3 resultados para LOPEZ, ESTANISLAO
em eResearch Archive - Queensland Department of Agriculture
Resumo:
A cross-sectional study was conducted between October 2011 and March 2012 in two major pig producing provinces in the Philippines. Four hundred and seventy one pig farms slaughtering finisher pigs at government operated abattoirs participated in this study. The objectives of this study were to group: (a) smallholder (S) and commercial (C) production systems into patterns according to their herd health providers (HHPs), and obtain descriptive information about the grouped S and C production systems; and (b) identify key HHPs within each production system using social network analysis. On-farm veterinarians, private consultants, pharmaceutical company representatives, government veterinarians, livestock and agricultural technicians, and agricultural supply stores were found to be actively interacting with pig farmers. Four clusters were identified based on production system and their choice of HHPs. Differences in management and biosecurity practices were found between S and C clusters. Private HHPs provided a service to larger C and some larger S farms, and have little or no interaction with the other HHPs. Government HHPs provided herd health service mainly to S farms and small C farms. Agricultural supply stores were identified as a dominant solitary HHP and provided herd health services to the majority of farmers. Increased knowledge of the routine management and biosecurity practices of S and C farmers and the key HHPs that are likely to be associated with those practices would be of value as this information could be used to inform a risk-based approach to disease surveillance and control. © 2014 Elsevier B.V.
Resumo:
The development of a more efficient in vitro regeneration system for somatic embryos (SEs) of avocado (Persea americana) would facilitate the development of new superior cultivars for this valuable horticultural crop. In this study, we report a new and efficient method for maintenance and regeneration of avocado SEs. Avocado SEs of four cultivars remained healthy and viable in vitro for 11 months on a medium used for mango somatic embryogenesis, compared with 3-4 months on Murashige and Skoog medium. Various supplements and media modifications were investigated to improve the low conversion rate of regenerated plants from avocado SEs reported previously. The one-step system for regeneration of white-opaque somatic embryos (WOSEs) used solid medium only over a period of 12-14 weeks (sub-culturing every 6 weeks). Addition of praline and glutamine improved the total regeneration from 0 to 17.5% and 10.5%, and plant/shoot recovery from 0 to 12.5% and 5%, respectively. A two-step culture system involving the transfer of WOSEs of cultivar 'Reed' after 6 weeks on solid to liquid medium for 12-15 days as an intermediate step, followed by subculturing again onto solid medium for 6 weeks improved total regeneration to 29% and plant/shoot recovery to 18.3 from 0% when regenerated by subculturing on solid medium only. Supplementation with proline in the solid as well as liquid medium in the two-step culture system at 0.4 g/L increased total regeneration to 35% and plant/shoot recovery to 20%. We were able to achieve highest regeneration using glutamine at 1 g/L in the two-step culture system in terms of both total regeneration (58.3%, including 43.3% bipolar regeneration) and plant/shoot recovery (36.7%) rates, which were significantly higher than in any other treatment investigated. (C) 2013 Elsevier B.V. All rights reserved.
Resumo:
The ethylene biosynthesis inhibitor, 1-methylcyclopropene (1-MCP), has been commercially used to extend the storage life of European pear fruit and to allow shipment to distant markets. However, the influence of 1-MCP on the ability of fruit to ripen to an acceptable sensory quality has not been investigated in 'Bartlett' pear, one of the most aromatic of pear fruit. In the current study, early-, mid- and late-season 'Bartlett' pear fruit were treated with 0.6μLL-1 1-MCP at 0°C for 24h, 100μLL-1 ethylene at 20°C for 24h, or untreated before immediate transfer to 20°C for ripening until eating soft (13N firmness). Fruit from each treatment were subjected to objective and sensory quality evaluation once ripe. Sensory quality showed differences related to harvest maturity; the importance of harvest maturity depended on the treatment. Treatment with 1-MCP effectively slowed fruit ripening and therefore extended postharvest life, but also resulted in fully ripened pears with more desirable sensory traits, as compared with ethylene-treated and untreated pears. The enhanced sensory quality was related to higher sweetness, juiciness and pear aroma and reduced fermented aroma, gritty texture and tart taste. In addition, the sensory profiles of 1-MCP-treated pears were more stable among fruit from the three harvest dates than the ethylene-treated pears, which exhibited very different sensory profiles between early- and late-season fruits. © 2015 Elsevier B.V.