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131.
Fabio Rossi Cavalcanti Mario Lucio Vilela Resende Joo Paulo Matos Santos Lima Joaquim Albenisio Gomes Silveira Jos Tadeu Abreu Oliveira 《Physiological and Molecular Plant Pathology》2006,68(4-6):198-208
The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion® 50 WG (0.2 g l−1)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO2 assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions. 相似文献
132.
Jiahao Shao Jie Wang Yanhong Li Mauricio A. Elzo Tao Tang Tianfu Lai Yuan Ma Mingchuan Gan Li Wang Xianbo Jia Songjia Lai 《Journal of animal physiology and animal nutrition》2021,105(2):345-353
This study aimed to determine whether high-fat diet (HFD) could cause growth, behavioural, biochemical and morphological changes in young female rabbits. Thirty-six female rabbits were randomly divided into two groups fed with either a high-fat diet (HFD) or a standard normal diet (SND) for 5 weeks. Growth and behavioural changes were recorded during the 5-week feeding period. Tissue samples, including blood and adipose tissue, were obtained after slaughter. HFD rabbits weighed more by the end of the feeding period, had a higher percent body weight and adipose tissue weight change and had longer body and bust lengths than SND rabbits. HFD rabbits significantly reduced their feed intake and feeding frequency during the fourth and fifth weeks. HFD rabbits also showed lower frequency of drinking and resting and increased stereotypical behaviour. Besides, HFD rabbits showed significant physiological abnormalities. HFD rabbits had higher serum cholesterol (TC) and triglycerides (TG) levels than SND rabbits at the end of the feeding period, and higher free fatty acid (FFA) levels than rabbits in the SND group after the third week of feeding. Serum thyroxine (T4) increased significantly in week 2 and week 5 and triiodothyronine (T3) increased significantly in week four. However, there was no significant change in serum glucose (GLU) and insulin (INS) levels. Additionally, HFD reduced the area and diameter of perirenal and subcutaneous fat cells and increased their density. Our findings suggest that HFD rabbits had higher weight gains, accumulation of fat, and more behavioural changes than SND rabbits. Although high levels of fat in the diet had a low impact on hyperglycaemia, it could lead to hyperlipidemia and hyperthyroidism. Our results also suggest that sustained HFD may cause the proliferation of adipocytes in young female rabbits. 相似文献
133.
Palacios SM Maggi ME Bazán CM Carpinella MC Turco M Muñoz A Alonso RA Nuñez C Cantero JJ Defago MT Ferrayoli CG Valladares GR 《Fitoterapia》2007,78(7-8):580-584
Aerial parts of 27 plant species native to Argentina were tested in anti-insect, germination inhibition and bactericide bio-assays. In antifeedant assays on Epilachna paenulata larvae, 11 species showed strong feeding deterrent effects (higher than 90% at 200 microg/cm(2)). Twelve plants strongly inhibited the germination of Avena sativa seeds, but only six inhibited Raphanus sativum germination at 10 mg/ml. Four plants showed complete growth inhibition of Escherichia coli at a concentration of 2 mg/ml. 相似文献
134.
Bezerra IC de O Resende R Pozzer L Nagata T Kormelink R De Avila AC 《Phytopathology》1999,89(9):823-830
ABSTRACT During a survey conducted in several different regions of Brazil, two unique tospoviruses were isolated and characterized, one from chrysanthemum and the other from zucchini. The chrysanthemum virus displayed a broad host range, whereas the virus from zucchini was restricted mainly to the family Cucurbitaceae. Double-antibody sandwich-enzyme-linked immunosorbent assay and western immunoblot analyses demonstrated that both viruses were serologically distinct from all reported tospovirus species including the recently proposed peanut yellow spot virus and iris yellow spot virus (IYSV) species. The nucleotide sequences of the nucleocapsid (N) genes of both viruses contain 780 nucleotides encoding for deduced proteins of 260 amino acids. The N proteins of these two viruses displayed amino acid sequence similarities with the previously described tospovirus species ranging from 20 to 75%, but they were more closely related to each other (80%). Based on the biological and molecular features, these viruses are proposed as two new tospovirus species, designated chrysanthemum stem necrosis virus (CSNV) and zucchini lethal chlorosis virus (ZLCV). With the identification of CSNV and ZLCV, in addition to tomato spotted wilt virus, groundnut ring spot virus, tomato chlorotic spot virus, and IYSV, Brazil harbors the broadest spectrum of tospovirus species reported. 相似文献
135.
Milton Moreano Rosero Mauricio Aguirre Davinson Pezo Gonzalo Taborda Carmen Dussán Cristina Nerin 《Water, air, and soil pollution》2012,223(2):667-678
Three different solventless sample preparation techniques based on microextraction, membrane extraction, and headspace extraction
have been developed and optimized for determination of trihalomethanes in drinking water by gas chromatography electron capture
detector and mass spectrometry detection. The techniques employed were headspace (HS) solid-phase microextraction, hollow
fiber liquid-phase microextraction (HFLPME) and HS extraction. All techniques used were optimized with different experimental
designs in order to select the most relevant variables which significantly affect the different processes. The different analytical
figures of merit such as limit of detection (LOD), limit of quantification, reproducibility, accuracy, and linear dynamic
range were obtained. The new HFLPME method applied used a hollow fiber membrane of polypropylene and the optimized variables
were extraction time, extraction temperature, and salting-out effect. The software MODDE 6.0 was used and its design was one
central composite on face with a total of 17 runs. The best conditions for the HFLPME were 20 min, 40°C, and 10% NaCl, respectively.
The LODs ranged from 0.018 μg·L−1 (for CHClBr2) to 0.049 μg·L−1 (for CHBr3), being this technique the most sensitive one among those studied. Finally, after having optimized the sample preparation
techniques and chromatographic conditions, several water samples were taken in two different water treatment plants in Spain
(Zaragoza) and Colombia (Viterbo, Caldas). The results obtained are shown and discussed. 相似文献
136.
Mauricio Parra-Quijano José M. Iriondo Elena Torres 《Genetic Resources and Crop Evolution》2012,59(2):205-217
Information on plant adaptation can be very useful in agrobiodiversity studies. Ecogeographical land characterization (ELC)
maps constitute a new tool in this direction with great potential. To assess the usefulness of this approach, an ELC map of
Spain was created through multivariate methods. Its performance to characterize plant habitat preferences was compared with
existing ecological regions and land cover maps. Collecting sites and seed weight from eight plant species were used to test
the ELC map. Categories from each map were assigned to accessions using collecting sites. Chi-square tests were applied to
test if category frequency distributions for each species followed a distribution proportional to the relative frequency of
categories in each map. The tests found significant differences in the eight species studied. Thus, Bonferroni confidence
intervals (BCI) classified categories from maps in preferred, neutral or avoided habitats. Seed weight was used as a proxy
for plant adaptation. Comparison between observed and expected ranking of BCI and quartile classes in terms of seed weight
means, and GLM and post-hoc tests carried out to test the effect of these classes upon seed weight showed consistently better
results for the ELC map. Species results and applications of ecogeographic maps in plant genetic resources conservation are
discussed. 相似文献
137.
Peñuela Mauricio Viáfara-Vega Ronald Arias Leidy Laura Cifuentes-Silva Héctor López José Cárdenas Heiber 《Journal of Crop Science and Biotechnology》2022,25(2):161-172
Journal of Crop Science and Biotechnology - Usually is common to see great differences among plants in our crops, this can allow us to think about selection of some plants with the best traits in... 相似文献
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