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131.
A J INMAN B D L FITT S J WELHAM R L EVANS D A MURRAY 《The Annals of applied biology》1997,130(2):239-253
When leaves of oilseed rape (cv. Cobra) were inoculated with conidial suspensions of Mycosphaerella capsellae (white leaf spot) and incubated in controlled environments, the lag period from inoculation to the appearance of the first lesions decreased, and the total number of lesions produced increased, as temperature increased from 5oC to 20oC, although differences between 15oC and 20oC were small. With incubation period estimated as the time from inoculation until 5%, 50% or 95% of the lesions were produced, there was a linear relationship between l/(incubation period in days) and temperature over the range 5oC to 20oC, from which values at intermediate temperatures could be estimated. Summed mean daily temperatures from inoculation to the production of 5% of the lesions were estimated as 115–130 degree-days in the controlled environment experiments at 5oC to 20oC. When pods or leaves of plants in oilseed rape crops (cv. Cobra or cv. Libravo) were inoculated with conidial suspensions of M. capsellae on five occasions from January to October, with variable temperatures during the incubation period, degree-days until the first appearance of lesions were in the range 115–230. The numbers of white leaf spot lesions cm-2 which developed on inoculated leaves differed greatly between nine oilseed rape cultivars, with most on cv. Tapidor and fewest on cv. Libravo, but the incubation period differed little between cultivars. Similarly, the number of lesions which developed differed between four M. capsellae isolates from different regions but the incubation period did not. 相似文献
132.
GEORGE WILLIAM TUCKWELL KATHRYN ALLEN STEPHEN ROBERTS JOHN WILLIAM MURRAY 《The Journal of eukaryotic microbiology》1999,46(3):248-253
ABSTRACT. The characteristic grain size distributions observed in the test walls of agglutinated foraminifera can be replicated by numerical simulations. the logistics employed by the model parallel those seen in foraminifera during culturing experiments of test construction. Both fractal and log-normal grain distributions are generated by a simple space-filling algorithm. However, to generate the specific grain distributions observed in foramimferan tests a strong preference for selecting larger grains from the available sediment must be effected. the exclusion of smaller grains, during selection, produces log-normal grain distributions similar to those previously observed. These and similar modelling techniques may provide valuable insights into the mechanisms of shell construction employed by protists. 相似文献
133.
MURRAY H. BRILLIANT RICHARD KING UTA FRANCKE SIMONE SCHUFFENHAUER THOMAS MEITINGER JOHN M. GARDNER DONNA DURHAM-PIERRE YOSHIMICHI NAKATSU 《Pigment cell & melanoma research》1994,7(6):398-402
Mutations at the mouse pink-eyed dilution locus, p, cause hypopigmentation. We have cloned the mouse p gene cDNA and the cDNA of its human counterpart, P. The region of mouse chromosome 7 containing the p locus is syntenic with human chromosome 15q11-q13, a region associated with Prader-Willi syndrome (PWS) and Angelman syndrome (AS), both of which involve profound imprinting effects. PWS patients lack sequences of paternal origin from 15q, whereas AS patients lack a maternal copy of an essential region from 15q. However, the critical regions for these syndromes are much smaller than the chromosomal region commonly deleted that often includes the P gene. Hypopigmentation in PWS and AS patients is correlated with deletions of one copy of the human P gene that is highly homologous with its mouse counterpart. A subset of PWS and AS patients also have OCA2. These patients lack one copy of the P gene in the context of a PWS or AS deletion, with a mutation in the remaining chromosomal homologue of the P gene. Mutations in both homologues of the P gene of OCA2 patients who do not have PWS or AS have also been detected. 相似文献
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135.
MARK S. J. CRANE MARK J. GNOZZIO P. KEITH MURRAY 《The Journal of eukaryotic microbiology》1986,33(1):94-98
ABSTRACT. A quantitative technique for the assessment of sporozoite infectivity in vivo, using intra-cecal inoculation of Eimeria tenella sporozoites, has been developed. Evaluation of the infection using cecal lesion scores and oocyst counts showed that this technique should be useful for the quantitation of sporozoite viability and thus for the anti-sporozoite activity of different treatments prior to inoculation. Pre-treatment of sporozoites with heat-inactivated hyperimmune antisera neutralized sporozoite infectivity in vivo and indicated that antibodies in the absence of complement inhibited sporozoite infectivity in vivo. 相似文献
136.
137.
KEITH R. W. HAMMETT BRIAN G. MURRAY F.L.S. KENNETH R. MARKHAM IAN C. HALLETT IMKE OSTERLOH 《Botanical journal of the Linnean Society. Linnean Society of London》1996,122(2):89-101
Experimental hybridization, cytogenetic observations, flower pigment analyses and scanning electron microscope observations of seed coat features were used to investigate the relationship between L. annuus L. and L. hierosolymitanus Boiss. Pod width, seed size, shape and surface ornamentation proved to be good diagnostic criteria for distinguishing the two taxa. Hybridization between various accessions of the two species revealed variation both between and within accessions. Enhanced anthocyanin levels were detected in the standard petals of the reciprocal hybrids made between two specific accessions of L. annuus and L. hierosolymitanus. The results of the investigations support the retention of L. annuus and L. hierosolymitanus as separate species. 相似文献
138.
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140.
MURRAY ITZKOWITZ 《Zoological Journal of the Linnean Society》1974,55(2):87-118
Three major social systems were observed: territorial, isolate, and gregarious. Territorials defend a particular area against intruders. Isolates neither chase conspecifics nor join other individuals, while gregarious species are found in groups. Some species of territorial pomacentrids were found in uni-specific colonies. As gregarious groups neared these colonies, they were attacked by several territorials. The number of chases directed against the various species of intruders was in proportion to the intruder's abundance in the study areas. Predators were uncommon and generally ignored. Isolates were either predators, or slow moving species. Gregarious species could be found in uni-specific or mixed-species groups. In mixed-species groups, there were three subunits: core, associate, and opportunist. Core species were always in the majority and led the group. Associates followed the core species for long periods of time and the opportunists were brief visitors. Quantitative comparisons between uni-specific and mixed-species groups revealed that associates tend to select the larger of the available core groups. Juveniles were also considered and compared to their adults. Juveniles did exhibit the general types of social behaviour found in adults. However, within a species, the adult's behaviour may be very different from their own juveniles. The coral, and the chases by pomacentrids, were related to the formation and dispersion of gregarious groups. 相似文献