Genetic Resources and Crop Evolution - The development of segregating populations in papaya allows the development of new high fruit yield and excellent fruit quality pure line or hybrid cultivars.... 相似文献
Here, we presented new insights of the development of poly(lactic-co-glycolic acid) nanoparticles containing turmeric compounds (turmeric-PLGA-NPs) using emulsion-solvent evaporation method. The nanoparticulate system was characterized by size, zeta potential, morphology, release profile, partition parameter, stability and encapsulation efficiency (%EE). Antioxidant activity studies were also evaluated. The Korsmeyer-Peppas model (Mt/M∞ vs. t) was used to determine the release mechanisms of the studied system. Our results demonstrated the emulsion-solvent evaporation method was shown advantageous for producing turmeric-PLGA-NPs in the range of 145 nm with high homogeneity in size distribution, zeta potential of ?21.8 mV and %EE about 72%. Nanoparticles were stable over a period of one month. In vitro study showed a release of curcumin governed by diffusion and relaxation of the polymeric matrix. The partition parameter of the extract in relation to blank-PLGA-NPs was 0.111?±?0.008 M?1, indicating a low affinity of curcumin for the polymer matrix. Antioxidant ability of the turmeric-PLGA-NPs in scavenging the radical 2,2-azinobis (3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) was inferior to free turmeric extract and showed a concentration and time-dependent profile. The study concluded that PLGA nanoparticles are potential carriers for turmeric extract delivery.
The leafminer Liriomyza sativae (Diptera: Agromyzidae) stands out as the main plant health problem in melon in the Northeast region of Brazil, which is the main region for production and export of the fruit. Genetic resistance of plants is an important strategy in management of this pest. The plant BAGMEL 56-R was selected as a new source of resistance to L. sativae through antibiosis; this resistance is characterized by the death of larvae soon after they begin feeding on the leaf mesophyll; the result is leaf mines that are small and insignificant in terms of yield reduction. Lines with contrasting levels of resistance were obtained from the progenies of this source of resistance through successive self-pollinations, conducted by the pedigree breeding method. Through the segregation pattern of the progenies and the test cross, the genetic nature of resistance was determined; one gene with complete dominance conditions resistance. The name Liriomyza sativae resistance and the symbol Ls are suggested to represent this new gene. In addition, through a non-preference test with lines in contrast for antibiosis and the susceptible hybrid ‘Goldex’, the presence of antixenosis was observed in this source of resistance. Probably, these different types of resistance in the source BAGMEL 56-R are associated with distinct defense mechanisms. Therefore, with this new source, introgression of resistance to L. sativae in elite lines or commercial hybrids of melon is possible. 相似文献
Behavioral responses, blood markers, and fillet properties were investigated after silver catfish exposure to different electric field strengths, frequency, and duration of electric current in the preslaughter stunning. All combinations of electric fields and frequencies were able to stun fish. Longer apparent stun was obtained at the intermediate electrical frequencies. High electric field strength detracted the texture of fillets. At least 5 s was required to stun fish, and longer exposure to electrical current did not prolong the apparent stun or damage fillet properties. Results indicate that silver catfish are relatively resistant to electronarcosis. 相似文献
The possibility of using near-infrared spectroscopy (NIRS) for the authentication of wild European sea bass ( Dicentrarchus labrax ) was investigated in this study. Three different chemometric techniques to process the NIR spectra were developed, and their ability to discriminate between wild and farmed sea bass samples was evaluated. One approach used spectral information to directly build the discrimination model in a latent variable space; the second approach first used wavelets to transform the spectral information and subsequently derived the discrimination model using the transformed spectra; in the third approach a cascaded arrangement was proposed whereby very limited chemical information was first estimated from spectra using a regression model, and this estimated information was then used to build the discrimination model in a latent variable space. All techniques showed that NIRS can be used to reliably discriminate between wild and farmed sea bass, achieving the same classification performance as classification methods that use chemical properties and morphometric traits. However, compared to methods based on chemical analysis, NIRS-based classification methods do not require reagents and are simpler, faster, more economical, and environmentally safer. All proposed techniques indicated that the most predictive spectral regions were those related to the absorbance of groups CH, CH(2), CH(3), and H(2)O, which are related to fat, fatty acids, and water content. 相似文献