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991.
Forest Law Enforcement, Governance, and Trade agreements between the EU and countries that grow tropical timber aim to complement, alter, or generate new regulatory mechanisms that ensure the legality of timber products. These regulatory changes affect pre-existing policies and practices within timber production networks. The Indonesian-EU Voluntary Partnership Agreement was signed in 2013, and legality verification is scheduled to become mandatory for all smallholders by the end of 2017. Using grower surveys conducted in the Jepara regency of Central Java (n = 204), we generate information on who Jepara smallholders are, what timber species they are growing, and how programs that provide free and discounted seedlings contribute to STP. We use these data to understand how STP operates and how Sistem Verifikasi Legalitas Kayu (SVLK), the Indonesian method for timber legality verification, will affect STP networks and producers. We find that resource provision and oversight of source documentation increase formalization within STP. Our discussion details four policy-relevant insights for promoting STP amid continued formalization.  相似文献   
992.
Copper is an active component of some commercial algaecides and is commonly found in low concentrations in contaminated aquatic systems. Unintended consequences of algaecide application include macrophyte bioaccumulation and possible trophic level bioamplification especially by specialist herbivores. Trophic level effects of copper contamination were observed through feeding trials using the mustard beetle (Phaedon viridis). Several metals, including copper, interfere with the myrosinase enzyme system responsible for the watercress (Nasturtium officinale) allelopathic defense against herbivory. The mustard beetle is a specialist herbivore that has evolved a detection system that is stimulated by the products of the glucosinolate-myrosinase system. Because copper interferes with myrosinase enzymes, mustard beetles were expected to avoid copper-contaminated plants. While larvae exhibited a slight preference for contaminated plants, adult mustard beetles in this experiment exhibited a statistically significant preference for plants uncontaminated with copper.  相似文献   
993.
Forty-four Asparagus officinalis cultivars, gene bank accessions and breeding lines as well as thirty-four accessions of wild relatives of Asparagus were evaluated for resistance to Asparagus virus 1. Three different test strategies were developed for the assessment of individual plants: (1) natural infection under field conditions, or two vector-mediated infection assays using the green peach aphid Myzus persicae (2) in an insect-proof gauze cage or (3) in a climate chamber. The AV-1 infections were verified by DAS-ELISA and RT-PCR approaches. All tested 660 individual plants of A. officinalis germplasm were susceptible to AV-1 infection. In contrast, in 276 plants of 29 Asparagus wild accessions no virus infection could be detected. These resistant accessions comprised of nineteen diploid, tetraploid and hexaploid species of both the Eurasian clade and the African clade of the asparagus germplasm. Data of the AV-1 resistance evaluation are discussed in relation to the genetic distance of the resistance carrier and potential application in breeding.  相似文献   
994.
A study was conducted on 37 randomly selected broiler poultry farmers in Rwanda to characterize the production system using pre-tested semi-structured questionnaires. The data were processed in SPSS and presented as means, percentages and ranges in tables and text. All respondents kept Cobb breed and young stock was mainly (73 %) imported from abroad. The majority of respondents were males (68 %) and most farmers had attended only primary level of education (40.5 %). Most of the farms were in the peri-urban (48.6 %) and urban (37.8 %) areas and hired male youth (62.2 %) mainly aged 19–35 years. The majority of respondents (68 %) kept less than 500 birds per batch. Recordkeeping was well practiced (91.9 %) and (62.6 %) had permanent poultry houses and all farmers used deep litter system. Purchased feedstuffs were reportedly (92 %) mixed at farm level as the main feed resource. Maize bran was reported (97.06 %) the main, basal feedstuff. The mortality rates of chick and growers were 12.3 and 9.4 %, respectively. The slaughter age was reportedly 60 days with an average dressing percentage of 75.67 %. The main challenges reported were scarcity and unaffordability of quality feeds (59.5 %), lack of market access (45 %) and lack of credit (21 %). The farmers had various views on improving broiler production in Rwanda ranging from establishing feed processing industries 62.2 %, improving marketing facilities 35.1 %, increasing availability of day-old chick and access credit 27 %, to intensification of farmer training 16.2 %.  相似文献   
995.
On a global research expedition, over 500 bacterial strains inhibitory towards pathogenic bacteria were isolated. Three hundred of the antibacterial strains were assigned to the Vibrionaceae family. The purpose of the present study was to investigate the phylogeny and bioactivity of five Vibrionaceae strains with pronounced antibacterial activity. These were identified as Vibrio coralliilyticus (two strains), V. neptunius (two strains), and Photobacterium halotolerans (one strain) on the basis of housekeeping gene sequences. The two related V. coralliilyticus and V. neptunius strains were isolated from distant oceanic regions. Chemotyping by LC-UV/MS underlined genetic relationships by showing highly similar metabolite profiles for each of the two V. coralliilyticus and V. neptunius strains, respectively, but a unique profile for P. halotolerans. Bioassay-guided fractionation identified two known antibiotics as being responsible for the antibacterial activity; andrimid (from V. coralliilyticus) and holomycin (from P. halotolerans). Despite the isolation of already known antibiotics, our findings show that marine Vibrionaceae are a resource of antibacterial compounds and may have potential for future natural product discovery.  相似文献   
996.
In this study dealing with the development of management strategies for P. ramorum in Rhododendron stands several plant protection and fertilizer products were tested for their suitability to control this pathogen on Rhododendron. Tests were conducted on young potted plants and abscised leaves, using the following products: phosphite (Nutri-Phite® PK), copper hydroxide (Cuprozin® liquid), Bacillus subtilis (Serenade®), a mycorrhizal preparation, and a product based on ‘effective microorganisms’ (EMa). Although transmission of the pathogen from infected to healthy plants was successfully inhibited by phosphite, Cu hydroxide and B. subtilis, subsequent tests showed that only phosphite and Cu hydroxide had a significant effect on disease development. All other preparations based on antagonistic or growth promoting microorganisms had no preventive or curative effect. While B. subtilis tended to increase disease symptoms, the remaining products caused a slight reduction of disease severity only. In contrast, phosphite and Cu hydroxide almost completely inhibited infection by P. ramorum. Therefore, in field situations, the use of the ecologically safe, systemic phosphite against P. ramorum in Rhododendron stands appears to be reasonable and advisable. Along with other supporting measures within the framework of a management strategy, this will allow to prevent or slow down further spread of the disease.  相似文献   
997.
Twenty four isolates of Fusarium graminearum, half of which were 3-acetyldeoxynivalenol (3-ADON) and half 15-acetyldeoxynivalenol (15-ADON) chemotypes, were tested for their ability to produce deoxynivalenol and to cause Fusarium head blight (FHB) in spring wheat cultivars. The objectives of this study were to determine (1) whether 3-ADON isolates differ in aggressiveness, as measured by the FHB index, and DON production from 15-ADON isolates under field conditions, and (2) whether the performance of resistant host cultivars was stable across isolates. Field tests of all isolates were conducted with three replicates at each of two locations in Canada and Germany in 2008 with three host genotypes differing in FHB resistance level. The resistant host genotype showed resistance regardless of the chemotype or location. The differences between mean FHB indices of 3-ADON and 15-ADON isolates were not significant for any wheat genotype. In contrast, average DON production by the 3-ADON isolates (10.44 mg kg−1) was significantly (P < 0.05) higher than for the 15-ADON isolates (6.95 mg kg−1) at three of the four locations where moderately resistant lines were tested, and at both locations where susceptible lines were evaluated. These results indicate that 3-ADON isolates could pose a greater risk to food safety. However, as the mean aggressiveness and DON production of 3-ADON and 15-ADON chemotypes was similar on highly resistant lines, breeding and use of highly resistant lines is still the most effective measure of reducing the risks associated with DON in wheat.  相似文献   
998.
The response of maize (Zea mays) to banded variable-rate nitrogen (N) application over a period of 3 years (2002/3–2004/5) is analyzed. The experimental design alternated variable-rate (VR) and single-rate (SR) applications of N. The yield monitor data were spatially autocorrelated and therefore were analyzed with spatial regression methods. The baseline spatial regression model defined in this study showed that the VR treatment, treatment by year and treatment by management zone were statistically significant. Sensitivity tests were applied; the first showed that VR treatment had a yield advantage when soil depth was greater than the field average of 174 cm. The second test showed that the VR N rates applied were close to those that would maximize profit. Partial budgeting indicates that benefits from VR vary from year to year, but in this test VR was slightly more profitable than uniform rate application. Economic sensitivity testing indicates that farm size and the price of maize are the key factors in the profitability of VR N.  相似文献   
999.
Daily consumption of fruits and vegetables is frequently recommended to prevent several diseases. This health-promoting effect is considered to be in part due to the antioxidant content of fruits and vegetables and their ability to decrease oxidative stress. To investigate whether the ingestion of preparations from spinach or perilla, two carotenoid-rich leafy vegetables, is followed by an increase in carotenoid concentration and/or affects parameters of oxidative stress in human blood plasma. 12 healthy volunteers ingested a perilla- or spinach preparation for 10 days (5 mg lutein/d). We quantified antioxidant levels in plasma, kinetics of lipid peroxidation, MDA concentration, and total antioxidative capacity of plasma. We observed a significant increase in lutein content and a moderate increase (n.s.) in β-carotene content in human blood plasma after consumption of spinach or perilla. The markers of lipid peroxidation tended to decrease, but no influence on antioxidative capacity of plasma could be detected. The high lutein content of perilla caused a more pronounced increase of lutein compared to spinach. Both vegetables seem to be able to influence lipid peroxidation in a beneficial manner.  相似文献   
1000.
Fungal disease suppression by inorganic salts: A review   总被引:1,自引:0,他引:1  
This paper reviews the scientific literature on the topic of fungal disease suppression by applications of inorganic salts as alternatives to synthetic fungicides on a global scale for both protected and field crops. Where data were available, the comparative efficacy of inorganic salts with conventional fungicide products is discussed. In total, published evidence was found for 34 inorganic salts (mainly bicarbonates, phosphates, silicates, chlorides and phosphites) that were able to reduce the severity of 49 fungal diseases (of the foliage, stem, fruit, tuber, root and post-harvest) in 35 plant species (vegetables, cereals, fruit crops, root/tuber crops, ornamentals and native plants). The most studied and best controlled disease with inorganic salts was powdery mildew of cucurbits [Sphaerotheca fuliginea (Schltdl.) Pollacci 1913 or Erysiphe cichoracearum DC. 1805; up to 99% efficacy], wheat [Blumeria graminis (DC.) Speer 1975 (f. sp. tritici)] and grapes [Uncinula necator (Schwein.) Burrill 1892]. The next best evidence for disease control was for wheat septoria blotch (Septoria tritici Berk. & M.A. Curtis 1874), rice blast [Magnaporthe grisea (T.T. Hebert) M.E. Barr 1977], potato late blight [Phytophthora infestans (Mont.) de Bary 1876] and several other Phytophthora spp. The published evidence suggests that these 34 inorganic salts are generally less effective than conventional fungicides and could not fully replace them. However, their integration in a disease management strategy may enable a reduction in the number of conventional fungicide applications required. The potential for the inclusion of inorganic salts in fungal disease management programmes merits further investigation and greater regulatory innovation in the near future.  相似文献   
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