Preliminary Evaluation of a Dodder Anthracnose Fungus from China as a Mycoherbicide for Dodder Control in the US

Dodder (Cuscuta spp.) is a noxious, parasitic, annual weed throughout most of the United States. A fungus used to control it in China was imported under permit for studies with U.S. dodder species in containment. The fungus, Colletotrichum gloeosporioides, sporulated on liquid and solid media at room temperature. Conidia from 7-12 day old cultures were diluted to 3.5 to 7 X 16⁶ spores ml^-1 for host range inoculations. Germination on water agar at 24 hrs was higher at 28 than 30 or 24 C. Inoculated plants were exposed to dew periods of 12-1 4 hrs at 24 or 28 C, then transferred to growth chambers with 1 2-hr photoperiods at constant temperatures of 24, 28, and 32C. Dodder species were severely diseased but rarely killed. Symptoms were most severe on native collections of Cuscuta campestris after 4 to 5 days incubation when this species on periwinkle seedlings was inoculated with 3.5 to 7 X 10⁵ spores ml^-1 . Cuscuta cuspidata, C. pentagona, and C. campestris from a California seedlot were also tested under optimum conditions for disease. The C. campestris from California was the most susceptible. Inoculation of 16 species in eight plant families revealed no other host except sweet potato which developed a necrotic fleck. This research indicates a need for strain improvement prior to field tests

Wood Frog (Rana sylvatica) Use of Wildlife Ponds in Northcentral Arkansas

Forty-one wildlife ponds were monitored between 1988 and 1992 for breeding use by wood frogs (Rana sylvatica). Data were collected on egg deposition and pond characteristics. Breeding activity and characteristics were similar to that reported in other portions of the range of the wood frog. We also monitored 15 newly-constructed ponds to determine chronological breeding patterns. Data collected for each site indicated a significant increase (P\u3c 0.05) in the number of egg masses deposited in ponds as they age from 1-3 years during our study period. Increased chronological use of newly-constructed ponds may be due to localized population increase resulting from greater availability of breeding habita

Estimating Individual Feed Intake of Group-Fed Steers by Modified Weighing Design

An experimental design for estimation of feed intake of individual animals fed in pairs or groups is discussed. Procedures are given to compute 95% confidence intervals of estimates. The accuracy a researcher needs for experimentation will suggest whether he can successfully utilize this procedure for estimation of feed intake of individual animals. Disadvantages of the design appear to be related to numbers of replicates required when large numbers of animals are involved. © 1978, American Dairy Science Association. All rights reserved

Oceanic tide maps and spherical harmonic coefficients from Geosat altimetry

Maps and tables for the global ocean tides, 69 degree N to 68 degree S, derived from two years of Geosat altimetry are presented. Global maps of local and Greenwich admittance of the (altimetric) ocean tide, and maps of amplitude and Greenwich phase lag of the ocean tide are shown for M(sub 2), S(sub 2), N(sub 2), O(sub 1), and K(sub 1). Larger scale maps of amplitude and phases are also shown for regional areas of special interest. Spherical harmonic coefficients of the ocean tide through degree and order 8 are tabulated for the six major constituents