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991.
Ramos Silvio Junio Caldeira Cecílio Frois Gastauer Markus Costa Deborah Luciany Pires Furtini Neto Antonio Eduardo de Souza Filipe Bittencourt Machado Souza-Filho Pedro Walfir Martins Siqueira Jose Oswaldo 《New Forests》2019,50(5):859-872
New Forests - For the effective use of native plants for mineland revegetation, an understanding of seed dormancy break and germination requirements, and seed storage tolerance is indispensable. In... 相似文献
992.
Luis O. Solis-Sánchez Rodrigo Castañeda-Miranda Juan J. García-EscalanteIrineo Torres-Pacheco Ramón G. Guevara-GonzálezCelina L. Castañeda-Miranda Pedro D. Alaniz-Lumbreras 《Computers and Electronics in Agriculture》2011,75(1):92-99
One of the main problems in greenhouse crop production is the presence of pests. In order to address this problem, the implementation of a Integrated Pest Management (IPM) system involving the detection and classification of insects (pests) is essential for intensive production systems. Traditionally, this has been done by placing hunting traps in fields or greenhouses and later manually counting and identifying the insects found. This is a very time-consuming and expensive process. To facilitate this process, it is possible to use machine vision techniques. This work describes an application of the machine vision system LOSS V2 algorithm, an expanded version of the LOSS algorithm discussed in a previous work by the same authors. This expanded version demonstrated improved potential and was used to detect and identify the following pest species: Diabrotica (Coleoptera: Chrysomelidae), Lacewings (Lacewings spp.), Aphids (Aphis gossypii Genn.), Glassy (Empoasca spp.), Thrips (Thrips tabaci L.), and Whitefly (Bemisia tabaci Genn.). The algorithm identifies pest presence in the crop and makes it possible for the greenhouse manager to take the appropriate preventive or corrective measures. The LOSS V2 involves the application of the LOSS algorithm for initial pest identification, followed by the application of the image processing technique known as scale invariant feature transform (SIFT). This allows for more accurate pest detection because it is possible to discriminate and identify different types of insects. Therefore, when compared to manual pest counting, the newly developed LOSS V2 algorithm showed more precision in identifying different pest varieties, and also, a much higher determination coefficient, R2 = 0.99. 相似文献
993.
Uriel Ramírez-Rivera José Roberto Sanginés-García José Guadalupe Escobedo-Mex Fanny Cen-Chuc Juan Antonio Rivera-Lorca Pedro Enrique Lara-Lara 《Agroforestry Systems》2010,80(2):295-302
Feed intake and digestibility were evaluated in sheep fed low quality Taiwan grass supplemented with Tithonia diversifolia. Four wether hair sheep were housed in metabolic cages and fed with either Control concentrate 20%, Tithonia 20, 35 or 50%
in a Latin Square design. Adaptation and, feces and urine collection periods were 14 and 7 days, respectively. Feed intake
was increased (P < 0.01) from 58.5 in control to 86.1 g/kg0.75 in sheep fed Tithonia. NDF intake and digestibility were affected by Tithonia level. Nitrogen intake increased linearly (P < 0.01) with increase in feces and urine excretion. N retention was similar (P > 0.1) among sheep fed Tithonia, but different (P < 0.05) from control. Inclusion of Tithonia foliage at 20% of the DM diet of hair sheep improved their intake of low quality
Taiwan grass and nitrogen retention. Higher levels of Tithonia in the diet, however, increase nitrogen loss in feces and urine. 相似文献
994.
Bárbara Cuesta Pedro Villar-Salvador Jaime Puértolas Douglass F. Jacobs José M. Rey Benayas 《Forest Ecology and Management》2010
We analysed the physiological bases that explain why large and high nitrogen (N) concentration seedlings frequently have improved survival and growth relative to small seedlings in Mediterranean woodland plantations. Large seedlings of Aleppo pine (Pinus halepensis Mill.) and holm oak (Quercus ilex L.) with high N concentration (L+), and small seedlings with either high (S+) or low (S−) N concentration, were planted on two sites of different weed competition intensity that created contrasting stress conditions. Seedling survival, growth, gas exchange, N remobilization (NR) and uptake (NU), and water potential were assessed through the first growing season. Weeds reduced survival and growth, but seedling response to weed competition varied among phenotypes and between species. At the end of the first growing season, L+ Aleppo pine seedlings had higher survival than both small seedling types in presence of weeds but no differences were observed in absence of weeds. Mortality differences among phenotypes occurred in spring but not in summer. L+ Aleppo pines grew more than small Aleppo pines independently of weed competition. No holm oak seedling type survived in presence of weeds and no mortality differences among phenotypes where observed in absence of weeds, although L+ holm oak seedlings grew more than small seedlings. Mortality and growth differences in Aleppo pine were linked to marked physiological differences among phenotypes while physiological differences were small among holm oak phenotypes. L+ Aleppo pines had greater root growth, gas exchange, NR, and NU than small seedlings, irrespective of their N concentration. Seedling size in Aleppo pine had a greater role in the performance of transplanted seedlings than N concentration. The functional differences among oak phenotypes were small whereas they were large in pine seedlings, which led to smaller differences in transplanting performance in holm oak than in pine. This suggests that the nursery seedling quality improvement for planting in dry sites could depend on the species-specific phenotypic plasticity and functional strategy. Improved transplanting performance in large Aleppo pine seedlings relative to small seedlings was linked to greater gas exchange, root growth and N cycling. 相似文献
995.
Activity-guided fractionation of the methanol extract of Ebenus pinnata aerial parts led to the isolation of ombuoside (1), kaempferol 3-O-rutinoside (2), rutin (3), catechin (4), and picein (5), along with beta-sitosterol and beta-sitosterol glucoside. Compounds 1-4 showed significant antioxidant activity in the DPPH, and TEAC, reducing power assays. 相似文献
996.
Lezama-Dávila CM Isaac-Márquez AP Zamora-Crescencio P Uc-Encalada Mdel R Justiniano-Apolinar SY del Angel-Robles L Satoskar A Hernández-Rivero L 《Fitoterapia》2007,78(3):255-257
Extracts of the root of Pentalinon andrieuxii, vernacular name of "contrahierva" (solen ak' in Mayan language, were investigated for their lethal effect on the protozoa Leishmania mexicana. The hexanes extract was highly effective to delay and eventually stop parasite survival. 相似文献
997.
Khalid Majourhat Youssef Jabbar Abdellatif Hafidi Pedro Martínez-Gómez 《Annals of Forest Science》2008,65(8):805-805
998.
David Fernández-Calviño Pedro Soler-Rovira Montserrat Díaz-Raviña César Plaza 《Soil biology & biochemistry》2010,42(12):2119-2127
Copper-based fungicides have been applied in vineyard soils for a long time, which has resulted in increasing soil Cu concentration. However, information relating to non-target effects of these fungicides on microorganisms of these soils is scarce. The aim of this study was to determine the potential enzyme activities of vineyard soils in relation to Cu content and evaluate the potential risks of long-term application of Cu-based fungicides. For this purpose, a wide range of soil samples, having different total, exchangeable and bioavailable Cu contents, were collected from six regions of quality wines located in the NW Iberian Peninsula, and the activity of dehydrogenase, β-glucosidase, urease and phosphatase were measured. Overall, the results obtained indicate adverse effects of Cu on dehydrogenase, β-glucosidase and phosphatase activities and an inconsistent effect on urease activity. Threshold Cu concentrations at which changes in the enzyme activities became evident were 150-200 mg total Cu kg−1 and 60-80 mg bioavailable Cu kg−1. 相似文献
999.
Jesús Cerezo Valverde Silvia Martínez-Llorens Ana Tomás Vidal Miguel Jover Carmen Rodríguez Juán Estefanell Joan I. Gairín Pedro Miguel Domingues Carlos J. Rodríguez Benjamín García García 《Aquaculture International》2013,21(2):413-433
The amino acid composition and protein levels of three species of cephalopods (Octopus vulgaris, Loligo gahi and Todarodes sagittatus), the natural diets of common octopus (O. vulgaris) and different kinds of meals were determined in order to optimise the content of these nutrients in artificial feeds. Arginine, leucine and lysine were the most abundant essential amino acids in cephalopods, while glutamate and aspartate represented the main non-essential amino acids. Arginine and leucine were the limiting amino acid in most samples, with maximum Chemical Score values for mussel (79–98 %), squid (84 %) and crustaceans (65–91 %); medium for fish (41–70 %); and minimum for meals (29–64 %). Mussel, squid, crustaceans and fish showed a high essential amino acid index according to Oser (OI: 88–99 %) suggesting a suitable amino acid balance. The protein from animal meals (fish and krill) covered all the essential amino acids except arginine and lysine in fish meal. The vegetable meal presented the worst amino acid balance (OI: 74–89 %) with several deficiencies in essential amino acids, including arginine, threonine, lysine and methionine. Supplementation with arginine or leucine and protein complementation of crustaceans and bivalves with fish or animal meal are proposed as alternatives for improving the performance of protein in feed for cephalopods. 相似文献
1000.
Conrado Carrascosa Pedro Saavedra Rafael Millán José Raduán Jaber Tania Montenegro António Raposo 《Journal Of Aquatic Food Product Technology》2013,22(3):307-322
ABSTRACTThis study analyzes microbiological changes in whole, ungutted farmed gilthead sea bream (Sparus aurata) stored for an 18-day period in ice using traditional methods for mesophilic aerobic bacteria, psychrotrophic, Pseudomonas spp., Aeromonas spp., Shewanella putrefaciens, Enterobacteriaceae, sulphide-reducing Clostridium (Clostridia), and Photobacterium phosphoreum in muscle, skin, and gills, evaluating their seasonal differentiation. Two different statistical models were used to analyze microbiological growth. Simultaneously, physicochemical parameters such as the temperature, pH, biological oxygen demand (BOD), total dissolved solids, salinity, ammonia nitrogen, and total phosphorus content of growing waters were analyzed. The results showed that by the end of the storage time, specific spoilage bacteria (SSB) such as Pseudomonas spp., Aeromonas spp., and S. putrefaciens as H2S-producing bacteria were dominant in sea bream harvested in temperate water in the Canary Islands. Muscle tissue had the least contamination, followed by skin and gills. The values of the analyzed seawater parameters were constant during the four seasons, except that the temperature showed a small difference between winter and summer. Seasonal effects were observed among the fish analyzed, suggesting that the lower levels of contamination detected in winter may have been due to the slight difference observed in water temperature in that season. 相似文献