-driven approach was used to isolate the active material from diethyl ether extracts of r...

  16. The Nutritive Value of Dying Maize and Setaria Faberi Roots for Western Corn Rootworm Development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The timing that senescing root tissues of Setaria faberi R.A.W. Herrm. and maize, Zea mays L., no longer support growth and development of neonate and 2nd instar western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae was evaluated under greenhouse conditions. Three separate experimen...

  17. Environmental and Genotypic Effects for Western Corn Rootworm Tolerance Traits in American and European Maize Trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm (Diabrotica virgifera virgifera LeConte) (WCR) is the most destructive pest of maize in North America currently causing considerable economic losses also in Central and Southeast Europe. Developing and releasing of commercial hybrids with higher level of native (host-plant)...

  18. Development and characterization of MIR604 resistance in a western corn rootworm population (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    mCry3A is one of only four proteins licensed for commercial use in Diabrotica control. Utilizing a colony of western corn rootworm, Diabrotica virgifera virgifera LeConte, selected for resistance to mCry3A, we evaluated how mCry3A resistance was inherited and whether fitness costs were associated wi...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  20. Impact of the Bt corn proteins Cry34/35Ab1 and Cry3Bb1, alone or pyramided, on western corn rootworm (Coleoptera: Chrysomelidae) beetle emergence in the field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major pest of corn, Zea mays L. This study compared the effect of the Bt proteins Cry34/35Ab1, Cry3Bb1, singly expressed, and Cry3Bb1 plus Cry34/35Ab1 in a pyramid, with a near-isoline control, on D. virgifera adult emergence in fie...

  1. 21 CFR 184.1262 - Corn silk and corn silk extract.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Corn silk and corn silk extract. 184.1262 Section... Affirmed as GRAS § 184.1262 Corn silk and corn silk extract. (a) Corn silk is the fresh styles and stigmas of Zea mays L. collected when the corn is in milk. The filaments are extracted with dilute ethanol...

  2. Callosities, corns, and calluses.

    PubMed Central

    Singh, D.; Bentley, G.; Trevino, S. G.

    1996-01-01

    Inappropriate shoes, abnormal foot mechanics, and high levels of activity produce pressure and friction that lead to corns and calluses. Most lesions can be managed conservatively by proper footwear, orthoses, and, if necessary, regular paring. The lesions usually disappear when the causative mechanical forces are removed. Surgery is rarely indicated and should be specifically aimed at correcting the abnormal mechanical stresses. Images Fig 2 Fig 3 Fig 4 Fig 6 Fig 7 PMID:8646101

  3. Identification of a female-produced sex pheromone of the western corn rootworm.

    PubMed

    Guss, P L; Tumlinson, J H; Sonnet, P E; Proveaux, A T

    1982-02-01

    A sex pheromone has been isolated and identified from virgin females of the western corn rootworm (WCR),Diabrotica virgifera virgifera LeConte. The synthesized compound, racemic 8-methyl-2-decanol propanoate, was equal in attraction to the natural pheromone when tested in the field as a trap bait against three taxa ofDiabrotica known to respond to pheromone extracts from female WCR. Five taxa (D. virgifera virgifera; D. virgifera zeae Krysan and Smith, Mexican corn rootworm;D. longicornis barberi Smith and Lawrence, northern corn rootworm;D. longicornis longicornis (Say); andD. porracea Harold) were attracted to traps baited with 8-methyl-2-decanol propanoate. The response of male northern corn rootworms (NCR) in the field peaked at a relatively low concentration of 8-methyl-2-decanol propanoate and then was severely reduced at the higher concentrations tested. Conversely, the response of male WCR in the field continued to increase up to the highest dose tested. PMID:24414965

  4. 21 CFR 184.1321 - Corn gluten.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... principal protein component of corn endosperm. It consists mainly of zein and glutelin. Corn gluten is a... soluble proteins. Corn gluten is also produced as a byproduct during the conversion of the starch in...

  5. Ovarian development and ovipositional preference of the western corn rootworm (Coleoptera: Chrysomelidae) variant in east central Illinois.

    PubMed

    Rondon, Silvia I; Gray, Michael E

    2004-04-01

    The rotation of maize, Zea mays L., and soybean, Glycine max (L.) Merr., has been the traditional cultural tactic to manage the western corn rootworm, Diabrotica virgifera virgifera LeConte, in the Corn Belt. The reduced effectiveness of this rotation as a pest management tool in east central Illinois, northern Indiana, and southern Michigan can be explained by the shift in the ovipositional behavior of the new variant of western corn rootworm. The objective of this study was to evaluate the influence of maize, soybean, oat, Avena sativa L., stubble, and alfalfa, Medicago sativa L., on the ovarian development and ovipositional preferences of the variant western corn rootworm. Field research was conducted near Urbana, IL, during 1998-2000. Gravid females were present throughout the season in all crops, and due to the prolonged period in which western corn rootworm females can lay eggs, none of the crops were immune from oviposition. Results indicated that the western corn rootworm variant oviposits in maize, soybean, oat stubble, and alfalfa In 1998 and 1999, maize was the preferred oviposition site among crops; however, in 2000, maize, soybean, and oat stubble treatments had similar densities of western corn rootworm eggs. Lack of oviposition preference of the western corn rootworm variant demonstrated in this experiment represents a reasonable explanation of why the effectiveness of the rotation strategy to control western corn rootworm has diminished. PMID:15154460

  6. Management of corn leafhopper (Homoptera: Cicadellidae) and corn stunt disease in sweet corn using reflective mulch.

    PubMed

    Summers, C G; Stapleton, J J

    2002-04-01

    Plastic reflective mulches significantly reduced populations of corn leafhopper, Dalbulus maidis (DeLong & Wolcott), adults and the incidence of corn stunt disease caused by Spiroplasma kunkelii (CSS) in late planted sweet corn (Zea mays L.). The reflective mulches were more effective than were either foliar or soil applied insecticides in managing both the leafhopper and the pathogen it transmits. Yields of marketable ears were 1.5 to 2 times greater in reflective mulch plots than from fallow plots. This was due to larger ears (individual ear weight and length) rather than an increase in the number of ears. The use of reflective mulches provides an alternative strategy to insecticides in the management of both D. maidis and corn stunt disease. Such a strategy may prove useful to growers in Latin America and to limited resource growers and organic growers in the United States who wish to grow corn without the use of insecticides. PMID:12020008

  7. 9 CFR 319.102 - Corned beef round and other corned beef cuts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... beef cuts. 319.102 Section 319.102 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE... Meats, Unsmoked and Smoked § 319.102 Corned beef round and other corned beef cuts. In preparing “Corned Beef Round” and other corned beef cuts, except “Corned Beef Briskets,” the curing solution shall...

  8. 9 CFR 319.102 - Corned beef round and other corned beef cuts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... beef cuts. 319.102 Section 319.102 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE... Meats, Unsmoked and Smoked § 319.102 Corned beef round and other corned beef cuts. In preparing “Corned Beef Round” and other corned beef cuts, except “Corned Beef Briskets,” the curing solution shall...

  9. Aflatoxin in corn hybrids infested at different growth stages with southwestern corn borer (Lepidoptera: Crambidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin is a potent toxin produced by the fungus Aspergillus flavus. Contamination of corn, Zea mays L., with aflatoxin greatly reduces the value of corn grain and is a major impediment to profitable corn production in the South. Infestation of developing corn ears with southwestern corn borer, D...

  10. 21 CFR 184.1865 - Corn syrup.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Corn syrup. 184.1865 Section 184.1865 Food and....1865 Corn syrup. (a) Corn syrup, commonly called “glucose sirup” or “glucose syrup,” is obtained by... dehydrated form (dried glucose sirup). Depending on the degree of hydrolysis, corn syrup may contain,...

  11. Corn Culture: A Story of Intelligent Design

    ERIC Educational Resources Information Center

    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.…

  12. Characterization and Functionality of Corn Germ Proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to evaluate the functional properties of protein extracted from wet-milled corn germ and identify potential applications of the recovered protein. Corn germ comprises 12% of the total weight of normal dent corn and about 29% of the corn protein (moisture-free and oil- free ...

  13. Diapause in northern corn rootworm (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diabroticite corn rootworms are prominent pests of maize and have adapted to both cultural and chemical management methods. In response to a widely used corn-soybean crop rotation in the U.S. Corn Belt over several years, northern corn rootworm (NCR) populations adapted by increasing the proportion ...

  14. Characterization of Corn Grains for Ethanol Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives of this study were to understand how the composition of corn kernels and starch structure affect enzyme hydrolysis of starch in dry-grind corn and ethanol yield from yeast fermentation. Four selected corn inbred lines were used in this study. Starch in uncooked dry-grind corn samples sh...

  15. Responses of northern and western corn rootworms to semiochemical attractants in corn fields.

    PubMed

    Lance, D R

    1988-04-01

    Small plots (18 × 18 m) were treated with grids of cotton wicks that contained semiochemicals for adultDiabrotica barberi Smith and Lawrence, the northern corn rootworm (NCR). In plots treated with eugenol (350 g/hectare), NCR were attracted to point sources of the compound, but there were no significant changes in numbers of either NCR orD. virgifera virgifera LeConte, the western corn rootworm (WCR), found on plants in the plots. In plots treated with 12.5 mg/hectare of 8R-methyl-2R-decyl propanoate (2R,8R-MDP, the apparent female-produced sex pheromone of NCR and WCR), males of both species were attracted to point sources, but beetles did not congregate within treated plots. With racemic 2,8-MDP at 1.0 g/hectare, male WCR were attracted into plots, but NCR of both sexes were strongly repelled. In a separate study, capture of beetles at pheromone-baited traps declined when the surrounding area contained wicks that emitted racemic 2,8-MDP. In treated plots, male WCR were relatively inefficient at finding pheromone sources. With NCR, emigration from plots could account totally for the observed 3- to 10-fold reduction in catch at 0.01-1.0 g/hectare. PMID:24276203

  16. Ethanol extraction of phytosterols from corn fiber

    DOEpatents

    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.

  17. Distribution patterns of MCA-coated granules aerially applied to corn fields of Southern Hungary between 2000 and 2002.

    PubMed

    Wennemann, L; Hummel, H E

    2003-01-01

    Field studies in corn (Zea mays L.) were conducted to evaluate distribution patterns of 4-methoxy-cinnamaldehyde (MCA) coated corn grits after aerial application with a Dromader fixed wing aircraft. The kairomone mimic MCA is synthetically available and a quite specific and efficient adult attractant for the invasive alien maize pest western corn rootworm (WCR) Diabrotica virgifera virgifera LeConte. Orientation disruptive properties of MCA for WCR when applied at unphysiologically high concentrations are currently under investigation. For successful implementation of the MCA disruption technique, the distribution patterns of MCA coated corn granules ('grits') in the field are important. Grits are degrained corn cobs, shredded to different sizes, coated with MCA and used as a carrier material to disseminate MCA vapors into corn fields. Granules of 10-12 mesh size were aerially applied eight times at rates ranging from 12.4 to 25.0 kg/ha. The goal is to evaluate distribution patterns of corn grits treated with MCA in three fields located at Csanadpalota, Kardoskút and Mezöhegyes in Southern Hungary between 2000 and 2002. Increasing rates reflect our attempts in finding and optimising the most even distribution of granules in the field. Field experiments were evaluated by collecting grits in 30-cm plastic saucers and by counting grits accumulated on corn plant parts. Variation in grit number per unit area and frequency of corn granule number per plant showed some transient technical application problems. Analysis of grits collected in the saucers revealed some statistical difference between the different application dates as well as differences in rates applied. Altogether grits in saucers were more evenly distributed in comparison to the grits collected on plant parts. As the corn plants age, their leaves and whorls present a smaller and smaller surface area where granules can accumulate. Altogether, however, grit distribution patterns indicate that aerial

  18. Diagravitropism in corn roots

    NASA Technical Reports Server (NTRS)

    Leopold, A. C.; Wettlaufer, S. H.

    1988-01-01

    The diagravitropic behavior of Merit corn (Zea mays L.) roots grown in darkness provides an opportunity for comparison of two qualitatively different gravitropic systems. As with positive gravitropism, diagravitropism is shown to require the presence of the root cap, have a similar time course for the onset of curvature, and a similar presentation time. In contrast with positive gravitropism, diagravitropism appears to have a more limited requirement for calcium, for it is insensitive to the elution of calcium by EGTA and insensitive to the subsequent addition of a calcium/EGTA complex. These results are interpreted as indicating that whereas the same sensing system is shared by the two types of gravitropism, separate transductive systems are involved, one for diagravitropism, which is relatively independent of calcium, and one for positive gravitropism, which is markedly dependent on calcium.

  19. Grossesse dans une corne rudimentaire: difficultés diagnostiques et prise en charge thérapeutique

    PubMed Central

    Mamouni, Nisrine; Ghazal, Nabil; Erraghay, Sanaa; Bouchikhi, Chahrazed; Banani, Abdelaziz

    2016-01-01

    La survenue d'une grossesse dans une corne utérine rudimentaire est une situation obstétricale extrêmement rare et potentiellement grave, menaçant le pronostic materno-fœtal. Les auteurs rapportent cinq observations de grossesse dans une corne utérine rudimentaire, à travers lesquelles, ils relatent les difficultés sur le plan diagnostique ainsi que la prise en charge thérapeutique de cette entité pathologique, soulignant l'intérêt de l’échographie endovaginale, de l'IRM pelvienne et de la cœlioscopie dans le diagnostic précoce de ce type de malformation uterine.

  20. Carbon isotope ratios document that the elytra of western corn rootworm (Coleoptera: Chrysomelidae) reflects adult versus larval feeding and later instar larvae prefer Bt corn to alternate hosts.

    PubMed

    Hiltpold, Ivan; Adamczyk, John J; Higdon, Matthew L; Clark, Thomas L; Ellersieck, Mark R; Hibbard, Bruce E

    2014-06-01

    In much of the Corn Belt and parts of Europe, the western corn rootworm, Diabrotica virgifera virgifera LeConte, is the most important insect pest of maize. The need for additional basic knowledge of this pest has been highlighted while developing resistance management plans for insecticidal genetically modified crops. This study evaluated the possibility of tracking feeding habits of western corn rootworm larvae using stable carbon isotope signatures. Plants accumulate different ratios of (13)C:(12)C isotopes, usually expressed as δ(13)C, according to whether they use the C3 or C4 photosynthetic pathway. Herbivore biomass is expected to reflect the δ(13)C of the food they eat. For the current experiment, western corn rootworm larvae were grown on different species of plants exhibiting different δ(13)C values. The δ(13)C values were then measured in elytra of emerged beetles. When beetles were unfed, biomass reflected larval feeding. When beetles were fed for 31 d postemergence, δ(13)C values of elytra almost exclusively reflected adult feeding. These results suggest the use of caution in the interpretation of δ(13)C data aiming to document larval diet history when adult feeding history is unknown. The technique was also used to evaluate western corn rootworm larval choice between alternate hosts and maize with and without genetically modified (Bt) traits aimed at their control. Propensity for feeding on alternate hosts versus maize was biased toward feeding on maize regardless whether the maize had Bt or not, suggesting western corn rootworm larvae were not repelled by Bt. These data will be helpful for regulators in interpreting western corn rootworm feeding data on Bt maize. PMID:24874160

  1. Disruption of host location of western corn rootworm larvae (Coleoptera: Chrysomelidae) with carbon dioxide.

    PubMed

    Bernklau, E J; Fromm, E A; Bjostad, L B

    2004-04-01

    Elevated concentrations of carbon dioxide (CO2) prevented neonate larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte, from locating the roots of growing corn in behavioral bioassays conducted in soil tubs. When CO2 was pumped into one end of a soil tub, significantly more larvae were recovered from soil at the treated end than from soil around a growing corn plant at the opposite end of the tub. In controls with ambient air pumped into one end of a soil tub, significantly more larvae were recovered from the soil around the corn plant than from soil on the treated side. Larvae were unable to locate the roots of corn seedlings when CO2-generating materials were mixed into the soil. CO2-concentrations in soil were measured by mass spectrometry with selected ion monitoring at m/z 44. Granules composed of baker's yeast, yeast nutrients, and an organic substrate were prepared as a CO2 source and were tested in larger soil tub bioassays. Significantly fewer larvae were recovered from corn roots in the soil tubs with yeast granules than from corn roots in control soil tubs. The CO2-generating granules produced soil CO2 concentrations between 15.8 and 18.5 mmol/mol (compared with 1.7-2.6 mmol/mol in control tubs), and this was sufficient to prevent larvae from locating corn roots. In field trials, organic and inorganic CO2- generating treatments resulted in root ratings that were significantly lower than for the control plants. PMID:15154452

  2. Diagnostic assays based on esterase-mediated resistance mechanisms in western corn rootworms (Coleoptera: Chrysomelidae).

    PubMed

    Zhou, Xuguo; Scharf, Michael E; Parimi, Srinivas; Meinke, Lance J; Wright, Robert J; Chandler, Laurence D; Siegfried, Blair D

    2002-12-01

    Resistance to methyl-parathion among Nebraska western corn rootworm, Diabrotica virgifera virgifera LeConte, populations is associated with increased hydrolytic metabolism of an organophosphate insecticide substrate. An electrophoretic method to identify resistant individuals based on the staining intensity of esterase isozymes on nondenaturing polyacrylamide gels was developed. Three groups of esterases (I, II, and III) were visible on the gels, but only group II esterase isozymes were intensified in resistant populations. A total of 26 and 31 field populations of western corn rootworms from Nebraska (in 1998 and 1999, respectively) were assessed with nondenaturing polyacrylamide gel electrophoresis (PAGE) assays and diagnostic concentration bioassays. Significant correlations were observed between the two diagnostic assays. Group II esterase isozymes provide a reliable biochemical marker for detection of methyl-parathion resistance in individual western corn rootworms and a tool for monitoring the frequency of resistant individuals in field populations. PMID:12539840

  3. Isolation and characterization of host recognition cues in corn roots for larvae of the western corn rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Bernklau, E J; Hibbard, B E; Bjostad, L B

    2013-12-01

    Behavioral bioassays were used to isolate compounds from germinating corn roots that elicit a host recognition response (tight-turning behavior) by neonate larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. When a behaviorally active extract of germinating corn roots was separated into an aqueous partition and a hexane partition, significantly more larvae (P < 0.05) responded to the recombined partitions than to either partition alone, demonstrating that the active material is a blend comprising both polar and nonpolar compounds. When the aqueous partition was separated with reverse-phase solid phase extraction, most of the behavioral activity was retained in the 100% water fraction (F-1). Gas chromatography-mass spectrometry analysis determined that F-1 contained a blend of small sugars, diacids, amino acids, and inorganic compounds. The nonpolar partition was separated on a silica column, and the resulting fractions were tested in combination with F-1 from the aqueous separation. More than 70% of larvae responded to the 100% acetone fraction (fraction B) in combination with F-1, and the response to this treatment was significantly higher than responses to the other nonpolar fractions or to F-1 alone. Methyl esterification of fraction B, followed by gas chromatographic fatty acid methyl ester analysis, confirmed that fraction B primarily consisted of lipids containing fatty acyl groups. PMID:24498734

  4. Western Corn Rootworm (Coleoptera: Chrysomelidae) Larval Movement in eCry3.1Ab+mCry3A Seed Blend Scenarios.

    PubMed

    Zukoff, Sarah N; Zukoff, Anthony L; Geisert, Ryan W; Hibbard, Bruce E

    2016-08-01

    Corn fields planted with plant-incorporated Bacillus thuringiensis (Bt) proteins must have a portion of the field planted with non-Bt, isoline, plants that serve as a refuge for susceptible insects. In the Corn Belt, refuge seeds are now blended in the bag with Bt seeds for corn hybrids containing two or more toxins targeted toward the western corn rootworm, Diabrotica virgifera virgifera LeConte. Syngenta's corn hybrid, Agrisure Duracade, containing the eCry3.1Ab (event 5307) and mCry3a (event MIR604) rootworm-targeted toxins were registered as a seed blend in 2014. Western corn rootworm larval movement between the refuge plants and the Duracade plants was assessed to determine western corn rootworm survival and amount of root damage on these plants when planted in all possible seed blend scenarios. In this study, western corn rootworm larvae moved between isoline and Bt plants and adult survival was greater on Bt plants if movement from a neighboring infested isoline plant had occurred. However, root damage to these Bt plants did not reach economic levels. The low numbers of western corn rootworm larvae that did move from an infested Bt plant to an isoline plant could potentially select for resistance if they survived to adulthood. PMID:27190042

  5. crw1 - A Novel Maize Mutant Highly Susceptible to Foliar Damage by the Western Corn Rootworm Beetle

    PubMed Central

    Venkata, Bala Puchakayala; Lauter, Nick; Li, Xu; Chapple, Clint; Krupke, Christian; Johal, Gurmukh; Moose, Stephen

    2013-01-01

    Western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is the most destructive insect pest of corn (Zea mays L.) in the United States. The adult WCR beetles derive their nourishment from multiple sources including corn pollen and silks as well as the pollen of alternate hosts. Conversely, the corn foliage is largely neglected as a food source by WCR beetles, leading to a perception of a passive interaction between the two. We report here a novel recessive mutation of corn that was identified and named after its foliar susceptibility to corn rootworm beetles (crw1). The crw1 mutant under field conditions was exceptionally susceptible to foliar damage by WCR beetles in an age-specific manner. It exhibits pleiotropic defects on cell wall biochemistry, morphology of leaf epidermal cells and lower structural integrity via differential accumulation of cell wall bound phenolic acids. These findings indicate that crw1 is perturbed in a pathway that was not previously ascribed to WCR susceptibility, as well as implying the presence of an active mechanism(s) deterring WCR beetles from devouring corn foliage. The discovery and characterization of this mutant provides a unique opportunity for genetic analysis of interactions between maize and adult WCR beetles and identify new strategies to control the spread and invasion of this destructive pest. PMID:23951124

  6. crw1--A novel maize mutant highly susceptible to foliar damage by the western corn rootworm beetle.

    PubMed

    Venkata, Bala Puchakayala; Lauter, Nick; Li, Xu; Chapple, Clint; Krupke, Christian; Johal, Gurmukh; Moose, Stephen

    2013-01-01

    Western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is the most destructive insect pest of corn (Zea mays L.) in the United States. The adult WCR beetles derive their nourishment from multiple sources including corn pollen and silks as well as the pollen of alternate hosts. Conversely, the corn foliage is largely neglected as a food source by WCR beetles, leading to a perception of a passive interaction between the two. We report here a novel recessive mutation of corn that was identified and named after its foliar susceptibility to corn rootworm beetles (crw1). The crw1 mutant under field conditions was exceptionally susceptible to foliar damage by WCR beetles in an age-specific manner. It exhibits pleiotropic defects on cell wall biochemistry, morphology of leaf epidermal cells and lower structural integrity via differential accumulation of cell wall bound phenolic acids. These findings indicate that crw1 is perturbed in a pathway that was not previously ascribed to WCR susceptibility, as well as implying the presence of an active mechanism(s) deterring WCR beetles from devouring corn foliage. The discovery and characterization of this mutant provides a unique opportunity for genetic analysis of interactions between maize and adult WCR beetles and identify new strategies to control the spread and invasion of this destructive pest. PMID:23951124

  7. Emergence and Abundance of Western Corn Rootworm (Coleoptera: Chrysomelidae) in Bt Cornfields With Structured and Seed Blend Refuges.

    PubMed

    Hughson, Sarah A; Spencer, Joseph L

    2015-02-01

    To slow evolution of western corn rootworm (Diabrotica virgifera virgifera LeConte) resistance to Bt (Bacillus thuringiensis Berliner) corn hybrids, non-Bt "refuges" must be planted within or adjacent to Bt cornfields, allowing susceptible insects to develop without exposure to Bt toxins. Bt-susceptible adults from refuges are expected to find and mate with resistant adults that have emerged from Bt corn, reducing the likelihood that Bt-resistant offspring are produced. The spatial and temporal distribution of adults in four refuge treatments (20, 5, and 0% structured refuges and 5% seed blend) and adjacent soybean fields was compared from 2010 to 2012. Adult emergence (adults/trap/day) from refuge corn in structured refuge treatments was greater than that from Bt corn, except during the post-pollination period of corn phenology when emergence from refuge and Bt plants was often the same. Abundance of free-moving adults was greatest in and near refuge rows in structured refuge treatments during vegetative and pollination periods. By post-pollination, adult abundance became evenly distributed. In contrast, adult abundance in 5% seed blends and 0% refuges was evenly distributed, or nearly so, across plots throughout the season. The persistent concentration of adults in refuge rows suggests that structured refuge configurations may not facilitate the expected mixing of adults from refuge and Bt corn. Seed blends produce uniform distributions of adults across the field that may facilitate mating between Bt and refuge adults and ultimately delay the evolution of Bt resistance. PMID:26470111

  8. Patterns of differential gene expression in adult rotation-resistant and wild-type western corn rootworm digestive tracts

    PubMed Central

    Chu, Chia-Ching; Zavala, Jorge A; Spencer, Joseph L; Curzi, Matías J; Fields, Christopher J; Drnevich, Jenny; Siegfried, Blair D; Seufferheld, Manfredo J

    2015-01-01

    The western corn rootworm (WCR,Diabrotica virgifera virgifera LeConte) is an important pest of corn. Annual crop rotation between corn and soybean disrupts the corn-dependent WCR life cycle and is widely adopted to manage this pest. This strategy selected for rotation-resistant (RR) WCR with reduced ovipositional fidelity to corn. Previous studies revealed that RR-WCR adults exhibit greater tolerance of soybean diets, different gut physiology, and host–microbe interactions compared to rotation-susceptible wild types (WT). To identify the genetic mechanisms underlying these phenotypic changes, a de novo assembly of the WCR adult gut transcriptome was constructed and used for RNA-sequencing analyses of RNA libraries from different WCR phenotypes fed with corn or soybean diets. Global gene expression profiles of WT- and RR-WCR were similar when feeding on corn diets, but different when feeding on soybean. Using network-based methods, we identified gene modules transcriptionally correlated with the RR phenotype. Gene ontology enrichment analyses indicated that the functions of these modules were related to metabolic processes, immune responses, biological adhesion, and other functions/processes that appear to correlate to documented traits in RR populations. These results suggest that gut transcriptomic divergence correlated with brief soybean feeding and other physiological traits may exist between RR- and WT-WCR adults. PMID:26240606

  9. The Effect of Western Corn Rootworm (Coleoptera: Chrysomelidae) and Water Deficit on Maize Performance Under Controlled Conditions.

    PubMed

    Mahmoud, M A B; Sharp, R E; Oliver, M J; Finke, D L; Ellersieck, M R; Hibbard, B E

    2016-04-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is the most important insect of maize, Zea mays L., but knowledge of its interaction with water deficit on maize production is lacking. A series of greenhouse experiments using three infestation levels of the western corn rootworm, D. virgifera virgifera, under well-watered, moderately dry, and very dry soil moisture levels were conducted to quantify the interaction of western corn rootworm and soil water deficit on B73×Mo17 maize growth and physiology. Three separate experiments were conducted. Soil moisture regimes were initiated 30 d postplanting for experiments using neonate and second-instar larvae and 30 d postinfestation in the experiment using eggs. In the neonate and second-instar experiments, there were no significant differences among western corn rootworm levels in their effects on leaf water potential, shoot dry weight, and root dry weight. The interaction of western corn rootworm and soil moisture significantly impacted the larval recovery in the neonate experiment, but no other significant interactions were documented between soil moisture levels and rootworm infestation levels. Overall, the results indicate that under the conditions of these experiments, the effect of water deficit was much greater on plants than the effect of western corn rootworm and that the interactions between water deficit and western corn rootworm levels minimally affected the measured parameters of plant performance. PMID:26896532

  10. Patterns of differential gene expression in adult rotation-resistant and wild-type western corn rootworm digestive tracts.

    PubMed

    Chu, Chia-Ching; Zavala, Jorge A; Spencer, Joseph L; Curzi, Matías J; Fields, Christopher J; Drnevich, Jenny; Siegfried, Blair D; Seufferheld, Manfredo J

    2015-08-01

    The western corn rootworm (WCR,Diabrotica virgifera virgifera LeConte) is an important pest of corn. Annual crop rotation between corn and soybean disrupts the corn-dependent WCR life cycle and is widely adopted to manage this pest. This strategy selected for rotation-resistant (RR) WCR with reduced ovipositional fidelity to corn. Previous studies revealed that RR-WCR adults exhibit greater tolerance of soybean diets, different gut physiology, and host-microbe interactions compared to rotation-susceptible wild types (WT). To identify the genetic mechanisms underlying these phenotypic changes, a de novo assembly of the WCR adult gut transcriptome was constructed and used for RNA-sequencing analyses of RNA libraries from different WCR phenotypes fed with corn or soybean diets. Global gene expression profiles of WT- and RR-WCR were similar when feeding on corn diets, but different when feeding on soybean. Using network-based methods, we identified gene modules transcriptionally correlated with the RR phenotype. Gene ontology enrichment analyses indicated that the functions of these modules were related to metabolic processes, immune responses, biological adhesion, and other functions/processes that appear to correlate to documented traits in RR populations. These results suggest that gut transcriptomic divergence correlated with brief soybean feeding and other physiological traits may exist between RR- and WT-WCR adults. PMID:26240606

  11. 21 CFR 155.131 - Canned field corn.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  12. 21 CFR 155.131 - Canned field corn.

    Code of Federal Regulations, 2010 CFR

    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...

  13. 21 CFR 155.131 - Canned field corn.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  14. 21 CFR 155.131 - Canned field corn.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 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...

  15. 21 CFR 155.131 - Canned field corn.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  16. Utilisation of Corn (Zea mays) Bran and Corn Fiber in the Production of Food Components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past decade, the demand for ethanol has increased dramatically. Demand for other products of corn milling, such as starches and sweeteners, is also expected to increase. With the increase in demand for industrial and food use of corn, the production of byproducts, such as corn fiber, corn...

  17. 77 FR 10617 - Wellsboro & Corning Railroad, LLC-Acquisition and Operation Exemption-Wellsboro & Corning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-22

    ... Surface Transportation Board Wellsboro & Corning Railroad, LLC--Acquisition and Operation Exemption--Wellsboro & Corning Railroad Company Wellsboro & Corning Railroad, LLC (WCLLC), a noncarrier, has filed a verified notice of exemption under 49 CFR 1150.31 to acquire from Wellsboro & Corning Railroad Company...

  18. Resistance to Bt corn by western corn rootworm (Coleoptera: Chrysomelidae) in the U.S. corn belt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic Bt corn hybrids that produce insecticidal proteins from the bacterium Bacillus thuringiensis Berliner have become the standard insect management tactic across the United States Corn Belt. Widespread planting of Bt corn creates intense selection pressure for target insects to develop resis...

  19. Corn-in-chip: Mesofluidic Device for Corn Root

    NASA Astrophysics Data System (ADS)

    Kreis, Kevin; Ryu, Sangjin

    2015-03-01

    Plants have a collection of beneficial microorganisms in a region surrounding their roots called the rhizosphere. Although rhizosphere management could increase crop yield, little is known about the interaction between plant roots and their associated microorganisms. Thus we aim to simulate the rhizosphere and monitor root-microbe interactions in the lab environment, and have chosen corn as a model plant because of its economic significance. Here we present our preliminary study to develop a transparent mesofluidic device accommodating the root of corn seedlings into its channel and allowing further growth of the root.

  20. 21 CFR 184.1865 - Corn syrup.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false 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...

  1. 21 CFR 184.1865 - Corn syrup.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false 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...

  2. The 1971 corn blight watch experiment

    NASA Technical Reports Server (NTRS)

    Clifton, J. W.

    1972-01-01

    The successful fulfillment of the objectives for the 1971 corn blight watch experiment is reported. The objectives were: (1) detect the development and spread of corn blight during the growing season across the Corn Belt; (2) assess different levels of infection in the Corn Belt; (3) amplify data acquired by ground observations to better appraise current blight status and the probable impact on crop production; and (4) estimate through extrapolation the applicability of these techniques to similar situations occurring in the future.

  3. Geographic information systems in corn rootworm management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn rootworms (Diabrotica spp. Coleoptera: Chrysomelidae) are serious pests of corn (Zea mays) in the United States and Europe. Control measures for corn rootworms (CRW) were historically based upon chemical pesticides and crop rotation. Pesticide use created environmental and economic concerns. In...

  4. Does Bt Corn Really Produce Tougher Residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  5. 21 CFR 184.1865 - Corn syrup.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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. It may also occur in the dehydrated form (dried glucose sirup). Depending on the degree of...

  6. 21 CFR 184.1865 - Corn syrup.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 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. It may also occur in the dehydrated form (dried glucose sirup). Depending on the degree of...

  7. "King Corn": Teaching the Food Crisis

    ERIC Educational Resources Information Center

    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 industrial…

  8. 9 CFR 319.100 - Corned beef.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... permitting that use in this subchapter or 9 CFR Chapter III, Subchapter E, or in 21 CFR Chapter I, Subchapter... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Corned beef. 319.100 Section 319.100... Corned beef. “Corned Beef” shall be prepared from beef briskets, navels, clods, middle ribs,...

  9. Alfalfa: A Companion Crop with Corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn grain-based ethanol is the major form of biofuel production in the USA. Corn is an attractive biofuel crop because it is easy to manage, process, and ship; is high yielding; and has significant industry support and research. However, there are concerns about growing corn in rotation with soyb...

  10. In-field labeling of western corn rootworm adults (Coleoptera: Chrysomelidae) with rubidium.

    PubMed

    Nowatzki, Timothy M; Niimi, Bradly; Warren, Kelli J; Putnam, Sean; Meinke, Lance J; Gosselin, David C; Harvey, F Edwin; Hunt, Thomas E; Siegfried, Blair D

    2003-12-01

    Field and laboratory studies were conducted in 2000 and 2001 to determine the feasibility of mass marking western corn rootworm adults, Diabrotica virgifera virgifera LeConte, with RbCl in the field. Results showed that application of rubidium (Rb) in solution to both the soil (1 g Rb/plant) and whorl (1 g Rb/plant) of corn plants was optimal for labeling western corn rootworm adults during larval development. Development of larvae on Rb-enriched corn with this technique did not significantly influence adult dry weight or survival. Rb was also highly mobile in the plant. Application of Rb to both the soil and the whorl resulted in median Rb concentrations in the roots (5,860 ppm) that were 150-fold greater than concentrations in untreated roots (38 ppm) 5 wk after treatment. Additionally, at least 90% of the beetles that emerged during the first 3 wk were labeled above the baseline Rb concentration (5 ppm dry weight) determined from untreated beetles. Because emergence was 72% complete at this time, a significant proportion of the population had been labeled. Results from laboratory experiments showed that labeled beetles remained distinguishable from unlabeled beetles for up to 4 d postemergence. The ability to efficiently label large numbers of beetles under field conditions and for a defined period with virtually no disruption of the population provides an unparalleled opportunity to conduct mark-recapture experiments for quantifying the short-range, intrafield movement of adult corn rootworms. PMID:14977112

  11. Effects of replacing conventional corn silage with BMR corn silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. Economics versus alleles: balancing integrated pest management and insect resistance management for rotation-resistant western corn rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Onstad, D W; Crowder, D W; Mitchell, P D; Guse, C A; Spencer, J L; Levine, E; Gray, M E

    2003-12-01

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, has overcome crop rotation in several areas of the central United States. We expanded a simple model of adult behavior and population genetics to explain how rotation resistance may have developed and to study ways to manage the western corn rootworm in a landscape of corn, soybean, and winter wheat where evolution of resistance may occur. We modeled six alternative management strategies over a 15-yr time horizon, as well as a strategy involving a 2-yr rotation of corn and soybean in 85% of the landscape, to investigate their effectiveness from both a biological and economic perspective. Generally, resistance to crop rotation evolves in fewer than 15 yr, and the rate of evolution increases as the level of rotated landscape (selection pressure) increases. When resistance is recessive, all six alternative strategies were effective at preventing evolution of rotation resistance. The two most successful strategies were the use of transgenic rotated corn in a 2-yr rotation and a 3-yr rotation of corn, soybean, and wheat with unattractive wheat (for oviposition) preceding corn. Results were most sensitive to increases in the initial allele frequency and modifications of the density-dependent survival function. Economically, three alternative strategies were robust solutions to the problem, if technology fees were not too high. Repellant soybean, attractive rotated corn, and transgenic rotated corn, all in 2-yr rotations, were economically valuable approaches. However, even the currently common 2-yr rotation was economical when resistance was recessive and the actual costs of resistance would not be paid until far in the future. PMID:14977129

  13. Dispersal behavior of neonate European corn borer (Lepidoptera: Crambidae) on Bt corn.

    PubMed

    Razze, J M; Mason, C E

    2012-08-01

    European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), has historically been a significant economically important insect pest of corn (Zea mays L.) in the United States and Canada. The development in the 1990s of genetically modified corn expressing genes derived from Bacillus thuringiensis (Bt) that encodes insecticidal crystalline (Cry) proteins has proven to be effective in controlling this insect as well as other corn pests. The purpose of this study was to assess the movement and dispersal behavior of neonate European corn borer on Bt corn. We examined differences in neonate European corn borer dispersal behavior for the first 4 h after eclosion in the field among a stacked pyramid (Cry1F X Cry1Ab X Cry34/35Ab1) Bt corn, a Cry1F Bt corn, and a non-Bt sweet corn; and in the laboratory among a Bt corn hybrid containing Cry1F, a hybrid containing Cry1Ab, a pyramid combining these two hybrids (Cry1F X Cry1Ab), and a non-Bt near isoline corn. In field experiments, we found that dispersal was significantly higher on Bt corn compared with sweet corn. In laboratory experiments, dispersal was significantly higher on Cry1Ab Bt corn and Cry1F X Cry1Ab Bt corn than on non-Bt near isoline corn. Results indicated that neonate dispersal may be significantly greater in Bt cornfields compared with non-Bt cornfields. The findings on dispersal behavior in this study will be useful in evaluating the efficacy of a blended seed refuge system for managing European corn borer resistance in Bt corn. PMID:22928300

  14. Le Indeterminacy in Spanish.

    ERIC Educational Resources Information Center

    Foster, David William

    The standard treatment of object pronouns in Latin American Spanish assigns a direct-object function to "lo" and "la" and an indirect-object function to "le." This study challenges this descriptive attribution in light of the contradictory and refractory evidence in Spanish morphosyntax. It is suggested that more detailed research, especially…

  15. Le Figaro. Revised.

    ERIC Educational Resources Information Center

    Crawford, Linda

    These instructional materials are designed for students with some French reading skills and vocabulary in late beginning or early intermediate senior high school French. The objectives are to introduce students to a French newspaper, "Le Figaro," and develop reading skills for skimming, gathering specific information, and relying on cognates. The…

  16. Improved corn protein based articles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing higher value uses for zein (corn protein), a potential major co-product of the bio-ethanol industry, will improve the economics of this business. Historically, zein was predominantly used in the textile fiber industry. Unfortunately the techniques used at that time to modify the zein cann...

  17. Sustainable Corn Stover Harvest Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn stover has been identified as an important initial source of biomass for conversion to ethanol and other biofuels. This poster presentation outlines on-going cooperative research being conducted near Ames, IA. Our university partner is responsible for developing the one-pass harvester and our I...

  18. Compatibility with corn: N credits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Productive and efficient short rotations of alfalfa and corn are needed to reduce energy inputs, produce food, feed, and energy, and yield the environmental quality benefits from the perennial legume. After decades of research, however, farmers and their advisors still question how much fertility ...

  19. Our Mother Corn. Teacher's Guide.

    ERIC Educational Resources Information Center

    Mathers, Sherry; And Others

    Designed to accompany the preceding student text (which deals with the role of corn in the Seneca, Pawnee, and Hopi tribes), the teaching guide contains a suggested sequence of activities and needed supplementary information along with an indication of the student text they follow. Sections include: farming notes; basic needs activities; house…

  20. Corn gluten meal application equipment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has determined that corn gluten meal (CGM) produces an inhibitory effect and reduces root formation in several weed species. One limitation to further evaluation of CGM in field vegetable production is the difficulty in achieving a uniform application to the soil surface. The use o...

  1. Effect of MIR604 transgenic maize at different stages of development on western corn rootworm (Coleoptera: Chrysomelidae) in a central missouri field environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The establishment and survival of western corn rootworm, Diabrotica virgifera virgifera LeConte, was evaluated on transgenic Bt maize, Zea mays L., expressing the mCry3A protein (MIR604) and non-Bt maize with the same genetic background (isoline maize) at different stages of development in 2007 and ...

  2. The Impact of MON863 Transgenic Roots is Equivalent on Western Corn Rootworm Larvae for a Wide Range of Maize Phenologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of maize (Zea mays L.) phenology on establishment, damage, and adult emergence of the western corn rootworm (Diabrotica virgifera virgifera LeConte) to MON863 transgenic maize expressing the Cry3Bb1 protein and its isoline was evaluated in field trials in 2002 and 2003. As expected, pla...

  3. Development of resistance to eCry3.1Ab-expressing transgenic maize in a laboratory-selected population of western corn rootworm (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A laboratory colony of western corn rootworm, Diabrotica virgifera virgifera LeConte, was selected for resistance to transgenic maize expressing the eCry3.1ab protein. The selected colony was developed by rearing larvae on non-elite, non-commercial Bt maize expressing the eCry3.1Ab protein. After ...

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

    DOE PAGESBeta

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

    2015-11-04

    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 bothmore » 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

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

    SciTech Connect

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

    2015-11-04

    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

  6. Le mouvement du pôle

    NASA Astrophysics Data System (ADS)

    Bizouard, Christian

    2012-03-01

    Les variations de la rotation terrestre. En conditionnant à la fois notre vie quotidienne, notre perception du ciel, et bon nombre de phénomènes géophysiques comme la formation des cyclones, la rotation de la Terre se trouve au croisement de plusieurs disciplines. Si le phenomena se faisait uniformément, le sujet serait vite discuté, mais c'est parce que la rotation terrestre varie, même imperceptiblement pour nos sens, dans sa vitesse angulaire comme dans la direction de son axe, qu'elle suscite un grand intérêt. D'abord pour des raisons pratiques : non seulement les aléas de la rotation terrestre modi_ent à la longue les pointés astrométriques à un instant donné de la journée mais in_uencent aussi les mesures opérées par les techniques spatiales ; en consequence l'exploitation de ces mesures, par exemple pour déterminer les orbites des satellites impliqués ou pratiquer le positionnement au sol, nécessite une connaissance précise de ces variations. Plus fondamentalement, elles traduisent les propriétés globales de la Terre comme les processus physiques qui s'y déroulent, si bien qu'en analysant les causes des fluctuations observées, on dispose d'un moyen de mieux connaître notre globe. La découverte progressive des fluctuations de la rotation de la Terre a une longue histoire. Sous l'angle des techniques d'observation, trois époques se pro-celle du pointé astrométrique à l'oeil nu, à l'aide d'instruments en bois ou métalliques (quart de cercle muraux par exemple). À partir du XVIIe siècle débute l'astrométrie télescopique dont les pointés sont complétés par des datations de plus en plus précises grâce à l'invention d'horloges régulées par balancier. Cette deuxième époque se termine vers 1960, avec l'avènement des techniques spatiales : les pointés astrométriques sont délaissés au profit de la mesure ultra-précise de durées ou de fréquences de signaux électromagnétiques, grâce à l'invention des horloges

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

    ERIC Educational Resources Information Center

    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…

  8. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  9. 7 CFR 810.401 - Definition of corn.

    Code of Federal Regulations, 2010 CFR

    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...

  10. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2010 CFR

    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...

  11. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  12. 21 CFR 137.265 - Degerminated white corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  13. 7 CFR 810.401 - Definition of corn.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 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...

  14. 21 CFR 137.265 - Degerminated white corn meal.

    Code of Federal Regulations, 2010 CFR

    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...

  15. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2010 CFR

    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...

  16. 7 CFR 810.401 - Definition of corn.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 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...

  17. 21 CFR 137.265 - Degerminated white corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  18. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  19. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  20. 21 CFR 137.265 - Degerminated white corn meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 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...

  1. 7 CFR 810.401 - Definition of corn.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 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...

  2. 21 CFR 137.265 - Degerminated white corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  3. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 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...

  4. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  5. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  6. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 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...

  7. 7 CFR 810.401 - Definition of corn.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 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...

  8. 75 FR 48321 - Corning Natural Gas Corporation; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-10

    ... Energy Regulatory Commission Corning Natural Gas Corporation; Notice of Application August 4, 2010. Take notice that on July 26, 2010, Corning Natural Gas Corporation (Corning), 330 W. William Street, Corning... Natural Gas Act (NGA) requesting the determination of a service area with which Corning may,...

  9. Fuel ethanol from raw corn

    SciTech Connect

    Weller, C.L.; Rodda, E.D.; Steinberg, M.P.

    1983-06-01

    Crude amylase preparations were produced by growing Aspergillus awamori and A. niger on raw ground whole corn. These Koji preparations were used to hydrolyze the starch of raw ground whole corn to sugars during simultaneous fermentation of the sugars to ethanol by distillers active dry yeast. Ethanol concentrations of the fermentation beers were determined with gas-chromatography. These fermentations yielded an average of 89.6% theoretical ethanol compared to control, conventional, fermentations that had an average of 89.8%. Carbon dioxide evolutions were determined with use of Alwood valves. Both the Koji and conventional fermentations produced an average of 0.48 gram of carbon dioxide per gram of dry substrate starch within 72 hours. However, initially the conventional fermentation rate was greater. Koji dehydrated at 41/sup 0/C had no apparent detrimental effects on theoretical ethanol yield.

  10. Fuel ethanol from raw corn

    SciTech Connect

    Weller, C.L.; Rodda, E.D.; Steinberg, M.P.

    1983-06-01

    Crude amylase preparations were produced by growing Aspergillus awamori and A. niger on raw ground whole corn. These Koji preparations were used to hydrolyze the starch of raw ground whole corn to sugars during simultaneous fermentation of the sugars to ethanol by distillers active dry yeast. Ethanol concentrations of the fermentation beers were determined with gas-chromatography. These fermentations yielded an average of 89.6% theoretical ethanol compared to control, conventional, fermentations that had an average of 89.8%. Carbon dioxide evolutions were determined with use of Alwood valves. Both the Koji and conventional fermentations produced an average of 0.48 gram of carbon dioxide per gram of dry substrate starch within 72 hours. However, initially the conventional fermentation rate was greater. Koji dehydrated at 41 degrees C had no apparent detrimental effects on theoretical ethanol yield.

  11. Field-evolved resistance to Bt maize by western corn rootworm: predictions from the laboratory and effects in the field.

    PubMed

    Gassmann, Aaron J

    2012-07-01

    Crops engineered to produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) provide an effective management tool for many key insect pests. However, pest species have repeatedly demonstrated their ability to adapt to management practices. Results from laboratory selection experiments illustrate the capacity of pest species to evolve Bt resistance. Furthermore, resistance has been documented to Bt sprays in the field and greenhouse, and more recently, by some pests to Bt crops in the field. In 2009, fields were discovered in Iowa (USA) with populations of western corn rootworm, Diabrotica virgifera virgifera LeConte, that had evolved resistance to maize that produces the Bt toxin Cry3Bb1. Fields with resistant insects in 2009 had been planted to Cry3Bb1 maize for at least three consecutive years and as many as 6years. Computer simulation models predicted that the western corn rootworm might evolve resistance to Bt maize in as few as 3years. Laboratory and field data for interactions between western corn rootworm and Bt maize indicate that currently commercialized products are not high-dose events, which increases the risk of resistance evolution because non-recessive resistance traits may enhance survival on Bt maize. Furthermore, genetic analysis of laboratory strains of western corn rootworm has found non-recessive inheritance of resistance. Field studies conducted in two fields identified as harboring Cry3Bb1-resistant western corn rootworm found that survival of western corn rootworm did not differ between Cry3Bb1 maize and non-Bt maize and that root injury to Cry3Bb1 maize was higher than injury to other types of Bt maize or to maize roots protected with a soil insecticide. These first cases of field-evolved resistance to Bt maize by western corn rootworm provide an early warning and point to the need to apply better integrated pest management practices when using Bt maize to manage western corn rootworm. PMID:22537837

  12. Effect of soybean varieties on survival and fecundity of western corn rootworm.

    PubMed

    Dunbar, Mike W; Gassmann, Aaron J

    2012-04-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a major pest of corn (Zea mays L.) in North America and has evolved resistance to crop rotation by ovipositing in alternate crops such as soybeans [Glycine max (L.) Merr.]. Through experiments with plants grown in the greenhouse and the field, we tested whether soybeans with resistance to the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), affected survival, fecundity, and consumption of soybean for D. v. virgifera. Soybean varieties tested included those types resistant to A. glycines (Rag1 and rag1/rag3) and a susceptible near isoline of the Rag1 variety. Females were provided with a diet of corn tissue for 4 d after which they were fed a diet of tissue from one of three soybean varieties for 4 d, starved for 4 d, or fed corn tissue. When fed greenhouse grown plants, strains differed significantly in survival and consumption, but consumption did not differ by variety of soybean. Diet treatment only affected fecundity; individuals fed corn continuously had greater fecundity than those individuals fed soybeans. In the experiment with plants grown in the field, leaf consumption differed among strains and individuals fed corn continuously had greater fecundity than the other treatments. Soybean varieties with Rag1 and rag1/rag3 resistance to A. glycines did not appear to affect the fitness of D. v. virgifera. Thus, planting of these A. glycines-resistant soybean varieties should not directly affect the spread of rotation-resistant D. v. virgifera. PMID:22606835

  13. Western corn rootworm larval movement in SmartStax seed blend scenarios.

    PubMed

    Zukoff, Sarah N; Bailey, Wayne C; Ellersieck, Mark R; Hibbard, Bruce E

    2012-08-01

    Insect resistance management (IRM) can extend the lifetime of management options, but depends on extensive knowledge of the biology of the pest species involved for an optimal plan. Recently, the Environmental Protection Agency (EPA) registered seed blends refuge for two of the transgenic Bacillus thuringiensis (Bt) corn products targeting the western corn rootworm, Diabrotica virgifera virgifera LeConte. Larval movement between Bt and isoline plants can be detrimental to resistance management for high dose Bt products because the larger larvae can be more tolerant of the Bt toxins. We assessed movement of western corn rootworm larvae among four spatial arrangements of SmartStax corn (expressing both the Cry34/35Ab1 and Cry3Bb1 proteins) and isoline plants by infesting specific plants with wild type western corn rootworm eggs. Significantly fewer western corn rootworm larvae, on average, were recovered from infested SmartStax plants than infested isoline plants, and the SmartStax plants were significantly less damaged than corresponding isoline plants. However, when two infested isoline plants surrounded a SmartStax plant, a significant number of larvae moved onto the SmartStax plant late in the season. These larvae caused significant damage both years and produced significantly more beetles than any other plant configuration in the study (including isoline plants) in the first year of the study. This plant configuration would occur rarely in a 5% seed blend refuge and may produce beetles of a susceptible genotype because much of their initial larval development was on isoline plants. Results are discussed in terms of their potential effects on resistance management. PMID:22928304

  14. Production and analysis of citrinin in corn.

    PubMed Central

    Jackson, L K; Ciegler, A

    1978-01-01

    A convenient method for the production and analysis of citrinin in corn is described. Up to 2.964 g of citrinin can be produced by Penicillium citrinum per kg of corn by harvesting on day 21 or later. The analysis method has a lower detection limit of 0.25 ppm. Heating citrinin-contaminated corn destroys citrinin but may produce another toxin instead. PMID:727774

  15. Exploring Management Options for Increasing Corn Land on NY Farms Affected by Rising Corn Prices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New York dairy farms use their most fertile land to produce corn silage, an important component of their production system. Increasing demand for corn by ethanol producers is driving up corn grain prices. This is introducing a major shift into the NY dairy farm system by prompting farmers to place m...

  16. Potential Harvestable Corn Cob Biomass in Several Production Systems in the Western Corn Belt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The proposed use of corn residues for biofuel production has increased interest in how much and what components of residue should/can be removed. One component of corn residue that is already being handled (corn cobs) might be an easily harvestable product that could be used for biofuel production. ...

  17. EFFECT OF SAMPLE PROCESSING PROCEDURES ON MEASUREMENT OF STARCH IN CORN SILAGE AND CORN GRAIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods for processing feedstuffs before analysis can affect analytical results. The effects of drying temperature and grinding method on starch analysis of corn silage and of grinding method on corn grain were evaluated. Corn silage samples dried at 55°C or 105°C and grain samples dried at 55°C w...

  18. Prevalence of a gene conferring sensitivity to nicosulfuron and mesotrione in sweet corn and field corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In previous research, a single gene in a herbicide-sensitive sweet corn inbred, Cr1, conditioned sensitivity to nicosulfuron, mesotrione and other postemergence herbicides. Many other sweet corn hybrids and inbreds and certain field corn inbreds also have been noted as being sensitive to certain po...

  19. The development of a "Green" aqueous enzymatic process to extract corn oil from corn germ

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Approximately 2.4 million tons of commercial corn oil were produced worldwide in 2012, compared to 2012 world production of palm oil (53.3 MT) and soybean oil (43.1 MT) according to FAS, USDA. Most commercial corn oil (~90%) is produced from corn germ that is expeller pressed and/or hexane extracte...

  20. Evaluation of Elevated Dietary Corn Fiber from Corn Germ Meal in Growing Female Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the effects of high dietary corn fiber on growth and metabolic measures, female pigs (n= 48; initial body weight of 30.8 kg) were fed diets containing 0 to 38.6% solvent-extracted corn germ meal for 28 days. Increasing the level of dietary corn fiber had no impact on average daily gain o...

  1. Impact of corn variety on potential predators of larval corn rootworms (Coleoptera: Diabrotica spp.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn rootworms (Coleoptera: Diabrotica spp.) are serious pests of maize around the world. Larvae feed on corn roots, which reduces uptake of water and nutrients and lowers plant yield. Current control practices rely on soil insecticides or genetically modified corn varieties. Although some researche...

  2. Understanding successful resistance management: The European corn borer and Bt corn in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    European corn borer, Ostrinia nubilalis Hubner (Lepidoptera: Crambidae) has been a major pest of corn and other crops in North America since its accidental introduction nearly a hundred years ago. Wide adoption of transgenic corn that expresses toxins from Bacillus thuringiensis, referred to as Bt c...

  3. Proteins induced in corn (Zea mays) in response to the European corn borer (Ostrinia nubilalis)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The European corn borer (ECB, Ostrinia nubilalis) is a major pest of corn. ECB begin by feeding in the whorl tissue and then eventually tunnel into the stalk of the corn where they cause most of the damage. Tunneling can disrupt the transport of water and nutrients in the plant and it provides sites...

  4. 3. Interior view of corn crib showing heavytimber framing, railed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Interior view of corn crib showing heavy-timber framing, railed trackway and corn car at upper level. - Laurel Valley Sugar Plantation, Corn Crib, 2 miles South of Thibodaux on State Route 308, Thibodaux, Lafourche Parish, LA

  5. Gut bacteria facilitate adaptation to crop rotation in the western corn rootworm.

    PubMed

    Chu, Chia-Ching; Spencer, Joseph L; Curzi, Matías J; Zavala, Jorge A; Seufferheld, Manfredo J

    2013-07-16

    Insects are constantly adapting to human-driven landscape changes; however, the roles of their gut microbiota in these processes remain largely unknown. The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) (Coleoptera: Chrysomelidae) is a major corn pest that has been controlled via annual rotation between corn (Zea mays) and nonhost soybean (Glycine max) in the United States. This practice selected for a "rotation-resistant" variant (RR-WCR) with reduced ovipositional fidelity to cornfields. When in soybean fields, RR-WCRs also exhibit an elevated tolerance of antiherbivory defenses (i.e., cysteine protease inhibitors) expressed in soybean foliage. Here we show that gut bacterial microbiota is an important factor facilitating this corn specialist's (WCR's) physiological adaptation to brief soybean herbivory. Comparisons of gut microbiota between RR- and wild-type WCR (WT-WCR) revealed concomitant shifts in bacterial community structure with host adaptation to soybean diets. Antibiotic suppression of gut bacteria significantly reduced RR-WCR tolerance of soybean herbivory to the level of WT-WCR, whereas WT-WCR were unaffected. Our findings demonstrate that gut bacteria help to facilitate rapid adaptation of insects in managed ecosystems. PMID:23798396

  6. 6-Methoxy-2-benzoxazolinone: A semiochemical for host location by western corn rootworm larvae.

    PubMed

    Bjostad, L B; Hibbard, B E

    1992-07-01

    A bioassay-driven sequential fractionation scheme was used to isolate all portions of a crude dichloromethane corn seedling extract behaviorally active to larvae of the western corn rootworm,Diabrotica virgifera virgifera LeConte. 6-Methoxy-2-benzoxazolinone (MBOA) was identified as one of the most important components of an attractive crude corn extract. MBOA was found on or in the intact root tissues by injecting an extract of undamaged roots onto an HPLC immediately after extraction. MBOA was demonstrated to be volatile and functions as a semiochemical in conjunction with carbon dioxide in host location by western corn rootworm larvae, which are oligophagous on the roots of maize and several other species of grasses. Because MBOA occurs almost exclusively in maize and other grasses, it offers a simple way for the larvae to distinguish possible hosts from non-hosts. MBOA has previously been reported as a chemical defense against other insect species. This is the first report in grasses of a secondary compound that is toxic or a deterrent to nonadapted insect herbivores but that is used as a semiochemical in host location by a specialist insect species. PMID:24254139

  7. Influence of western corn rootworm (Coleoptera: Chrysomelidae) larval injury on yield of different types of maize.

    PubMed

    Urías-López, M A; Meinke, L J

    2001-02-01

    Two field experiments were conducted in 1995-1996 to determine if there are common yield responses among maize hybrids to larval western corn rootworm, Diabrotica virgifera virgifera LeConte injury. Three yellow dent hybrids, five white food grade dent hybrids, and a popcorn hybrid were included in the study. The minimum level of rootworm injury as measured by root damage ratings (3.2-4.2) that significantly reduced yield was similar across the hybrids included in the study. However, the pattern of yield response to different rootworm injury levels varied among hybrids. This suggests that maize hybrids may inherently differ in their ability to tolerate rootworm injury and partition biomass in response to injury and other stresses. The complex interaction among hybrid, level of injury, and other stresses suggests that a common western corn rootworm injury-yield relationship may not exist within maize. PMID:11233098

  8. Lipid, polyamide, and flavonol phagostimulants for adult western corn rootworm from sunflower (Helianthus annuus L.) pollen.

    PubMed

    Lin, S; Mullin, C A

    1999-03-01

    Adult Diabroticites including western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, consume pollen of corn, squash, sunflower, and other species. Short-chain neutral amino acids in methanol-water extracts of pollen have been previously identified in our laboratory as strong phagostimulants for Diabrotica. Bioassay-driven fractionation was used to characterize the interacting lipid and midpolarity phagostimulants for adult WCR in Giant Gray Stripe sunflower, Helianthus annuus L., pollen. Lipids rich in omega3-linolenic acid including triglycerides, free fatty acids, phosphatidylethanolamines, phosphatidic acids, and phosphatidylcholines were highly phagostimulatory. Other important phagostimulatory components included a hydroxycinnamic acid-polyamine amide, N(1),N(5),N(10)-tri[(E)-p-coumaroyl]spermidine, and a flavonol, quercetin beta-3-O-glucoside. The structural characteristics of these phagoactive compounds and their role in the pollinivory specialization of rootworm beetles are discussed. PMID:10552441

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

    PubMed

    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

  10. Starlink corn: a risk analysis.

    PubMed Central

    Bucchini, Luca; Goldman, Lynn R

    2002-01-01

    Modern biotechnology has dramatically increased our ability to alter the agronomic traits of plants. Among the novel traits that biotechnology has made available, an important group includes Bacillus thuringiensis-derived insect resistance. This technology has been applied to potatoes, cotton, and corn. Benefits of Bt crops, and biotechnology generally, can be realized only if risks are assessed and managed properly. The case of Starlink corn, a plant modified with a gene that encodes the Bt protein Cry9c, was a severe test of U.S. regulatory agencies. The U.S. Environmental Protection Agency had restricted its use to animal feed due to concern about the potential for allergenicity. However, Starlink corn was later found throughout the human food supply, resulting in food recalls by the Food and Drug Administration and significant disruption of the food supply. Here we examine the regulatory history of Starlink, the assessment framework employed by the U.S. government, assumptions and information gaps, and the key elements of government efforts to manage the product. We explore the impacts on regulations, science, and society and conclude that only significant advances in our understanding of food allergies and improvements in monitoring and enforcement will avoid similar events in the future. Specifically, we need to develop a stronger fundamental basis for predicting allergic sensitization and reactions if novel proteins are to be introduced in this fashion. Mechanisms are needed to assure that worker and community aeroallergen risks are considered. Requirements are needed for the development of valid assays so that enforcement and post market surveillance activities can be conducted. PMID:11781159

  11. Impact of the Bt Corn Proteins Cry34/35Ab1 and Cry3Bb1, Alone or Pyramided, on Western Corn Rootworm (Coleoptera: Chrysomelidae) Beetle Emergence in the Field.

    PubMed

    Hitchon, A J; Smith, J L; French, B W; Schaafsma, A W

    2015-08-01

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major pest of corn, Zea mays L. The effect of the Bt proteins Cry34/35Ab1 and Cry3Bb1, alone or pyramided in corn hybrids on D. v. virgifera adult emergence was evaluated in field experiments for 3 yr. Experiments were infested artificially with 2,500 viable D. v. virgifera eggs per row meter of corn. The reduction in beetle emergence compared with non-Bt controls, from Cry34/35Ab1, Cry3Bb1, and the pyramided hybrids ranged from 64.3 to 97.4%, 91.1 to 95.2%, and 98.1 to 99.6%, respectively. The sex ratio of emerged beetles was usually female-biased from the Cry3Bb1 and pyramided treatments, but not from Cry34/35Ab1 treatment alone. Emergence from all Bt hybrids was delayed compared with the control, with the delay longest from the pyramided hybrid. In 2013, three egg infestation levels were tested, with density-dependent mortality observed at 1,250 viable eggs per row meter. The effect of Bt proteins on the emergence timing and sex ratio of D. v. virgifera may impact the suitability of resistance management plans, specifically the effectiveness of the refuge strategy. Susceptible males emerging from refuge might not be synchronized to mate with potentially resistant females emerging later from Bt corn hybrids. PMID:26470344

  12. CONVERSION OF CORN FIBROUS MATERIAL INTO ETHANOL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 1.7 billion gallons of fuel ethanol were produced in the U.S. (2001), over 90% of which was produced from corn. Corn is prepared for ethanol fermentation by either wet milling or dry grinding in approximately equal volumes. In both processes, the fibrous components of the kernel are folded in...

  13. Corn production with Spray, LEPA, and SDI

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn, a major irrigated crop in the U.S. Great Plains, has a large irrigation requirement making efficient, effective irrigation technology important. The objective of this paper was to compare corn productivity for different irrigation methods and irrigation rates in 2009 and 2010 at Bushland, Texa...

  14. Climate forecasts for corn producer decision making

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. Corn fiber utilization for production of Schizophyllan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber is an abundant coproduct of the corn wet milling process, primarily composed of the seed pericarp and adherent starch. Schizophyllan is a biopolymer composed entirely of glucose, with a ß-1,3-linked backbone and single ß-1,6-linked glucose side chains at every third residue, produced by t...

  16. Sweet Corn Hybrid Disease Nursery - 2009

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report summarizes the reactions of 387 sweet corn hybrids to Stewart’s wilt, common rust, maize dwarf mosaic virus, Southern leaf blight, and Northern leaf blight based on their performance in the University of Illinois sweet corn disease nursery in 2009. The reactions of these hybrids to three...

  17. INTACT OR UNIT-KERNEL SWEET CORN

    EPA Science Inventory

    This report evaluates process and product modifications in canned and frozen sweet corn manufacture with the objective of reducing the total effluent produced in processing. In particular it evaluates the proposed replacement of process steps that yield cut or whole kernel corn w...

  18. The corn blight problem: 1970 and 1971

    NASA Technical Reports Server (NTRS)

    Bauer, M. E.

    1972-01-01

    Southern corn leaf blight is caused by the fungus, Helminthosporium maydis. Race T of H maydis adapted itself to the Texas male sterile cytoplasm corn. The problems caused by this variety of the blight in 1970 and 1971 are discussed, as well as the symptoms and development of the disease.

  19. Integrated Corn-Based Bio-Refinery

    SciTech Connect

    2006-04-01

    The Integrated Corn-Based Bio-Refinery (ICBR) process will use new technology to convert corn grain and stover into fermentable sugars for the parallel production of value-added chemicals such as 1,3-propanediol (PDO) and fuel ethanol.

  20. Erraticity of sprinkler irrigated corn in 2011

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sprinkler non-uniformity effects on corn are accentuated in a drought. The lack of rainfall during the 2011 corn growing season in Colby, Kansas illustrated many fields irrigated by center pivot sprinklers that had poor crops due to non-uniform irrigation. Many of these effects were due to use of ...

  1. Sweet Corn Hybrid Disease Nursery - 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report summarizes the reactions of 439 sweet corn hybrids to Stewart’s wilt, common rust, maize dwarf mosaic virus, Southern leaf blight, and Northern leaf blight based on their performance in the University of Illinois sweet corn disease nursery in 2010. The reactions of these hybrids to two h...

  2. Active sensor assessment of corn nitrogen status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of active sensor measurements of in-season corn (Zea mays L.) nitrogen (N) status for directing spatially-variable N applications has been advocated to improve N use efficiency. However, first it is necessary to confirm that active sensors can reliably assess corn N status. Our research goals we...

  3. Critical Precipitation Period for Dryland Corn Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grain yields for dryland corn (Zea mays L.) production in the semi-arid Great Plains of the United States can be very unpredictable because of the erratic nature of growing season precipitation. Because inputs costs for corn production can be very high, farmers need to have a tool that will help the...

  4. Corn plant locating by image processing

    NASA Astrophysics Data System (ADS)

    Jia, Jiancheng; Krutz, Gary W.; Gibson, Harry W.

    1991-02-01

    The feasibility investigation of using machine vision technology to locate corn plants is an important issue for field production automation in the agricultural industry. This paper presents an approach which was developed to locate the center of a corn plant using image processing techniques. Corn plants were first identified using a main vein detection algorithm by detecting a local feature of corn leaves leaf main veins based on the spectral difference between mains and leaves then the center of the plant could be located using a center locating algorithm by tracing and extending each detected vein line and evaluating the center of the plant from intersection points of those lines. The experimental results show the usefulness of the algorithm for machine vision applications related to corn plant identification. Such a technique can be used for pre. cisc spraying of pesticides or biotech chemicals. 1.

  5. Soil application of an encapsulated CO2 source and its potential for management of western corn rootworm larvae.

    PubMed

    Schumann, M; Patel, A; Vidal, S

    2014-02-01

    Western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae use carbon dioxide (CO2) to locate the roots of their hosts. This study investigated whether an encapsulated CO2 source (CO2-emitting capsules) is able to outcompete CO2 gradients established by corn root respiration in the soil. Furthermore, the following two management options with the capsules were tested in semifield experiments (0.5- to 1-m2 greenhouse plots): the disruption of host location and an "attract-and-kill" strategy in which larvae were lured to a soil insecticide (Tefluthrin) between the corn rows. The attract-and-kill strategy was compared with an application of Tefluthrin in the corn rows (conventional treatment) at 33 and 18% of the standard field application rate. Application of the CO2-emitting capsules 30 cm from the plant base increased CO2 levels near the application point for up to 20 d with a peak at day 10. Both the disruption of host location and an attract-and-kill strategy caused a slight but nonsignificant reduction in larval densities. The disruption of host location caused a 17% reduction in larval densities, whereas an attract-and-kill strategy with Tefluthrin added at 33 and 18% of the standard application rate caused a 24 and 27% reduction in larval densities, respectively. As presently formulated, the CO2-emitting capsules, either with or without insecticide, do not provide adequate control of western corn rootworm. PMID:24665706

  6. Insecticidal activity of monoterpenoids to western corn rootworm (Coleoptera: Chrysomelidae), twospotted spider mite (Acari: Tetranychidae), and house fly (Diptera: Muscidae).

    PubMed

    Lee, S; Tsao, R; Peterson, C; Coats, J R

    1997-08-01

    Acute toxicities of 34 naturally occurring monoterpenoids were evaluated against 3 important arthropod pest species; the larva of the western corn rootworm, Diabrotica virgifera virgifera LeConte; the adult of the twospotted spider mite. Tetranychus urticae Koch; and the adult house fly. Musca domestica L. Potential larvicidal or acaricidal activities of each monoterpenoid were determined by topical application, leaf-dip method, soil bioassay, and greenhouse pot tests. Phytotoxicity was also tested on a corn plant. Citronellic acid and thymol were the most topically toxic against the house fly, and citronellol and thujone were the most effective on the western corn rootworm. Most of the monoterpenoids were lethal to the twospotted spider mite at high concentrations; carvomenthenol and terpinen-4-ol were especially effective. A wide range of monoterpenoids showed some larvicidal activity against the western corn rootworm in the soil bioassay. Perillaldehyde, the most toxic (LC50 = 3 micrograms/g) in soil, was only 1/3 as toxic as carbofuran, a commercial soil insecticide (LC50 = 1 microgram/g). Selected monoterpenoids also effectively protected corn roots from attack by the western corn rootworm larvae under greenhouse conditions. alpha-Terpineol was the best monoterpenoid in the greenhouse pot test. The acute toxicity of monoterpenoids was low relative to conventional insecticides. Some monoterpenoids were phytotoxic to corn roots and leaves. l-Carvone was the most phytotoxic, whereas pulegone was the safest. The results with thymyl ethyl ether, one of the synthetic derivatives of thymol, showed a potential of derivatization to reduce monoterpenoid phytotoxicity. PMID:9260540

  7. Genetic monitoring of western corn rootworm (Coleoptera: Chrysomelidae) populations on a microgeographic scale.

    PubMed

    Ivkosic, S A; Gorman, J; Lemic, D; Mikac, K M

    2014-06-01

    Microsatellite and mitochondrial DNA genetic monitoring of the western corn rootworm, Diabrotica virgifera virgifera LeConte, was undertaken in Croatia and Serbia from 1996 to 2011 and in the United States in 2011. The seven U.S. populations displayed the greatest allelic diversity. In Europe, the highest number of alleles was found in Rugvica, Croatia, and Surčin, Serbia, the two sites closest to international airports. The highest number of mitochondrial (mt) DNA haplotypes was recorded from Croatia in 1996. From 2009 to 2011, haplotype diversity declined, and Croatia and Serbia had a single fixed haplotype. U.S. continuous maize locations had one haplotype, while three haplotypes were found at crop-rotated locations. Minimal temporal genetic differentiation was found within and between populations in Europe and the United States. Bayesian cluster analysis identified two genetic clusters that grouped western corn rootworm from Croatia and Serbia separately from U.S. populations; however, these clusters were not neat, and numerous U.S. individuals had both European and U.S. ancestry, suggesting bidirectional gene flow. Bottlenecks were identified within most Croatian populations sampled in 1996, only two populations in 2009, and in all populations in 2011. Bottlenecks were not identified from Serbia from 1996 to 2011 or from the United States in 2011. As suspected Serbia was identified as the geographic source of western corn rootworm in Croatia. The temporal genetic monitoring undertaken allowed a deeper understanding of the population genetics of western corn rootworm in Croatia, neighboring Serbia, and its geographic source in the United States. The data obtained can be used to inform western corn rootworm pest management strategies in Croatia and Europe. PMID:24690224

  8. Western corn rootworm and Bt maize: challenges of pest resistance in the field.

    PubMed

    Gassmann, Aaron J; Petzold-Maxwell, Jennifer L; Keweshan, Ryan S; Dunbar, Mike W

    2012-01-01

    Crops genetically engineered to produce insecticidal toxins from the bacterium Bacillus thuringiensis (Bt) manage many key insect pests while reducing the use of conventional insecticides. One of the primary pests targeted by Bt maize in the United States is the western corn rootworm, Diabrotica virgifera virgifera LeConte. Beginning in 2009, populations of western corn rootworm were identified in Iowa, USA that imposed severe root injury to Cry3Bb1 maize. Subsequent laboratory bioassays revealed that these populations were resistant to Cry3Bb1 maize, with survival on Cry3Bb1 maize that was three times higher than populations not associated with such injury. Here we report the results of research that began in 2010 when western corn rootworm were sampled from 14 fields in Iowa, half of which had root injury to Cry3Bb1 maize of greater than 1 node. Of these samples, sufficient eggs were collected to conduct bioassays on seven populations. Laboratory bioassays revealed that these 2010 populations had survival on Cry3Bb1 maize that was 11 times higher and significantly greater than that of control populations, which were brought into the laboratory prior to the commercialization of Bt maize for control of corn rootworm. Additionally, the developmental delays observed for control populations on Cry3Bb1 maize were greatly diminished for 2010 populations. All 2010 populations evaluated in bioassays came from fields with a history of continuous maize production and between 3 and 7 y of Cry3Bb1 maize cultivation. Resistance to Cry34/35Ab1 maize was not detected and there was no correlation between survival on Cry3Bb1 maize and Cry34/35Ab1 maize, suggesting a lack of cross resistance between these Bt toxins. Effectively dealing with the challenge of field-evolved resistance to Bt maize by western corn rootworm will require better adherence to the principles of integrated pest management. PMID:22688688

  9. Larval sampling and instar determination in field populations of northern and western corn rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Hammack, Leslie; Ellsbury, Michael M; Roehrdanz, Richard L; Pikul, Joseph L

    2003-08-01

    Abundance and head capsule width were measured for northern (Diabrotica barberi Smith & Lawrence) and western corn rootworm (D. virgifera virgifera LeConte) larvae recovered primarily from maize root systems but also from large soil cores each centered around a root system. Larvae for measurement derived from field populations under infestation and rotation regimes that allowed most specimens to be assigned to species. A frequency distribution of head capsule widths indicated three separate peaks for western corn rootworm, presumably representing frequency of the three larval instars, with no larvae measuring 280 or 420 microm in the valleys between peaks. Multiple normal curves fit to similar but partially overlapping peaks generated by northern corn rootworm suggested that division of first to second and second to third instar can best be made for this species at 267 and 406 microm, respectively (270 and 410 when measurements are made to the nearest 20 microm). These results implied that instar of individuals from mixed northern and western corn rootworm populations can be accurately judged from head capsule width without having to determine species. The relative abundance of western corn rootworm instars was similar in root systems removed from the center of 19-cm diameter x 19-cm deep soil cores and in soil cores from which the root systems were removed. Furthermore, the number of larvae from root systems correlated significantly with that from the surrounding soil. These results indicated that the former and much more convenient sampling unit can be used to estimate population developmental stage and possibly density, at least early in the season when these tests were done and young larvae predominated. PMID:14503586

  10. Multipass rotary shear comminution process to produce corn stover particles

    DOEpatents

    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.

  11. Native Resistance of Maize to Western Corn Rootworm Larval Feeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western corn rootworm (WCR) is a major insect pest in continuous corn production. By feeding on corn roots, WCR causes economic losses due to plant lodging and decreased nutrient uptake. Currently, insecticides and transgenic corn are only available options for its control under continuous cor...

  12. Possible causes of dry pea synergy to corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  13. Studies of Corn Stover Decomposition Using the Litter Bag Technique

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decomposition rates of residue from three genetically-modified corn hybrids expressing one or more Bt endotoxins were compared to that of residue from a near isogenic, unmodified hybrid. The corn hybrids were (i) DKC60-16 (Yieldguard Corn Borer), (ii) DKC60-12 (Yieldguard Corn Rootworm), (iii) DKC60...

  14. Pilot process for decolorizing/deodorizing commercial corn zein products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn zein is the major protein component of ground corn, and co-products of the corn ethanol industry which includes distiller’s dried grains and corn gluten meal. Zein products generated from those materials all possess some degree of yellow color and off-odor that deters their usage in food syste...

  15. On-Farm Validation of Alfalfa N Credits to Corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rotating alfalfa with corn is useful for reducing soil erosion, enhancing soil tilth and carbon storage, reducing weed seedbanks, disrupting the life cycles of disease and insect pests of corn, and supplying nitrogen (N) to the subsequent corn crop. To adjust N fertilizer rates for corn following al...

  16. 21 CFR 137.255 - Bolted white corn meal.

    Code of Federal Regulations, 2010 CFR

    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...

  17. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  18. 21 CFR 137.280 - Bolted yellow corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  19. 21 CFR 137.255 - Bolted white corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 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...

  20. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2010 CFR

    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...

  1. 21 CFR 137.280 - Bolted yellow corn meal.

    Code of Federal Regulations, 2010 CFR

    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...

  2. 21 CFR 137.280 - Bolted yellow corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  3. 21 CFR 137.211 - White corn flour.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false White corn flour. 137.211 Section 137.211 Food and... Related Products § 137.211 White corn flour. (a) White corn flour is the food prepared by so grinding and bolting cleaned white corn that when tested by the method prescribed in paragraph (b)(2) of this...

  4. 21 CFR 137.255 - Bolted white corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  5. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 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...

  6. 21 CFR 137.211 - White corn flour.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false White corn flour. 137.211 Section 137.211 Food and... Related Products § 137.211 White corn flour. (a) White corn flour is the food prepared by so grinding and bolting cleaned white corn that when tested by the method prescribed in paragraph (b)(2) of this...

  7. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  8. 21 CFR 137.211 - White corn flour.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false White corn flour. 137.211 Section 137.211 Food and... Related Products § 137.211 White corn flour. (a) White corn flour is the food prepared by so grinding and bolting cleaned white corn that when tested by the method prescribed in paragraph (b)(2) of this...

  9. 21 CFR 137.280 - Bolted yellow corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 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...

  10. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 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...