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Nazmul H. ANTOR Shamim MIA Md. M. HASAN Nowrose J. LIPI Keiji JINDO Miguel A. SANCHEZ-MONEDERO Md. H. RASHID 《土壤圈》2023,33(4):659-669
Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces. However, little is known about how the application of activated biochars mixed with urea influences nitrogen(N) mineralization and crop performance in paddy fields. Here, a sawdust-derived fresh biochar (FBC)(ca. 400?C) was activated chemically with 15%hydrogen peroxide and biologically with a nutri... 相似文献
2.
In growth chamber experiments, tralkoxydim activity against Avena fatua was significantly reduced by addition of metsulfuron methyl to the spray solution. This was apparent particularly at low rates of tralkoxydim (e.g., 125 g a.i.ha?1) and at high rates of metsulfuron methyl (8 or 12 g a.i. ha?1). Metsulfuron methyl alone reduced A. fatua growth significantly, Chlorsul-furon, which did not reduce A. fatua growth at rates of up to 33 g a.i. ha?1, caused only a slight loss in tralkoxydim activity. When applied in combination, metsulfuron methyl reduced the uptake of foliar-applied 14C-tralkoxydim 6 h after application, but did not affect uptake or translocation of 14C-tralkoxydim at subsequent sampling times. In in vitro assays, metsulfuron methyl at 10 or 100 nM in the assay medium had no effect on acetyl-coenzyme A carboxylase (ACCase) activity in A.fatua, nor did it interfere with the inhibition of ACCase by tralkoxydim. In addition, treatment of A. fatua plants with metsulfuron methyl at 4, 8 or 12 g ha?1 did not reduce the level of extractable ACCase activity when the plants were harvested 24–96 h after spraying. Thus, no apparent physiological or biochemical basis for the antagonism of tralkoxydim was identified. The temporary growth inhibition induced by metsulfuron methyl may be of sufficient duration for most of the tralkoxydim to be metabolized to inactive products, thereby reducing tralkoxydim-induced injury. Antagonisme entre le metsulfuron-methyl et l'activité de la tralkoxydime sur Avena fatua Dans des essais en chambres climatiques, l'activité de la tralkoxydime contre Avena fatua a été significativement réduite par l'adjonction de metsulfuron-methyl dans la bouillie de pulvérisation. Ceci est particulièrement apparent à de faibles doses de tralkoxydime (ex. 125 g. m.a. ha?1) et à de faibles doses de metsulfuron-methyl (8 à 12 g m.a. ha?1). Le metsulfuron-methyl seul réduit la croissance d'Avena fatua. Le chlorsulfuron qui ne réduit pas la croissance d'Avena fatuaà des doses jusqu'à 33 g m.a. ha?1 cause seulement une faible perte d'efficacité chez la tralkoxydime. Quand il est appliqué en mélange, le metsulfuron-méthyl a réduit l'absorption de la C14 tralkoxydime appliquée sur les feuilles 6 h après l'application, mais n'a pas affecté l'absorption et le transport de la C14 tralkoxydime aux autres temps d'échantillonage ultérieurs. Dans les essais in vitro, le metsulfuron-methyl à 10 ou 100 nm dans le milieu d'essai n'a pas eu d'effet sur l'activité de l'acetyl coenzyme A carboxylase (ACCase), ni n'a interféré avec l'inhibition de l'ACCase par la tralkoxydime. En outre, le traitement d'Avena fatua avec du metsulfuron-methyl a 4, 8 ou 12 g ha?1 n'a pas réduit le niveau d'activité d'ACCase quand les plantes étaient récoltées de 24 à 96 h après l'application. Ainsi aucune base apparente physiologique ou biochimique pour l'antagonisme de la tralkoxydime n'a été identifiée. L'inhibition temporaire de la croissance induite par le metsulfuron-methyl peut être d'une durée suffisante pour que la plus grande partie de la tralkoxydime soit métabolisée en produits inactifs, et de ce fait réduit les effets induits par la tralkoxydime. Antagonismus von Metsulfuron-methyl auf die Wirkung von Tralkoxydim auf Avenua fatua In Phytotron-Versuchen wurde die Wirkung von Tralkoxydim auf Avena fatua durch Zugabe von Metsulfuron-methyl in die Spritzbrühe signifikant herabgesetzt, besonders bei niedrigen Tralkoxydim-Dosen (z. B. 125 g AS ha?1) und bei hohen Metsulfuron-methyl-Dosen (8 oder 12 g AS ha?1). Metsulfuron-methyl allein setzte das Wachstum von Avena fatua signifikant herab. Mit Chlorsulfuron, das das Wachstum von Avena fatua bis 33 g AS ha?1 nicht verminderte, ließ sich die Wirkung von Tralkoxydim nur wenig beeinträchtigen. In Kombination reduzierte Metsulfuron-methyl die Blattaufnahme von 14C-Tralkoxydim 6 h nach der Applikation, aber bei späteren Probennahmen waren Aufnahme und Translokation von 14C- Tralkoxydim nicht beeinträchtigt. In In-vitro-Versuchen blieben 10 oder 100 mm Metsulfuron in der Versuchslösung ohne Wirkung auf die Aktivität der Acetyl-Coenzym-A-Carboxylase (ACCase) in Avena fatua, es wirkte auch nicht auf die Hemmung der ACCase durch Tralkoxydim. Auch eine Behandlung von Avena-fatua-Pflanzen mit 4, 8 oder 12 g AS ha?1 Metsulfuron-methyl setzte nach 24 bis 96 h die ACCase-Aktivität nicht herab. So konnte keine offensichtliche physiologische oder biochemische Basis für den Antagonismus von Tralkoxydim gefunden werden. Die durch Metsulfuron-methyl induzierte zeitweilige Wuchshemmung kann lang genug sein, daß das meiste Tralkoxydim zu inaktiven Produkten abgebaut wird, so daß seine Wirksamkeit reduziert wird. 相似文献
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Avena fatua L. populations from numerous fields in Alberta have simultaneously developed resistance to recommended rates of two dissimilar herbicides, triallate and difenzoquat. We used exogenous applications of gibberellic acid (GA3 ) to investigate the possibility that endogenous gibberellins were involved in the A. fatua 's resistance mechanism. For control plants, without applied GA3 , shoots of the most resistant (R) populations emerged more rapidly and elongated faster than shoots of the susceptible (S) populations. Increases in shoot elongation in response to exogenous GA3 were significantly lower in R populations compared with S populations. This suggests that R populations may have elevated endogenous gibberellin levels, relative to S populations. Additionally, inhibition of S population shoot elongation and shoot anatomical abnormalities caused by relatively low concentrations of triallate and difenzoquat could be prevented by exogenous application of GA3 . These results suggest that there may be a phytohormonal involvement in the mechanism of triallate/difenzoquat resistance in A. fatua . That is, higher endogenous gibberellin levels in R populations may result in meristematic growth that is rapid enough to preclude phytotoxic levels of these herbicides from reaching the shoot meristem, which is the likely site of action. 相似文献
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A bacteriocin-producing strain Streptococcus bovis J2 40-2 was isolated from traditional fermented milk 'Dahi' in Bangladesh. Despite its narrow antimicrobial spectrum, it showed strong antimicrobial activity against extremely challenging and problematic organisms in foods, such as Listeria monocytogenes . Bacteriocin was sensitive to several proteolytic enzymes and showed antimicrobial activity over a wide pH range of 2.0–10.0. It was stable when heated to 110°C for 20 min, but lost 25% of its activity when heated to 121°C for 15 or 20 min. Optimum bacteriocin production (5600 AU/mL) was achieved when the strain was cultured at 37°C for 24 h in MRS medium rather than in TYLG, GM17, or skim milk medium. Bacteriocin was partially purified by ammonium sulfate precipitation (80% saturation), dialysis (cut-off MW: 3500) and gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that bacteriocin had a molecular weight of approximately 4.5 kDa. 相似文献
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Hamna SALEEM Mahtab AHMAD Jamshaid RASHID Munir AHMAD Mohammad I. AL-WABEL Memuna AMIN 《土壤圈》2022,32(2):283-293
There are numerous studies conducted on biochar for its carbon (C) sequestration potential;however,there are limited studies available on the behavior of salt-affected soils related to biochar application.Therefore,more studies are needed to elucidate the mechanisms through which biochar affects saline soil properties.In this study,biochars were produced from solid waste at pyrolysis temperatures of 300,500,and 700?C (BC300,BC500,and BC700,respectively)and applied to a saline soil to evaluate their impacts on soil carbon dioxide (CO2) efflux,C sequestration,and soil quality.A soil incubation experiment lasting for 107 d was conducted.The results showed that soil CO2 efflux rate,cumulative CO2 emission,active organic C (AOC),and organic matter (OM)significantly increased with BC300 application to a greater extent than those with BC500 and BC700 as compared to those in the no-biochar control (CK).However,soil C non-lability did not significantly increase in the treatments with biochars,except BC700,as compared to that in CK.Besides improving the soil quality by increasing the soil AOC and OM,BC300 showed positive impacts in terms of increasing CO2 emission from the saline soil,while BC500 and BC700 showed greater potentials of sequestering C in the saline soil by increasing the soil non-labile C fraction.The recalcitrance index (R50) values of BC500 and BC700 were>0.8,indicating their high stability in the saline soil.It could be concluded that biochars pyrolyzed at high temperatures (?500?C)could be suitable in terms of C sequestration,while biochars pyrolyzed at low temperatures (?300?C) could be suitable for improving saline soil quality. 相似文献
6.
Owais Ali WANI Shamal Shasang KUMAR Nazir HUSSAIN Anas Ibni Ali WANI Subhash BABU Parvej ALAM Megna RASHID Simona Mariana POPESCU Sheikh MANSOOR 《土壤圈》2023,33(2):250-267
Carbon(C) is a key constitutive element in living organisms(plants, microbes, animals, and humans). Carbon is also a basic component of agriculture because it plays a dynamic role in crop growth, development, nutrient cycling, soil fertility, and other agricultural features. The presence of C enhances soil physical, chemical, and biological properties. The C cycle supports all life on the Earth by transferring C between living organisms and the environment. The global climate is changing, and th... 相似文献
7.
- Human activities are an increasing threat to Neotropical freshwater ecosystems, with the potential extinction of thousands of aquatic species. Despite this, knowledge about the effectiveness of protected area networks in protecting aquatic insects in this biogeographical region is very limited.
- Cuba supports the highest diversity of aquatic insects in the Antilles, with a large number of endemics.
- A gap analysis was conducted to assess the effectiveness of the National System of Protected Areas of Cuba (NSPAC) in the conservation of Cuban diving beetles (family Dytiscidae). This involved considering the areas with the highest potential species richness, estimated by using species distribution models with three different approaches (MaxEnt, Random Forest and Support Vector Machine), and the known localities of endemic species.
- The highest potential species richness of Dytiscidae in Cuba is predicted to occur in the low–medium altitude of the eastern mountain areas. Although most of these areas occur inside the NSPAC, several areas of potential high species richness are currently unprotected. It is recommended that sampling programmes are carried out in areas with high predicted species richness to validate the species distribution models.
- The distribution of three Cuban endemic species (Copelatus barbouri, Desmopachria glabella and Celina cubensis) lies completely outside of the NSPAC. Despite their conservation interest as threatened endemic species, they are currently unprotected.
- To improve the conservation of freshwater biodiversity in Cuba it is recommended that (i) the NSPAC network is extended to protect areas supporting endemic species and those with the highest potential species richness that are currently unprotected, and (ii) a whole-catchment management approach, specifically to maintain natural flows, should be adopted, especially in the mountainous areas of eastern Cuba.
8.
ABDUR RASHID NANCY H. FURNESS BRIAN E. ELLIS MAHESH K. UPADHYAYA 《Weed Biology and Management》2005,5(3):143-149
The leaching of phenolics from decoated seeds, seed coats and pericarps of hound's-tongue ( Cynoglossum officinale L.), factors affecting leaching, and seed germination and seedling growth inhibitory activities of the leachate were investigated. Embryonic axes and cotyledons contained a large amount of methanol-soluble phenolic substances. Decoated seeds released phenolics into an aqueous incubation medium and this solution was capable of inhibiting root elongation of several grassy and broadleaf species, but not of hound's-tongue. The leachate and the phenolic fraction of the leachate inhibited germination of bluebunch wheatgrass ( Pseudoroegnaria spicata (Pursh) A. Löve [syn. Agropyron spicatum (Pursh) Scribn. and J. G. Sm.]). The non-phenolic fraction of the leachate did not inhibit seed germination or root and shoot elongation of bluebunch wheatgrass. Low oxygen and an increasing temperature significantly increased the amount of phenolic substances leached from decoated seeds. Increased leaching of phenolic substances related to an increasing temperature was associated with the loss of seed viability. Further investigation of the role of water-extractable hound's-tongue seed phenolics in the interaction of this species with its biotic environment under field conditions is needed to determine the ecological significance of these findings. 相似文献
9.
Luqman RIAZ Tariq MAHMOOD YANG Qingxiang Muhammad Wahab YASIR Audil RASHID Mark S.COYNE Elisa D'ANGELO 《土壤圈》2019,(5)
<正>Dear Editor,Fluoroquinolones(e.g.,ciprofloxacin(CIP),enrofloxacin(ENR),and levofloxacin(LEV))are an extensively used family of antibiotics prescribed for various infections;however,they are also increasingly used 相似文献
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