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1.
Cabrera A Cox L Velarde P Koskinen WC Cornejo J 《Journal of agricultural and food chemistry》2007,55(12):4828-4834
The addition of organic amendments to soil increases soil organic matter content and stimulates soil microbial activity. Thus, processes affecting herbicide fate in the soil should be affected. The objective of this work was to investigate the effect of olive oil production industry organic waste (alperujo) on soil sorption-desorption, degradation, and leaching of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and terbuthylazine [N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine], two herbicides widely used in olive crops. The soils used in this study were a sandy soil and a silty clay soil from two different olive groves. The sandy soil was amended in the laboratory with fresh (uncomposted) alperujo at the rate of 10% w/w, and the silty clay soil was amended in the field with fresh alperujo at the rate of 256 kg per tree during 4 years and in the laboratory with fresh or composted alperujo. Sorption of both herbicides increased in laboratory-amended soils as compared to unamended or field-amended soils, and this process was less reversible in laboratory-amended soils, except for diuron in amended sandy soil. Addition of alperujo to soils increased half-lives of the herbicides in most of the soils. Diuron and terbuthylazine leached through unamended sandy soil, but no herbicide was detected in laboratory-amended soil. Diuron did not leach through amended or unamended silty clay soil, whereas small amounts of terbuthylazine were detected in leachates from unamended soil. Despite their higher sorption capacity, greater amounts of terbuthylazine were found in the leachates from amended silty clay soils. The amounts of dissolved organic matter from alperujo and the degree of humification can affect sorption, degradation, and leaching of these two classes of herbicides in soils. It appears that adding alperujo to soil would not have adverse impacts on the behavior of herbicides in olive production. 相似文献
2.
Tatiana da Rosa Guimar?es Carlos Guillermo Quiroz Caroline Rigotto Simone Quintana de Oliveira Maria Tereza Rojo de Almeida éverson Miguel Bianco Maria Izabel Goulart Moritz Jo?o Luís Carraro Jorge Alejandro Palermo Gabriela Cabrera Eloir Paulo Schenkel Flávio Henrique Reginatto Cláudia Maria Oliveira Sim?es 《Marine drugs》2013,11(11):4176-4192
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2. 相似文献
3.
Cabrera Blatter MF Del Prado B Miceli DD Gomez N Ivanic J Di Tollo B Gallelli MF Castillo VA 《Research in veterinary science》2012,93(3):1195-1202
In this study, two populations of dogs with pituitary dependent hypercortisolism (PDH) were compared over a 2-year period. One group had normal vision (Group A, n=27) and one group was blind (Group B, n=20). Group B was characterised by the rapid appearance of the clinical signs of PDH that precede blindness. We found increases in pre-adrenocorticotropic hormone cortisol (P=0.002), IL-6 (P=0.0001), insulin, and insulin sensitivity (detected with the Homeostatic Model Assessment, P<0.0001) in Group B but not in Group A. The nitric oxide (NO) and the total adiponectin concentrations decreased (P=0.0001 and P=0.02, respectively) in Group B versus Group A. The IL-6 and insulin concentrations and the HOMA-A index were positively correlated with the cortisol concentration and were negatively correlated with the NO concentration. With the exception of adiponectin, the other variables were associated with blindness. We concluded that blindness in PDH is a haemodynamic event associated with metabolic changes, with the increase in the IL-6 concentration and the decrease in the NO concentration affecting the retinal vasculature and producing a high risk of vision loss. 相似文献
4.
5.
如果管理得当,给哺乳期的仔猪补充乳可获得多方面的好处。为获得高断奶窝重而对母猪进行高繁殖性能和高营养需求的选择已使饲喂现代的母猪品种成为商业化养猪场中技术最先进的工作。如果青年母猪要 相似文献
6.
Hordeum chilense Roem. et Schult. is a diploid wild South American barley that contains genes of interest for cereal breeding, many of them
located on chromosome 1Hch. In the current study, two H. chilense-wheat addition lines with deletions in the 1Hch chromosome were used for sub-arm localization of five prolamin (glutenin and gliadin) loci and 33 EST-SSR marker loci on
chromosome 1Hch. The two sets of markers were distributed across five sub-arm chromosome regions. Three glutenin loci (Glu-H
ch
2, Glu-H
ch
3, Glu-H
ch
4) together with the gliadin locus Gli-H
ch
1 were located on the distal 20% of the 1HchS arm, whereas the glutenin locus Glu-H
ch
1 was on the proximal 88% region of 1HchL. Among 33 EST-SSR marker loci, 7 (21.2%) were on the 1HchS arm and, of them, 3 (9.1%) were on the distal 20% end and 4 (12.1%) on the proximal 80% region. The 26 loci (78.8%) on 1HchL were distributed across three different regions: 18 (78.8%) in the proximal 88%, 3 (9.1%) in the distal 12% and 5 (15.2%)
in a region less than 12% from the distal end. The deletions in the 1Hch chromosome added to the common wheat background were thus shown to be useful for determining the sub-arm location of EST-SSR
and prolamin loci. This could facilitate the identification of molecular markers linked to genes of agronomic interest and
the isolation of such genes for use in common wheat improvement. 相似文献
7.
Guillermo Cabrera Walsh Anthony S. Dimeglio Ashot Khrimian Donald C. Weber 《Journal of pest science》2016,89(1):21-29
Harlequin bug (Murgantia histrionica) is an important pest of cole crops in the USA. The adults and nymphs feed on aboveground plant tissues by sucking cell contents and can seriously damage the host. Current insect control measures on cole crops target mainly lepidopteran pests, and the insecticides generally used do not control harlequin bug, so alternative management practices need to be explored. Previous research has established the existence of a male-produced pheromone attractive to both sexes and nymphs of M. histrionica. In this work, two systems of marking bugs were tested to verify if the mark affected fitness traits such as survival and host location. In a second phase, marked individuals were placed on trap host plants baited with synthetic pheromone lures to test whether migration rates were related to M. histrionica density on the trap plants and the presence of the attractants. Neither marking system affected the survival or orientation of the subjects compared to unmarked individuals. The pheromone lures significantly increased the attractiveness of the trap plants, but did not increase the retention time of the plants compared to unbaited plants. Emigration from the trap plants showed a constant rate and seemed unrelated to bug density on the plants. However, a mean peak density of ca. 36 bugs/plant was calculated. Beyond this number, density tended to decrease. These successful marking methods and retention time models support development of M. histrionica management with trap crops, by providing tentative control thresholds and decision rules. 相似文献
8.
Oswaldo A. Rubio-Covarrubias Patrick H. Brown Steven A. Weinbaum R. Scott Johnson Raul I. Cabrera 《Scientia Horticulturae》2009
Mobile nitrogen (N) forms may be better N indicators of the N status of trees than total nitrogen (TN) due to their higher sensitivity to increasing N supply. A field experiment was carried out over a 3-year period to compare foliar concentrations of total N (TN), soluble N (SN), chlorophyll (Minolta SPAD readings), NH4–N and NO3–N as indicators of soil N availability in nectarine, Prunus persica L. Batsch, cv. ‘Fantasia’ (grafted on ‘Nemaguard’ peach, P. persica × P. davidiana) trees. Young trees were exposed to a range of fertilizer-N application rates. Based on correlation analysis, the best association between leaf N compounds with soil N supply and trunk diameter and/or fruit yield was obtained with TN and chlorophyll SPAD readings. Leaf concentrations of mobile N compounds (NH4–N and NO3–N) increased more than any other N compound under high N supply; however, their inconsistency among years and low leaf concentration difficult their use as N indicators. The optimum foliar TN for growth decreased with tree age, 4.4%, 3.6% and 3.3% in non-bearing 1-year-old trees, non-bearing 2-year-old trees and 3.3 fruit-bearing 3-year-old trees. The optimum SPAD readings were 40 in 2-year-old trees and 42 in 3-year-old trees. Stable N compounds (TN and chlorophyll SPAD) could be used to N diagnosis in the zone of N deficiency, and soluble N compounds (NH4–N and NO3–N) to diagnoses N excess. 相似文献
9.
Influence of cover crops on potential nitrogen availability to succeeding crops in a Southern Piedmont soil 总被引:1,自引:0,他引:1
Harry H. Schomberg Dinku M. Endale Ademir Calegari Ricardo Peixoto Mário Miyazawa Miguel L. Cabrera 《Biology and Fertility of Soils》2006,42(4):299-307
Winter cover crops are essential in conservation tillage systems to protect soils from erosion and for improving soil productivity.
Black oat (Avena strigosa Schreb) and oilseed radish (Raphanus sativus L.) could be useful cover crops in the southeastern USA, but successful adoption requires understanding their influence on
N availability in conservation tillage systems. Black oat and oilseed radish were compared to crimson clover (Trifolium incarnatum L.) and rye (Secale cereale L.) for biomass production and effects on N mineralization during the summer crop growing season from fall 1998 through summer
2002 near Watkinsville, GA. Rye produced 40 to 60% more biomass, although N contents were less than the other cover crops.
Oilseed radish and black oat N contents were similar to crimson clover. Black oat, oilseed radish, and crimson clover C/N
ratios were less than 30, whereas rye averaged 39. Amount of N mineralized in 90 days (N
min90) measured with in situ soil cores was 1.3 to 2.2 times greater following black oat, crimson clover, and oilseed radish than
following rye. No differences in N
min90 were found between black oats, crimson clover, and oilseed radish in 1999 and 2000. The amount of potentially mineralizable
N (N
0) was not different due to cover crop, but was 1.5 times greater in 2000 and 2002 than in 1999. The rate of N mineralization
(k) was 20 to 50% slower following rye than the other three cover crops. Black oat and oilseed radish biomass production and
soil N mineralization dynamics were more similar to crimson clover than to rye, which indicates that they could be used as
cover crops in the southeast without significant changes in N recommendations for most crops.
相似文献
Harry H. SchombergEmail: |
10.