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81.
Huchzermeyer FW Wallace DB Putterill JF Gerdes GH 《The Onderstepoort journal of veterinary research》2009,76(3):311-316
When large numbers of crocodile skins were downgraded because of the presence of small pin prick-like holes, collapsed epidermal cysts were found deep in the dermis of juvenile crocodiles while forming cysts were observed in hatchlings. Histopathology of these forming cysts showed the presence of intracytoplasmic inclusions in proliferating and ballooning epidermal cells. Pox virions were seen in electron microscope preparations made from the scabs of such early lesions. The partial sequencing of virus material from scrapings of these lesions and comparison of it with the published sequence of crocodile poxvirus showed the virus associated with the deep lesions to be closely related, but different. To differentiate between the two forms of crocodile pox infection it is suggested that the previously known form should be called "classical crocodile pox" and the newly discovered form "atypical crocodile pox". The application of strict hygiene measures brought about a decline in the percentage of downgraded skins. 相似文献
82.
Aneeta Pradhan Julie A. Plummer Matthew N. Nelson Wallace A. Cowling Guijun Yan 《Euphytica》2010,176(1):87-98
A triploid hybrid with an ABC genome constitution, produced from an interspecific cross between Brassica napus (AACC genome) and B. nigra (BB genome), was used as source material for chromosome doubling. Two approaches were undertaken for the production of hexaploids:
firstly, by self-pollination and open-pollination of the triploid hybrid; and secondly, by application of colchicine to axillary
meristems of triploid plants. Sixteen seeds were harvested from triploid plants and two seedlings were confirmed to be hexaploids
with 54 chromosomes. Pollen viability increased from 13% in triploids to a maximum of 49% in hexaploids. Petal length increased
from 1.3 cm (triploid) to 1.9 cm and 1.8 cm in the two hexaploids and longest stamen length increased from 0.9 cm (triploid)
to 1.1 cm in the hexaploids. Pollen grains were longer in hexaploids (43.7 and 46.3 μm) compared to the triploid (25.4 μm).
A few aneuploid offsprings were also observed, with chromosome number ranging from 34 to 48. This study shows that trigenomic
hexaploids can be produced in Brassica through interspecific hybridisation of B. napus and B. nigra followed by colchicine treatment. 相似文献
83.
Wallace RJ Oleszek W Franz C Hahn I Baser KH Mathe A Teichmann K 《British poultry science》2010,51(4):461-487
1. Plants and their biologically active chemical constituents, sometimes called secondary metabolites or bioactives, present numerous opportunities for the improvement of livestock production by inclusion in the diet. 2. Many such plant derived materials have well established therapeutic values in man; however, their potential as feed additives in animal production, particularly of poultry, remains largely unexploited. 3. There is increasing evidence indicating that they can be efficient in controlling diseases, and plant bioactives may also influence production parameters such as feed efficiency and product quality. 4. It has been reported that they may even replicate some of the effects of antibiotic growth promoters, which were banned from use in Europe from 2006. 5. This review assesses the status of plant bioactives in poultry production and their mode of action on avian physiology, particularly in the digestive tract. 相似文献
84.
A sample of fourteen horse rugs and two saddle blankets stored in south western Sydney, Australia, an area of known high dust mite prevalence in the human environment, were analysed for the presence of house dust mites. Dust samples from the rugs, blankets and 16 control sites were collected using a vacuum cleaner with a modified attachment and filter. Dust mites were extracted using an adapted floatation technique. Eight rugs and all control samples were positive for mites, which were confirmed to be house dust mites of the genus Dermatophagoides. This study confirms that exposure to house dust mites from horse rugs can occur, indicating that house dust mite allergen reactivity on intradermal and serum allergy testing in atopic horses may represent true dust mite hypersensitivity. Nevertheless, quantification studies will be necessary to ensure that there is adequate mite exposure for development of hypersensitivity, and further evaluation of immunological responses, avoidance and provocation, and specific immunotherapy are required to confirm the clinical relevance. To the authors’ knowledge, this is the first study to document the presence of house dust mites in the equine environment. 相似文献
85.
T. Wallace 《The Journal of Horticultural Science and Biotechnology》2013,88(2):172-183
SummaryRadish (Raphanus sativus) is an important crucifer vegetative crop in Japan. We studied the morphological and anatomical characteristics of radish roots over a 6-week period using three radish cultivars with three different root shapes: long-type (Lt), round-type (Rt), and thin-type (Tt). We found that significant differences in the thickness of the roots first appeared 4 weeks after sowing. In Lt and Rt plants, the roots thickened rapidly, especially in the middle section that is composed of the lower part of the hypocotyl and the upper part of the taproot. The taproot increased in length in Lt plants, but failed to elongate in Rt plants. In Tt plants, the roots showed much smaller increases in mean diameter and length. Transverse sections through the taproots showed significant differences, both in cell number and in cell size 4 weeks after sowing. Lt and Rt plants contained more cells in the secondary xylem and phloem than Tt plants, and cell expansion was also greater in the storage roots of the Lt and Rt cultivars. These results will contribute to a better understanding of the development of radish roots of different shape. 相似文献
86.
José Wilacildo de Matos Oliveiro Guerreiro-Filho Wallace Gon?alves Daniel Alves Ramiro Bárbhara Joana dos Reis Fatobene 《Euphytica》2011,181(2):253-260
The coffee leaf miner, Leucoptera coffeella, is the most important pest of Coffea arabica plantations in Brazil, and all cultivars are susceptible to the insect. However, distinct reactions have been observed in
other species, such as C. congensis and C. canephora. In this work, the occurrence of antixenotic response was surveyed in individuals of Coffea species, selected for resistance to the leaf miner at both field and laboratory conditions. Tests performed on young plants
from C. arabica cultivars Icatu Precoce IAC 3282, Mundo Novo IAC 515-20, Tupi IAC 1669-33 and Catuaí Amarelo IAC 62 demonstrated that these
were preferred for oviposition when pooled with seedlings from C. canephora cv. Apoat? IAC 2258. Apoat? was also preferred over C. racemosa for oviposition. Similar results were observed in tests using detached leaves, and higher amount of eggs was counted in the
cv Obat? IAC 1669-20 and Catuaí Vermelho IAC 81, and lower oviposition frequency was observed in C. canephora cv. Guarini IAC 1598. C. congensis showed an oviposition frequency between C. arabica and C. canephora. Also, the results suggest that the frequency of oviposition is co-related with the plant resistance level, during larvae
infection. 相似文献
87.
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
88.
Summary Image analysis gave better precision than colorimetry in measuring the darkening caused by excess free sugar during crisping
of potatoes. The image analyser was used to measure individual crisp Average Optical Density (AOD) values in order to examine
the variability of AOD within and between tubers. It is unnecessary to measure more than one crisp per tuber when assessing
breeding lines, although two crisps per tuber are recommended for quality control. Crisps from at least ten tubers should
be measured.
A ‘Quick Crisp’ method, in which single crisps from each of four tubers are judged against standard samples, is reported.
Regression of results from this method on crisp reflectance percentage (Agtron score) gaveR
2 of 0.967. However, the observer tended to overestimate at low values and underestimate at high values. Over several trials,
the crossover point varied from 15 to 50 Agtron score units.
Measurement of crisp colour variability for improving selection, management and purchasing decisions is discussed. 相似文献
89.
90.