Effects of squash leaf trichome exudates and honey on adult feeding, survival, and fecundity of the squash bug (Heteroptera: Coreidae) egg parasitoid Gryon pennsylvanicum (Hymenoptera: Scelionidae)

Citation: Olson, D., & Nechols, J. Effects of Squash Leaf Trichome Exudates and Honey on Adult Feeding, Survival, and Fecundity of the Squash Bug (Heteroptera: Coreidae) Egg Parasitoid Gryon pennsylvanicum (Hymenoptera: Scelionidae). Environmental Entomology, 24(2), 454-458. https://doi.org/10.1093/ee/24.2.454A laboratory experiment was conducted to determine whether leaf exudates could be used as a source of adult nutrition for the squash bug, Auasa tristis (De Geer), egg parasitoid, Gryon pennsylvanicum (Ashmead), and to compare adult and progeny fitness traits when female Wasps were provided with squash leaves, a standard honey diet, a combination of leaves and honey, or water only Results showed that fecundity, progeny developmental rates, and progeny survival did not differ significantly when females were exposed to different dietary sources. Adult longevity was shorter on squash leaves without honey than on leaves with honey or the honey-only diet. However, reproductive fitness was not reduced because oviposition had been completed before death of the adult females. When only water was provided, parasitoid females lived only a few days. Observations showed that squash leaves have two kinds of trichomes (hair-like and peg-like), both of which produce droplets that are fed on by both sexes of G. pennsylvanicum. Nutrient analyses revealed that exudates from the hair-like trichomes are composed predominantly of monosaccharides (mainly glucose and galactose), and that the peg-like trichomes produce glucose and some protein. Thus, these trichomes appear to serve as extrafloral nectaries and may provide an important energy source for augmentatively released G. pennsylvanicum

Provisions and Potential Impacts of the Average Crop Revenue Election (ACRE) Program

Replaced with revised version of paper 11/24/08.Agricultural and Food Policy, Crop Production/Industries,

Estimates of Minnesota Farm-Level Crop Commodity Payments under New House Framework

The objective of this study is to compare commodity payments under current Federal farm policy with the previous Senate and Administration proposals and the recently released “2008 Farm Bill Conference: House Agriculture Committee-Developed Concept for a Farm Bill Spending Framework.” Projections of crop revenue and government payments are made using historical yield data for each example farm, the county, and the nation; historical price data; and statistical distributions and relationships of these yields and prices. Using 2007 FAPRI price projections (which are closer to the prices expected in the next few years when a new farm bill will be in force), expected Total Government Payments (TGP) are almost entirely attributed to the fixed direct payments under all these proposals. Since commodity prices are so far above their “target levels” the possibility of a counter cyclical price or revenue payment or a loan deficiency payment is highly unlikely. TGP under the alternative policies follows a similar pattern on the example corn and soybean farms and a slightly different but fairly consistent pattern for the example wheat and soybean farms. For the corn and soybean example farms in southern Minnesota, the HB-RCCP and USDA proposals generate very similar levels of TGPs compared to current policy. HB-RCCP provides a slightly higher expected TGP than CP for all example farms except for one and higher TGP than USDA for all farms. ACR is estimated to provide lower TGP for all example corn and soybean farms. For the example wheat and soybean farms in northwest Minnesota, the results are mixed. Compared to the other three proposals, ACR provides higher TGP for 2 of the 6 example farms. Each of the proposals does reduce risk as measured by CV. We note ACR is not quite as efficient at risk reduction except for two wheat/soybean farms in northwest Minnesota.Farm Management,

New GOES satellite synchronized time code generation

The TRAK Systems' GOES Satellite Synchronized Time Code Generator is described. TRAK Systems has developed this timing instrument to supply improved accuracy over most existing GOES receiver clocks. A classical time code generator is integrated with a GOES receiver

Alternative Farm Bills: Impacts on Minnesota Farms

With the current federal farm bill set to expire at the end of September this year, many proposals have been made to redesign the next bill. The objectives of this study are to compare the current policy with major proposed alternatives and estimate the potential payments of farmers under each of the alternatives. The alternative policies are compared in two ways. First a historical comparison of crop revenue and estimated government payments for individual farms are made under each proposal from 2002-2005. In a second comparison, projections of crop revenue and government payments are made using historical yields for each farm, county, and nation; historical price data; statistical distributions of the yields and prices including averages, standard deviations, and correlations; and each proposal's rules for calculating payments. For yields, deviations from the yield trend are used. In three of the four years and on average, the American Soybean Association (ASA) proposal has higher payments and thus higher total gross revenue compared to current policy and the other three proposals. Since the ASA proposal raises both loan rates and target prices, the higher payments should be expected. The proposed USDA policy is estimated to have a slightly higher average government payment and total gross revenue compared to current policy, but it is not higher than current policy in each year. Lower total payments under the National Corn Growers Association (NCGA) proposal are due to higher than average revenues during 2002-05. The revenue insurance proposal does not create any indemnity payments in 2002-05 again due to the higher revenues in these years. Projections of potential revenue also show the ASA proposal to have higher estimated payments. Average government payments are estimated to be slightly higher under current policy compared to USDA's and NCGA's proposals. Since federal budget concerns may not allow the higher payments under the ASA proposal, the choice between the USDA and NCGA proposal may hinge on the level of administrative costs which would appear to be lower with the USDA proposal since it is based on one national estimate of revenue versus many county and individual calculations under the NCGA proposal. The potential use of multi-commodity revenue insurance will hinge on either the ability to provide additional support in fixed direct payments and green payments and larger federal budget concerns.Agricultural and Food Policy,

The DOE/NASA wind turbine data acquisition system. Part 3: Unattended power performance monitor

Software documentation, operational procedures, and diagnostic instructions for development version of an unattended wind turbine performance monitoring system is provided. Designed to be used for off line intelligent data acquisition in conjunction with the central host computer

Aerodynamic characteristics of the 40- by 80/80- by 120-foot wind tunnel at NASA Ames Research Center

The design and testing of vane sets and air-exchange inlet for the 40 x 80/80 x 120-ft wind tunnel at NASA Ames are reported. Boundary-layer analysis and 2D and 3D inviscid panel codes are employed in computer models of the system, and a 1/10-scale 2D facility and a 1/50-scale 3D model of the entire wind tunnel are used in experimental testing of the vane sets. The results are presented in graphs, photographs, drawings, and diagrams are discussed. Generally good agreement is found between the predicted and measured performance

Imperfect identity

Questions of identity over time are often hard to answer. A long tradition has it that such questions are somehow soft: they have no unique, determinate answer, and disagreements about them are merely verbal. I argue that this claim is not the truism it is taken to be. Depending on how it is understood, it turns out either to be false or to presuppose a highly contentious metaphysical claim

Identification of novel chondroitin proteoglycans in Caenorhabditis elegans: embryonic cell division depends on CPG-1 and CPG-2.

Vertebrates produce multiple chondroitin sulfate proteoglycans that play important roles in development and tissue mechanics. In the nematode Caenorhabditis elegans, the chondroitin chains lack sulfate but nevertheless play essential roles in embryonic development and vulval morphogenesis. However, assignment of these functions to specific proteoglycans has been limited by the lack of identified core proteins. We used a combination of biochemical purification, Western blotting, and mass spectrometry to identify nine C. elegans chondroitin proteoglycan core proteins, none of which have homologues in vertebrates or other invertebrates such as Drosophila melanogaster or Hydra vulgaris. CPG-1/CEJ-1 and CPG-2 are expressed during embryonic development and bind chitin, suggesting a structural role in the egg. RNA interference (RNAi) depletion of individual CPGs had no effect on embryonic viability, but simultaneous depletion of CPG-1/CEJ-1 and CPG-2 resulted in multinucleated single-cell embryos. This embryonic lethality phenocopies RNAi depletion of the SQV-5 chondroitin synthase, suggesting that chondroitin chains on these two proteoglycans are required for cytokinesis