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171.
Wilson Geobel Ceiro-Catasú Ana Leonor Puertas Áreas Jersys Arévalo-Ortega Leopoldo Hidalgo Héctor Acosta-Salmón Edgar Omar Rueda-Puente 《国际虫害防治杂志》2018,64(4):359-364
The aim of this study was to determine the effectiveness of Pochonia chlamydosporia var. catenulata and the bacteria Tsukamurella paurometabola strain C-924 (HeberNem?), to control Meloidogyne incognita infection in a crop rotation system (cucumber, tomato and pepper) under greenhouse production during six crop cycles. We determined gall index, prevalence, intensity of disease, and number of juvenile nematodes in soil. At the end of the sixth cycle, plants protected with P. chlamydosporia showed a reduction in gall index (≤2), prevalence, and median (42%) intensity of disease similar or more pronounced than those observed in plants protected with T. paurometabola (80%). Both treatments were more efficient at reducing galling than at reducing prevalence and therefore reduction of intensity of disease was mainly due to the reduction in galling. The hydrolytic activity of P. chlamydosporia and its resistant spores make this fungus one of the best options for the long-term control of RKNs by decreasing egg masses or galls. Pochonia chlamydosporia var. catenulata is an important part of a potential biological control strategy in rotation systems of vegetable crop and can be used for long-time IPM strategies in Cuba and the Caribbean. 相似文献
172.
Neoechinorhynchus (Neoechinorhynchus) zabensis sp. n. (Acanthocephala: Neoechinorhynchidae) is described from Capoeta damascina (Valenciennes, 1842) (type host) and Capoeta trutta (Heckel, 1843) in the Greater and Lesser Zab Rivers, northern Iraq. The new species is unique among all other species of the genus by its characteristic paired para-vaginal muscular appendage and fragmented giant nuclei in the lemnisci. Eleven of the other 88 valid species of Neoechinorhynchus and N. zabensis have middle and posterior hooks of equal length. However, N. zabensis is distinguished from the others by size of trunk, proboscis, proboscis hooks and lemnisci, number of giant nuclei, position of female gonopore, and geographical and host distribution. It is also distinguished from six other species of Neoechinorhynchus previously reported from Iraq. Other distinguishing features are also included. 相似文献
173.
Ability of plant-based surface technology to improve urban water cycle and mesoclimate 总被引:1,自引:0,他引:1
Felipe Omar Tapia Silva Anne Wehrmann Hans-Joachim Henze Nikolaus Model 《Urban Forestry & Urban Greening》2006,4(3-4):145-158
The presented study proposes a technology that could be used in developing a stormwater management strategy. The research was conducted under the hypothesis that a plant-based surface system (PBSS) can increase the capacity of sealed urban surfaces, for example, along railway tracks, to reduce runoff volume, to increase evaporation and consequently to improve the mesoclimate. To test this statement, water retention capacity, runoff–precipitation ratio, runoff delay and evapotranspiration performance were determined for different time periods (rainwater events, daily, monthly, seasonally, yearly, and throughout the entire measuring period of 18 months) by means of a measurement strategy implemented in selected urban traffic areas of Berlin, Germany, that contained railway tracks. Additionally, a computation of the air humidity improvement of an urban test location based in measurements is presented. The main elements of the tested PBSS were a 2 cm thick vegetation mat and a 20 cm thick drainage layer. The measurement strategy for the hydrological characterization included the installation and use of weighable lysimeters, rain gauges and runoff volume counters. The runoff volume determined in some summer months for the PBSS technology amounted to 9% of precipitation. The evaporation performance in these months amounted to 100% of precipitation. These results were compared with the corresponding calculated values for an asphalt surface: runoff 70–80% of precipitation and evaporation performance of 20–30% of precipitation. The study provides evidence of the positive effect of this technology on the local water balance of the treated sealed areas. 相似文献
174.
Many seasonally flooded habitats in the tropics are dominated by one or a few tree species. We tested the hypothesis that the inability to tolerate flooding restricts most species from becoming established in flood-prone habitats. We compared morphological and physiological responses to flooding in seedlings of Prioria copaifera Griseb., a species that forms monodominant stands in seasonally flooded habitats, and in three species confined to flood-free sites; namely, Calophyllum longifolium Willd., Virola surinamensis Aubl. and Gustavia superba (H.B.K.) Berg. Flooding reduced photosynthesis at Day 45 in all species by 10-30%. By Day 90, photosynthesis returned to the control rate in Prioria, but not in the other species. Flooding reduced stomatal conductance by 25-35% in all species except Calophyllum, and it reduced leaf area growth by 44% in Virola, but not in the other species. All species survived 90 days of flooding without mortality, leaf chlorosis, leaf necrosis, or leaf abscission. Flooding reduced root:shoot ratio significantly in Gustavia and Calophyllum, but not in the other species, and it reduced maximum root depth by 29% in Prioria, but by 61% or more in the species from flood-free habitats. 相似文献
175.
A new kaurenoid, ent-3β,7α,14β-trihydroxykaur-16-ene-12,15-dione (1), named pseurata G, was isolated from the ethanol extract of the whole plant of Rabdosia pseudo-irrorata. 相似文献
176.
Macedo RJ Arredondo V García F Aguilar M Prado O Rodríguez R 《Tropical animal health and production》2012,44(2):349-354
The effects of supplemental yeast culture, litter size, stage and number of lactation on milk composition were studied in
Pelibuey ewes. Twenty ewes were randomly assigned to one of two dietary treatments. Ten control ewes grazed on guinea grass
(Panicum maximum) and were supplemented with concentrate. A further ten ewes received the same diet with 14 g/head/day of yeast culture (Saccharomyces cerevisiae). Colostrum was collected within 24 h after parturition, and subsequently, milk samples were collected at fortnightly intervals
(7, 21, 35, and 49 days). Total solids content averaged 32% in colostrum and 12.5% in milk. Colostrum of primiparous ewes
had higher total solids content than that of ewes with more than five lactations. However, ewes with more than five lactations
produced milk with higher net energy, total solids, protein, and casein than ewes with fewer lactations. Milk at 7 days had
a significantly higher content of energy, total solids, and fat than milk at 21, 35, and 49 days. Total solids content was
lower for ewes rearing one lamb than larger litter sizes. Supplementation with yeast culture did not affect the composition
of colostrum and milk, which was mainly affected by the stage and number of lactation. 相似文献
177.
Omar F. El‐Gayar 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):109-128
Abstract The recent advances in information technology (IT) have had profound impacts on all walks of life and aquaculture is no exception. The growing importance of aquaculture as an alternative source of protein has further emphasized the need to adapt and develop advanced IT for the better management of aquaculture facilities as well as the regional planning for aquaculture development. It is the objective of this paper to review the use and potential prospects of IT in aquaculture management. The information technologies considered are instrumentation and process control, data management, computerized models, decision support systems, artificial intelligence and expert systems, image processing and pattern recognition, geographical information systems, and information centres and networks. The review includes a brief introduction of each of the aforementioned technologies, followed by a survey of their current application as well as their potential use in aquaculture management. 相似文献
178.
The worlds’ current food production system is focused on a limited number of crops. However, international food demand is
increasingly looking for more diversified supplies. In the Venezuelan State Amazonas, the Piaroa indigenous people collect
and cultivate several indigenous species with local, regional, national and even international potential. A participatory
approach was used to select, in cooperation with these Piaroa people, a list of products for in-depth economic analysis and
for introduction in agroforestry trials in a later phase. Seven agroforestry food products of this list were identified as
underutilized. Primary data collected through consumer and trader surveys on the local markets and participatory exercises
in selected Piaroa communities revealed that the main causes of underutilization are the general lack of transport, processing
and market infrastructure in Amazonas; the lack of demand, due to a lack of product information; the lack of market information
and cooperation between the different market chain actors; and the low productivity of the traditional slash and burn plots.
Solutions to overcome the infrastructural constraints are sought by looking at the example set by a local NGO.
相似文献
Tinne Van LooyEmail: |
179.
Rukunga GM Muregi FW Tolo FM Omar SA Mwitari P Muthaura CN Omlin F Lwande W Hassanali A Githure J Iraqi FW Mungai GM Kraus W Kofi-Tsekpo WM 《Fitoterapia》2007,78(7-8):455-459
In the present study the methanolic extract of Albizia gummifera was fractionated into various fractions. These fractions were tested against choroquine sensitive (NF54) and resistant (ENT30) strains of Plasmodium falciparum. All other fractions apart from the alkaloidal fraction showed low activity with IC 50 above 3 microg/ml. The alkaloidal fraction exhibited strong activity against NF54 and ENT30 with IC 50 of 0.16+/-0.05 and 0.99+/-0.06 microg/ml, respectively. Five known spermine alkaloids were isolated from the alkaloidal fraction. These alkaloids exhibited activities against NF54 and ENT30 with IC 50 ranging from 0.09+/-0.02 to 0.91+/-0.10 microg/ml. Four of the alkaloids were further evaluated for in vivo activity against rodent malaria parasite Plasmodium berghei. The alkaloids showed percentage chemosuppression of parasitaemia in mice ranging from 43 to 72%. The use of the extracts A. gummifera for treatment of malaria in traditional medicine seems to have a scientific basis. 相似文献
180.
Dayna Filocreão Malheiros Icaro Rodrigues Sarquis Irlon Maciel Ferreira Patrick Delgado Mathews Omar Mertins Marcos Tavares-Dias 《Journal of fish diseases》2020,43(6):687-695
This study compared the in vitro anthelmintic activity of Copaifera reticulata oleoresin (200, 400, 600, 800 and 1,000 mg/L) and of nanoemulsions prepared with this oleoresin (50, 100, 150, 200 and 250 mg/L) against monogeneans on the gills of Colossoma macropomum. The major compounds present in the oleoresin of C. reticulata were γ-macrocarpene (14.2%), α-bergamotene (13.6%), β-selinene (13.4%) and β-caryophyllene (11.7%). All concentrations of the nanoemulsion and the oleoresin without nanoformulation showed anthelmintic efficacy against monogeneans, and higher concentrations led to more rapid parasite mortality. Structural damages to the tegument of the parasites exposed to C. reticulata oleoresin were observed with scanning electron microscopy. At two hours of exposure, fish showed 100% tolerance to all nanoemulsion concentrations used in the in vitro assays, whereas 100% mortality was shown in the fish exposed to the oleoresin without nanoformulation after one hour. The results of this study suggest that nanoemulsions with oleoresin of C. reticulata have advantages in the control and treatment of monogenean infections in C. macropomum when compared to the oleoresin without nanoformulation. In addition, since nanoemulsions with the C. reticulata oleoresin are safe to control monogeneans, the efficacy of these nanoformulations may be assayed in therapeutic baths to treat C. macropomum infected by monogeneans. 相似文献