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Ryckaert B Spanoghe P Heremans B Haesaert G Steurbaut W 《Journal of agricultural and food chemistry》2008,56(17):8041-8044
Tank-mix adjuvants can increase the overall performance of plant protection products. Their most important ways of action are the improved retention, spreading, wetting, and penetration of the pesticide on the target and the reduction of fine droplets. In this paper, deposition and spreading of the systemic fungicide propiconazole on triticale ears were quantified. A better deposition and spreading of fungicide on the ear may be a possible help for the Fusarium problem in triticale, wheat, and other cereals. Triticale ears were applied with propiconazole in combination with 11 different tank-mix adjuvants. Vegetable oil, alcohol ethoxylates, lactate ester, trisiloxanes, and an amphoteric molecule were included in this experiment. When no tank-mix adjuvant was used, the lower part of the ear was reached five times less by the propiconazole spray than the upper part of the ear. When the tank-mix adjuvant was combined with the propiconazole formulation, an increase in residue on both the upper and the lower part of the ear was observed. A higher residue on the upper half of the ear means a better deposition, while a higher residue on the lower part of the ear is related to a better downward spreading over the grains and the needles of the ear. The combination of those two observations makes it interesting to use tank-mix adjuvants for the prevention of mycotoxin-producing Fusarium species. The advantages are emphasized even more when cost effectiveness was calculated. The use of a proper tank-mix adjuvant can result in 40% lower cost per application per hectare. 相似文献
54.
Effect of cytokinins and lines on plant regeneration from long-term callus and suspension cultures of Allium cepa L. 总被引:1,自引:0,他引:1
Sijun Zheng Betty Henken Eri Sofiari Paul Keizer Evert Jacobsen Chris Kik Frans Krens 《Euphytica》1999,108(2):83-90
Research was conducted to study interrelationships between agronomic and seed characters and their direct and indirect effects on seed yield per plant under normal and limited irrigation regimes. Two field experiments were conducted in 1996 at the Experimental Station of College of Agriculture, Shiraz University at Badjgah. Fourteen sunflower (Helianthus annuus L.) cultivars consisting of eight hybrids and six open pollinated varieties were grown in two randomized complete block designs with four replications. Two experiments differed in respect to irrigation regime. The cause and effect relationships of 12 different characters were assessed. Most of the characters including seed yield and oil content showed considerable genotypic and phenotypic variations. Water stress significantly decreased yield and its components, however, oil content did not differ significantly. Genotypic and phenotypic correlations revealed that seed yield had significant positive correlations with days to flowering, days to physiological maturity, head diameter, plant height, 1000-seed weight and oil yield under normal and limited irrigation. Seed yield had significant correlations with oil content and kernel percentage under normal irrigation regime, while these correlations were largely reduced under stress conditions and were not significant. The highest direct effect, was exhibited by 1000-seed weight and number of filled seeds per head in normal and limited irrigation environments. However, cause and effect relations of other traits with seed yield changed due to irrigation conditions. Direct effect of oil content was quite lower than its correlation with seed yield. The lowest direct effect was found for plant height and oil content under normal and stress environments, respectively. 相似文献
55.
Betty CR Zhu Gregg Henderson Anne M Sauer William Crowe Roger A Laine 《Pest management science》2010,66(8):875-878
BACKGROUND: Research has shown that the family of grapefruit flavors called nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). RESULTS: Nineteen synthetic nootkatone derivatives, along with three commercially available nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two‐step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. CONCLUSION: Four derivatives of nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound nootkatone. Four other compounds have between 2 and 3 times the repellency of nootkatones, and three compounds are equal in their repellency to nootkatone. Copyright © 2010 Society of Chemical Industry 相似文献
56.
Identification of volatile compounds in soybean at various developmental stages using solid phase microextraction 总被引:1,自引:0,他引:1
Boué SM Shih BY Carter-Wientjes CH Cleveland TE 《Journal of agricultural and food chemistry》2003,51(17):4873-4876
Soybean (Glycine max) seed volatiles were analyzed using a solid phase microextraction (SPME) method combined with gas chromatography-mass spectrometry (GC-MS). Thirty volatile compounds already reported for soybean were recovered, and an additional 19 compounds not previously reported were identified or tentatively identified. The SPME method was utilized to compare the volatile profile of soybean seed at three distinct stages of development. Most of the newly reported compounds in soybean seed were aldehydes and ketones. During early periods of development at maturity stage R6, several volatiles were present at relatively high concentrations, including 3-hexanone, (E)-2-hexenal, 1-hexanol, and 3-octanone. At maturity stage R7 and R8, decreased amounts of 3-hexanone, (E)-2-hexenal, 1-hexanol, and 3-octanone were observed. At maturity stage R8 hexanal, (E)-2-heptenal, (E)-2-octenal, ethanol, 1-hexanol, and 1-octen-3-ol were detected at relatively high concentrations. SPME offers the ability to differentiate between the three soybean developmental stages that yield both fundamental and practical information. 相似文献
57.
Farm to school programs are at the vanguard of efforts to create an alternative agrifood system in the United States. Regionally-based,
mid-tier food distributors may play an important role in harnessing the potential of farm to school programs to create viable
market opportunities for small- and mid-size family farmers, while bringing more locally grown fresh food to school cafeterias.
This paper focuses on the perspectives of food distributors. Our findings suggest that the food distributors profiled have
the potential to help institutionalize farm to school programs. Notably, their relationships with farmers may be a critical
element in expanding the scale and scope of local school food procurement. Their ability to catalyze local school food procurement
however, is limited by the structural context in which farm to school programs operate. Specifically, the oppositional school
year and agriculture production cycle, and tight food service budget constraints disembed and limit the potential of farm
to school programs to decrease the “marketness” of school food procurement and to shift it from a process based largely on
price to one that is more territorially embedded. As farm to school programs continue to gain support, regionally-based food
distributors that have the meaningful relationships necessary to re-embed the school food service market back into the larger
society may be critical to enabling advocates to achieve their goals. 相似文献
58.
Samples of catsup from 13 commercial sources, representing at least 10 U.S. manufacturers, were analyzed for carotenoid content, antioxidant activity, and percentage solids. The solids content of these catsup brand samples varied from 26.31 to 38.06% solids. The lycopene content ranged from 59.42 to 183.36 microg, and total carotenoids were as high as 216.6 microg/g fresh weight, respectively. In addition, both hydrophilic and lipophilic antioxidant activities were measured using the Trolox equivalent antioxidant capacity (TEAC) assay. These measurements of samples of the various catsup brands ranged from 176.5 to 356.8 total TEAC units. 相似文献
59.
60.
Berzina I Sharkey LC Matise I Kramek B 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(3):332-338
Background: The diagnostic value of cytology compared with histopathology varies by tissue, but there is little information regarding this comparison involving canine bone. Objectives: The objective of this retrospective study was to compare primary pathologic processes for cytology and histopathology of canine bone lesions. We adopted a proposed standardized format for reporting studies of diagnostic accuracy. Methods: A computer search of canine medical records at the University of Minnesota Veterinary Medical Center from September 2002 through October 2006 identified 52 bone cytology samples that had incisional (IncB) and/or excisional (ExcB) biopsy performed. The primary pathologic process was determined by evaluation of original reports. Cytologic vs IncB and cytologic vs ExcB were compared pairwise for agreement. Agreement was compared for neoplastic and non-neoplastic processes using the combined IncB/ExcB data, which included all ExcB (n=21) and IncB when that was the only biopsy available (n=31). Combined data were used to determine the effect of cytology cellularity on the diagnostic correlation. Results: The correlation in primary process between cytology and IncB was 71%, and for ExcB was 71%. For lesions with a cytologic diagnosis of neoplasia compared with the combined IncB/ExcB data set, cytology and histopathology agreed in 92% of cases, which was significantly greater (P<.0001, chi(2)) than the 27% for non-neoplastic processes. Cytology cellularity significantly affected rates of correlation (P=.026), with high, moderate, and poor cellularity samples having concordant primary processes in 88%, 77%, and 47% of cases, respectively. Conclusions: Cytologic diagnosis of neoplasia for samples collected from canine bone correlates better with histopathology than cytologic diagnosis of non-neoplastic proliferative processes or inflammation. Cytologic diagnoses from highly cellular samples are more likely to correlate with histopathology than those from less cellular samples. 相似文献