Agriculture. What next for agriculture after Durban?     

Beddington JR  Asaduzzaman M  Clark ME  Fernández Bremauntz A  Guillou MD  Howlett DJ  Jahn MM  Lin E  Mamo T  Negra C  Nobre CA  Scholes RJ  Van Bo N  Wakhungu J 《Science (New York, N.Y.)》2012,335(6066):289-290

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DIMETHOATE CONTROLLING PIGEON DAMAGE AND DIAMOND-BACK MOTH     

S. W. H. Rolfe 《Plant pathology》1964,13(4):150-150

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Genetic Variation and Association Mapping of Protein Concentration in Brown Rice Using a Diverse Rice Germplasm Collection     

Rolfe J. Bryant  Aaron K. Jackson  Kathleen M. Yeater  Wengui G. Yan  Anna M. McClung  Robert G. Fjellstrom 《Cereal Chemistry》2013,90(5):445-452

Protein is the second most abundant constituent in the rice grain next to starch. Association analysis for protein concentration in brown rice was performed using a “mini‐core” collection, which represents the germplasm diversity found in the USDA rice world collection. Protein concentration was determined in replicated trials conducted in two southern U.S. locations, and association mapping was performed by using 157 genomewide DNA markers. Protein concentration ranged from 5.4 to 11.9% among the 202 accessions. Protein variation owing to accession and accession × location interaction were highly significant. Ample variation was seen within each subpopulation by ancestry, as well as within the 14 geographic regions where the accessions originated. Accessions from Eastern Europe had the highest level of protein. Ten markers on eight chromosomes were significantly associated with protein concentration. Five of these markers occurred near known protein precursor genes or quantitative trait loci, and the other five markers were novel for the association with protein concentration in rice. The germplasm and genetic markers identified in this study will assist breeders in developing cultivars tailored for applications requiring specific protein concentration in the rice grain. The research results contribute to the potential discovery of novel rice storage protein pathways in the endosperm.  相似文献   

Privileging the sub-sector: critical sub-sectors and sectoral relationships in forest policy-making     

Jeremy Rayner  Michael Howlett  Jeremy Wilson  Benjamin Cashore  George Hoberg   《Forest Policy and Economics》2001,2(3-4)

Policy analysis has usually been organized around the concept of the policy sector, which has served as the fundamental unit for analyzing policy change. The emergence of well-defined and institutionalized issue subsectors, however, has called the utility of a purely sectoral analysis of policy dynamics into question. Utilizing evidence from a case study of forest policy development in British Columbia, Canada, in the 1990s, this article suggests that understanding policy change in complex sectors such as forestry requires a more nuanced conceptualization and analysis of sector–subsectoral relationships than exists in the present literature. The article develops the notion of critical subsectors, capable of blocking or enabling overall levels and directions of sectoral policy change, as an essential tool required to understand policy dynamics.  相似文献   

Late Quaternary environmental change inferred from phytoliths and other soil-related proxies: Case studies from the central and southern Great Plains,USA     

Carlos E. Cordova  William C. Johnson  Rolfe D. Mandel  Michael W. Palmer 《CATENA》2011

This study investigates stable carbon isotopes (δ¹³C), opal phytolith assemblages, burnt phytoliths, microscopic charcoal and Sporormiella spores from modern soils and paleosols in Kansas and Oklahoma. Grass and dicot phytoliths in combination with δ¹³C are used as proxies for reconstructing the structure of grasslands and woodlands. Burnt grass phytoliths and microscopic charcoal are evaluated as proxies for reconstructing paleofire incidence. Concentrations of the fungal spore Sporormiella are used as a proxy for assessing large herbivore activity. These proxies were tested on various modern grassland communities of the central and southern Great Plains, including areas with bison, cattle, and small herbivores, and areas under different fire frequencies.  相似文献   

Control of pancreas and liver gene expression by HNF transcription factors     

Odom DT  Zizlsperger N  Gordon DB  Bell GW  Rinaldi NJ  Murray HL  Volkert TL  Schreiber J  Rolfe PA  Gifford DK  Fraenkel E  Bell GI  Young RA 《Science (New York, N.Y.)》2004,303(5662):1378-1381

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Superconductivity of alpha uranium     

Howlett BW  Matthias BT 《Science (New York, N.Y.)》1966,154(3748):542-543

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水分胁迫对番茄幼苗转化酶表达及糖代谢的影响   总被引：24，自引：1，他引：24  

程智慧  孟焕文  Julie D.Scholes  Stephen A.Rolfe 《园艺学报》2002,29(3):278-279

 以栽培番茄品种‘Ailsa Craig’的6 叶期幼苗为试材, 在水培条件下研究了5 %、7. 5 %和10 %聚乙二醇(PEG) 水分胁迫对叶片转化酶种类和活性表达及葡萄糖、果糖、蔗糖和淀粉代谢的影响。结果表明, 随着水分胁迫强度的加大, 可溶性酸性转化酶和胞壁转化酶活性增强, 己糖和蔗糖水平提高, 持续的强水分胁迫(10 % PEG) 使转化酶和可溶性糖水平显著增加, 而淀粉含量降低。  相似文献   

The comparative efficacy of abamectin, monepantel and an abamectin/derquantel combination against fourth-stage larvae of a macrocyclic lactone-resistant Teladorsagia spp. isolate infecting sheep     

George SD  George AJ  Stein PA  Rolfe PF  Hosking BC  Seewald W 《Veterinary parasitology》2012,188(1-2):190-193

Anthelmintic resistance by gastrointestinal nematodes of sheep continues to be an issue of global interest. While the recent introduction in some countries of one or two new anthelmintic classes (amino-acetonitrile derivatives [AAD] and spiroindoles [SI]) has been welcomed, it is important that there is no relaxation in parasite control and the management of drug resistance. Monepantel (an AAD) was the first new anthelmintic to be approved for use (New Zealand, 2009) and was followed a year later in the same country by a combination of derquantel (a SI) and abamectin. The present study determined the efficacy of the new anthelmintic products and abamectin against fourth-stage larvae of macrocyclic lactone-resistant Teladorsagia spp. in lambs. Efficacies were calculated by comparing post-mortem nematode burdens of treated animals with those of untreated control sheep, and were 98.5, 86.3 and 34.0% for monepantel, abamectin/derquantel and abamectin, respectively. The nematode burdens of monepantel- and abamectin/derquantel-treated sheep were significantly lower than those sheep treated with abamectin and the untreated controls. Similarly, the burden of the monepantel group was significantly lower than that of the abamectin/derquantel group. These findings provide an opportunity to reinforce the recommendation that farmers and animal health advisors need to know the resistance status of nematode populations on subject farms to ensure effective control programs are designed and implemented. Such control programs should include an appropriate choice of anthelmintic(s), monitoring parasite burdens for correct timing of treatments, and pasture management to reduce larval challenge balanced with the maintenance of drug-susceptible populations in refugia.  相似文献   

Efficacy of monepantel and anthelmintic combinations against multiple-resistant Haemonchus contortus in sheep, including characterisation of the nematode isolate     

Baker KE  George SD  Stein PA  Seewald W  Rolfe PF  Hosking BC 《Veterinary parasitology》2012,186(3-4):513-517

Three experiments defined the resistance profile of a population of Haemonchus contortus, which was shown to express multiple resistances to the benzimidazole, levamisole, macrocyclic lactone and salicylanilide anthelmintic classes when given as a registered combination. Study 1 was a faecal egg count reduction (FECR) test and the efficacies for the anthelmintics were monepantel, 100%; abamectin+levamisole+oxfendazole, 40.0%; and abamectin+levamisole+oxfendazole+naphthalophos, 100%. No larvae were recovered from the post-treatment cultures for monepantel or the 4-way treatment, and for the 3-way treatment the culture was 100% Haemonchus spp. Efficacies in Study 2 were calculated from mean post-mortem nematode burdens of H. contortus and were levamisole+oxfendazole, 3.1%; abamectin+levamisole+oxfendazole, 5.0%; ivermectin, 0.4%; moxidectin, 28.4% and closantel, 70.2%. Study 3 was also a FECR test that resulted in efficacies of 100% for monepantel and 83.0% for a formulated 4-way combination of abamectin+levamisole+albendazole+closantel. Larvae recovered from the post-treatment culture for the combination-treated sheep were all Haemonchus spp. Multi-resistant parasites such as examined in these studies are a continuing challenge to be managed by farmers and their advisors. Control programs must be planned and well-managed, and should include on-farm testing for anthelmintic resistance, monitoring of nematode burdens (by FEC and larval culture) to determine appropriate treatment times and the management of pastures to reduce the overall parasite challenge. This should be in balance with the generation, use and maintenance of drug-susceptible nematode populations in refugia.  相似文献