Development of a variable number of tandem repeats typing scheme for the bacterial rice pathogen Xanthomonas oryzae pv. oryzicola     

Zhao S  Poulin L  Rodriguez-R LM  Serna NF  Liu SY  Wonni I  Szurek B  Verdier V  Leach JE  He YQ  Feng JX  Koebnik R 《Phytopathology》2012,102(10):948-956

Xanthomonas oryzae pv. oryzicola is an important bacterial pathogen responsible for outbreaks of bacterial leaf streak (BLS) on rice, mostly occurring in Asia and parts of Africa. To better monitor epidemics and assess population structures, efficient tools that allow the precise identification and diagnosis of pathogenic populations are needed. In this study, we explored variable numbers of tandem repeats (VNTR) as a fast, reliable, and cost-effective molecular typing tool. Screening of three X. oryzae pv. oryzicola genome sequences (Philippine strain BLS256, Chinese strain GX01, and Malian strain MAI10) predicted 28 candidate VNTR loci. Primer pairs for polymerase chain reaction (PCR) amplification of all 28 loci were designed and applied to a panel of 20 X. oryzae pv. oryzicola strains originating from Asia and Africa. Sequencing of PCR amplicons revealed 25 robust and polymorphic VNTR loci that are shared among Asian and African X. oryzae pv. oryzicola strains. A dendrogram constructed from 25 VNTR loci indicated that most Asian strains are clearly discriminated from African strains. However, in agreement with previous reports, one strain from Mali is related to Asian strains, pointing to a possible introduction of Asian strains to the African continent. The new VNTR-based tool described here is useful for studies of population structures and epidemiological monitoring of X. oryzae pv. oryzicola.  相似文献   

Flood Retention and Drinking Water Supply – Preventing Conflicts of Interest     

Matthias Maier  Dirk Kühlers  Heinz-Jürgen Brauch  Michael Fleig  Dietrich Maier  Gerhard H. Jirka  Ulf Mohrlok  Ekkehart Bethge  Hans Helmut Bernhart  Boris Lehmann  Gudrun Hillebrand  Jan Wölz  Henner Hollert 《Journal of Soils and Sediments》2006,6(2):113-114

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Comparison of the bioactive compounds and antioxidant potentials of fresh and cooked Polish, Ukrainian, and Israeli garlic     

Gorinstein S  Drzewiecki J  Leontowicz H  Leontowicz M  Najman K  Jastrzebski Z  Zachwieja Z  Barton H  Shtabsky B  Katrich E  Trakhtenberg S 《Journal of agricultural and food chemistry》2005,53(7):2726-2732

Garlic (Allium sativum L.) is an essential part of Polish, Ukrainian, and Israeli cuisine. The aim of this investigation was to compare the changes in bioactive compounds, proteins, and antioxidant potentials in fresh Polish, Ukrainian, and Israeli garlic samples after subjection to cooking temperature. Dietary fiber and essential trace elements were comparable. The antioxidant potentials were determined by four scavenging methods using beta-carotene, 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(*)(+)) radical cation with K(2)S(2)O(8) or MnO(2) assays. Polyphenols, tocopherols, proteins, and antioxidant potentials were higher in Polish garlic, but not significantly (P > 0.05). The SDS- and native-PAGE electrophoretic patterns of all three fresh garlic samples were without significant differences. Most of the proteins were in the molecular mass range of 24-97 kDa, and the more intensive major bands were concentrated at 50 and 12 kDa. The 50 kDa protein nearly disappears and the intensity of the 12 kDa lectin bands slightly decreases during cooking. It was observed that the bioactive compounds, antioxidant potential, and proteins in garlic decrease significantly after 20 min of cooking at 100 degrees C (P < 0.05). In conclusion, (a) the bioactive compounds, electrophoretic patterns, and antioxidant potential of fresh Polish, Ukrainian, and Israeli garlic samples are comparable; (b) garlic samples subjected to 100 degrees C during 20 min preserve their bioactive compounds, antioxidant potential, and protein profile and are comparable with fresh garlic; and (c) fresh garlic should be added to dishes cooked at 100 degrees C in the last 20 min of the cooking process.  相似文献   

Nematicidal effects of the entomopathogenic bacteria Bacillus thuringiensis in soil     

Irina N. Mozgovaya  Boris A. Byzov  Nikolai F. Ryabchenko  Nikolai D. Romanenko  Dmitri G. Zvyagintsev 《Pedobiologia》2002,46(6):558-572

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Growth and Production of Aquatic Mosses in Acidified Lakes of Karelia Republic,Russia     

Ilyashuk  Boris P. 《Water, air, and soil pollution》2002,135(1-4):285-290

Three small acidified lakes (pH of water 5.3–5.9) in Karelia Republic, northwestern Russia, were studied in respect to speciescomposition, phytomass, and morphometric characteristics of aquatic mosses in their dense carpet. The dense moss carpet inlake L1 (mainly, Sphagnum denticulatum Bird.) occurred at a depth of 5.0–7.5 m and covered about 50% of the bottom area. The monospecific moss carpets occurred in lake L2 (Warnstorfia exannulata s. lato) and lake L3 (Fontinalishypnoides Hartm.) at depths of 5.0–7.0 m and 4.5–5.5 m and covered 20 and 13% of the bottom, respectively. The moss phytomass was 43–53 g air-dry mass m^-2 in the lake L2 andlake L3, while it was much higher in lake L1 – 293 g m^-2.Seasonal changes in shoot morphology of S. denticulatum,W. exannulata s. lato and in size and density of leavesalong the shoot axis of F. hypnoides allowed to reconstructthe annual growth and to estimate of growth rates of the mossesin their natural habitat within dense carpet. The absolutely netproduction of the mosses was estimated on the basis of thesedata. In two lakes (L2 and L3), the annual means of absolutelynet production of the aquatic mosses were 32–41 g air-dry massm^-2 yr ^-1, while in the third lake (L1) they weremarkedly higher – 157 g m^-2. The obtained results andcharacteristics of aquatic mosses are compared with those formosses in acidified Lake Grane Langsø in Denmark.  相似文献   

Using Monte Carlo simulations to estimate relative fire ignition danger in a low-to-medium fire-prone region     

Marco Conedera  Damiano TorrianiChristophe Neff  Carlo RicottaSofia Bajocco  Gianni Boris Pezzatti 《Forest Ecology and Management》2011,261(12):2179-2187

A comprehensive assessment of fire ignition danger is nowadays a basic step towards the prioritization of fire management measures. In this study we propose performing a fire selectivity analysis using Monte Carlo simulations to statistically estimate the relative fire ignition danger in a low-to-intermediate fire-prone region such as Canton Ticino, Switzerland. We define fire ignition danger as the likelihood that at a given place a fire will be ignited. For each 25 m × 25 m pixel of the study area, landscape characteristics that may be related to the probability of fire ignition such as vegetation type, elevation, aspect, slope, urban-forest interface were first split into 9-12 categories. The selectivity of each category with respect to fire ignition was then statistically tested by means of Monte Carlo simulations. Finally, we proposed two different approaches for calculating the ignition danger index: cumulating the scores of the Monte Carlo simulations to a final index or producing synthetic scores by performing a principal component analysis of the Monte Carlo results. The validation of the resulting fire danger indices highlights the suitability of both proposed approaches. The PCA-option allows a slightly better discrimination between ignition and non-ignition points and may be of more general application.  相似文献   

Identification of 5 novel feline erythrocyte antigens based on the presence of naturally occurring alloantibodies     

Marie Binvel  Julie Arsenault  Boris Depr  Marie‐Claude Blais 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2021,35(1):234-244

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Short-term watering-distance and symmetry effects on root and shoot growth of bell pepper plantlets   总被引：1，自引：0，他引：1  

Avraham Meiri  Boris NaftalievDavid Shmuel  Hana YechezkelGregory Communar  Shmulik P. Friedman 《Agricultural Water Management》2011,98(10):1557-1568

Drip lines were located at distances ranging from 0 to 60 cm from one or both sides of a row of pepper plantlets, and we monitored the effects on their shoot development during 76 days from transplanting to full-size first fruits, on the final root system, and on the areal water and salt distributions in the upper 15-cm soil layer. The experiment was conducted in a greenhouse with a sandy soil, and excess fresh water (1.9 L d⁻¹ per plant) was applied via short daily irrigations. In addition, the effects of watering distance and symmetry on the potential water uptake rate were analyzed with a coupled-source-sink steady flow and uptake model. Initial faster shoot growth with the one-side system and short distances progressively changed to faster growth with the two-side system and longer watering distances, with the optimum at 30-40 cm. These temporal changes are attributed to temporal changes in the root uptake of irrigation water: small plants with small root systems benefit from the larger water supply to a smaller soil volume provided by the one-side system, whereas larger plants with greater water needs could extract more irrigation water when they developed larger, split root systems in the two-side irrigation. Balanced root systems and maximal shoot growth can be obtained by starting the irrigation with a line on each side, near the plants, and moving the lines after a short time.  相似文献   

SPORE series winner. Computational experiments for science education     

Xie C  Tinker R  Tinker B  Pallant A  Damelin D  Berenfeld B 《Science (New York, N.Y.)》2011,332(6037):1516-1517

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Improved Cryopreservation of Sperm of Paddlefish (Polyodon spathula)     

Ákos  Horváth Béla  Urbányi Steven D.  Mims  William B.  Bean  Boris  Gomelsky Terrence R.  Tiersch 《Journal of the World Aquaculture Society》2006,37(4):356-362

Experiments were performed to improve protocols for sperm cryopreservation of paddlefish (Polyodon spathula), a species for which there has been limited study. The first experiment was conducted to investigate the effects of two extenders (modified Tsvetkova’s extender: mT and modified Hanks’ balanced salt solution: mHBSS) in combination with methanol (MeOH) and dimethyl sulfoxide in two concentrations (5 and 10%) on the postthaw motility and fertilization rates of cryopreserved sperm. The highest postthaw motility (85 ± 5%) was observed when sperm were frozen using mT extender with 10% MeOH as cryoprotectant. Extenders (P = 0.0018) and cryoprotectants (P = 0.0040) each had a significant effect on the postthaw motility of paddlefish sperm. The highest fertilization (80 ± 3%) was found when eggs were fertilized with sperm frozen with mT extender in combination with 10% MeOH. However, there was no significant difference among fertilization rates when MeOH was used as a cryoprotectant in either concentration or in combination with either mT or mHBSS extenders. In the second experiment, 4000 eggs were fertilized with the pooled contents of five straws of thawed sperm (total volume of 1.25 mL) using mT extender in combination with 5% MeOH, and hatch rates as high as 79 ± 5% were observed. A third experiment was also conducted to clarify the role of MeOH concentration; however, no significant difference was found among fertilization and hatch rates when either 5 or 10% MeOH was used as a cryoprotectant. These results suggest that MeOH is a safe and reliable cryoprotectant for freezing of paddlefish sperm and obtaining viable postthaw sperm for consistent fertilization and hatch rates. Further, this experimental protocol is relatively simple and applicable for commercial hatchery production of paddlefish.  相似文献