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171.
Use of the microalga Nannochloropsis occulata in the rearing of newborn longsnout seahorse Hippocampus reidi (Syngnathidae) juveniles 下载免费PDF全文
Roberta Cecília Silfrônio Mélo Lília Pereira de Souza Santos Ana Paula Morais Brito Adriana de Andrade Gouveia Clebson Marçal Ronaldo Olivera Cavalli 《Aquaculture Research》2016,47(12):3934-3941
The aim of this study was to evaluate the effect of microalgae on the rearing of newborn juveniles of the longsnout seahorse, Hippocampus reidi. Two treatments in three replicates were tested over a 15‐day period: with and without the addition of the microalgae Nannochloropsis oculata at a concentration of 2.02 ± 0.44 × 106 cells mL?1. At each replicate, beginning on the second day of life, 120 H. reidi juveniles (stocking density of 3 ind L?1) were fed the offspring of the benthic copepod Tisbe biminiensis (100 copepod cm?2) together with newly hatched Artemia nauplii (3.8 mL?1). From the sixth day of life, enriched Artemia metanauplii replaced newly hatched Artemia nauplii. After 15 days, the H. reidi individuals were counted, measured and weighed. Mean survival was significantly greater in the microalgae treatment (76.42 ± 5.07%) than in the treatment with no microalgae (25.44 ± 6.91%). Moreover, total length, height and dry weight were significantly larger in the microalgae treatment. Thus, the addition of microalgae increases the growth and survival of H. reidi juveniles fed T. biminiensis and Artemia. The higher growth and survival of H. reidi juveniles was not related to the larger ingestion rates but probably to the nutritional improvement of the live feeds or to the probiotic effect. The protocol developed for rearing H. reidi juveniles resulted in a high survival, and represents an advance in the farming of this species. 相似文献
172.
Alicia Pérez-Hernández Mario González Celedonio González Nélida Brito 《Plant pathology》2020,69(5):807-817
BcIEB is a small protein secreted by the phytopathogenic fungus Botrytis cinerea that is recognized as a pathogen-associated molecular pattern (PAMP) by plants. This activity is mapped to a highly conserved region of 35 amino acids, the peptide ieb35. Moreover, it has been shown that the protein and the peptide induce systemic resistance to B. cinerea after their infiltration into tobacco leaves. In this work, the possible use of BcIBE1 or ieb35 as plant protective agents has been tested. Tobacco plants were sprayed, infiltrated, or treated at the seedling stage with the protein or the peptide, and plant susceptibility to pathogens with different lifestyles was then studied at various times after treatment. The results showed that both BcIEB1 and ieb35 caused a similar reduction in the lesion sizes caused by B. cinerea and in colonization by Pseudomonas syringae pv. tabaci (reduced by c. 30% and c. 40%, respectively), independently of the treatment type. In addition, the number of B. cinerea inoculations leading to successful infections was also reduced in plants infiltrated or sprayed with BcIEB1/ieb35. The defence-related genes PR1a, NPR1, and osmotin ap24 were all induced by the protein and the peptide. BcIEB1, and especially ieb35, may be considered as a potential environmentally friendly treatment to increase plant resistance to pathogens. 相似文献
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Claudia Brito Silva Márcia Azanha Ferraz Dias de Moraes José Paulo Molin 《Precision Agriculture》2011,12(1):67-81
Precision agriculture (PA) technologies are being applied to crops in Brazil, which are important to ensure Brazil’s position in agricultural production. However, there are no studies available at present to indicate the extent to which PA technologies are being used in the country. Therefore, the main objective of this research was to investigate how the sugar-ethanol industry in São Paulo state, which produces 60% of the domestic sugarcane, is adopting and using these techniques. For this purpose, primary data were used, which were obtained from a questionnaire sent to all companies operating in the sugar-ethanol industry in the region. The aim was to determine to what extent these companies are adopting and using PA technologies, and also to promote a more in-depth discussion of the topic within the sugar-ethanol industry. Information was obtained on the features of the companies, on sources of information that they use for adopting these technologies, on their impacts on these companies and on obstacles hindering their adoption. The main conclusions of this research suggest that companies that adopt and use PA practices reap benefits, such as managerial improvements, higher yields, lower costs, minimization of environmental impacts and improvements in sugarcane quality. 相似文献
175.
Anthony D. M. Glass Dev T. Brito Brent N. Kaiser Herbert J. Kronzucker Anshuman Kumar Mamaru Okamoto S. R. Rawat Mohammed Y. Siddiqi Salim M. Silim Joseph J. Vidmar Degen Zhuo 《植物养料与土壤学杂志》2001,164(2):199-207
Physiological methods, especially the use of isotopes of N, have allowed for the detailed characterizations of the several putative transport systems for nitrate and ammonium in roots of higher plants. In the last decade, the cloning of genes that appear to encode both high- and low-affinity transporters represent major advances, as well as substantiating the inferences based on earlier physiological methods. Nevertheless, the unexpected plethora of genes that have been identified now presents even greater challenges, to resolve their individual functions and to attempt to place these functions in a whole plant/environmental context. 相似文献
176.
Luis Otavio Brito Luis Alejandro Vinatea Arana Roberta Borda Soares William Severi Rayzza Helena Miranda Suzianny Maria Bezerra Cabral da Silva Maria Raquel Moura Coimbra Alfredo Olivera Gálvez 《Aquaculture International》2014,22(5):1649-1664
A 28-day indoor trial was conducted to evaluate the water quality, phytoplankton composition and growth of Litopenaeus vannamei in an integrated biofloc system with Gracilaria birdiae and Gracilaria domingensis. The experimental design was completely randomized with three treatments: control (shrimp monoculture); SB (shrimp and G. birdiae) and SD (shrimp and G. domingensis), all with three replicates. Random sampling was done (6 % of total population per experimental unit) to confirm white spot syndrome Virus (WSSV) infection using nested-PCR analysis due to suspicion of presence of the virus in the experiment (treatment and control groups). Shrimp L. vannamei (2.63 ± 0.10 g) were stocked in experimental tanks at a density of 425 shrimp m?3, and the Gracilaria was stocked at a biomass of 2.0 kg m?3. Shrimp mortality began in both the experimental and control groups at 10 days of culture. The integrated biofloc system (shrimp and seaweed) increased settleable solids (by 26–52 %); final weight (by 6–21 %); weekly growth (by 17–43 %); weight gain (by 17–43 %); specific growth rate (by 16–36 %); and yield (by 5–7 %) and decreased feed conversion ratio (by 21–28 %) and Cyanobacteria density about 16 % as compared to the control (shrimp monoculture). The use of red seaweed Gracilaria in an integrated biofloc system can enhance shrimp growth and reduce Cyanobacteria density in the presence of WSSV. 相似文献
177.
Using continuously recorded trunk diameter fluctuations for estimating water requirements of lemon trees 总被引:1,自引:0,他引:1
Maria Fernanda Ortuño J. J. Brito W. Conejero Y. García-Orellana A. Torrecillas 《Irrigation Science》2009,27(4):271-276
Adult Fino lemon trees (Citrus limon L. Burm. fil.) grafted on sour orange (Citrus aurantium L.) and irrigated above their crop water requirements (T0 treatment) were compared with plants where water was applied according
to maximum daily trunk shrinkage (MDS) (T1 treatment), in order to maintain MDS signal intensity [actual (T1) MDS/control
(T0) MDS] threshold values close to unity. When MDS signal intensity on at least 2 of 3 consecutive days did not exceed the
signal intensity threshold value, irrigation was reduced by 10%. In contrast, when the MDS signal intensity on at least 2
of 3 consecutive days exceeded the threshold value, the irrigation rate was increased by 10%. The results indicated that lemon
tree irrigation scheduling can be based on MDS measurements, avoiding the appearance of any plant water stress situation without
affecting yield or fruit quality. Also, the cumulative amounts of applied water in T1 plants can be considered as an estimate
of lemon tree water requirements, because they were only 9% above the estimated crop evapotranspiration (ETc) and drainage
did not occur. Nevertheless, to improve the precision of irrigation management, some changes in the irrigation protocol for
periods of variable evaporative demand were proposed: for instance, increasing the irrigation scheduling frequency and/or
using changes in the daily irrigation rate higher than those proposed in the protocol. 相似文献
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179.
MBS de Brito MAR Feliciano LN Coutinho RR Uscategui APR Simões MC Maronezi VT de Almeida RM Crivelaro B Gasser L Pavan WR Russiano 《Reproduction in domestic animals》2015,50(5):730-734
The objective was to characterize the vascular patterns of testicular blood flow of adult cats, measuring the systolic velocity (SV), diastolic velocity (DV), resistance index (RI), gate time (wash‐in) peak enhancement and output time (wash‐out) of the contrast and addition of tissue fill characteristics. Forty‐five adult cats were selected, and the echotexture, echogenicity, size, contours and margins of testicles were assessed via ultrasound. By Doppler were evaluated the blood flow and determined of vascular index in testicular artery (SV, DV and RI) and via contrast‐enhanced ultrasonography determine the time for phases: wash‐in, wash‐out and peak enhancement. Sonographic findings presented normal. Testicular artery was observed in the spermatic cord with tortuous patter and showed monophasic‐patterned waves and low vascular resistance and with systolic peak evident. Values of indices vascular were as follows: SV = 6.73 cm/s, DV = 2.8 cm/s and RI = 0.54 for left testicles; and SV = 6.23 cm/s, DV = 2.77 cm/s and RI = 0.53 for right testicles. Contrast filled the subcapsular vascular structures and after a few seconds, a homogeneous moderate enhancement of the parenchyma, with parenchymal vessels still distinguishable and after the peak phase, a rapid homogeneous decrease in echogenicity. Values of time for contrast‐enhanced ultrasonography were as follows: wash‐in = 8.78 s, peak enhancement = 21.62 s and wash‐out = 75.36 for left testicles; and wash‐in = 10.76 s, peak enhancement = 21.50 s and wash‐out = 81.81 for right testicles. Doppler and contrast‐enhanced ultrasonography of the testicles in healthy adult cats was easily implemented and may provide baseline data for this organ to allow the use of these techniques as a diagnostic tool for evaluating testicular abnormalities in sick cats. 相似文献
180.
A. Pellegrineschi S. McLean M. Salgado L. Velazquez R. Hernandez R.M. Brito M. Noguera A. Medhurst D. Hoisington 《Euphytica》2001,119(1-2):135-138
Plant breeders are always interested in new genetic resources. In thepast, the sources have been limited to existing germplasm. Geneticengineering now provides the opportunity for almost unlimited strategies tocreate novel resources. As a first stage, the Applied Biotechnology Center(ABC) at CIMMYT developed a method for the mass production of fertiletransgenic wheat (Triticum aestivum L.) that yields plants ready fortransfer to soil in 13–14 weeks after the initiation of cultures, and, over thecourse of a year, an average production of 5–6 transgenic plants per day.CIMMYT elite cultivars are co-bombarded with marker gene and a gene ofinterest with co-transformation efficiencies around 25–30%. The reliabilityof this method opens the possibility for the routine introduction of novelgenes that may induce resistance to diseases and abiotic stresses, allow themodification of dough quality, and increase the levels of micronutrientssuch as iron, zinc, and vitamins. The first group of genes being evaluatedby the ABC are the pathogenesis related (PR) proteins, such as thethaumatin-like protein (TLP) from barley, chitinase, and 1–3-glucanase. Stable integration of the genes in the genome andinheritance in the progeny were determined by phenotypical analyses thatchallenged the plants against a wide range of pathogens. Using these genes,we have recovered more than 1200 independent events (confirmed byPCR and Southern blot analyses) that show responses to the pathogens thatrange from tolerance to hypersensitive reactions. The quantity andanti-fungal activity of the endogenous thaumatin-like proteins were analyzedin T1 and T2 progeny plants. Western blot analyses showeddifferent protein patterns of the wheat endogenous TLPs. Preliminary resultsindicated that some patterns increased the resistance of transgenic wheatplants to Alternaria triticina. This relationship is being furtherinvestigated. 相似文献