This study was conducted to evaluate the effects of temperature and nematicides on endospore attachment characteristics of 2 Korean isolates of nematodeparasitic bacteria, Pasteuria penetrans. P. penetrans CJ-1 and 98-35 isolates and 3 species of root-knot nematodes in U. of Florida were used ; Meloidogyne incognita (MI), M. arenaria (MA), and M. javanica (MJ). Three nematicide levels of 2, 4, and 6 ppm were compared by treating Vydate and Nemacur in the endospore containing soils. The endospores were attached to the root-knot nematode juveniles by centrifugal method. Reproduction of the isolates was checked by observing root-knot nematode females harvested from inoculated tomato roots. 1. Among the two Korean isolates, 98-35 showed attachments to MI, MA, and MJ juveniles, but it could not reproduce in any species. CJ-1 reproduced on all the 3 tested root-knot nematode species. 2. Endospores pretreated in -14°C showed higher attachment rate than those pretreated in 4, 24, and 40℃. 3. Nemacur treatments significantly suppressed the attachment of the endospores to the juveniles, while Vydate treatment effects were negligible.

We present measurements of diffuse interstellar H2 absorption lines in the continuum spectra of 10 early-type stars. The data were observed with the Berkeley Extreme and Far-Ultraviolet Spectrometer (BEFS) of the ORFEUS telescope on board the ORFEUS-SPAS I and II space-shuttle missions in 1993 and 1996, respectively. The spectra extend from the interstellar cutoff at 912 Å to about 1200Åwith a resolution of ~ 3000 and statistical signal-to-noise ratios between 10 and 65. Adopting Doppler broadening velocities from high-resolution optical observations, we obtain the H2 column densities of rotational levels J00 = 0 through 5 for each line of sight. The kinetic temperatures derived from J" = 0 and 1 states show a small variation around the mean value of 80 K, except for the component toward HD 219188, which has a temperature of 211 K. Based on a synthetic interstellar cloud model described in our previous work, we derive the incident UV intensity IUV and the hydrogen density nH of the observed components to be -0.4 ≤ log IUV ≤ 2.2 and 6.3 ≤ nH ≤ 2500 cm-3, respectively.

Beef marbling is known as one of the most important beef-quality traits in Korea. It is likely that marbling derived from fatty acids, mainly propionate, is mediated by rumen. Recently micro-agents were studied to enhance marbling, although many parts of that were digested in rumen. Therefore, this study was conducted to screen candidate materials to effect on beef quality with in vitro ruminal incubation. The materials such as saponin, chitosan, Zn compounds (4), vitamin C sources (2), Korean herb cocktail and garlic sources (2) were added to rumen fluid to 1.25% of substrate volume at 0 and 24 h incubation time. Total gas production in intact vitamin C source increased but that in all Zn compounds decreased (P＜0.05). Total gas production in Zn sulfate compound less decreased than in other Zn sources. Propionate in Zn sulfate increased than the other candidate compounds at all incubation time (P＜0.05). Experiment two was conducted to clarified effect of additives such as vitamin C sources (2), garlic lyophilized, Korea herb cocktail and Zn sulfate were supplemented with 2.5% volume at the 0, 3, 6, 12 and 24 h incubation time. Total gas in Zn sulfate was lower than any other treatments. Propionate in garlic, herb and Zn sulfate appeared to be lower than control and vitamin C sources at all incubation time, although significant difference was not observed in total VFA among control and all treatment. This study suggested that micro-agent might be used to improve beef quality with minute level.

Predation, development, and ovipostion experiments were conducted to evaluate Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) as a potential biological control agent for tomato russet mite, Aculops lycopersici (Massee) (Acari: Eriophyidae) which is a periodic pest of greenhouse tomatoes. Results show that A. swirskii attacked all developmental stages of A. lycopersici, and had a type II functional response on the prey densities given. The predation rates of A. swirskii on A. lycopersici in the presense of alternative food sources such as pollen, thrips first instar, or whitefly eggs were recorded as 74%, 56%, and 76%, respectively of the predation rate on A. lycopersici alone. Amblyseius swirskii successfully completed their life-cycle on either A. lycopersici or cattail pollen. At 25oC, 70% RH, development time of female A. swirskii fed on A. lycopersici or on cattail pollen took 5.0 and 6.2 days, respectively. For the first 10 days after moulting to the adult stage, A. swirskii fed on A. lycopersici had higher daily oviposition rate (2.0 eggs per day) than on pollen (1.5 eggs per day). From this laboratory study, it can be concluded that A. swirskii has promising traits as a predator against A. lycopersici and that their populations can be stably maintained using alternative food such as cattail pollen. We suggest that the effectiveness of A. swirskii against A. lycopersici under field conditions deserves to be investigated.