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191.
R. W. Gibson 《Potato Research》1974,17(2):152-154
Summary The foliage of hybrids ofS. tuberosum cv. Pentland Crown andS. berthaultii bore four-lobed, glandular hairs which, when ruptured by aphid movements, released a sticky substance which glued the aphids
to the plant. The transference of this property makes it more worthwhile testing as a means of decreasing the spread of aphid-borne
viruses. 相似文献
192.
Summary A clone ofSolanum berthaultii P.I. 265858 was not systemically infected when manually inoculated with isolates of PVX groups 1 to 3 but developed top-necrosis
when grafted-inoculated, demonstrating it is hypersensitive. Plants sap- or graft-inoculated with an isolated of PVX group
4 or with PVXHB (a recently-discovered strain overcoming all reported sources of resistance to PVX) were infected systematically. The plants
were extremely sensitive to these isolates, young leaves becoming necrotic and the plant dying within a few weeks and, whilst
still alive, plants contained little virus and were a poor source of infection. These characteristics suggest that this clone
could provide a means of breeding cultivars that would be protected against all known strains of PVX. 相似文献
193.
Summary Resistance to damage by the mitePolyphagotarsonemus latus (Banks) occurred inSolanum polyadenium Greenm. and in seedlines ofS. tarijense Hawkes andS. berthaultii Hawkes which had foliar hairs with a sticky tip.
On secondment from Rothamsted Experimental Station, Harpenden, Herts., England. 相似文献
194.
Krasnoff SB Lobkovsky EB Wach MJ Loria R Gibson DM 《Journal of agricultural and food chemistry》2005,53(24):9446-9451
The thaxtomin phytotoxins (1 and 2) from scab-producing Streptomyces pathogens of the potato are 2,5-dioxopiperazines consisting of modified l-tryptophanyl and l-phenylalanyl units. Thaxtomin A (1) is hydroxylated at C-14, the alpha carbon of the modified l-phenylalanyl moiety. Refluxing thaxtomin A in acidified MeOH, EtOH, and i-PrOH afforded C-14 thaxtomin A methyl- (3a and 3b), ethyl- (4a and 4b), and isopropyl- (5a and 5b) ethers, respectively, in both the 11S,14R (3a, 4a, and 5a) and 11S,14S (3b, 4b, and 5b) configurations. Crystal structures were determined for 3a and 4a. Extensive NMR as well as other spectroscopic data supported structural assignments for all of the derivatives. The 11S,14R-configured derivatives were slightly less potent than the natural products (1 and 2) as inhibitors of lettuce seedling root growth, whereas the activity of the 11S,14S epimers was much reduced, indicating that the configuration at C-14 found in the naturally occurring thaxtomins is essential for biological activity. Among the 11S,14R-configured compounds, potency decreased with an increasing size of the substituted alkoxy group. 相似文献
195.
Saman C Buddhadasa Sebastion Barone Elizabeth Gibson Stephen W. Bigger John D. Orbell 《Journal of Soils and Sediments》2002,2(3):137-142
Environmental consultants and analytical laboratories are increasingly realizing the importance of analytical method selection
and validation for the reliable measurement of soil contamination. Aromatic hydrocarbons (BTEX) is one class of environmentally
significant soil contamination for which testing is required by regulatory authorities in most industrialized countries. Unfortunately,
in most guidelines there is a lack of direction for the selection of a testing method for BTEX and, in practice, any one of
a variety of methods may be employed. The fact that these may not all yield comparable results is a source of much frustration
in the industry and there is a paucity of published research into this problem. In a number of carefully controlled experiments,
the method dependency of measured BTEX levels in contaminated soil samples has been investigated. Three commonly employed
methods, namely, (methanol extraction) purge-and-trap/gas chromatography with mass selective detection (P&T/GCMSD), headspace/GCMSD
and dichloromethane (DCM) extraction/gas chromatography with flame ionization detection (GCFID) have been compared in the
analysis of 109 gasoline-contaminated soil samples collected from station sites in Melbourne, Australia. Measurable BTEX concentrations
were recorded in 92% of the samples using P&T/GCMSD, 59% using DCM/GCFID, and 40% using headspace/GCMSD. Correspondingly,
the magnitudes of the recovered concentrations were significantly higher by P&T/GCMSD than by DCM/GCFID, which in turn were
significantly higher than the magnitudes determined by headspace/GCMSD. These trends are evident for both clay and sandy soils.
These studies clearly demonstrate that, for the three commonly employed methods described, measured BTEX levels are extraction
and analytical method dependent in at least two different soil types. 相似文献
196.
Gibson Michelle R. Runge Claire A. Stephens Philip A. Fuller Richard A. Willis Stephen G. 《Landscape Ecology》2022,37(1):191-208
Landscape Ecology - Nomadism is a movement strategy in response to non-seasonal environmental variability. Knowledge of nomadic species movements is poor but is necessary to understand life... 相似文献
197.
IR Gibson 《New Zealand veterinary journal》2013,61(1)
A 5-week-old crossbred pigdog pup was presented in respiratory distress. It appeared to dry retch, and then died suddenly before a clinical examination was performed; a littermate had died suddenly the week before. Histopathological examination revealed an ongoing lymphocytic myocarditis, characterised by myofibril degeneration and lymphocytic inflammatory infiltrates. In scattered degenerate myofibres, there were large amphophilic intranuclear inclusion bodies distending their nuclei. There was also marked pulmonary oedema. Canine parvoviral myocarditis, due to canine parvovirus type 2, was diagnosed. Further questioning regarding the history of this pup revealed that it had been born to an unvac-cinated dam that had been moved late in her pregnancy from an isolated farm on to another property. It seems likely that the dam was naïve and only became exposed to the virus immediately prior to whelping. The lack of wildlife vectors and a well-controlled population of dogs in rural New Zealand means that there may be isolated areas of the country where dogs can reach maturity without becoming exposed to parvovirus, creating the potential for development of this now uncommon syndrome. When parvovirus first arose in New Zealand, between 1979–;1981, parvoviral myocarditis was relatively common, occurring in neonates when the virus was introduced to breeding kennels that previously had been unexposed. 相似文献
198.
199.
Krasnoff SB Sommers CH Moon YS Donzelli BG Vandenberg JD Churchill AC Gibson DM 《Journal of agricultural and food chemistry》2006,54(19):7083-7088
NG-391 (1) and NG-393 (2), previously reported from undescribed Fusarium species as nerve-cell growth stimulants, were identified from fermentation extracts of the entomopathogenic fungus Metarhizium anisopliae. These compounds are 7-desmethyl analogues of fusarin C and (8Z)-fusarin C, mutagenic toxins from Fusarium species that contaminate corn. A mutant strain of M. anisopliae (KOB1-3) overproduces 1 and 2 by ca. 10-fold relative to the wild-type strain, ARSEF 2575, from which it was derived. Overproduction of these compounds in KOB1-3 imparts a yellow pigmentation to the culture medium of the fungus. These compounds were inactive at 100 mug/disk in antimicrobial disk diffusion assays. Compound 1 was inactive at 100 ppm in a mosquitocidal assay. However, like their fusarin analogues, 1 and 2 exhibited potent S9-dependent mutagenic activity in the Salmonella mutagenicity test. Discovery of these highly mutagenic mycotoxins in M. anisopliae suggests that screening for production of NG-391 and NG-393 in strains that are used as biocontrol agents would be a prudent course of action. The impact of these findings on the use of M. anisopliae as a biocontrol agent is currently unknown and requires further investigation. 相似文献
200.