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As part of a comprehensive study to survey predators associated with hemlock woolly adelgid, Adelges tsugae Annand, 1928 in the Pacific Northwest (PNW), U.S.A. (Kohler et al. 2008), predators of balsam woolly adelgid, Adelges piceae (Ratzeburg, 1844) and Cooley spruce gall adelgid, Adelges cooleyi (Gillette, 1907) (all Hemiptera: Adelgidae) were sampled on nine dates from June 2005 to October 2006 on a small number of trees. Samples were collected every 6–8 weeks. Predators were collected from two A. piceae infested grand fir, Abies grandis (Douglas ex David Don) Lindley, and one A. cooleyi infested Engelmann spruce, Piceae engelmanii Parry ex Engelmann, on the Oregon State University campus in Corvallis, Oregon, and two A. cooleyi infested Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco (all Pinaceae). One Douglas-fir was an ornamental tree in Corvallis, Oregon and the other was in a seed orchard on Whidbey Island, Washington. Adelges cooleyi predators were collected by striking an infested branch four times over a plastic tub with an area of 0.16 m2. Adelges piceae predators were collected by brushing adelgid wool on the bole of infested trees with a 2-inch wide paintbrush over a beat sheet. Predators were collected from the tub and beat sheet with an aspirator. Adult insects were killed in a sealed 9-dram plastic vial containing a small piece of Hot Shot No-Pest Insecticide Strip (Spectrum Brands Inc., Atlanta, Georgia). Immature insects were killed in KAAD mixture (10 parts 95% ethanol, 1 part kerosene, 2 parts glacial acetic acid, and 1 part dioxane) and preserved in 70% ethanol (Borrer et al. 1989). Adult specimens were identifi ed either by taxonomic specialists or by comparison to previously identified museum specimens. Voucher specimens were deposited in the Oregon State Arthropod Collection, Department of Zoology, Oregon State University, Corvallis, Oregon.

Two tomato inbred backcross line (IBL) populations, derived from crosses between aphid-susceptible Lycopersicon esculentum Mill. 'Peto 95-43' X resistant wild L. pennellii Corr (D'arcy) accession LA716, and Peto 95-43 X resistant wild L. hirsutum f. glabratum Mull accession LA407, were evaluated in replicated field experiments for resistance to potato aphid, Macrosiphum euphorbiae (Thomas), and green peach aphid, Myzus persicae (Sulzer). Aphid infestation scores for each IBL and control (LA716, LA407, Peto 95-43, and susceptible 'Alta') plot were recorded weekly for 5 and 9 wk during the summers of 2000 and 2001, respectively. Aphid infestation scores from leaflets were used to calculate area under the infestation pressure curve (AUIPC), a measure of aphid infestation throughout the growing season, for each IBL and control. Score AUIPC was highly correlated with actual aphid count AUIPC, indicating that scores accurately reflected aphid infestation. Score AUIPC was also highly correlated across both years (2000 and 2001) and locations. Low score AUIPC was significantly correlated with larger plant size and sprawling, indeterminate plant growth habit. Seven IBLs, LA716, and LA407 were significantly more resistant to aphids (lower score AUIPC) than susceptible parent Peto 95-43 in both years. Two IBLs, 1034 and 1051, were not significantly different from resistant LA407 for score AUIPC in both years. The seven aphid-resistant IBLs identified here can be useful as donor parent material for resistance breeding efforts in cultivated tomato.

Two tomato inbred backcross line (IBL) populations, derived from crosses between aphid-susceptible Lycopersicon esculentum Mill. 'Peto 95-43' X resistant wild L. pennellii Corr (D'arcy) accession LA716, and Peto 95-43 X resistant wild L. hirsutum f. glabratum Mull accession LA407, were evaluated in replicated field experiments for resistance to potato aphid, Macrosiphum euphorbiae (Thomas), and green peach aphid, Myzus persicae (Sulzer). Aphid infestation scores for each IBL and control (LA716, LA407, Peto 95-43, and susceptible 'Alta') plot were recorded weekly for 5 and 9 wk during the summers of 2000 and 2001, respectively. Aphid infestation scores from leaflets were used to calculate area under the infestation pressure curve (AUIPC), a measure of aphid infestation throughout the growing season, for each IBL and control. Score AUIPC was highly correlated with actual aphid count AUIPC, indicating that scores accurately reflected aphid infestation. Score AUIPC was also highly correlated across both years (2000 and 2001) and locations. Low score AUIPC was significantly correlated with larger plant size and sprawling, indeterminate plant growth habit. Seven IBLs, LA716, and LA407 were significantly more resistant to aphids (lower score AUIPC) than susceptible parent Peto 95-43 in both years. Two IBLs, 1034 and 1051, were not significantly different from resistant LA407 for score AUIPC in both years. The seven aphid-resistant IBLs identified here can be useful as donor parent material for resistance breeding efforts in cultivated tomato.

Many plants of tropical or subtropical origin, such as tomato, suffer damage under chilling temperatures (under 10 degrees C but above 0 degrees C). An earlier study identified several quantitative trait loci (QTLs) for shoot turgor maintenance (stm) under root chilling in an interspecific backcross population derived from crossing chilling-susceptible cultivated tomato (Lycopersicon esculentum) and chilling-tolerant wild L. hirsutum. The QTL with the greatest phenotypic effect on stm was located in a 28 cM region on chromosome 9 (designated stm 9), and enhanced chilling-tolerance was conferred by the presence of the Lycopersicon hirsutum allele at this QTL. Here, near-isogenic lines (NILs) were used to verify the effect of stm 9, and recombinant sub-NILs were used to fine map its position. Replicated experiments were performed with NILs and sub-NILs in a refrigerated hydroponic tank in the greenhouse. Sub-NIL data was analyzed using least square means separations, marker-genotype mean t-tests, and composite interval mapping. A dominant QTL controlling shoot turgor maintenance under root chilling was confirmed on chromosome 9 using both NILs and sub-NILs. Furthermore, sub-NILs permitted localization of stm 9 to a 2.7 cM interval within the original 28 cM QTL region. If the presence of the L. hirsutum allele at stm 9 also confers chilling-tolerance in L. esculentum plants grown under field conditions, it has the potential to expand the geographic areas in which cultivated tomato can be grown for commercial production.

Groups of rats were raised from weaning under normal animal colony conditions and conditions of reduced sensory stimulation. In a shuttle box groups of 5, 2, and 2 showed acquisition for mild shock proportional to degree of deprivation ( P < .02). In a second experiment 16 deprived animals preferred shock more than did 14 nondeprived animals ( P < .01). Nondeprived rats preferred shock to no shock ( P < .01). The results are interpreted as effects of arousal and satiation.

Groups of 6, 6, and 7 IR and INR rats were adapted to test chambers in total darkness for one week, one month, and two months and habituated to operant bar apparatus for 70, 300, and 600 sessions then tested for operant level, shock contingent bar press, and extinction in 150, 150, and 350 sessions, all of 16–2/3 min. each. Shock proved positively reinforcing and cumulative shock durations were functions of shock intensity and animal reactivity (p