ABSTRACT
Raising attentions have focused on how to alleviate greenhouse gas (GHG) emissions from orchard system while simultaneously increase fruit production. Microalgae-based biofertilizer represents a promising resource for improving soil fertility and higher productivity. However, the effects of microalgae application more especially live microalgae on GHG emissions are understudied. In this study, fruit yield and quality, GHG emissions, as well as soil organic carbon and nitrogen fractions were examined in a hawthorn orchard, under the effects of live microalgae-based biofertilizer applied at three doses and two modes. Compared with conventional fertilization, microalgae improved hawthorn yield by 15.7%-29.6% with a maximal increment at medium dose by root application, and significantly increased soluble and reducing sugars contents at high dose. While microalgae did not increase GHG emissions except for nitrous oxide at high dose by root application, instead it significantly increased methane uptake by 1.5-2.3 times in root application. In addition, microalgae showed an increasing trend in soil organic carbon content, and significantly increased the contents of soil dissolved organic carbon and microbial biomass carbon, as well as soil ammonium nitrogen and dissolved organic nitrogen at medium dose with root application. Overall, the results indicated that the live microalgae could be used as a green biofertilizer for improving fruit yield without increasing GHG emissions intensity and the comprehensive greenhouse effect, in particular at medium dose with root application. We presume that if lowering chemical fertilizer rates, application of the live microalgae-based biofertilizer may help to reduce nitrous oxide emissions without compromising fruit yield and quality.
Subject(s)
Crataegus , Fertilizers , Fruit , Greenhouse Gases , Microalgae , Nitrogen , Soil , Fertilizers/analysis , Greenhouse Gases/analysis , Fruit/growth & development , Fruit/metabolism , Microalgae/growth & development , Microalgae/metabolism , Soil/chemistry , Nitrogen/analysis , Nitrogen/metabolism , Crataegus/growth & development , Carbon/analysis , Carbon/metabolism , Biomass , Methane/analysis , Methane/metabolism , Nitrous Oxide/analysis , Nitrous Oxide/metabolismABSTRACT
The effect of hawthorn berries ripeness on the physicochemical, structural and functional properties of hawthorn pectin (HP) and its potential in sweet cherry preservation were investigated. With the advanced ripeness of hawthorn berries, the galacturonic acid (GalA) content decreased from 59.70 mol% to 52.16 mol%, the molecular weight (Mw) reduced from 368.6 kDa to 284.3 kDa, the microstructure exhibited variable appearance from thick lamella towards porous cross-linked fragment, emulsifying activity and emulsions stability, antioxidant activities, α-amylase and pancreatic lipid inhibitory capacities significantly increased. The heated emulsion stored for 30 d presented higher creaming index and more ordered oil droplets compared to the unheated emulsion. With the extended berries ripeness, the firmness of HP gels remarkably decreased from 225.69 g to 73.39 g, while the springiness increased from 0.78 to 1.16, HP exhibited a superior inhibitory effect in water loss, browning, softening, and bacterial infection in sweet cherries preservation.
Subject(s)
Crataegus , Fruit , Pectins , Crataegus/chemistry , Crataegus/growth & development , Pectins/chemistry , Fruit/chemistry , Fruit/growth & development , Food Preservation , Antioxidants/chemistry , Molecular Weight , Emulsions/chemistry , alpha-Amylases/chemistry , alpha-Amylases/metabolism , Plant Extracts/chemistryABSTRACT
Crataegi folium have been used as medicinal and food materials worldwide due to its pharmacological activities. Although the leaves of Crataegus songorica (CS), Crataegus altaica (CA) and Crataegus kansuensis (CK) have rich resources in Xinjiang, China, they can not provide insights into edible and medicinal aspects. Few reports are available on the qualitative and quantitative analysis of flavonoids compounds of their leaves. Therefore, it is necessary to develop efficient methods to determine qualitative and quantitative flavonoids compounds in leaves of CS, CA and CK. In the study, 28 unique compounds were identified in CS versus CK by qualitative analysis. The validated quantitative method was employed to determine the content of eight flavonoids of the leaves of CS, CA and CK within 6 min. The total content of eight flavonoids was 7.8-15.1 mg/g, 0.1-9.1 mg/g and 4.8-10.7 mg/g in the leaves of CS, CA and CK respectively. Besides, the best harvesting periods of the three species were from 17th to 26th September for CS, from 30th September to 15th October for CA and CK. The validated and time-saving method was successfully implemented for the analysis of the content of eight flavonoids compounds in CS, CA and CK for the first time.
Subject(s)
Crataegus/chemistry , Flavonoids/analysis , China , Chromatography, High Pressure Liquid , Crataegus/classification , Crataegus/growth & development , Flavonoids/chemistry , Molecular Structure , Plant Leaves/chemistry , Plants, Edible/chemistry , Plants, Medicinal/chemistry , Seasons , Tandem Mass SpectrometryABSTRACT
AIM: Exploration of microbes isolated from rhizospheric soil of Crataegus oxycantha for bioactive natural products. METHODS AND RESULTS: A strain of Streptomyces sp. (C-7) was isolated from rhizospheric soil of C. oxycantha. The 16S rRNA gene sequence of strain C-7 displayed 99% sequence similarity with different Streptomyces species. The highest score was displayed for Streptomyces sp. strain Chy2-8 followed by Streptomyces violarus strain NBRC13104 and Streptomyces arenae strain ISP5293. The position of C-7 in the phylogenetic tree suggested uniqueness of the strain. Nalidixic acid (1), a quinolone antibiotic, was isolated from Streptomyces sp. strain (C-7) for the first time and characterized by NMR and chemically analysed. Compound 1 exhibited antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa. The production of compound 1 was also validated by repeating fermentation of strain C-7 and compound isolation in a separate natural product laboratory with no prior information. Furthermore, Compound 1 showed a cytotoxic effect against human prostate cancer cell line PC3 with an IC50 11 µg ml-1 . CONCLUSION: To the best of our knowledge, this is the first report showing production of nalidixic acid naturally by a strain of Streptomyces sp. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we isolated a strain of Streptomyces sp. producing nalidixic acid, which was otherwise only obtained through chemical synthesis.
Subject(s)
Anti-Bacterial Agents/biosynthesis , Crataegus/growth & development , Nalidixic Acid/metabolism , Soil Microbiology , Streptomyces/isolation & purification , Streptomyces/metabolism , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cell Line, Transformed , Cell Survival/drug effects , Escherichia coli/drug effects , Humans , Nalidixic Acid/chemistry , Nalidixic Acid/pharmacology , Phylogeny , Plant Extracts , Pseudomonas aeruginosa/drug effects , RNA, Ribosomal, 16S/genetics , Streptomyces/classification , Streptomyces/geneticsABSTRACT
The apple maggot fly, Rhagoletis pomonella Walsh (Diptera: Tephritidae), is a serious quarantine pest in the apple-growing regions of central Washington and Oregon. The fly is believed to have been introduced into the Pacific Northwest via the transport of larval-infested apples near Portland, Oregon, within the last 40 yr. However, R. pomonella also attacks native black hawthorn, Crataegus douglasii Lindley (Rosales: Rosaceae), and introduced ornamental hawthorn, Crataegus monogyna Jacquin, in the region. It is, therefore, possible that R. pomonella was not introduced but has always been present on black hawthorn. If true, then the fly may have independently shifted from hawthorn onto apple in the Pacific Northwest within the last 40 yr after apples were introduced. Here, we test the introduction hypothesis through a microsatellite genetic survey of 10 R. pomonella sites in Washington and 5 in the eastern United States, as well as a comparison to patterns of genetic variation between populations of Rhagoletis cingulata Loew and Rhagoletis indifferens Curran, two sister species of cherry-infesting flies known to be native to the eastern and western United States, respectively. We report results based on genetic distance networks, patterns of allelic variation, and estimated times of population divergence that are consistent with the introduction hypothesis for R. pomonella. The results have important implications for R. pomonella management, suggesting that black hawthorn-infesting flies near commercial apple-growing regions of central Washington may harbor sufficient variation to utilize apple as an alternate host, urging careful monitoring, and possible removal of hawthorn trees near orchards.
Subject(s)
Genetic Variation , Herbivory , Tephritidae/genetics , Animals , Crataegus/growth & development , DNA, Mitochondrial/genetics , Genotype , Introduced Species , Malus/growth & development , Microsatellite Repeats , Tephritidae/physiology , WashingtonABSTRACT
Few efforts have been made in Mexico to monitor Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) in commercial hawthorn (Crataegus spp.) crops. Therefore, the main objectives of this study were to evaluate infestation levels of R. pomonella in feral and commercial Mexican hawthorn and to assess the efficacy of different trap-lure combinations to monitor the pest. Wild hawthorn was more infested than commercially grown hawthorn at the sample site. No differences among four commercial baits (Biolure, ammonium carbonate, CeraTrap, and Captor + borax) were detected when used in combination with a yellow sticky gel (SG) adherent trap under field conditions. However, liquid lures elicited a slightly higher, although not statistically different, capture. Cage experiments in the laboratory revealed that flies tended to land more often on the upper and middle than lower-bottom part of polyethylene (PET) bottle traps with color circles. Among red, orange, green, and yellow circles attached to a bottle trap, only yellow circles improved fly captures compared with a colorless trap. A PET bottle trap with a red circle over a yellow background captured more flies than a similar trap with yellow circles. An SG adherent yellow panel trap baited with ammonium carbonate was superior to the improved PET bottle trap (red over a yellow background) baited with different liquid proteins, but a higher proportion of females and no differences in fly detection were measured in PET traps baited with protein lures. These trials open the door for future research into development of a conventional nonadherent trap to monitor or control R. pomonella.
Subject(s)
Carbonates/pharmacology , Insect Control/instrumentation , Pheromones/pharmacology , Phototaxis , Tephritidae/physiology , Animals , Color , Crataegus/growth & development , Female , Male , Mexico , Odorants/analysis , Tephritidae/drug effectsABSTRACT
BACKGROUND: Procyanidins from the bark of hawthorn (Crataegus monogyna Jacq.) were isolated and purified. Qualitative and quantitative composition was compared with that of the extract of hawthorn fruit (Crataegus monogyna Jacq.). Stability and antioxidant and anti-inflammatory properties of procyanidins before and after micro-encapsulation were estimated. The effects of the carrier type (inulin and maltodextrin) and procyanidins:carrier ratio (1:1, 1:3) and the influence of storage temperature (20 °C, -20 °C, -80 °C) on the content of procyanidins were evaluated. RESULTS: Samples before and after micro-encapsulation contained from 651 to 751 mg of procyanidins in 1 g. Among the procyanidins, (-)-epicatechin, dimer B2, and trimer C1 dominated. The use of inulin during spray drying resulted in greater efficiency of micro-encapsulation than the use of maltodextrin. During storage of the samples at 20 °C degradation of procyanidins was observed, whereas at -20 °C and -80 °C concentrations of them increased. CONCLUSION: The microcapsules with procyanidins from the bark of hawthorn, as well as the extract of procyanidins, have valuable biological activity, and strong antioxidant and anti-inflammatory properties. It is better to prepare microcapsules with a greater amount of carrier, with the procyanidin/carrier ratio 1:3. © 2016 Society of Chemical Industry.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Antioxidants/chemistry , Crataegus/chemistry , Inulin/chemistry , Polysaccharides/chemistry , Prebiotics/analysis , Proanthocyanidins/chemistry , Anti-Inflammatory Agents, Non-Steroidal/analysis , Antioxidants/analysis , Antioxidants/isolation & purification , Catechin/analogs & derivatives , Catechin/analysis , Catechin/chemistry , Chemical Phenomena , Cold Temperature , Crataegus/growth & development , Food Handling , Food Storage , Free Radical Scavengers/analysis , Free Radical Scavengers/chemistry , Free Radical Scavengers/isolation & purification , Fruit/chemistry , Fruit/growth & development , Inulin/analysis , Phenols/analysis , Phenols/chemistry , Plant Bark/chemistry , Plant Bark/growth & development , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Shoots/chemistry , Plant Shoots/growth & development , Polysaccharides/analysis , Proanthocyanidins/analysis , Proanthocyanidins/isolation & purificationABSTRACT
AIM: We evaluated the potential preventive and therapeutic effects of Crataegus aronia (C. aronia) in NAFLD induced by high-fat diet (HFD) in rat models. METHODS: Protective effect of Crataegus aronia or simvastatin was investigated in Wistar rats fed either low-fat diet (LFD) or HFD. RESULTS: Liver histopathological examinations confirmed the development of NAFLD in rats fed HFD. In both protective and therapeutic treatments, C. aronia significantly reduced liver index (3.85 ± 0.21% in HFD plus aronia group versus 6.22 ± 0.58% in HFD model group), increased the HDL-cholesterol and reduced the LDL-cholesterol in blood. The hawthorn plant also significantly ameliorated oxidative stress biomarker (p < 0.002) and liver enzymes (p < 0.0001) that indicate liver damage. CONCLUSION: C. aronia exhibits therapeutic and protective effects on NAFLD in an animal model possibly by its lipid lowering and antioxidant effects; thus, may offer therapeutic potential in humans.
Subject(s)
Anticholesteremic Agents/therapeutic use , Antioxidants/therapeutic use , Lipotropic Agents/therapeutic use , Liver/drug effects , Non-alcoholic Fatty Liver Disease/prevention & control , Oxidative Stress/drug effects , Plant Extracts/therapeutic use , Animals , Anticholesteremic Agents/adverse effects , Anticholesteremic Agents/isolation & purification , Antioxidants/adverse effects , Antioxidants/isolation & purification , Biomarkers/blood , Biomarkers/metabolism , Cholesterol, HDL/agonists , Cholesterol, HDL/blood , Cholesterol, LDL/antagonists & inhibitors , Cholesterol, LDL/blood , Crataegus/adverse effects , Crataegus/chemistry , Crataegus/growth & development , Diet, Fat-Restricted , Diet, High-Fat/adverse effects , Jordan , Lipotropic Agents/adverse effects , Lipotropic Agents/isolation & purification , Liver/metabolism , Liver/pathology , Liver/physiopathology , Male , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/pathology , Non-alcoholic Fatty Liver Disease/physiopathology , Plant Components, Aerial/chemistry , Plant Components, Aerial/growth & development , Plant Extracts/adverse effects , Plant Extracts/isolation & purification , Random Allocation , Rats, Wistar , Simvastatin/adverse effects , Simvastatin/therapeutic useABSTRACT
Hawthorn is a widely used herbal alternative medicine for the treatment of various cardiovascular diseases. However, the attributed health benefits, purported to be due to the presence of phenolic compounds, may depend on both the specific species and plant part. Studies to date investigating effects of hawthorn on heart disease(s) have used well-described European and/or Asian species, while little is known regarding the bioactivity of species native to North America. Six weeks of supplementation of both fireberry hawthorn berry (native Crataegus chrysocarpa) and English hawthorn leaf (C. monogyna, naturalized in North America) in the JCR:LA-cp rat, resulted in a significant reduction in heart weight, fasting LDL-C and improved heart function (p < 0.05). Fasting triglyceride and myocardial fibrosis were also reduced, but only by the berry extract. We demonstrate that both of the Canadian-sourced hawthorn extracts (introduced leaf and native berry) have cardioprotective benefits, likely via increased availability of nitric oxide.
Subject(s)
Cardiotonic Agents/therapeutic use , Crataegus/chemistry , Dietary Supplements , Dyslipidemias/prevention & control , Heart Diseases/prevention & control , Hypolipidemic Agents/therapeutic use , Plant Extracts/therapeutic use , Animals , Canada , Cholesterol, LDL/blood , Crataegus/growth & development , Dyslipidemias/blood , Dyslipidemias/pathology , Dyslipidemias/physiopathology , Fibrosis , Fruit/chemistry , Fruit/growth & development , Heart/physiopathology , Heart Diseases/blood , Heart Diseases/pathology , Heart Diseases/physiopathology , Introduced Species , Male , Myocardium/pathology , Organ Size , Plant Leaves/chemistry , Plant Leaves/growth & development , Random Allocation , Rats, Mutant StrainsABSTRACT
BACKGROUND: Canadian prairies are a habitat for unique wild plants. The main object of the present study was to investigate phytochemicals content and antioxidant activity in seven wild Canadian prairie fruits. METHODS: The presence of total phenolics, flavonoids, anthocyanins and antioxidant activity were identified in the extracts according to standard procedure. RESULTS: Wild rose had the highest amounts of total phenolics and total flavonoids, whereas elderberry exhibited the highest amount of anthocyanins. All extracts showed good scavenging activities towards DPPH radicals. The results showed a good linear relationship between oxygen radical absorbance capacity and total phenolics indicating that radicals are scavenged at a greater rate as the total phenolics content increases. Additionally, all extracts when applied at concentration of 800 ppm, showed ability to inhibit oxidation of canola oil. In SOT test the best results were obtained when extract of American mountain ash was used. In general, wild rose followed by American mountain ash demonstrated the highest antioxidant activity among assessed Canadian prairie fruits. CONCLUSIONS: From the results it can be concluded that prairie fruit extracts are a rich source of phenolic compounds and poses a high antioxidant activity, confirmed by assessment with different type of radicals employed.
Subject(s)
Antioxidants/isolation & purification , Elaeagnaceae/chemistry , Fruit/chemistry , Plant Extracts/isolation & purification , Rosaceae/chemistry , Sambucus/chemistry , Wilderness , Alberta , Anthocyanins/analysis , Antioxidants/chemistry , Crataegus/chemistry , Crataegus/growth & development , Dietary Fats, Unsaturated/analysis , Elaeagnaceae/growth & development , Fatty Acids, Monounsaturated/chemistry , Flavonoids/analysis , Food Preservatives/chemistry , Food Preservatives/isolation & purification , Food Storage , Fruit/growth & development , Hot Temperature , Phenols/analysis , Plant Extracts/chemistry , Prunus/chemistry , Prunus/growth & development , Rapeseed Oil , Rosa/chemistry , Rosa/growth & development , Rosaceae/growth & development , Sambucus/growth & development , Sorbus/chemistry , Sorbus/growth & developmentABSTRACT
Seasonal distributions of the western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), in sweet cherry (Prunus avium (L.) L.) (major host), black hawthorn (occasional developmental host) (Crataegus douglasii Lindley), and other trees were determined in a ponderosa pine ecosystem in Washington state, USA. The hypothesis that most fly dispersal from cherry trees occurs after fruit senesce or drop was tested, with emphasis on movement to black hawthorn trees. Sweet cherry fruit developed earlier than black hawthorn, bitter cherry (common host), choke cherry, and apple fruit. Flies were usually captured first in sweet cherry trees but were caught in bitter cherry and other trees throughout the season. Peak fly capture periods in sweet cherry began around the same time or slightly earlier than in other trees. However, peak fly capture periods in black hawthorn and other nonsweet cherry trees continued after peak periods in sweet cherry ended, or relative fly numbers within sweet cherry declined more quickly than those within other trees. Larvae were reared from sweet and bitter cherry but not black hawthorn fruit. Results provide partial support for the hypothesis in that although R. indifferens commonly disperses from sweet cherry trees with fruit, it could disperse more, or more flies are retained in nonsweet cherry trees after than before sweet cherries drop. This could allow opportunities for the flies to use other fruit for larval development. Although R. indifferens infestation in black hawthorn was not detected, early season fly dispersal to this and other trees and fly presence in bitter cherry could make fly management in sweet cherry difficult.
Subject(s)
Food Chain , Tephritidae/physiology , Animals , Crataegus/growth & development , Female , Larva/physiology , Male , Malus/growth & development , Population Dynamics , Prunus/growth & development , Seasons , Tephritidae/growth & development , WashingtonABSTRACT
Habitat fragmentation increases seed dispersal limitation across the landscape and may also affect subsequent demographic stages such as seedling establishment. Thus, the development of adequate plans for forest restoration requires an understanding of mechanisms by which fragmentation hampers seed delivery to deforested areas and knowledge of how fragmentation affects the relationship between seed-deposition patterns and seedling establishment. We evaluated the dispersal and recruitment of two bird-dispersed, fleshy-fruited tree species (Crataegus monogyna and Ilex aquifolium) in fragmented secondary forests of northern Spain. Forest fragmentation reduced the probability of seed deposition for both trees because of decreased availability of woody perches and fruit-rich neighborhoods for seed dispersers, rather than because of reductions in tree cover by itself. The effects of fragmentation went beyond effects on the dispersal stage in Crataegus because seedling establishment was proportional to the quantities of bird-dispersed seeds arriving at microsites. In contrast, postdispersal mortality in Ilex was so high that it obscured the seed-to-seedling transition. These results suggest that the effects of fragmentation are not necessarily consistent across stages of recruitment across species. Habitat management seeking to overcome barriers to forest recovery must include the preservation, and even the planting, of fleshy-fruited trees in the unforested matrix as a measure to encourage frugivorous birds to enter into open and degraded areas. An integrative management strategy should also explicitly consider seed-survival expectancies at microhabitats to preserve plant-population dynamics and community structure in fragmented landscapes.
Subject(s)
Conservation of Natural Resources/methods , Crataegus/growth & development , Demography , Ecosystem , Ilex/growth & development , Seeds/physiology , Trees , Animals , Birds/physiology , Crataegus/cytology , Ilex/cytology , Population Dynamics , Seeds/cytology , SpainABSTRACT
In our chemotaxonomic investigation of pharmaceutically relevant Crataegus species, the qualitative and quantitative flavonoid fingerprint of Crataegus monogyna and C. pentagyna is presented. Six flavonoids were identified as vitexin-2''-O-rhamnoside (1), vitexin (2), isovitexin (3), rutin (4), hyperoside (5), and isoquercitrin (6). Besides the verification of the main compounds isoorientin (7) and orientin (8) in C. pentagyna, further four flavonoids were isolated and identified as isoorientin-2''-O-rhamnoside (9), orientin-2''-O-rhamnoside (10), isovitexin-2''-O-rhamnoside (11), and 8-methoxykaempferol-3-O-glucoside (12) by means of 1D- and 2D-NMR, MS, and UV analyses. Compound 12 was isolated for the first time from C. pentagyna. In contrast to C. pentagyna, C. monogyna samples were predominated by 4'''-acetylvitexin-2''-O-rhamnoside (13), which was missing in C. pentagyna. Hence, 13 represents an interesting compound for chemotaxonomy of C. monogyna, whereas the main flavonoids 7, 8, and 12 could be proposed as markers for C. pentagyna. The absence of 7, 8, 12, and 13 in C. laevigata offers an appropriate tool for additional differentiation from C. monogyna and C. pentagyna, and for sample identification and quality control of the three main Crataegus species used in European phytotherapy.
Subject(s)
Crataegus/chemistry , Crataegus/growth & development , Disaccharides/chemistry , Flavonoids/analysis , Flavonoids/chemistry , Glucosides/analysis , Glucosides/chemistry , Kaempferols/chemistry , Biomarkers/analysis , Chromatography, High Pressure Liquid , Magnetic Resonance Spectroscopy , Molecular StructureABSTRACT
In many semi-arid environments of Mediterranean ecosystems, white poplar (Populus alba L.) is the dominant riparian tree and has been used to recover degraded areas, together with other native species, such as ash (Fraxinus angustifolia Vahl.) and hawthorn (Crataegus monogyna Jacq.). We addressed three main objectives: (1) to gain an improved understanding of some specific relationships between environmental parameters and leaf-level physiological factors in these riparian forest species, (2) to compare the leaf-level physiology of these riparian species to each other, and (3) to compare leaf-level responses within native riparian plots to adjacent restoration plots, in order to evaluate the competence of the plants used for the recovery of those degraded areas. We found significant differences in physiological performance between mature and young white poplars in the natural stand and among planted species. The net assimilation and transpiration rates, diameter, and height of white poplar plants were superior to those of ash and hawthorn. Ash and hawthorn showed higher water use efficiency than white poplar. White poplar also showed higher levels of stomatal conductance, behaving as a fast-growing, water-consuming species with a more active gas exchange and ecophysiological competence than the other species used for restoration purposes. In the restoration zones, the planted white poplars had higher rates of net assimilation and water use efficiency than the mature trees in the natural stand. We propose the use of white poplar for the rapid restoration of riparian vegetation in semi-arid Mediterranean environments. Ash and hawthorn can also play a role as accompanying species for the purpose of biodiversity.
Subject(s)
Crataegus/physiology , Ecology , Fraxinus/physiology , Populus/physiology , Crataegus/growth & development , Fraxinus/growth & development , Populus/growth & developmentABSTRACT
This study was carried out to investigate whether spray drift of metsulfuron has a potential to negatively affect hawthorn (Crataegus monogyna) hedgerows near agricultural fields. For this purpose four doses of metsulfuron ranging from 5% to 40% of the field dose (4 g metsulfuron per hectare) were sprayed on trees in seven different hawthorn hedgerows. The actual deposition on the leaves was measured by means of a tracer (glycine). Spraying was conducted both at the bud stage and at early flowering. Leaves, flowers, green berries and mature berries were harvested and the number and weight of each were measured. The spraying at the bud stage caused a highly significant reduction in number and dry weight of berries, whereas it had no effects on leaf and flower production. The berry reduction was close to 100% at actual depositions relevant for spray drift under normal conditions. Spraying at early flowering also significantly reduced berries although the effect was smaller than for the spraying at bud stage. The early flower stage spraying caused no reduction in number and size of leaves. The possible ecological consequence is that metsulfuron spray drift from agricultural fields has a potential to reduce the amount of berries available for frugivorous birds in nearby hedgerows. A potential need for regulatory measures to reduce herbicide spray drift to hedgerows situated near agricultural fields with herbicide use is also indicated.
Subject(s)
Agriculture , Arylsulfonates/toxicity , Crataegus/drug effects , Herbicides/toxicity , Aerosols , Biomass , Crataegus/growth & development , Flowers/drug effects , Flowers/growth & development , Fruit/drug effects , Fruit/growth & development , Plant Leaves/drug effects , Plant Leaves/growth & developmentABSTRACT
Fire blight, caused by the bacterium Erwinia amylovora (Burill Winslow et al.), is the most important bacterial disease in European pear growing. It can cause a lot of damage in some countries on apple and on pear trees in orchards and also in the fruit tree nurseries. In Belgium, the disease is present since 1972. Control of fire blight in Belgian fruit orchards is made on a broad basis of measurements in and around the fruit trees. The use of an antibiotic is allowed for application only during the primary blossom period under strict controlled regulations. The use of antobiotics in agriculture is strongly discussed on the European level today and will probably disappear in the near future. Therefore, the research on fire blight control concentrates on the possibilities of biological control with antagonistic bacteria such as Pantoea agglomerans (Erwinia herbicola), Bacillus subtilis or Pseudomonas syringae strain A 506. The use of Serratine-P, a phage tail-like bacteriocin, produced by Serratia plymiticum, shows an interesting antibacterial activity against Erwinia amylovora. Its mode of action consists in the perforation of the cytoplasmic membrane of the target cell, inducing perturbations in cellular exchanges and a final lysis of the bacterial cell. In this paper some trials are discussed on the use of Serratine-P at different doses and on different infection types on pear trees. The results indicate interesting protection possibilities on blossom- and fruit infections.