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61.
Sally A. Bound K. M. Jones T. B. Koen M. J. Oakford M. H. Barrett N. E. Stone 《The Journal of Horticultural Science and Biotechnology》2013,88(5):559-567
A trial, at Spreyton in north-western Tasmania, studied the effects of Cytolin and NAA sprays on the thinning and shape of ‘Delicious’ apples. Untreated control and hand thinned trees were compared with trees treated with Cytolin or NAA alone, or in combination. Cytolin was applied at 25 mg 1~‘ at the king petal (KP) stage. NAA was applied at 8 mg I“1 at full bloom (FB) and 7,10, or 15 days after full bloom (AFB). Cytolin alone had no effect on thinning, fruit weight or on pip numbers but it did improve fruit shape. The combination of cytolin and NAA at FB overthinned. Cytolin and NAA combinations applied at all times after FB significantly decreased both mean fruit weight and pip numbers and reduced the percentage of fruit > 70 mm. All Cytolin-NAA combinations and the NAA treatments applied at 10 and 15 days AFB resulted in unacceptably high percentages of apples < 45 mm in diameter (pygmy fruit). It is recommended that Cytolin and NAA should not be used in the same spray programme. NAA alone is a most effective thinner at FB or seven days AFB. 相似文献
62.
T. R. Marks Sally E. Simpson 《The Journal of Horticultural Science and Biotechnology》2013,88(5):815-824
Three physiologically distinct forms of the same genotype of Quercus robur ‘Fastigiata’, all derived from adult budwood, were identified following the growth of severely-pruned hedge plants grafted onto juvenile seedling rootstocks. Only explants from the form displaying the juvenile-like characteristic of over-winter leaf retention were capable of establishing sustainable cultures in vitro, although growth was not as rapid as those from a two year old seedling source. Pruning to release correlative inhibition of buds low on the scion framework produced vigorous shoot growth, but explants from these failed to show sustained growth in vitro. Withholding light from stockplants reduced excessive phenolic oxidation in explants taken from flushing unripe shoots, however, despite a beneficial effect on culture initiation, later growth was dependent upon the juvenile- or adult-like physiology of the original explant. A new medium was devised for this subject, which in addition to promoting growth generally, also stimulated the flushing of shoot apices. The relevance to in vitro culture of expression of juvenile habit in the stockplant is discussed. 相似文献
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Garmyn AJ Hilton GG Mateescu RG Morgan JB Reecy JM Tait RG Beitz DC Duan Q Schoonmaker JP Mayes MS Drewnoski ME Liu Q VanOverbeke DL 《Journal of animal science》2011,89(9):2849-2858
The objective of this study was to determine the influence of beef LM nutrient components on beef palatability traits and evaluate the impact of USDA quality grade on beef palatability. Longissimus muscle samples from related Angus cattle (n = 1,737) were obtained and fabricated into steaks for trained sensory panel, Warner-Bratzler shear force (WBSF), lipid oxidation measured by thiobarbituric acid reactive substances (TBARS), fatty acid, and mineral composition analysis. Pearson phenotypic correlations were obtained by the correlation procedure of SAS. Beef palatability data were analyzed by the GLM procedure of SAS with USDA quality grade as the main effect. Specific mineral concentrations did not demonstrate strong correlations with WBSF or sensory traits (r = -0.14 to 0.16). However, minerals appeared to have a stronger relationship with flavor; all minerals evaluated except Ca and Mn were positively correlated (P < 0.05) with beef flavor. Stearic acid (C18:0), C18:2, C20:4, and PUFA were negatively correlated (P < 0.05) with all 3 panelist tenderness traits (r = -0.09 to -0.22) and were positively correlated (P < 0.05) with WBSF (r = 0.09 to 0.15). The MUFA were positively correlated (P < 0.05) with panelist tenderness ratings (r = 0.07 to 0.10) and negatively associated (P < 0.05) with WBSF (r = -0.11). The strongest correlations with juiciness were negative relationships (P < 0.05) with C18:2, C18:3, C20:4, and PUFA (r = -0.08 to -0.20). Correlations with beef flavor were weak, but the strongest was a positive relationship with MUFA (r = 0.13). Quality grade affected (P < 0.05) WBSF, TBARS, and all trained sensory panel traits, except livery/metallic flavor. As quality grade increased, steaks were more tender (P < 0.05), as evidenced by both WBSF and sensory panel tenderness ratings. Prime steaks were rated juiciest (P < 0.05) by panelists, whereas Select and Low Choice were similarly rated below Top Choice for sustained juiciness. Quality grade influenced (P < 0.05) beef flavor, but not in a linear fashion. Although there were significant correlations, these results indicate tenderness, juiciness, and flavor are not strongly influenced by individual nutrient components in beef LM. Furthermore, the positive linear relationships between USDA quality grade and beef palatability traits suggest quality grade is still one of the most valuable tools available to predict beef tenderness. 相似文献
65.
Yuechun Zhao J. Nigel B. Bell Abdul Wahid Sally A. Power 《Water, air, and soil pollution》2011,216(1-4):451-462
The response to ozone (O3) of a range of Chinese leafy vegetables was investigated with respect to both inter- and intra-specific differences in sensitivity. In the interspecific experiment local Chinese cultivars of pak choi, rape, leaf mustard, leaf lettuce and coriander were fumigated with 90?ppb O3 for 9?h daily for 22?C30?days. A similar fumigation was carried out using four different cultivars of pak choi. Sequential measurements were made of leaf injury, photosynthetic rate, stomatal conductance and chlorophyll fluorescence, together with dry weights at a final harvest. O3 injury appeared as white or yellow blemishes on the leaf surface of all species. The first signs of injury were seen following only 3-days?? O3 exposure (pak choi); the extent of injured leaf area increased over time for all species and cultivars, with 44.6% of the leaf area visibly injured for leaf mustard, the species with the greatest extent of injury, following 30-days?? exposure. Significant reductions in photosynthetic rate (22.7?C40.7%) and stomatal conductance (19.1?C33.1%) were found for all species and cultivars following O3 exposure. Plant productivity was also reduced in O3 compared to filtered air, with significant yield reductions for all species (11.1?C50.8% above-ground dry weight) as well as for all cultivars of pak choi (15.8?C28.1% above-ground dry weight). The mechanisms for observed impacts are discussed, together with the implications for current and future production of vegetables in the southern China province of Guangdong. 相似文献
66.
Sally E. Henderson Sara C. Pfeiffer Joseph Novak Tracy A. Peace 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(3):382-388
A 5.25-year-old cynomolgus macaque (Macaca fascicularis) was found to have a marked leukocytosis due to a lymphocytosis on routine quarantine laboratory data prior to inclusion in a preclinical research study. The majority of lymphocytes were characterized as intermediate to large with round to convoluted nuclei, coarse to clumped chromatin, rare prominent nucleoli, and moderate amounts of lightly basophilic cytoplasm that frequently contained small magenta granules and/or clear vacuoles. The animal had tested negative for several viruses and other etiologic agents found in nonhuman primates 1 week prior to shipment to the research facility. However, further evaluation of the blood smear revealed rare hemoflagellates, and later testing using real-time PCR and ELISA was confirmatory for Trypanosoma cruzi (T cruzi). Trypanosoma cruzi is a zoonotic pathogen responsible for Chagas disease in people and can have negative consequences on study results when positive animals are inadvertently used for preclinical research. This case report describes a marked large granular lymphocytosis in an otherwise healthy macaque as the only indication of infection with T cruzi in an animal believed to be negative for the infection. Additionally, it highlights the diagnostic limitations of screening tests to rule out diseases in animals intended to be used in preclinical studies. 相似文献
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A. J. Hilton H. E. Stewart S. L. Linton M. J. Nicolson A. K. Lees 《Potato Research》2000,43(3):263-271
Summary Optimum storage conditions to identify resistance to silver scurf among commercially grown potato cultivars were determined
in a series of experiments. Inoculation of field-grown tubers with a conidial suspension ofH. solani (concentration 104 conidia per ml of water) and incubation at 15°C with 95% RH for 1 month followed by 2 months at 85% RH produced the greatest
differences in disease severity between potato cultivars. Results with glasshouse-grown tubers were comparable with those
from field-grown tubers, indicating that the test could be used to identify resistance in wild species of potato and to understand
the inheritance of this resistance. 相似文献
69.
Multicenter case-control study of risk factors associated with development of vaccine-associated sarcomas in cats 总被引:1,自引:0,他引:1
Kass PH Spangler WL Hendrick MJ McGill LD Esplin DG Lester S Slater M Meyer EK Boucher F Peters EM Gobar GG Htoo T Decile K 《Journal of the American Veterinary Medical Association》2003,223(9):1283-1292
OBJECTIVE: To determine whether particular vaccine brands, other injectable medications, customary vaccination practices, or various host factors were associated with the formation of vaccine-associated sarcomas in cats. DESIGN: Prospective multicenter case-control study. ANIMALS: Cats in the United States and Canada with soft tissue sarcomas or basal cell tumors. PROCEDURE: Veterinarians submitting biopsy specimens from cats with a confirmed diagnosis of soft tissue sarcoma or basal cell tumor were contacted for patient medical history. Time window statistical analyses were used in conjunction with various assumptions about case definitions. RESULTS: No single vaccine brand or manufacturer within antigen class was found to be associated with sarcoma formation. Factors related to vaccine administration were also not associated with sarcoma development, with the possible exception of vaccine temperature prior to injection. Two injectable medications (long-acting penicillin and methyl prednisolone acetate) were administered to case cats more frequently than to control cats. CONCLUSIONS AND CLINICAL RELEVANCE: Findings do not support the hypotheses that specific brands or types of vaccine within antigen class, vaccine practices such as reuse of syringes, concomitant viral infection, history of trauma, or residence either increase or decrease the risk of vaccine-associated sarcoma formation in cats. There was evidence to suggest that certain long-acting injectable medications may also be associated with sarcoma formation. 相似文献
70.