Lettuce response to organic and phosphate fertilizers and root mycorrhization     

Luis Miguel Brito  Áurea Sampaio  Rui Pinto  Isabel Mourão  João Coutinho 《Journal of plant nutrition》2016,39(6):842-849

The response of lettuce to production system, organic and phosphate fertilizers and root mycorrhization, was evaluated in two pot trials with factorial treatment combination of: (i) soil type (from organic and from conventional production systems) and organic fertilizer (0, 2 and 4 t ha^?1) in the first trial; and (ii) mycorrhizal inoculation (mycorrhized and non-mycorrhized plants) and Gafsa phosphate (0, 100 and 200 kg P₂O₅ ha^?1) in the second. Lettuce growth decreased with increasing rates of the organic fertilizer because of its very high electrical conductivity (50.1 dS m^?1) and lack of maturation. However, the fertilizer harmful effects were minimized in the soil from organic production. The application of Gafsa phosphate significantly increased lettuce yield and nutrient uptake. However, for the highest rate of phosphate, mycorrhized lettuce yield decreased compared to non-mycorrhized lettuce, suggesting that high soil available P may have harmful effects on the activity of mycorrhizal fungi.  相似文献   

Modulations of the Bcl-2/Bax family were involved in the chemopreventive effects of licorice root (Glycyrrhiza uralensis Fisch) in MCF-7 human breast cancer cell   总被引：10，自引：0，他引：10  

Jo EH  Hong HD  Ahn NC  Jung JW  Yang SR  Park JS  Kim SH  Lee YS  Kang KS 《Journal of agricultural and food chemistry》2004,52(6):1715-1719

Recently, cancer chemoprevention with strategies using foods and medicinal herbs has been regarded as one of the most visible fields for cancer control. Genistein in soy, American ginseng, and resveratrol are well-known to have antiproliferative properties in human breast cancer. Licorice root is a botanical, a shrub native to southern Europe and Asia, which primarily has desirable qualities in sweetening and herbal medicine. In this study, licorice (Glycyrrhiza uralensis Fisch) root also inhibits cell proliferation in human breast cancer cell. The cell proliferation study demonstrated that licorice root reduced the proliferation of MCF-7 cells in a dose- and time-dependent manner. The extracts were fractionated in CHCl(3), EtOAc, C(6)H(14), and CH(3)OH-H(2)O (70:30), and these extracts of licorice root (50 microg/mL) induced DNA fragmentation demonstrated by Hoechst 33258 staining. Apoptosis also determined the sub-G1 accumulation by flow cytometry analysis. These results were consistent with specific cleavage of PARP and antiapoptotic protein Bcl-2 and up-regulation of proapoptotic protein Bax demonstrated by Western blotting. Our findings suggest that licorice root may have chemopreventive effects against human breast cancer through the modulation of the expression of the Bcl-2/Bax family of apoptotic regulatory factors.  相似文献   

Genetic relationships of Portuguese coles and other close relatedBrassica genotypes using nuclear RFLPs     

João S. Dias 《Genetic Resources and Crop Evolution》1995,42(4):363-369

Nuclear RFLPs were used to study the genetic relationships of 2 Portuguese coles, tronchuda cabbage and Galega kale, and 13 otherBrassica oleracea cultivars and 4 nine-chromosome wild brassicas. Cluster and principal coordinates analysis were conducted using RFLP data from 60 probe-enzyme combinations, detecting 277 polymorphic restriction fragments. The results showed that the accessions clustered in five groups: one with all theB. oleracea cultivars except kailan, and the four others isolated with kailan, wildB. oleracea, B. insularis andB. cretica, andB. montana, respectively. Kailan was separated from the other accessions ofB. oleracea cultivars and genetically close to the wildB. oleracea, that was clearly separated from the other nine-chromosome wild brassicas. In theB. oleracea cultivars 3 groupings were clearly individualized: i) including broccolis and cauliflower; ii) with a misture of kales and cabbages originally from Central-North Europe; iii) formed by Portuguese coles. These preliminary results suggest the existence of three major regions of domestication of B. oleracea in Europe: Italy, Central-North Europe and Portugal. Kailan or chinese kale seems to have evolved separately from the otherB. oleracea cultivars in Eastern Asia.  相似文献   

Analysis of methoxyfenozide residues in fruits, vegetables, and mint by liquid chromatography-tandem mass spectrometry (LC-MS/MS)   总被引：3，自引：0，他引：3  

Hall GL  Engebretson J  Hengel MJ  Shibamoto T 《Journal of agricultural and food chemistry》2004,52(4):672-676

Methoxyfenozide [3-methoxy-2-methylbenzoic acid 2-(3,5-dimethylbenzoyl)-2-(1,1-dimethylethyl) hydrazide; RH-2485], in the formulation of INTREPID, was applied to various crops. Analysis of methoxyfenozide was accomplished by utilizing liquid-liquid extraction and partitioning, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Method validations for fruits, vegetables, and mint are reported. Methoxyfenozide mean recoveries ranged from 72 to 129% over three levels of fortification. The overall average of mean recoveries is 97 +/- 10%. The limit of quantitation for fruits, artichoke, cucumber, squash, and refined sugar was 0.010 ppm, with a detection limit of 0.005 ppm. For all other crops, the limit of quantitation was 0.050 ppm, with a detection limit of 0.025 ppm. No residues were found greater than the limit of quantitation in control samples. Residues above the limit of quantitation were found in all matrices except refined sugar. Foliage (bean, beet, pea, and radish) had greater residue levels of methoxyfenozide residue than their corresponding roots or pods. Other crop matrices contained <1.0 ppm of methoxyfenozide except artichoke, which had a mean of 1.10 ppm.  相似文献   

Antioxidant properties of trans-epsilon-viniferin as compared to stilbene derivatives in aqueous and nonaqueous media   总被引：3，自引：0，他引：3  

Privat C  Telo JP  Bernardes-Genisson V  Vieira A  Souchard JP  Nepveu F 《Journal of agricultural and food chemistry》2002,50(5):1213-1217

trans-Epsilon-viniferin, the dimer of resveratrol, extracted from Vitis vinifera, has been evaluated for its antioxidant capacity. Its properties have been compared to those of resveratrol and synthetic stilbenic derivatives (4-hydroxystilbene, 4,4'-dihydroxystilbene, 3,5-dihydroxystilbene, and trimethylresveratrol), in regard to their liposolubility using two media with different polarity. The bleaching of beta-carotene by lipoperoxyl (LOO.) radicals in an oil/water (O/W) emulsion and the scavenging of superoxide anions (O(-)(2) in dimethyl sulfoxide (DMSO) using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap were followed using UV-visible and electron paramagnetic resonance, respectively. Epsilon-viniferin exhibits the best antioxidant capacity in the DMSO/O(-)(2) polar system (IC(50) = 0.14 mM) while 4,4'-dihydroxystilbene presents the highest antioxidant capacity in the O/W/LOO. system (inhibition of beta-carotene bleaching, 82%). Partition coefficients and kinetics of partition between 1-octanol and water were measured to discuss the antioxidant efficiency of the compounds in relation with their chemical structure.  相似文献   

Hydrolytic activation and detoxication of 2,4-dichlorophenoxyacetic acid esters in mosquito fish     

Howard Chambers  L.J. Dziuk  Jo Watkins 《Pesticide biochemistry and physiology》1977,7(3):297-300

Insecticide-resistant mosquito fish (Gambusia affinis) were found to be slightly more tolerant to two thiol esters of 2,4-dichlorophenoxyacetic acid (2,4-D) than were fish of a susceptible population. DEF (S,S,S,-tributyl phosphorotrithioate), at 0.1 ppm for 24 hr, slightly decreased the toxicity of both esters to both populations. Comparison of esterase activities in gill and liver preparations showed that the resistant fish had lower levels of liver esterases than the susceptible fish, but results with gill preparation were not consistent. With the ethyl thiol ester, susceptible fish had the higher activity, but with butyl thiol ester, resistant fish had the higher activity. DEF inhibited activities in both tissues of both populations, but inhibition was appreciably greater in the liver. Results suggest that (i) hydrolysis in the liver activaties 2,4-D esters, (ii) hydrolysis in the gill is a detoxication reaction, (iii) the slight increase in tolerance in the insecticide-resistant fish is primarily the result of decreased activation, and (iv) antagonism by DEF is the result of a greater inhibition of activation than of detoxication.  相似文献   

Modelling the interactions between phenology and insecticide resistance genes in the codling moth Cydia pomonella     

Boivin T  Chadoeuf J  Bouvier JC  Beslay D  Sauphanor B 《Pest management science》2005,61(1):53-67

In the codling moth Cydia pomonella (L), insecticide resistance genes have been associated with pleiotropic effects affecting phenology. In this paper, we investigated whether an increase in the frequency of insecticide resistance in field populations of C pomonella was likely to entail significant divergences in the temporal occurrence of both susceptible and insecticide-resistant individuals. For this purpose, we built a phenological model that provided suitable predictions of the distinct and diverging seasonal evolutions of populations of a susceptible and two insecticide-resistant (at two and three loci) homozygous genotypes of C pomonella. Model simulations for each genotype were further compared with pheromone trap catches recorded in a field insecticide-treated population over an 8-year period (from 1992 to 2000), which reflected the progressive annual increase in the frequency of resistance in southeastern France. We found a significant delay in field adult emergence relative to those predicted by the homozygous susceptible model, and the magnitude of such a delay was positively correlated with increasing frequencies of insecticide resistance in the sampled field population of C pomonella. Adult emergence predicted in the theoretical population that was homozygous for resistance at two loci converged with those recorded in the field during the investigated 8-year period. This suggested that the pleiotropic effects of resistance were likely to result in a significant phenological segregation of insecticide-resistant alleles in the field. The results of this study emphasized the potential for pest populations exposed to chemical selection to evolve qualitatively with respect to phenology. This may raise critical questions regarding the use of phenological modelling as a forecasting tool for appropriate resistance management strategies that would take into account the diverging seasonal evolutions of both insecticide resistance and susceptibility.  相似文献   

Risk assessment of dietary exposure to pesticides using a Bayesian method   总被引：2，自引：0，他引：2  

Paulo MJ  van der Voet H  Jansen MJ  ter Braak CJ  van Klaveren JD 《Pest management science》2005,61(8):759-766

Risk assessment of pesticides can be a statistically difficult problem because pesticides occur only occasionally, but they may occur on multiple components in the diet. A Bayesian statistical model is presented which incorporates multivariate modelling of food consumption and modelling of pesticide measurements which are for a large part below a measurement threshold. It is shown that Bayesian modelling is feasible for a limited number of food components, and that in a data-rich situation the model compares well with an empirical Monte Carlo modelling.  相似文献   

Estimated BVDV-prevalence, -contact and -vaccine use in dairy herds in Northern Portugal     

Niza-Ribeiro J  Pereira A  Souza J  Madeira H  Barbosa A  Afonso C 《Preventive veterinary medicine》2005,72(1-2):81-5; discussion 215-9

A study to evaluate BVDV-prevalence, recent -contact and -vaccine use in dairy herds in the "Entre Douro e Minho" (EDM) region in North Portugal was carried out in 124 dairy herds in 2003. Herds were visited to ascertain BVDV-vaccine use and to collect a bulk tank milk (BTM) sample and serum from 1268 cattle to analyse BVDV-antibodies using an NS2-3 ELISA. Fifty-three percent of farmers used inactivated BVDV-vaccines whilst the remaining farmers were not presently using BVDV-vaccines. BMT-antibody results included 35% positives, 25% negative and 39% inconclusive, and were similar in vaccinated and non-vaccinated herds (p>0.05) and allowed estimating a 10% BVDV herd-prevalence from prior knowledge of the relationship between BMT-antibody results and probability of PI cattle in the herd. Overall individual seroprevalence was 27% and was 23% in non-vaccinated and 36% in vaccinated cattle (p<0.05). Contact of the herd with BVDV was assessed according to seroprevalence in young and adult cattle in the herd and it was estimated that 35% of herds were infected or had recent contact with BVDV, 40% were not infected and did not have recent contact with BVDV and the BVDV-infection and -contact status of remaining herds was undetermined. The results from this study indicate BVDV is endemic and BVDV-vaccines are widespread in the dairy-cattle population in EDM region in Portugal.  相似文献   

Evaluation of tulathromycin for the treatment of pneumonia following experimental infection of swine with Mycoplasma hyopneumoniae   总被引：3，自引：0，他引：3  

McKelvie J  Morgan JH  Nanjiani IA  Sherington J  Rowan TG  Sunderland SJ 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):197-202

Tulathromycin was evaluated in the treatment of pneumonia in weaned pigs inoculated intranasally with Mycoplasma hyopneumoniae. Five days postchallenge, the pigs were randomized to treatment with a single IM administration of saline, a single IM administration of tulathromycin (2.5 mg/kg; day 0), or three IM administrations of enrofloxacin (5.0 mg/kg; days 0, 1, 2). Pigs were necropsied on day 12 or 13. Unchallenged controls remained healthy with no lung pathology. Compared with saline, coughing, mean lung lesion score, and proportional lung weight were significantly reduced and weight gain was significantly greater for tulathromycin-treated pigs (P < .05). Compared with enrofloxacin, there were no significant differences in proportional lung weight or weight gains, but coughing and lung lesion scores were greater for tulathromycin-treated pigs (P < .05). Tulathromycin was effective in the treatment of pneumonia following experimental infection with M. hyopneumoniae.  相似文献