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71.
Jeroen H. J. Ensink Christopher A. Scott Simon Brooker Sandy Cairncross 《Irrigation and Drainage Systems》2010,24(1-2):65-77
The disposal of untreated urban sewage in to open water bodies is common in most developing countries. This poses potential negative consequences to public health and agricultural sustainability. Hyderabad, one of India’s largest cities, disposes large amounts of its wastewater untreated into the Musi River, from where it is used, with the aid of irrigation weirs, for agricultural production. This paper presents a 14 month (December 2003 – January 2005) water quality survey which aimed to quantify spatial and temporal changes in key water quality parameters along a 40 km stretch of the Musi River. The survey found that river water quality improved dramatically with distance from the city; from untreated sewage in the city to irrigation water safe for use in agriculture 40 km downstream of the city. This improvement was contributed to by different treatment processes caused or aided by the irrigation weirs placed on the river. 相似文献
72.
Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest management.We used a split-plot ANOVA design to analyze differences in selected saproxylic insects(all arthropod orders and dipteran and parasitic hymenopteran families) emerging from dead wood of sites with different logging histories(horse-logged,mechanically-logged and unlogged),tree species(Populus and Picea),stage of decay(early-and late-decay stages) and posture(standing and downed logs) in the boreal forest of central Canada.No clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was apparent.Cecidomyiidae consistently emerged more from Populus than from Picea dead wood.Most of the studied saproxylic families were more abundant in late-decay than in early-decay wood.Dipterans of the Cecidomyiidae,Ceratopogonidae,Empididae,Mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead wood.In contrast,Mymaridae was most abundant in standing dead wood.Our study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions. 相似文献
73.
74.
Validation of the BioPRYN enzyme‐linked immunosorbent assay for detection of pregnancy‐specific protein‐B (PSPB) and diagnosis of pregnancy in American bison (Bison bison)
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This study assessed the accuracy of the commercial BioPRYN® ELISA for the detection of pregnancy‐specific protein‐B (PSPB) using a single blood sample to determine pregnancy status in American bison (Bison bison). A total of 49 bison cows were used in the study, and sampled at two time‐points during the gestation period, fall and spring, correlating with early‐ to mid‐term gestation (average 62.9 days post‐mating) and mid‐ to late‐term gestation (average 229.2 days post‐mating), respectively. Sensitivity of the test during early‐ to mid‐term gestation sampling period (fall) was 87.1%, while specificity was 100%; sensitivity of the test during late‐term gestation sampling period (spring) was 96.3%, while specificity remained at 100%. In total, the test showed a total sensitivity of 91.4%, specificity of 100% and total accuracy of 93.8%, similar to domestic cattle. Use of the single‐sample BioPRYN® ELISA in American Bison for pregnancy diagnosis is economical and practical, minimizing animal handling time, frequency and subsequent stress while providing accurate results for pregnancy diagnosis at 62 days post‐mating. This method should be considered over more traditional pregnancy diagnosis methods for use in managed bison herds. 相似文献
75.
In March of 2012, following a robust activist campaign, Arysta LifeScience withdrew the soil fumigant methyl iodide from the US market, just a little over a year after it had finally been registered for use in California. As a major part of the campaign against registration of the chemical, over 53,000 people, ostensibly acting as citizens rather than consumers, wrote public comments contesting the use of the chemical for its high toxicity. Although these comments had marginal impact on the outcome of the case, these comments are of interest for what they say about public action at a time when efforts to address food and agricultural issues have been dominated by “voting with your fork.” Based on a qualitative textual analysis of approximately 3500 representative comments made available to us, we show that many of those taking action did not abandon consumer subjectivities associated with neoliberal governmentality. By threatening “personal boycotts,” some were acting in their capacity as individual consumers; in invoking their own and their children’s health many more were also acting on behalf of consumers, despite that the chemical in question is applied before strawberries are planted and thus leaves no residues. The emphasis that letter writers gave to their own bodies reinforces the idea that some bodies count more than others and thus reveals a biopolitical sorting. Having consumer lives matter is consequential in light of evidence that consumer concern about pesticides has historically led to formulations and regulations more protective of consumers than workers and neighbors. 相似文献
76.
David Curwen Pete Weingartner Ronald Knight Therese M. Work Hugh J. Murphy Steven B. Johnson Richard Zink Leigh Morrow A. R. Mosley Rod Davidson Thoms Owings Don Halseth John Bamberg John C. Wallace Stephen Love Don Halseth Elmer E. Ewing LaMont Anderson Neil Gudmestad Oscar Malamud Jane Seabrook Robert E. Thornton Ronald Voss A. J. Mosley 《American Journal of Potato Research》1991,68(12):861-902
77.
Stephen L. Love Asunta L. Thompson Timothy P. Baker Dennis L. Corsini 《American Journal of Potato Research》1992,69(5):299-307
Ten ‘Russet Burbank’ potato clones collected from various geographical regions of the United States and Canada were evaluated for plant and agronomic characteristics for two years at Aberdeen, Idaho. Clonal differences were detected for emergence time, stem number per hill, expression of Verticillium symptoms, some measures of yield, and percentage of tubers with hollow heart. Eight of the ten clones were quite similar. Differences were slight or found only in a few characteristics. One clone, collected from northern Idaho, was similar to the homogenous eight clones in all respects except yield, which was probably due to chronic PVX infection throughout the trial period. Another clone, collected from New Brunswick, was distinct from all other clones and was markedly inferior with respect to many of the characteristics measured when grown in Idaho. 相似文献
78.
Genetic improvement has been the principle contributor to productivity growth in almost all field crops. The Pacific Northwest (PNW) had the highest rate of potato yield growth combined with the least amount of varietal change in any specialized major field crop-producing region in North America. A coordinated potato variety development program, jointly funded by the USDA, the three land grant universities, and the potato industry in the PNW, was established in 1984. The program developed 17 new potato varieties during the 1989–2001 period, two of them are emerging as successful processing varieties. Ranger Russet, released in 1991, and Umatilla Russet, released in 1998, possess several desired quality and production traits. The most important of these traits is 20% higher processing yield than present varieties. Since their release, there has been significant increase in the percentage of potato area planted with these new varieties. The weighted average adoption rate of these new varieties in the PNW in 2000 was about 16% of the area planted with potato. This represents 32.5% of Washington’s potato acreage, 14.3% of Oregon’s potato acreage, and 9.0% of Idaho’s potato acreage. The benefit to investments in the PNW Potato Variety Development Program attributed only to the flow of benefits from the adoption of Ranger Russet and Umatilla Russet is estimated at over $104.3 million in year 2000 and projected to increase to $213.595 million in year 2014 and thereafter. Rate of return to investment is estimated at 35%. 相似文献
79.
Effect of planting depth and hilling practices on total, U.S. No. 1, and field greening tuber yields
Previous research suggests that field greening of potato tubers can be minimized by planting seedpieces at an appropriate depth along with sufficient hilling to minimize exposure to sunlight. The appropriate planting depth and hilling practices to minimize field tuber greening have not been determined for newer cultivars. Two separate studies, each conducted for three years, are reported here. The first measured the effect of seedpiece planting depth on the yield, quality, and field greening tuber yield of ‘Russet Burbank’, ‘Frontier Russet’, and ‘Shepody’ potatoes. Seedpieces were handplanted in pre-formed hills at 8, 15, or 23 cm measured from the top of the seedpiece to the top of the hill. Planting at 23 cm resulted in significantly lower total yield compared with the 8- and 15-cm depths for Russet Burbank and Frontier Russet, but planting depth did not affect total yield of Shepody. U.S. No. 1 yield of Russet Burbank was not affected by planting depth, but U.S. No. 1 yield of Frontier Russet was significantly less at the 23-cm depth. For Shepody, the 8-cm depth caused a significant reduction in U.S. No. 1 yield compared with the 15-cm depth. Field greening tuber yield of Russet Burbank was significantly less at the 23-cm planting depth compared to 8 cm. For Frontier Russet and Shepody, planting at 15 or 23 cm resulted in significantly less field tuber greening compared to the 8-cm depth. The second experiment examined the effects of planting depth and hilling practices on yield, quality, and field tuber greening of Russet Burbank and Gem Russet potatoes. Six planting depth and hilling treatment combinations were used. Seedpieces were planted at a depth of either 8 or 15 cm, then hilled to either 15 or 23 cm at emergence or after plants had formed a rosette of leaves approximately 10 cm in diameter (post-emergence hilling). At-emergence hilling treatments had no effect on total or U.S. No. 1 yields of Russet Burbank compared with the 15-cm planting depth, non-hilled control. However, all post-emergence hilling treatments significantly reduced Russet Burbank total and U.S. No. 1 yields. Planting Russet Burbank at 8 cm and hilling to 23 cm at emergence, or planting at 8 or 15 cm and hilling to 23 cm post-emergence reduced field tuber greening of Russet Burbank. The effects of planting depth and hilling on Gem Russet total and U.S. No. 1 yields were less definitive than for Russet Burbank, and no treatments significantly reduced field tuber greening yield compared with the control. 相似文献
80.
R. G. Novy D. L. Corsini S. L. Love J. J. Pavek A. R. Mosley S. R. James D. C. Hane C. C. Shock K. A. Rykbost C. R. Brown R. E. Thornton 《American Journal of Potato Research》2003,80(5):295-301
‘Alturas’, a late-maturing, high-yielding, russet potato cultivar with high tuber specific gravity, was released in 2002 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington. Originally selected for dehydration processing, its cold-sweetening resistance also makes it suitable for processing out of storage into french fries and other frozen potato products. Culinary quality is high, with larger tubers suitable for fresh market if heavily russeted skin is not essential. Alturas consistently produced greater total and U.S. No. 1 yields than ‘Russet Burbank’ and ‘Ranger Russet’ in southern Idaho trials. Across other western trial sites, total yields of Alturas have on average been 29% and 14% greater than Russet Burbank and Ranger Russet, respectively. Alturas is resistant to Verticillium wilt (Verticillium dahliae) and early blight (Alternaria solani). Compared with Russet Burbank and Ranger Russet, Alturas is less susceptible to corky ringspot and foliar and tuber infection by late blight (Phytophthora infestans). It also is less susceptible to tuber net necrosis and Fusarium dry rot than Russet Burbank, and is more resistant to common scab (Streptomyces scabies) than Ranger Russet. However, Alturas is more susceptible to infection by PVY and PVX than Ranger Russet. Total nitrogen application recommendations for Alturas are approximately 40% less than those for Russet Burbank. Alturas requires 15% to 20% more water during the growing season than does Russet Bur-bank. 相似文献