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61.
Resistance to many arthropods, including Liriomyza species, is known to be present in accessions of Lycopersicon hirsutum (f. typicum or f. glabratum). From the cross L. esculentum cv. Moneymaker and L. hirsutum f. glabratum G1561 100 F2 plants were screened in a no-choice test for resistance to Liriomyza trifolii. The Bulked Segregant Analysis approach was used to find Random Amplified Polymorphic DNA markers linked to resistance. Two
markers were located on chromosome 2. Restriction Fragment Length Polymorphisms constructed a more detailed genetic linkage
map for part of chromosome 2. Kruskal-Wallis analysis showed that this chromosome harbored a Quantitative Trait Locus (QTL)
for number of pupae, number of mines and damage. At least one major QTL is essential for resistance and this QTL is located
on chromosome 2 nearby the location of the tomato probe TG451.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
62.
Antonino Galati Luciano Gristina Maria Crescimanno Ettore Barone Agata Novara 《Land Degradation \u0026amp; Development》2015,26(6):557-564
Evaluating the economic damage caused by soil erosion is important. In addition to increasing the awareness of the problem among farmers and policy makers, evaluation of the economic damage caused by erosion can promote the implementation of more sustainable soil management practices. In the present study, we describe a new approach to evaluate incentives for the adoption of agri‐environment measure (AEM) in degraded and eroded vineyards. To estimate this incentive, the replacement cost (RC) and the loss of income are calculated when the vineyard is managed with conventional tillage versus a cover crop (AEM). Our findings show that the incentive could range from the loss of income due to AEM adoption to the ecosystem service benefit (RCC − RCAEM). In our case study, the incentive ranged from 315 € ha−1 (loss of income) to 1,088 € ha−1 (ecosystem service benefit). Within this range, the incentive amount is determined according to efficiency criteria based on vineyard slope. We also present a conceptual model of public spending efficiency that should help policy makers decide how to allocate the incentives so as to maximize the economic return associated with ecosystem services. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
63.
Andrés Calderín García Orlando Carlos Huertas Tavares Dariellys Martínez Balmori Vitor dos Santos Almeida Luciano Pasqualoto Canellas José María García-Mina Ricardo Luis Louro Berbara 《Journal of Soils and Sediments》2018,18(4):1365-1375
Purpose
The use of humic substances (HS) in agriculture is beneficial and has positive environmental impacts. However, to optimize the use of HS possible links between their structural characteristics and bioactivity must be shown. The goal of this study is to evaluate the bioactivity of different humic fractions extracted from vermicompost (VC) in rice plants and to shed light to possible structure-function relationships.Materials and methods
Humic-like fractions were obtained from cattle manure vermicompost processed by African nightcrawlers (Eudrilus eugeniae spp.). Humic-like acid fraction using only water as extractor (HLAw), HLA fraction extracted following the International Humic Substances Society (IHSS) recommended method, and the solid residue (humified residual (HR)) after extraction of HLA were characterized using complementary chemical, physic, and spectroscopic technics (elemental composition, UV-Vis and Fourier transform infrared spectroscopy (FTIR) spectroscopies, 13C-CP MAS NMR, and MEV). Biological activity of the three HS was conducted in growth chambers and measured in roots using WinRhizo Arabidopsis software. Principal component analysis (PCA) was used to find a grouping pattern between the structural variables evaluated and the obtained root parameters.Results and discussion
Differences were found in elemental composition among HS with larger C/N ratio in HR than in HLA and HLAw. HLA and HLAw FTIR spectra showed carboxyl band at 1714.66 cm?1 better resolved than in HR. Bands at 1642 cm?1 (amide I) and 1510 cm?1 (lignin), were better resolved in HLA. 13C-NMR showed the following order of aromaticity: HLA > HLAw > HR. For HLAw bioactivity, the structures CAlkyl-H,R, CC=O, and CCOO-H,R correlated with the number and growth of smaller root. The aromatic CAr-H,R, CAr-O,N, and aliphatic CAlkyl-O,N, CAlkyl-O, and CAlkyl-di-O structures in HLA, correlated with larger roots growth. HR also stimulated root growth and development in rice plants.Conclusions
Aliphatic and oxygenated structures in HLAw showed a relation with induction of initial root emissions, whereas the presence of aromatic compounds in HLA was related with root growth stimulation activity. Higher concentration of HLAw was necessary to produce an equivalent stimulus compared with HLA; it could indicate that, although both fractions showed similar types of structures in their composition, differences in the predominant structures may be determining different effects on the root.64.
Summary The evaluation aimed at identifying landrace genotypes adapted to the rather unfavourable growing conditions of durum wheat in Sicily, to be used as parental material in a breeding programme. The trial was carried out in three seasons experiencing varying climatic conditions, and included 75 landraces, 25 of which were selected under severe drought in Syria. Wide differences were observed for most traits among genotypes and seasons of evaluation. Yields of the best performing entries identified in each season never significantly differed from that of the best check variety. The top-yielding landraces were consistently better than the remaining entries for the three yield components, viz. number of spikes per plant, number of kernels per spike and mean kernel weight. In the driest season they were also significantly earlier in heading, confirming the importance of earliness under drought. An analytical breeding approach relying on an array of morpho-physiological traits as selection criteria did not seem appropriate for the given environment, as the variable stress level enhanced the importance of specific traits under specific situations. The genotypic response was largely season-specific. Nonetheless, five landraces were in the best group in all seasons. The selection made in Syria also appeared somewhat effective in Sicily, particularly in the less favourable seasons. 相似文献
65.
Camila Pegoraro Liliane Marcia Mertz Luciano Carlos da Maia Cesar Valmor Rombaldi Antonio Costa de Oliveira 《Journal of Crop Science and Biotechnology》2011,14(2):85-95
Abiotic and biotic stress conditions cause extensive losses to maize production, mainly due to protein dysfunction in these
conditions. In higher plants, the occurrence of heat-shock proteins (HSPs) in response to different environmental stresses
is a universal phenomenon and has been well documented. Many studies have demonstrated that most HSPs are involved in many
regulatory pathways, act as molecular chaperones for other cell proteins, and have strong cytoprotective effects. Although
many functional roles for HSPs are known, the mechanisms for these multiple functions are not entirely understood. Here we
reviewed the correlation among HSP genes/proteins and plant tolerance, especially maize, in different environmental stresses. Due to the low availability of
information regarding the expression of HSP genes in response to different stresses in maize, we decided to mine databases in order to generate new insights related
to this topic. 相似文献
66.
Luciano de O. Garcia Alexssandro G. Becker Mauro A. Cunha Bernardo Baldisserotto Carlos E. Copatti Daiani Kochhann 《Journal of the World Aquaculture Society》2011,42(3):399-405
The aim of this study is to determine the effect of (1) different pH levels (5, 6, 7, 8, and 9) with water hardness 20 mg/L CaCO3 and (2) pH 5 and 7 with varying water hardnesses (20, 60, and 120 mg/L CaCO3) on the intensity of infection by Ichthyophthirius multifiliis in fingerlings of the silver catfish, Rhamdia quelen. In Experiment 1, the lowest and highest mortality rates were observed in fingerlings exposed to pH 5 and 9, respectively; in Experiment 2, fish kept at pH 5 and 7 with hardness 20 mg/L CaCO3 showed significantly lowest and highest cumulative mortality, respectively, than those maintained in other conditions. The lowest intensity of trophonts/fingerling was observed at pH 5 and hardness 20 mg/L CaCO3 in both experiments. We conclude that infection by I. multifiliis is less severe in silver catfish maintained at pH 5 and hardness 20 mg/L CaCO3. High water hardness led to an increased intensity of trophonts and decreased survival in silver catfish kept at pH 5, but decreased intensity of trophonts and improved survival when the fish were kept at pH 7. 相似文献
67.
68.
Leandro Santos Costa Felipe Guedes de Araújo Renan Rosa Paulino Luciano Jos Pereira Edgar Junio Damasceno Rodrigues Paula Adriane Perez Ribeiro Priscila Vieira Rosa 《Aquaculture Research》2019,50(9):2371-2379
Although daily variations in drug pharmacokinetics have been reported for a variety of teleost species, the influence of this daily variation on the cortisol response following anaesthesia remains poorly understood. To address this, two experiments were performed. The first experiment described the daily patterns of cortisol and glucose secretion in tilapia (Oreochromis niloticus). The second experiment investigated how the timing of anaesthetic administration (specifically at mid‐light [ML] or at mid‐dark [MD]) affects the induction and recovery times and plasma cortisol and glucose levels of juvenile Nile tilapia exposed to benzocaine, clove oil or tricaine methanesulphonate (MS‐222). The results revealed that the effect on the stress response associated with the moment when anaesthesia took place (ML or MD) varied according to the treatment (p < 0.05). Cortisol levels were significantly higher at ML for MS‐222 (ML = 116.23 ± 25.55; MD = 48.25 ± 22.33 ng/dl) (p < 0.05) and clove oil (ML 59.73 ± 14.27; MD 38.26 ± 12.07 ng/dl) (p < 0.05), whereas no significant differences were found between ML and MD cortisol levels for the control treatment (ML = 72.91 ± 18.42; MD = 64.80 ± 10.68 ng/dl) (p > 0.05) or in the benzocaine‐treated group (ML = 38.7 ± 4.90; MD = 38.60 ± 3.69 ng/dl) (p > 0.05). The highest plasma cortisol level in ML was found in the MS‐222‐treated group. All the tested anaesthetics had similar cortisol levels at MD (p > 0.05). 相似文献
69.
Daniel Pinto Lucas Pellegrin Lilian Fiori Nitz Sílvio Teixeira da Costa Jos Maria Monserrat Luciano Garcia 《Aquaculture Research》2019,50(10):3017-3027
In this study, the influence of temperature variation on the blood and oxidative stress parameters of pacu Piaractus mesopotamicus juveniles was evaluated. Fish were subjected to gradual changes of temperature, over 5 days, by 24°C until reaching to experimental temperatures 18, 21, 24 (control), 27 and 30°C. There were significant differences (p < .05) in glucose and lactate of blood in both the haematological relationships and oxidative stress parameters. Glucose levels increased at 30°C and decreased at 21°C. Lactate levels were highest at 18°C. While the haematocrit was higher at all altered temperatures, haemoglobin levels decreased at 21°C and increased at 30°C, causing alterations in haematimetric indices. In the liver, glutathione‐S‐transferase (GST) activity was reduced at 18°C while antioxidant capacity against peroxyl radicals (ACAP) was highest at 30°C. Thiobarbituric acid reactive substances (TBARS) increased at 18, 21 and 27°C. In the muscle, ACAP decreased at 27 and 30°C and TBARS increased at 30°C. The results indicate that the species shows sensitivity to temperature variations. Accordingly, we conclude that with short‐term temperature variations >3°C, it is possible to induce higher alterations in the observed parameters in pacu juveniles. 相似文献
70.
Sousa Andria Gama Pacheco Acácio H. B. Siqueira-Pinto Gilson A. dos Reis Gleika T. J. Fugimura Michelle M. S. Vaz Luciano J. Marcusso Paulo F. Ramos-Espinoza Fernando C. da Silva Claudiano Gustavo 《Aquaculture International》2021,29(3):977-988
Aquaculture International - The objective of the present study was to evaluate the action of benzocaine and eugenol over anesthesia stages and the use of three anticoagulants (ethylenediamine... 相似文献