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91.
In 2002 and 2003, six field experiments were conducted at three olive groves of southern Spain in order to compare the effects
of two types of ethylene treatments (sprayed and diffusers) on the olive losses caused by the olive moth (Prays oleae Bern.) as well as on the activity and effectiveness of oofagous predators. Both treatments showed to be effective to control
the pest; in the two years studied the mean reduction in final infestation due to ethylene was of 35% with respect to the
controls trees, and none affected negatively the action of natural predators of P. oleae. In addition, the use of diffusers set on the trees at the end of flowering period will help the farmers to overcome the
problems of determination of optimum time for sprayed treatments of ethylene. 相似文献
92.
93.
94.
Kawasaki PM Kano FS Tamekuni K Garcia JL Marana ER Vidotto O Vidotto MC 《Research in veterinary science》2007,83(3):347-354
Anaplasmosis, caused by Anaplasma marginale, results in significant economic losses of cattle in tropical and subtropical regions worldwide. Six major surface proteins (MSPs) were well characterized and designated as MSP1, MSP2, MSP3, MSP4, and MSP5. The objective of this study was to evaluate the humoral immune response of BALB/c mice against the recombinant MSPs, incorporated into immunostimulating complex (ISCOM). The recombinant proteins purified by Ni-NTA columns were incorporated into ISCOM and ISCOMATRIX by the lipid film hydration method. BALB/c mice immunized with ISCOM/rMSPs and ISCOMATRIX/rMSPs vaccines produced whole IgG, IgG1, and IgG2a, in contrast to the negative groups (PBS and ISCOMATRIX adjuvant). All groups that received antigen responded specifically against the rMSPs by Western blotting, showing the rMSP1a (60-105kDa), rMSP1b (100kDa), rMSP4 (47kDa), and rMSP5 (29kDa). Additional studies will have to be performed in cattle to evaluate the humoral and cellular mechanisms of this subunit vaccine and their possible use as protective vaccines against homologous and heterologous strains of A. marginale. 相似文献
95.
María del Mar Montiel‐Rozas Marco Panettieri Paula Madejn Engracia Madejn 《Land Degradation \u0026amp; Development》2016,27(3):620-629
The study of different natural carbon sinks has become especially important because of climate change effects. The restoration of contaminated areas can be an ideal strategy for carbon sequestration. The studied area was affected by toxic Aznalcóllar mine spill in 1998. Restoration process of the contaminated area was based, mainly, on the use of two organic amendments: leonardite (LE) and biosolid compost (BC). The objective of this study was to verify whether the application of these amendments promotes the long‐term carbon sequestration in this soil. Five treatments were established: untreated control, biosolid compost (doses 4 and 2) and leonardite (doses 4 and 2). The addition of amendments implied an improvement in soil quality that was directly related to the amendment dose: decrease in bulk density, increase in pH, higher respiration rates and an improvement in the stratification ratio. Dose‐dependent changes in the molecular composition of soil organic matter were shown by nuclear magnetic resonance analysis. Both amendments promoted carbon retention, although because of the low mineralization rates of soil organic matter in LE treatments, the carbon storage was higher. The dosage effect on the carbon balance was more important in LE treatments, whereas in the BC treatments, the balance was similar for both doses. Our findings suggest that LE4 significantly increased the total organic carbon and it was the most suitable treatment for long‐term carbon storage, because of its molecular composition rich in relatively stable aromatic and lignin‐derived compounds. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
96.
Paula Filomena Martins-Lopes Henrique Guedes-Pinto Olinda Pinto-Carnide John Snape 《Euphytica》2001,121(3):265-271
Barbela is an old Portuguese landrace of wheat that is highly genetically heterogeneous. Different Barbela populations when
subjected to aluminium stress show variable levels of tolerance. In order to study the inheritance of this character, doubled
haploid (DH) lines were developed. These DH were obtained by intergeneric crosses of 14 different lines of Barbela with maize.
During this process the efficiency of the technique was evaluated and suggestions for its improvement were obtained. Several
parameters were studied in the crosses: % of crossability, % of embryos per florets pollinated and % of embryos per seed set.
The different genotypes of Barbela showed significant variation for the parameters analysed. When the reciprocal crosses were
analysed, no differences were found, indicating that cytoplasm differences do not influence the parameters of DH production.
However, different spikelet positions (lower, middle and upper) gave highly significant differences in all parameters analysed.
Highest success frequencies were obtained for pollinated spikelets in the middle of the spike. This can indicate that concentrating
on the middle part of the spike can increase the frequency of DHs obtained using inter generic crosses of wheat with maize.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
97.
Paula Brown 《Asia Pacific viewpoint》2005,46(2):135-142
Abstract: This paper discusses my collaboration with Harold Brookfield in the study of Chimbu land and society. We began in 1958 at the Australian National University and worked together until 1965 in joint fieldwork and writing, and then collaborated occasionally after that. It began both of our professional contributions that continued throughout our professional careers. The work could never have been done by one person, either geographer or anthropologist. Our joint paper of 1990 may be the only multigenerational land study in anthropology/geography. Our long‐term study of the Mintima area is a constant reminder of the hazards of short‐sighted development projections. Brookfield always knew what he wanted to find out, and always constructed original methods of research and analysis. The Chimbu–Mintima maps were redrawn many times with many different measuring methods, new air photography and increasing precision. He always connected any specific study and report of work to general theory and would compare a wide range of related findings in other places. His work is a model of scientific method and its place in geographical theory. 相似文献
98.
Sugarcane leaves and calli from highly susceptible and resistant varieties to eyespot disease were used to evaluate the Drechslera sacchari toxin effect at different concentrations and incubation times by measuring electrolyte leakage. This expression of disease resistance was observed not only in the leaf but also in the callus. Furthermore, the growth of resistant calli MS medium supplemented with DS toxin, was higher when compared to the susceptible ones. The possibility of obtaining resistant somaclones is confirmed. 相似文献
99.
Pinto PC Evtuguin DV Pascoal Neto C 《Journal of agricultural and food chemistry》2005,53(20):7856-7862
The wood of Acacia mangium, a prominent fast-growing plantation species used in the pulp-and-paper industry and, so far, poorly investigated for its chemical structure, was submitted to a detailed characterization of its main macromolecular components. Lignin (28% wood weight) isolated by mild acidolysis and characterized by permanganate oxidation, 1H and 13C NMR, and GPC, showed a very low content of syringylpropane-derived units (S:G:H of 48:49:3), a high degree of condensation, a low content of beta-O-4 ( approximately 0.40-0.43 per C6) structures, and a Mw of 2230. Glucuronoxylan (14% wood weight) isolated by alkaline (KOH) or by dimethyl sulfoxide extraction was characterized by methylation analysis, 1H NMR, and GPC. About 10% of the xylopyranose (Xylp) units constituting the linear backbone were substituted at O-2 with 4-O-methylglucuronic acid residues. Almost half of the Xylp units (45%) were O-2 (18%), O-3 (24%) or O-2,3 (3%) acetylated. X-ray diffraction analysis of cellulose (46% wood weight), isolated according to the Kürschner-Hoffer method, showed a degree of crystallinity of 67.6%. 相似文献
100.
Oliveira CM Silva Ferreira AC Guedes De Pinho P Hogg TA 《Journal of agricultural and food chemistry》2002,50(7):2121-2124
This work describes a new potentiometric method to evaluate the resistance to oxidation of white wines. Reduction and oxidation titrations were made, and coefficient of variation obtained were 10.87 and 2.65%, respectively. The antioxidant powers of ascorbic acid (Aas) and sulfur dioxide (SO(2)) were evaluated by this method, SO(2) proving to be much less active in this respect than ascorbic acid. The two agents did not demonstrate any antioxidant synergy. A relationship between oxygen present and ascorbic acid was found by the proposed method (1 mmol of O(2) <--> 0.84 mmol of Aas). This method enables the distinction of different wines on the basis of their resistance to oxidation. 相似文献