Survival and Growth of Two \u3ci\u3eHydraecia\u3c/i\u3e Species (Noctuidae: Lepidoptera) on Eight Midwest Grass Species

Grasses play a critical role in the life cycles of both the hop vine borer (Hydraecia immanis) and potato stem borer (H. micacea), two potentially se­rious agriculture pests. Neonate larvae of both species (Noctuidae: Lepidoptera) were reared on eight selected grasses and corn for 14-18 days under greenhouse conditions to determine their survival and growth. These were quackgrass (Agropyron repens), smooth bromegrass (Bromus inermis), orchardgrass (Dactylis glomerata), large crabgrass (Digitaria sanguinalis), barnyardgrass (Echinochloa crusgalli), giant foxtail (Seteria faberii), wild prosso millet (Panicum millaceum), Johnsongrass (Sorghum halepense), and corn (Zea mays). In a separate, concurrent experiment, H. immanis and H. micacea larvae were reared on quackgrass, smooth bromegrass and orchardgrass (narrow-stemmed grasses) and sampled after 7, 10 and 14 days. H. immanis larvae generally grew more slowly and dispersed less quickly than H. micacea larvae. The fewest H. immanis and H. micacea larvae were recovered from giant foxtail. H. immanis larvae reared on quackgrass, smooth bromegrass and orchardgrass (thin-stemmed grasses) outgrew their hosts by the third instar and rapidly dispersed, particularly from quackgrass. Due to the unique internal stem-feeding behavior of these larvae the stem thickness becomes a constraining factor regarding duration of suitability to serve as a larval host. Grass feeding has tremendous significance regarding the geographic spread, local population densities, phenological damage periods, and cultural control methods such as crop rotation for these two noctuid species

Effects of Corn and Selected Weed Species on Feeding Behavior of the Stalk Borer, \u3ci\u3ePapaipema Nebris\u3c/i\u3e (Lepidoptera: Noctuidae)

Experiments were conducted in an outdoor insectary to examine behavioral interactions between fifth instar stalk borers, Papaiperna nebris, and potential host plant species. Plants tested included 6- and 8-leaf stage corn, Zea mays, and ten weed species (six broadleaf and four grass) commonly associated with corn production in southern Wisconsin. Broadleaf plants found to be acceptable hosts included Ambrosia trifida, Arnaranthus retroflexus, Rumex crispus, and Chenopodium album; Asclepias syriaca and Abutilon theophrasti were not acceptable as host plants. Corn and the other grass species (Agropyron repens, Bromus inermis, Dactylis glomerata, and Setaria faberi) were found to be acceptable hosts. All acceptable plants also supported larval development to the pupal stage, though on 6-leaf stage corn and the small-stemmed grasses the majority of larvae dispersed before completing development. Larvae developing on corn, A. triftda, and A. retroflexus pupated within the plant stem, whereas larvae developing on the other plants pupated in the soil near the plant on which they fed. Stalk borer larvae required substantially less time to bore into corn stalks than into the stems of the broadleaf plants. In a limited preference experiment, corn was clearly preferred as a host plant over the three broadleaf and one small-stemmed grass species tested

Suitability of Selected Broad-Leaved Weeds for Survival and Growth of Two Stalk-Boring \u3ci\u3eHydraecia\u3c/i\u3e Species (Lepidoptera: Noctuidae)

Third instar hop vine borer (Hydraecia immanis) and potato stem borer (H. micacea) are new pest species on corn in the Midwest. Early instar larvae feed on small-stemmed grasses, and later instar larvae switch to broad- stemmed hosts to complete development. In order to assess potential suitability of various weeds of corn fields, larvae were reared on seven selected broad- leaved plants for 16-18 days under greenhouse conditions to determine their feeding behavior and performance. Domestic plants included hop (Humulus lupulus) and potato (Solanum tuberosum); weed species included curly dock (Rumex crisp us), redroot pigweed (Amaranthus retroflexus), lambsquarters (Chenopodium album), common ragweed (Ambrosia artemisiifolia) and giant ragweed (A. trifida). Larvae of both species survived best on corn, hop, and curly dock. While potato was an excellent host for the potato stem borer H. micacea, survival was poor for the hop vine borer, H. immanis. Red root pigweed, common ragweed, giant ragweed and lambsquarters were poor hosts for both moth species. While the potato stem borer, H. micacea, larvae were able to grow well and gain weight rapidly on several hosts, the hop stem borer, H. immanis, grew well only on hops. Larval feeding behavior and size, as well as plant phenology, stem thickness, and growth form, are all critical determinants as to whether or not a particular plant species can serve as a final host on which H. immanis and H. micacea can complete development

Bionomics of Insects Associated with Corn in the Nebraska Sandhills

Investigations were conducted in the Nebraska Sandhills to determine the impact of transition from grassland to irrigated corn on selected insect species, to identify indigenous species that may be economically important to corn production, and to provide a point of reference for future development of pest management programs for irrigated corn

A system of relational syllogistic incorporating full Boolean reasoning

We present a system of relational syllogistic, based on classical propositional logic, having primitives of the following form: Some A are R-related to some B; Some A are R-related to all B; All A are R-related to some B; All A are R-related to all B. Such primitives formalize sentences from natural language like `All students read some textbooks'. Here A and B denote arbitrary sets (of objects), and R denotes an arbitrary binary relation between objects. The language of the logic contains only variables denoting sets, determining the class of set terms, and variables denoting binary relations between objects, determining the class of relational terms. Both classes of terms are closed under the standard Boolean operations. The set of relational terms is also closed under taking the converse of a relation. The results of the paper are the completeness theorem with respect to the intended semantics and the computational complexity of the satisfiability problem.Comment: Available at http://link.springer.com/article/10.1007/s10849-012-9165-

Absence of the spleen(s) in conjoined twins: a diagnostic clue of laterality defects? Radiological study of historical specimens

Laterality defects are quite common in thoracoileopagus and parapagus dicephalus but rare in other types of conjoined twins. To present the presumed laterality defects in cephalothoracoileopagus and prosopothoracoileopagus conjoined twins, based on the unilateral or bilateral absence or duplication of the spleen. Three human anatomical specimens of craniothoracoileopagus (CTIP) twins and one of prosopothoracoileopagus (PTIP) twins were investigated. The specimens were part of the Museum Vrolik collection of the Department of Anatomy and Embryology of the Academic Medical Centre, University of Amsterdam, The Netherlands. The specimens were taken out of their jars and scanned with multidetector CT and volumetric T2-weighted MRI at 1.5 T. The internal anatomy of the specimens was largely in accordance with previous reports. However, there was no recognisable spleen in the right twin in one CTIP specimen, in the left twin in one other CTIP specimen, and in both twins in the third CTIP specimen and in the PTIP specimen. Asplenia and polysplenia are considered reliable indicators of right and left isomerism, respectively. However, three of our four specimens had laterality patterns that did not correspond with those previously reported. Since no other parameters of laterality defects could be verified in these specimens, we concluded that asplenia was unlikely to be caused by laterality defect

Computer-Aided Solvent Screening for Biocatalysis

A computer-aidedsolventscreening methodology is described and tested for biocatalytic systems composed of enzyme, essential water and substrates/products dissolved in a solvent medium, without cells. The methodology is computationally simple, using group contribution methods for calculating constrained properties related to chemical reaction equilibrium, substrate and product solubility, water solubility, boiling points, toxicity and others. Two examples are provided, covering the screening of solvents for lipase-catalyzed transesterification of octanol and inulin with vinyl laurate. Esterification of acrylic acid with octanol is also addressed. Solvents are screened and candidates identified, confirming existing experimental results. Although the examples involve lipases, the method is quite general, so there seems to be no preclusion against application to other biocatalyst

Survival and Growth of Two \u3ci\u3eHydraecia\u3c/i\u3e Species (Noctuidae: Lepidoptera) on Eight Midwest Grass Species

Grasses play a critical role in the life cycles of both the hop vine borer (Hydraecia immanis) and potato stem borer (H. micacea), two potentially se­rious agriculture pests. Neonate larvae of both species (Noctuidae: Lepidoptera) were reared on eight selected grasses and corn for 14-18 days under greenhouse conditions to determine their survival and growth. These were quackgrass (Agropyron repens), smooth bromegrass (Bromus inermis), orchardgrass (Dactylis glomerata), large crabgrass (Digitaria sanguinalis), barnyardgrass (Echinochloa crusgalli), giant foxtail (Seteria faberii), wild prosso millet (Panicum millaceum), Johnsongrass (Sorghum halepense), and corn (Zea mays). In a separate, concurrent experiment, H. immanis and H. micacea larvae were reared on quackgrass, smooth bromegrass and orchardgrass (narrow-stemmed grasses) and sampled after 7, 10 and 14 days. H. immanis larvae generally grew more slowly and dispersed less quickly than H. micacea larvae. The fewest H. immanis and H. micacea larvae were recovered from giant foxtail. H. immanis larvae reared on quackgrass, smooth bromegrass and orchardgrass (thin-stemmed grasses) outgrew their hosts by the third instar and rapidly dispersed, particularly from quackgrass. Due to the unique internal stem-feeding behavior of these larvae the stem thickness becomes a constraining factor regarding duration of suitability to serve as a larval host. Grass feeding has tremendous significance regarding the geographic spread, local population densities, phenological damage periods, and cultural control methods such as crop rotation for these two noctuid species