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21.
Torres Andrea Basurto Francisco Navarro-Ocana Arturo 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(4):531-537
Plant Foods for Human Nutrition - Sweet potato is one of the oldest crops cultivated in Mexico, and Mesoamerica is considered as a region with the greatest diversity of this species. Therefore, the... 相似文献
22.
David Ramos‐Vidales Gabriela Gmez‐Verduzco Arturo Cortes‐Cuevas Juan Carlos del Río‐García Sergio Fernndez‐Tinoco Silvestre Chrraga‐Aguilar Ernesto vila‐Gonzlez 《Journal of animal physiology and animal nutrition》2019,103(5):1484-1491
This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals. 相似文献
23.
Spread of the yellow‐legged hornet Vespa velutina nigrithorax du Buysson (Hymenoptera: Vespidae) across Northern Spain 下载免费PDF全文
A. Goldarazena I. P. de Heredia P. Romon J. C. Iturrondobeitia M. Gonzalez S. Lopez 《EPPO Bulletin》2015,45(1):133-138
The yellow‐legged hornet Vespa velutina nigrithorax du Buysson (Hymenoptera: Vespidae) is an Asian native species which has now established in parts of Europe. Since its detection in France in 2005 it has spread quickly across the country and also spread to the Iberian Peninsula. This paper compiles the most recent data about its spread and distribution on the Spanish mainland. The efficacy of using Véto‐Pharma© traps as a control method is also discussed. 相似文献
24.
Franklin H. Rocha Francisco Infante Alfredo Castillo Guillermo Ibarra-Nu?ez Arturo Goldarazena Joe E. Funderburk 《Journal of insect science (Online)》2015,15(1)
A field survey was conducted in Ataulfo mango (Mangifera indica L.) orchards in Chiapas, Mexico, with the objective of determining the natural enemies of the Frankliniella complex species (Thysanoptera: Thripidae). Seven species of this genus feed and reproduce in large numbers during the mango flowering. Two representative orchards were selected: the orchard “Tres A” characterized by an intensive use of agrochemicals directed against thrips, and the orchard “La Escondida” that did not spray insecticides. During mango flowering, five inflorescences were randomly collected every 5 d in both orchards, for a total of 18 sampling dates. Results revealed the presence of 18 species of arthropods that were found predating on Frankliniella. There were 11 species in the families Aeolothripidae, Phlaeothripidae, Formicidae, Anthocoridae and Chrysopidae; and seven species of spiders in the families Araneidae, Tetragnathidae, and Uloboridae. Over 88% of predators were anthocorids, including, Paratriphleps sp. (Champion), Orius insidiosus (Say), Orius tristicolor (White), and O. perpunctatus (Reuter). The orchard that did not spray insecticides had a significantly higher number of predators suggesting a negative effect of the insecticides on the abundance of these organisms. 相似文献
25.
Dry forests represent the most endangered ecosystem in tropical regions and continue to be one of the most sought after environments for human colonization, development and production. In spite of this, dry forests are one of the least well studied tropical habitats. This special issue is dedicated to reviewing much of the information that exists about tropical dry forest in the Americas. The introduction summarizes the articles presented herein, highlighting management strategies that are suggested throughout the special issue that may be useful for conserving tropical dry forest environments. 相似文献
26.
Rotacio Gravoso Eduardo Mangaoang Maria Anabelle Gerona Arturo Pasa Steve Harrison 《Small-Scale Forestry》2009,8(3):275-287
In the Philippines, only a few farmers and plantation owners register their tree farms with the Department of Environment
and Natural Resources (DENR), the office in charge of tree registration. One of the major reasons is their lack of knowledge
of government policy on tree registration. To help improve the flow of information and understanding of tree registration
policies among smallholder tree farmers and other stakeholders, a Primer on Tree Registration, Harvesting, Transport and Marketing Policies on Private Land was developed. Produced through the participation of stakeholders, including tree farmers, the DENR, and local government
officers, police, and timber dealers, the Primer is highly visual and has been released in English as well as Waray–Waray
and Cebuano dialects. This paper reports findings of focus group discussions conducted to gauge user reactions to the Primer.
The Primer was considered as a valuable source of information about tree registration policies. Aside from being comprehensible,
FGD participants found it attractive, perceived it to be intended for them and free from content that confused them. However,
farmers suggested that illustrations need to be improved by making the persons portrayed more presentable and reflective of
their actual tree farm operations. Participants said that aside from the Primer, the flow of information on tree registration
policies could be improved through the use of multi-media including posters, radio broadcasts, and presentation in seminars
for farmers. 相似文献
27.
Shikha Singh Nathan Brandenburg Laurent Ahiablame Arturo Gonzalez Jeppe Kjaersgaard Todd P. Trooien Sandeep Kumar 《Water, air, and soil pollution》2017,228(10):389
Manure application on frozen soil, which is a common practice in the upper Midwest of USA, results in degraded soil and water quality. During snowmelt or precipitation events, water runoff carries nutrients into nearby streams and impairs the water quality. There is a need, therefore, to identify improved management of manure application in the soils. This study was conducted to assess water quality impacts associated following manure application during winter months when soil is completely covered with snow. The study site included three watersheds, named south (SW), east (CW), and north (NW) managed with a corn (Zea mays L.)-soybean (Glycine max L.) rotation located in South Dakota. The SW and NW were used as treatment, and CW as the control watershed. The treatments included manure application on the upper half of the SW and lower half of the NW, and CW received no manure application. This study showed that manure improved soil properties including infiltration rate and organic matter. Nitrogen and phosphorus losses in the surface runoff were higher from NW compared to that of SW. The CW had similar nutrient losses compared to the NW with slight differences. It can be concluded that maintaining a setback distance can help in improving the environmental quality as well as managing the agricultural wastes during the winter months. 相似文献
28.
Aleurotrachelus socialis is one of the most important pests of cassava (Manihot esculenta Crantz) in the Neotropics. In Colombia, high whitefly populations can reduce crop yields by 79%; and although the farmers intensify the use of insecticides, this practice is highly contaminating, costly and leads to the development of resistance in the insect. An alternative for managing whitefly populations is to develop genetically resistant varieties. Wild parents of Manihot are a useful source of genes against pests for the cultivated species of cassava. Based on prior research that showed the existence of moderate-to-high levels of resistance to A. socialis in Manihot flabellifolia, a wild species of cassava, this study was proposed to characterize this new source of resistance, evaluating the biology and demographics of A. socialis on eight accessions of M. flabellifolia, a susceptible check (CMC-40) and a resistant (MEcu72) check. The averages of A. socialis longevity and fecundity on the accessions were not significantly different to MEcu72, but different from CMC-40 (P < 0.05). Development time was not significantly different, ranging from 35–40 days on accessions and MEcu72 and 33.5 days on CMC-40 (P < 0.05). In contrast, the population growth rate (rm) was significantly lower on the M. flabellifolia accessions, with Fla 61 standing out with a growth rate 98 and 99% less than that obtained on MEcu72 and CMC-40, respectively. Once the resistant levels have been identified to A. socialis on the M. flabellifolia accessions, interspecific crosses of M. esculenta subsp. M. flabellifolia and backcross programs could be developed to incorporate the desirable characteristics from the wild relatives into elite progenitors of M. esculenta. 相似文献
29.
Arturo Carabalí James Montoya-Lerma Anthony C Belloti Martin Fregene Gerardo Gallego 《农业科学学报》2013,12(12):2217-2228
Genes resistant to Aleurotrachelus socialis were transferred to the F1 from the interspecific hybrid wild species of Manihot flabellifolia to M. esculenta and two advanced generations of backcrosses (BC1 and BC2). We characterized the resistance of A. socialis transferred to BC2 parents (CW67-160, CW67-130, CW67-44), MTAI-8 (BC1), resistant (CMB9B-73) and susceptible (CMB9B-104) genotypes from contrasting pools, and resistant (MEcu-72) and susceptible (CMC-40) genotypes. Whitefly demography and biology were evaluated. SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations (BC2). Results showed that although female survival time was similar on all hosts, the lowest averages of longevity, fecundity and oviposition rate were observed in the resistant control MEcu-72, only being significantly similar to the parent CW67-130. When the BC1 and BC2 populations were compared, it was found that A. socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130, expressing the highest levels of resistance to the whitefly. Ten genotypes of CMB9A and CMB9B family had the best segregation. A total of 486 microsatellite primers were evaluated using bulked segregant analysis (BSA), 11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals. In conclusion, fecundity was the parameter that impacted most on the intrinsic rate of A. socialis population growth. 相似文献
30.
González-de-la-Vara Mdel R Valdez RA Lemus-Ramirez V Vázquez-Chagoyán JC Villa-Godoy A Romano MC 《Canadian journal of veterinary research》2011,75(3):216-221
Dairy cattle suffer stress from management and production; contemporary farming tries to improve animal welfare and reduce stress. Therefore, the assessment of long-term hypothalamic-pituitary-adrenal function using non-invasive techniques is useful. The aims in this study were: to measure cortisol concentration in cow and calves hair by radioimmunoassay (RIA), to test cortisol accumulation in bovine hair after adrenocorticotropic hormone (ACTH) challenges, and determine the influence of hair color on cortisol concentrations. Fifteen Holstein heifers were allotted to 3 groups (n = 5 each): in control group (C), just the hair was sampled; in the saline solution group (SS), IV saline solution was administered on days 0, 7, and 14; and the ACTH group was challenged 3 times with ACTH (0.15 UI per kg of body weight) on days 0, 7, and 14. Serum samples from the SS and ACTH groups were obtained 0, 60 and 90 min post-injection. Serum cortisol concentration was greater 60 and 90 min after injection with ACTH. Hair was clipped on days 0, 14, 28, and 44. Hair cortisol was methanol extracted and measured by RIA. Hair cortisol was preserved for 11 mo. Hair cortisol concentrations in the ACTH group were greater than in the saline and control groups on days 14 and 28, but not on day 44. Concentrations were greater in calves than in cows and greater in white hair than in black hair. Cortisol accumulated in bovine hair after ACTH challenges, but the concentration was affected by both age and hair color. If hair color effects are taken into account, assessing cortisol concentration in hair is a potentially useful non-invasive method for assessing stress in cattle. 相似文献