52-Week oral gavage chronic toxicity study with ubiquinone in rats with a 4-week recovery

Potential ubiquinone (CoQ10; a natural fermentation product) toxicity was assessed in rats administered CoQ(10) by oral gavage for 1 year at 100, 300, 600, and 1200 mg/(kg day). No adverse changes in mortality, clinical signs, body weight, food consumption, or clinical pathology results occurred. CoQ(10) had elimination half-lives ranging from 10.7 to 15.2 h. At 1200 mg/(kg day), a high incidence of orange, granular, lumenal exudate in nasal turbinates occurred; microscopically, findings similar to those in the turbinates were occasionally observed in small granulomas within lung alveoli. A dose-related increased incidence of vacuolated macrophages (mesenteric lymph nodes) and vacuolated hepatic periportal cells was noted. Neither were associated with tissue damage or organ dysfunction, so they were not considered to be adverse. The nasal turbinate and lung findings were probably secondary to incidental exposure to crystallized test material. Overall, CoQ(10) was well tolerated by male and female rats at dose levels up to 1200 mg/(kg day).     

Determination of halogenated phenols in raw and potable water by selected ion gas chromatography-mass spectrometry

Pentafluorobenzylation and in situ acetylation are compared in the determination of phenol and halogenated phenols in water samples. The latter technique is considered superior to the former for determining phenols at the ng/L level because of less background interference and better recoveries (80% or better except for pentachlorophenol and trichloroguaiacol which had recoveries of about 60%). Further evaluation of the in situ technique by electron capture gas chromatography and gas chromatography-mass spectrometry shows that the latter, in the selected ion monitoring mode, is more suitable because, unlike GC-ECD, it can confirm and quantitate all phenols. In particular, GC-ECD could not detect even high levels of phenol and the monohalogenated phenols. Phenols at 5-473 ng/L were detected in some Canadian drinking water supplies by the in situ acetylation technique combined with GC-MS.     

STUDIES ON THE ROOT DEVELOPMENT OF HERBAGE PLANTS

Various methods of root sampling are reviewed and discussed in relation to the type of information required. The root sampling techniques at the Grassland Research Institute are described and examples of sampling errors are given. Details of a root washing machine are given.     

Introgression and stabilization oferwinia tuber soft rot resistance into potato after somatic hybridization ofsolanum tuberosum ands. brevidens

Resistance to potato tuber soft rot caused byErwinia carotovora was transferred fromSolanum brevidens to the cultivated potato over the course of four backcross generations originating from a somatic hybrid. Soft rot reactions were determined via a tuber plug inoculation method developed during the course of these experiments. Soft rot resistance was highest in the somatic hybrid (only ca. 20% of tubers and plugs showed evidence of severe rotting) and lowest among progeny of control potato x potato crosses (ca. 80% of tuber plugs showed severe rot). Backcross generations involving somatic hybrids were intermediate in their reaction, and resistance stabilized to about 60% of tuber plugs showing severe rot in the BC₂ through the BC₄. Reciprocal crosses showed no difference in the inheritance of soft rot resistance, indicating that neitherS. brevidens norS. tuberosum donor cytoplasm had a significant effect on the expression of resistance. Crosses between BC₃ siblings where noS. brevidens genetic markers were detected but resistance was segregating demonstrated a dosage effect for soft rot resistance. We conclude that introgression of soft rot resistance has occurred and that at least one locus responsible for resistance inS. brevidens now resides in theS. tuberosum genome.     

Leaf mineral nutrient concentrations or media pH affect Georgia Jet sweetpotato transplant number,length, and weight 1

The results of four experiments were combined to determine the relationships between leaf mineral nutrients or media pH and sweetpotato transplant production. The relative number of transplants and the relative mean transplant lengths or weights were determined by comparing the values obtained with unamended aged pine sawdust, a traditional medium. These values were regressed against leaf mineral concentrations and media pH. There was no relationship between relative transplant production and leaf nitrogen (N), potassium (K), or manganese (Mn) concentrations. Compared to sufficiency ranges for nearly mature sweetpotatoes, concentrations of N and K were low and Mn was sufficient. An upper value of 1210 mg/L leaf iron (Fe) was obtained for relative mean transplant weight, but concentrations of this mineral were not associated with relative transplant numbers or relative mean transplant lengths. Leaf calcium (Ca) and magnesium (Mg) concentrations were related to all three transplant characteristics directly, or indirectly through possible effects on leaf phosphorus (P) concentration or media pH. Compared to the established sufficiency ranges for nearly mature sweetpotato plants, Ca and Mg concentrations were low, P and Fe concentrations were sufficient, and zinc (Zn) concentrations were high.     

Review of The Chinese Medicinal Herb Farm

Collaborative ventures between industry and professional association represent a strategy to maximize resources for a mutual goal. As a cooperative venture, The American Dietetic Association co-sponsored with Kraft General Foods, Inc. and The Good Housekeeping Institute a survey on American's diet and nutrition habits. The survey findings focused on consumer's behaviors, attitudes, knowledge and obstacles toward diet and nutrition. The results from the survey are being used to create and expand nutrition education campaings to the public.     

An aboveground–belowground assessment of ecosystem properties associated with exotic annual brome invasion

Exotic annual brome invasion has been well studied in western North American rangelands, particularly for Bromus tectorum L. invasion in sagebrush (Artemisia tridentata) grasslands. We examined both aboveground and belowground properties in native sagebrush grassland and adjacent areas dominated by exotic annual bromes (B. tectorum L. and Bromus japonicus Thunb.) to better understand the fundamental ecological differences between native and invaded areas. Field sites were located in north central Wyoming, USA, and plots were established in areas that had been historically subject to wildfire and either (1) recolonized by native sagebrush grassland vegetation or (2) invaded by exotic annual bromes. We employed measures of vegetation community structure as well as soil physical, chemical, and microbiological properties. Plots with greater than 20 % exotic annual brome cover had significantly less cover of all native vegetation functional groups resulting in lower richness and evenness than native plots. Invaded plots also had low diversity plant communities that were continuous and uniform across space. Soils beneath invaded plant communities had higher infiltration rates, higher levels of total nitrogen, and a lower C/N ratio than the native soils. Invaded soils also had 90–96 % lower abundance of all soil microbial groups measured by phospholipid fatty acid. We conclude that areas dominated by exotic annual bromes display different aboveground and belowground properties compared to the native community, and these changes possibly include spatial and temporal shifts in soil resources and organic matter processing.     

Zinc nutrition affects alfalfa responses to water stress and excessive moisture

The interactive effect of applied zinc (Zn) and soil moisture on early vegetative growth of three alfalfa (lucerne) (Medicago sativa L.) varieties was investigated in a sand‐culture pot experiment to test whether there is link between Zn nutrition and soil moisture stress or excessive moisture tolerance in alfalfa plants. Three varieties (Sceptre, Pioneer L 69, and Hunterfield) with differential Zn efficiency (ability of a variety to grow and yield well in a Zn deficient soil is called a Zn‐efficient variety) were grown at two Zn levels (low Zn supply: 0.05 mg Zn kg^‐1 of soil, adequate Zn supply: 2.0 mg Zn kg^‐1 of soil) and three levels of soil moisture (soil moisture stress: 3% soil moisture on soil dry weight basis; adequate soil moisture: 12% soil moisture on soil dry weight basis; excessive soil moisture: 18% soil moisture on soil dry weight basis) in a Zn deficient (DTPA Zn: 0.06 mg kg^‐1 soil) siliceous sand. Zinc treatments were applied at planting, while soil moisture treatments were applied three weeks after planting and continued for two weeks. Plants were grown in pots under controlled temperature conditions (20°C, 12 h day length; 15°C, 12 h night cycle) in a glasshouse. Plants grown at low Zn supply developed Zn deficiency symptoms, and there was a severe solute leakage from the leaves of Zn‐deficient plants. Adequate Zn supply significantly enhanced the leaf area, leaf to stem ratio, biomass production of shoots, and roots, succulence of plants and Zn concentration in leaves. At low Zn supply, soil moisture stress and excessive moisture treatments significantly depressed the shoot dry matter, leaf area and leaf to stem ratio of alfalfa plants, while there was little impact of soil moisture treatments when supplied Zn concentration was high. The detrimental effects of soil moisture stress and excessive soil moisture under low Zn supply were less pronounced in Sceptre, a Zn‐efficient alfalfa variety compared with Hunterfield, a Zn‐inefficient variety. Results suggest that the ability of alfalfa plants to cope with water stress and excessive soil moisture during early vegetative stage was enhanced with adequate Zn nutrition.     

Can spinosad be effective for the integrated management of Anastrepha ludens (Tephritidae) in soil and fallen fruit,and be compatible with the parasitoid Diachasmimorpha longicaudata (Braconidae)?

Phytoparasitica - Tephritid fruit flies are susceptible to insecticide treatments when leaving infested fruit to pupate in the soil and when emerging as adults. Laboratory experiments involved...