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71.
Raphaëlle Mouttet Abraham Escobar‐Gutiérrez Magali Esquibet Laurent Gentzbittel Didier Mugniéry Philippe Reignault Corinne Sarniguet Philippe Castagnone‐Sereno 《Pest management science》2014,70(7):1017-1022
In Europe, the stem and bulb nematode Ditylenchus dipsaci has been listed as a quarantine pest by EPPO: without any control, it may cause complete failure of alfalfa crops. Movement of nematodes associated with seeds is considered to be the highest‐risk pathway for the spread of this pest. Since the 2010 official withdrawal of methyl bromide in Europe, and in the absence of any alternative chemical, fumigation of contaminated seed batches is no longer possible, which makes the production of nematode‐free alfalfa seeds difficult to achieve and leads to unmarketable seed batches. Thermotherapy is being considered as a realistic alternative strategy, but its efficiency still remains to be validated. The combination of the currently available methods (i.e. use of resistant cultivars, seed production according to a certification scheme, mechanical sieving, seed batch inspection) could significantly reduce the likelihood of seed contamination. However, it does not guarantee a total eradication of the nematode. Although it is already widely distributed all over Europe, reclassification of D. dipsaci as a regulated non‐quarantine pest to reduce the possibility of further introductions and the rate of spread of this pest appears to be a risky strategy because of the lack of up‐to‐date documented data to evaluate damage thresholds and determine acceptable tolerance levels. [[ArtCopyrightmsg]] 相似文献
72.
Background
The repeated weekly subculture of plant cell suspension is labour intensive and increases the risk of variation from parental cells lines. Most of the procedures to preserve cultures are based on controlled freezing/thawing and storage in liquid nitrogen. However, cells viability after unfreezing is uncertain. The long-term storage and regeneration of plant cell cultures remains a priority. 相似文献73.
Jason Holderieath Corinne Valdivia Larry Godsey Carla Barbieri 《Agroforestry Systems》2012,86(3):345-353
Global carbon trading may present a unique opportunity to change the rural landscape by allowing landowners to make an environmental impact with financial incentives. By enticing point source polluters to trade to an optimal level of pollution by offsetting their emissions with compatible carbon reduction projects, markets are able to facilitate a cleaner environment. Agroforestry provides a set of practices that can sequester carbon with managed tree and crop plantings. However, the initial lack of financial resources has been an obstacle to its adoption in the United States. This paper explores the potential for carbon offset trading to provide an added incentive to adopt agroforestry practices. Chicago Climate Exchange carbon sequestration projects are used as a baseline assessment, and the requirements that Missouri landowners would need to do in terms of contracting and ownership are identified. Data from landowners in central Missouri and the Ozarks (353 individuals) are used to determine characteristics of potentially interested landowners in agroforestry. A model to evaluate agroforestry profitability scenarios is used to compare the added carbon credit trading revenue to traditional alternate uses for the property. The findings from this analysis indicate that in the current context carbon trading does not provide an added incentive value for Missouri landowners to adopt either silvopasture or alley cropping practices because of the low magnitude of annual return. 相似文献
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Denoeud F Henriet S Mungpakdee S Aury JM Da Silva C Brinkmann H Mikhaleva J Olsen LC Jubin C Cañestro C Bouquet JM Danks G Poulain J Campsteijn C Adamski M Cross I Yadetie F Muffato M Louis A Butcher S Tsagkogeorga G Konrad A Singh S Jensen MF Cong EH Eikeseth-Otteraa H Noel B Anthouard V Porcel BM Kachouri-Lafond R Nishino A Ugolini M Chourrout P Nishida H Aasland R Huzurbazar S Westhof E Delsuc F Lehrach H Reinhardt R Weissenbach J Roy SW Artiguenave F Postlethwait JH Manak JR Thompson EM 《Science (New York, N.Y.)》2010,330(6009):1381-1385
Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain. 相似文献
76.
Alexis Peppuy Alain Robert Jean-Paul Delbecque Jean-Louis Leca Corinne Rouland Christian Bordereau 《Pest management science》1998,54(1):22-26
The efficacy of hexaflumuron, a benzophenylurea insecticide, has been studied for the first time on a fungus-growing termite (Pseudacanthotermes spiniger Sjöstedt, Macrotermitinae). Results show that hexaflumuron could be useful in treating infestations of such pest species, which are of great economic importance in many tropical and equatorial countries. Foraging workers harvested and introduced treated food into the nest and subsequently contaminated the brood by trophallaxis. Hexaflumuron showed potent larvicidal activity. The compound did not appear to be rapidly degraded by the digestive enzymes of termite workers, nor by the symbiotic fungus Termitomyces eurhizus Heim growing on fungus combs. This chitin synthesis inhibitor did not act as a fungicide, since growth of the mycelium of this fungus was not inhibited in vitro. © 1998 Society of Chemical Industry 相似文献
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78.
Robin A. Choudhury Hong Ling Er Marc A. Hughes Jason A. Smith Gretchen E. Pruett Joshua Konkol Randy C. Ploetz James J. Marois Karen A. Garrett Ariena H. C. van Bruggen 《Plant pathology》2021,70(3):676-688
Host size, density, and distribution, in addition to climate, can affect the likelihood a pathogen will invade and saturate landscapes. Laurel wilt, caused by the vector-borne pathogen Raffaelea lauricola, has devastated populations of native Lauraceae in the south-eastern USA, and continues to spread. We surveyed 87 plots in six coastal islands in South Carolina, Georgia, and north Florida, and one inland site (Archbold Biological Station) in south Florida for laurel wilt-affected and unaffected individual plants belonging to the genus Persea. The coastal island sites were surveyed once in 2008 or 2009, and the inland site was surveyed eight times from 2011 to 2013. Disease incidence per plot ranged from 0% to 96%, with mean disease incidence 42% across all sites. Disease incidence was positively correlated with trunk diameter and with density of hosts with trunk diameter >5 cm, but negatively correlated with the degree of clustering, which was highest for small trees. A recursive partitioning model indicated that higher disease incidence was associated with moderate temperatures, wider trunk diameter, lower relative humidity, and lower wind speeds. Disease progress over time at Archbold followed a Gompertz curve, plateauing at 3% in 2 years. The dispersal kernel for disease incidence from a focus followed a negative exponential distribution. The number of plots with diseased trees at Archbold was similar for redbay (P. borbonia) and swampbay (P. palustris) but was lower for silkbay (P. humilis). Understanding how host density, size, and diversity interact with environmental effects will help guide future risk prediction efforts. 相似文献
79.
This report describes a case of Mycobacterium tuberculosis infection in a green-winged macaw (Ara chloroptera), confirmed by microbiologic and pathologic diagnostics, and notes a possible human-avian transmission. Clinical signs included cutaneous swellings, profound leukocytosis, and signs of osteomyelitis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation with intralesional acid-fast rods. Mycobacterium tuberculosis was isolated from subcutaneous nodules and biochemically confirmed. The disease in avian species is of zoonotic importance. 相似文献
80.