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1.
Molecules ; 27(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36557869

RESUMO

Application of a combined atmospheric plasma/UV laser to cotton fabrics impregnated with selected non-durable flame retardants (FRs) has shown evidence of covalent grafting of the latter species on to cotton fibre surfaces. As a result, an increase in their durability to water-soaking for 30 min at 40 °C has been recorded. Based on previous research plasma gases comprising Ar80%/CO220% or N280%/O220% were used to pre-expose cotton fabric prior to or after FR impregnation to promote the formation of radical species and increased −COOH groups on surface cellulosic chains, which would encourage formation of FR-cellulose bonds. Analysis by scanning electron microscopy (SEM/EDX), X-ray photoelectron spectroscopy (XPS) and thermal analysis (TGA) suggested that organophosphorus- and nitrogen- containing flame retarding species in the presence of the silicon-containing molecules such as 3-aminopropyltriethoxy silane (APTS) resulted in formation of FR-S-O-cellulose links, which gave rise to post-water-soaking FR retentions > 10%. Similarly, the organophosphorus FR, diethyl N, N bis (2-hydroxyethyl) aminomethylphosphonate (DBAP), after plasma/UV exposure produced similar percentage retention values possibly via (PO).O.cellulose bond formation, While none of the plasmas/UV-treated, FR-impregnated fabrics showed self-extinction behaviour, although burning rates reduced and significant char formation was evident, it has been shown that FR durability may be increased using plasma/UV treatments.


Assuntos
Retardadores de Chama , Têxteis , Fibra de Algodão , Microscopia Eletrônica de Varredura , Celulose
2.
Environ Eng Sci ; 36(7): 833-842, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31346305

RESUMO

Traditional wastewater management uses end-of-pipe approaches to remove pollutants in wastewater before discharge. Although effective in human health protection for decades, this approach of removal and disposal requires a high investment of energy and materials and overlooks the values of the key nutrients in wastewater such as phosphorus (P). Phosphorus in wastewater comes from the human metabolites of food, resulted from crop uptakes of fertilizer that ultimately derived from phosphate rock (PR). PR, however, could be depleted in this century, which would lead to a global food crisis. To address the question whether nutrient recovery is indeed a more efficient strategy from a system perspective and provides more benefits to society, this research compares fertilizer production from struvite to the traditional commercial fertilizers (e.g., diammonium phosphate, DAP). Emergy defined as the available energy required directly and indirectly through all transformations to make a product, process, or service is the tool used for system analysis in this study. Emergy accounting provides system analysis of total resource use and whole system efficiency. The results show that struvite production uses one order of magnitude less emergy than DAP production to produce one unit of fertilizer, indicating that struvite production is a more efficient process. This research sheds light on alternative nutrient management through nutrient recovery, which may achieve economic and environmental benefits and overall higher system efficiency.

3.
J Sci Food Agric ; 97(6): 1733-1739, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27448093

RESUMO

BACKGROUND: Low phosphorus (P) availability to wheat from commercial fertilizers is one of the reasons for lower grain yield and hence justifies search for more efficient P source under alkaline calcareous soils. RESULTS: Phosphoric acid (PA) and diammonium phosphate (DAP), applied through conventional and modified methods, were assessed for P supply and wheat yield in a calcareous soil. Under laboratory conditions, pre-incubated soil with 70 mg P kg-1 soil as PA and DAP was assessed for solution P (Cp ) for 4 weeks. Phosphorus sorption data were fitted using the Freundlich model for describing analyzed sorption in soil incubated with or without DAP and PA. The fitted model equations exhibited comparatively higher effluxes of P from the solution system in control treatment. Compared to DAP, lower quantities (19.6%) of P for PA-treated soil were required for producing optimum P concentration in soil solution, i.e. 0.2 mg P L-1 . The greenhouse study involved 32 P tracer technique to quantify the proportion of applied P derived by wheat from fertilizer or soil. The results showed that P derived from fertilizer was highest (47.5%) in PA placement, while the lowest (31.5%) was in DAP broadcast treatment. The field study also showed similar trends to that of the greenhouse study. The PA placement treatment resulted in highest (23.4%) phosphorus use efficiency, whereas the lowest one (17.1%) was recorded for DAP broadcast treatment. CONCLUSION: PA proved to be a better P source than DAP for improving P content and achieving higher yield and recovery of applied P by wheat grown in alkaline calcareous soils. © 2016 Society of Chemical Industry.


Assuntos
Ácidos Fosfóricos/metabolismo , Fósforo/metabolismo , Triticum/metabolismo , Agricultura , Transporte Biológico , Fertilizantes/análise , Solo/química
4.
Appl Microbiol Biotechnol ; 100(15): 6653-6660, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26883345

RESUMO

Exploration of cost-effective fermentation substrates for efficient lactate production is an important economic objective. Although some organic nitrogen sources are also cheaper, inorganic nitrogen salts for lactate fermentation have additional advantages in facilitating downstream procedures and significantly improving the commercial competitiveness of lactate production. In this study, we first established an application of diammonium phosphate to replace yeast extract with a reduced 90 % nitrogen cost for a thermotolerant Bacillus coagulans strain. In vivo enzymatic and transcriptional analyses demonstrated that diammonium phosphate stimulates the gene expression of L-lactate dehydrogenase, thus providing higher specific enzyme activity in vivo and increasing L-lactic acid production. This new information provides a foundation for establishing a cost-effective process for polymer-grade L-lactic acid production in an industrial setting.


Assuntos
Bacillus coagulans/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Fosfatos/metabolismo , Bacillus coagulans/enzimologia , Meios de Cultura/química , Fermentação , Expressão Gênica/efeitos dos fármacos , L-Lactato Desidrogenase/genética
5.
Front Plant Sci ; 14: 1240313, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023856

RESUMO

Maize cropping systems need to be re-designed, within a sustainable intensification context, by focusing on the application of high-use efficiency crop practices, such as those that are able to enhance an early plant vigor in the first critical growth stages; such practices could lead to significant agronomic and yield benefits. The aim of this study has been to evaluate the effects of the cultivation of hybrids with superior early vigor, of the distribution of starter fertilizers at sowing, and of the seed application of biostimulants on promoting plant growth and grain yield in full factorial experiments carried out in both a growth chamber and in open fields. The greatest benefits, in terms of plant growth enhancement (plant height, biomass, leaf area) and cold stress mitigation, were detected for the starter fertilization, followed by the use of an early vigor hybrid and a biostimulant seed treatment. The starter fertilization and the early vigor hybrid led to earlier flowering dates, that is, of 2.1 and 2.8 days, respectively, and significantly reduced grain moisture at harvest. Moreover, the early vigor hybrid, the starter NP fertilization, and the biostimulant treatment increased grain yield by 8.5%, 6.0%, and 5.1%, respectively, compared to the standard hybrid and the untreated controls. The combination of all the considered factors resulted in the maximum benefits, compared to the control cropping system, with an increase in the plant growth of 124%, a reduction of the sowing-flowering period of 5 days, and a gain in grain yield of 14%. When choosing the most suitable crop practice, the diversity of each cropping system should be considered, according to the pedo-climatic conditions, the agronomic background, the yield potential, and the supply chain requirements.

6.
Front Plant Sci ; 14: 1240310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023909

RESUMO

The sustainable intensification of maize-based systems may reduce greenhouse-gas emissions and the excessive use of non-renewable inputs. Considering the key role that the microbiological fertility has on crop growth and resilience, it is worth of interest studying the role of cropping system on the rhizosphere bacterial communities, that affect soil health and biological soil fertility. In this work we monitored and characterized the diversity and composition of native rhizosphere bacterial communities during the early growth phases of two maize genotypes of different early vigor, using a nitrogen (N)-phosphorus (P) starter fertilization and a biostimulant seed treatment, in a growth chamber experiment, by polymerase chain reaction-denaturing gradient gel electrophoresis of partial 16S rRNA gene and amplicon sequencing. Cluster analyses showed that the biostimulant treatment affected the rhizosphere bacterial microbiota of the ordinary hybrid more than that of the early vigor, both at plant emergence and at the 5-leaf stage. Moreover, the diversity indices calculated from the community profiles, revealed significant effects of NP fertilization on richness and the estimated effective number of species (H2) in both maize genotypes, while the biostimulant had a positive effect on plant growth promoting community of the ordinary hybrid, both at the plant emergence and at the fifth leaf stage. Our data showed that maize genotype was the major factor shaping rhizosphere bacterial community composition suggesting that the root system of the two maize hybrids recruited a different microbiota. Moreover, for the first time, we identified at the species and genus level the predominant native bacteria associated with two maize hybrids differing for vigor. These results pave the way for further studies to be performed on the effects of cropping system and specific crop practices, considering also the application of biostimulants, on beneficial rhizosphere microorganisms.

7.
Environ Sci Pollut Res Int ; 30(17): 49060-49074, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36763265

RESUMO

With increasing demand for agricultural production, chemical fertilizers are now being intensively manufactured and used to provide readily available nutrients in larger quantities, which often leach out and contaminate the groundwater source. At the same time, effluents from fertilizer plants also pollute water bodies, when disposed of without proper treatment. The present study evaluates nitrogen and phosphorus removal efficiencies in a single-stage aerobic moving bed bioreactor (MBBR) from diammonium phosphate (DAP)-spiked wastewater containing no organic carbon. To date, no similar study has been undertaken that treats fertilizer plant effluent or agricultural runoff without the aid of external carbon, where organic carbon is hypothesized to be supplied from endogenous degradation of biomass. Both denitrification and phosphorus removal occurs in the anoxic zones of deeper layers of the biofilm. The present investigation demonstrates the feasibility of the processes with the requirement of a two-stage MBBR for effective simultaneous nitrification, denitrification, and phosphorus removal (SNDPr) together with a polishing technology to bring down the phosphorus concentration within limits. A novel bio-carrier designed for efficient SND was used in the study, with a carrier filling ratio of 35% that supported the formation of deep biofilms creating anoxic zones in the inner surface. Identification of the bacterial species reflects the occurrence of simultaneous nitrification, denitrification, and phosphorous removal (SNDPr) in the reactor. A maximum ammonium nitrogen removal efficiency of 98% was recorded with 95% total nitrogen removal, 69% phosphorus removal, and 85% SND efficiency, indicating the applicability of the process with a tertiary phosphorus removal unit to lower the nutrient concentration of effluents prior to disposal.


Assuntos
Nitrificação , Águas Residuárias , Desnitrificação , Fertilizantes , Fósforo/metabolismo , Biofilmes , Eliminação de Resíduos Líquidos , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Nitrogênio/metabolismo , Carbono/metabolismo
8.
Microorganisms ; 11(7)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37512920

RESUMO

Inoculation with phosphate-solubilizing bacteria (PSB) and the application of phosphorus (P) sources can improve soil P availability, enhancing the sustainability and efficiency of agricultural systems. The implementation of this technology in perennial grasses, such as Kikuyu grass, for cattle feed in soils with high P retention, such as Andisols, has been little explored. The objective of this study was to evaluate the productive response of Kikuyu grass and soil P dynamics to BSF inoculation with different P sources. The experiment was conducted on a Kikuyu pasture, which was evaluated for 18 months (September 2020 to March 2022). Three P fertilizers with different solubility levels were applied: diammonium phosphate (DAP) (high-solubility), rock phosphate (RP), and compost (OM) (low-solubility). Moreover, the inoculation of a PSB consortium (Azospirillum brasilense D7, Rhizobium leguminosarum T88 and Herbaspirillum sp. AP21) was tested. Inoculation with PSB and fertilization with rock phosphate (RP) increased soil labile P and acid phosphomonoesterase activity. Increased grass yield and quality were related with higher soil inorganic P (Pi) availability. This study validated, under field conditions, the benefits of PSB inoculation for soil P availability and Kikuyu grass productivity.

9.
Saudi J Biol Sci ; 29(1): 255-260, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35002416

RESUMO

Phosphorous (P) plays the prominent role to promote the plants storage functions and structural roles, as it is recognized as a vital component of ADP, ATP, Cell wall as well as a part of DNA. Soils acts as the sink to supply P to plants because soil pH and its physical condition are the main factor which regulate the solubility and availability P element. Phosphorus is not deficient in Pakistani soils but its availability to plants is the serious matter of concern. A pot experiment was conducted to evaluate P dynamics in two different soil series of Pakistan (Bahawalpur and Lyallpur) using Maize as test crop. The treatments applied were T0: Control (without any fertilizer), T1: Recommended DAP @648 mg pot-1, T2: Half dose DAP @324 mg pot-1, T3: Recommended rate of TSP @900 mg pot-1, T4: Half dose TSP @450 mg pot-1. Soil analysis showed that Bahawalpur soil has sandy clay loam texture with 33% clay and Lyallpur series has sandy loam texture with 15.5% clay; furthermore, these soil contain 4.6 and 2.12% CaCO3 respectively. Results showed an increase in P concentration in roots (23 mg kg-1) with the application of half dose of TSP in Lyallpur series and lowest in Bahawalpur series (14.6 mg kg-1) at recommended dose of DAP. Concentration of P in shoots responded the same; increase at half dose of TSP (16.7 mg kg-1) and lowest at full dose of DAP in Bahawalpur series as (15.58 mg kg-1). Adsorbed P (17 mg kg-1) was recorded highest in Bahawalpur soil with more clay amount in pot with DAP application but lower in Lyallpur soil series (14 mg kg-1) with the application of applied TSP. The PUE was recorded highest in Lyallpur series with the application of half dose of TSP and it was 61% more than control and was Highest in Bahawalpur series was with the application of recommended dose of DAP is 72% more than control treatment. On estimation; results showed that applied sources made an increase in P availability than control, but TSP gave better P uptake than DAP unless of rates applied. Soil of Lyallpur series showed better uptake of P and response to applied fertilizers than Bahawalpur series which showed more adsorption of P by high clay and CaCO3 amount. Conclusively, the study suggested that soil series play a crucial role in choosing fertilizer source for field application.

10.
Environ Pollut ; 311: 119977, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35987285

RESUMO

Both cadmium (Cd) toxicity and water limited stress in crop plants are serious concerns worldwide while little is known about the impact of various phosphorus (P) sources on Cd accumulation in cereals especially under water limited stress. A study was conducted to explore the efficiency of three frequently available P fertilizers on Cd accumulation in wheat under different soil moisture levels. Three different P sources including diammonium phosphate (DAP), single super phosphate (SSP), and nitrophos (NP) were applied in the soil with three levels (0, 50 and 100 mg/kg). The drought stress was applied to half treatments during the latter growth stages of wheat and plants were harvested at maturity. The results demonstrated that water-limited stress decreased the growth and yield of plants than respective treatments without water stress. P supply increased the growth of wheat irrespective of water-limited stress. The effect on growth and yield varied with the sources and levels of P and maximum effects was observed in DAP treatment (100 mg/kg). The P amendments enhanced the leaf photosynthesis and activities of SOD, POD, CAT and decreased the leaf oxidative burst. Water limited stress enhanced the Cd concentrations in shoots, roots, and grains whereas P amendments minimized the Cd concentrations and enhanced the P concentrations in these parts of plants. The results obtained demonstrated that P supply in the form of DAP might be effective in minimization of Cd in grains and can be used for safe cultivation of metal-contaminated soils.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Fósforo/farmacologia , Solo , Poluentes do Solo/análise , Triticum
11.
Nat Prod Res ; 36(1): 63-70, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32375514

RESUMO

The degradation of materials commonly starts on the surface of the object and proceeds towards inside through pores, increasing fractures and lesions. To restore mechanical and aesthetic characteristics, it is necessary by the application of consolidants to fill these weak points so that they become inaccessible to corrosive agents. Greater is the amount of consolidant that penetrates, greater the efficiency of the restoration. This is the limiting factor of many approaches which due to very tight pores result not fully successful. The consolidation under vacuum can help to pass these difficulties. So we have adopted it to restore Macco samples and tested to consolidate archaeological bones. The samples were consolidated by complete immersion under vacuum (-700 mm Hg), in a consolidant solution containing 8% w/V of diammonium phosphate. The success of the application to both the kind of samples is shown by microscope images, SEM-EDAX analysis, and weight variation.


Assuntos
Vácuo
12.
J Agric Food Chem ; 70(29): 8942-8954, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35835727

RESUMO

Exogenous application of nitrogen (N) and phosphate (P) has been demonstrated to alleviate apple replant disease (ARD). Yet, the effect of controlled-release diammonium phosphate (C-DAP), which continuously supply N and P for ARD control, is still poorly understood. Applying C-DAP markedly alleviated the typical symptoms of ARD. C-DAP maintained soil N and P at relatively high and stable levels during the entire growth period of the replanted seedlings, thus, limiting the copy number of the four key pathogenic Fusarium species that cause ARD. Particularly, continuously supplying N and P by C-DAP established a higher fungal diversity than that of conventional diammonium phosphate and induced the fungal community to be more similar to fumigated soil. The positive effect of C-DAP originated from the synergistic effects of regulating microorganisms and enhancing the resistance of the plant caused by a continuous nutrient supply. These findings provide a new perspective in the management of soil-borne diseases.


Assuntos
Malus , Microbiota , Preparações de Ação Retardada , Fosfatos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Solo , Microbiologia do Solo
13.
Carbohydr Polym ; 259: 117679, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673984

RESUMO

Sufficient hydroxyl moiety, ease of accessibility, biodegradability and reaction compatibility with other molecules make starch a basic ingredient for polymeric synthesis and to prepare encapsulated controlled release fertilizers. This article aims to prepare biodegradable clay-polymeric (starch/PVA) blended encapsulating films (CPSBs) from starch/PVA and economically feasible clay-fractioned bentonite for CPSB-encapsulated diammonium phosphate (DAP) production. The XRD, TEM and FTIR spectroscopy recognized the compatibility of bentonite with starch/PVA blend; several micropores in CPSB surface was visible through SEM. Relative crystallinity index, density of CPSBs increased with increasing bentonite content (0-20 wt%); but, porosity, water absorption was decreased. Half-life of CPSB-10 was 37.4, 40.1 and 51.9 days with Aspergillus awamori, Trichoderma viride and uninoculated soil, respectively. Nitrogen (N) and phosphorus (P) release data from CPSB-encapsulated-DAP and uncoated DAP fitted well to Korsmeyer-Peppas model. Overall, greater bentonite content stabilizes the CPSB structure and CPSB-encapsulation reduced the N and P release from DAP.

14.
Front Microbiol ; 11: 1264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670223

RESUMO

The fermentation of apple juice into hard cider is a complex biochemical process that transforms sugars into alcohols by yeast, of which Saccharomyces cerevisiae is the most widely used species. Among many factors, hydrogen sulfide (H2S) production by yeast during cider fermentation is affected by yeast strain and yeast assimilable nitrogen (YAN) concentration in the apple juice. In this study, we investigated the regulatory mechanism of YAN concentration on S. cerevisiae H2S formation. Two S. cerevisiae strains, UCD522 (a H2S-producing strain) and UCD932 (a non-H2S-producing strain), were used to ferment apple juice that had Low, Intermediate, and High diammonium phosphate (DAP) supplementation. Cider samples were collected 24 and 72 h after yeast inoculation. Using RNA-Seq, differentially expressed genes (DEGs) identification and annotation, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, we found that gene expression was dependent on yeast strain, fermentation duration, H2S formation, and the interaction of these three factors. For UCD522, under the three DAP treatments, a total of 30 specific GO terms were identified. Of the 18 identified KEGG pathways, "Sulfur metabolism," "Glycine, serine and threonine metabolism," and "Biosynthesis of amino acids" were significantly enriched. Both GO and KEGG analyses revealed that the "Sulfate Reduction Sequence (SRS) pathway" was significantly enriched. We also found a complex relationship between H2S production and stress response genes. For UCD522, we confirm that there is a non-linear relationship between YAN and H2S production, with the Low and Intermediate treatments having greater H2S production than the High treatment. By integrating results obtained through the transcriptomic analysis with yeast physiological data, we present a mechanistic view into the H2S production by yeast as a result of different concentrations of YAN during cider fermentation.

15.
Food Res Int ; 133: 108707, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32466922

RESUMO

A particular challenge to making wine from Pinot noir grapes is the delicate flavor, light color and poor ageing potential of the wine. Conventional Pinot noir must preparations were compared with those made using a skin-based supplement to assess the impact on non-bleachable (sulfur resistant) pigments in the wine. When supplemented with either fresh grape pomace of Pinot noir, Pinot gris or Chardonnay grapes; Pinot noir grape marc or a commercial liquid grape skin extract, the additional seeds and pulp from the supplements were shown to compromise the development of stable pigments in the wine. To compare the relative merits of tannin derived from grape skins and seeds, the supplements used in a parallel experiment were the skins alone of the same three grape varieties and at six months bottle age, the stable pigment concentration was found to exceed the amount attributable to the supplement. A third experiment used fermented grape skins as the supplement, with 85% of the supplementary anthocyanin recovered as stable pigment complexes in the wine. Notably, this series of experiments showed that supplements containing grape seeds appeared to compromise non-bleachable pigment formation in the wine while skin only supplements stimulated their development.


Assuntos
Pigmentação/efeitos dos fármacos , Epiderme Vegetal/química , Sementes/química , Vitis , Vinho , Antocianinas/análise , Fermentação , Taninos/análise
16.
Environ Sci Pollut Res Int ; 26(31): 32276-32284, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31598923

RESUMO

Fixation reactions reduce the concentration of soluble phosphorus (P) and affect crop growth in alkaline calcareous soils. In lab and greenhouse studies, phosphoric acid (PA) or diammonium phosphate (DAP) were evaluated at various P rates (0, 18, 36 and 54 mg kg-1 soil), either as non-mix (designated as NM-PA and NM-DAP, respectively) or after premixing with farmyard manure (FYM) at 400 mg kg-1 soil (designated as PM-PA and PM-DAP, respectively). The amended soil was incubated at 25 °C and 70% water holding capacity for 7 weeks; thereafter, 32P dynamics were measured using the Freundlich kinetic model. A greenhouse study was also conducted using the same thirteen treatments (as used in incubation experiment) and wheat cultivar (Galaxy 2013) was grown following standard agronomic practices. The results showed that application of PM-PA at the highest rate, which caused maximum change in Pr (ΔPr = 59%) in laboratory condition, also produced maximum P uptake by grain (190.3 mg pot-1) and grain yield (44.1 g pot-1) of wheat in greenhouse experiment. Similarly, regression analysis showed that an increase in Pr values caused a corresponding increase in crop parameters. The results suggested that pre-mixing P fertilizer with FYM could be a viable technique to increase P supply and enhance productivity of wheat in alkaline calcareous soils.


Assuntos
Grão Comestível/química , Fertilizantes/análise , Fósforo/análise , Triticum/crescimento & desenvolvimento , Esterco , Fosfatos , Fósforo/química , Solo
17.
Vet Res Forum ; 3(3): 213-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-25610572

RESUMO

The present study was conducted on efficiency of utilization of dietary energy for milk production in lactating crossbred cattle. 18 lactating crossbred cattle of early to mid-lactation, approximate body weight (375.39±23.43 kg), milk yield, parity and stage of lactation were divided into three groups of six animals each and were fed 0, 50 and 100% diammonium phosphate (DAP) in the mineral mixture of concentrates for 120 days. The chaffed mixed roughage (berseem + wheat straw) and concentrate mixture was fed to supply about nearly 18:82 concentrate to roughage ratio on dry matter basis. Tap water was available to the animals twice daily. A metabolism trial of seven days was conducted at the end of experiment to study digestibility of organic nutrients and balances of energy. DAP did not affect the nutrient intake, body weight changes, digestibility of Dry matter (DM), Crude protein (CP), Ether extract (EE), Crude fiber (CF), Nitrogen free extract (NFE) and daily milk yield. It was concluded that the at 46.07 Mcal Gross energy intake level the losses in feces, urine, methane and heat production was 45.82%, 5.40%, 4.31% and 33.01%, respectively, and net energy retention for milk production was 11.43%. The gross efficiency of conversion of metabolic energy ME for milk production was 35.69% and the net efficiency of conversion of ME for milk production was 39.56%.

18.
Indian J Microbiol ; 50(4): 425-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22282610

RESUMO

Two plant growth promoting rhizobacteria--Sinorhizobium meliloti RMP1 and Pseudomonas aeruginosa GRC(2) were studied for integrated nutrient management to obtain improved yield of Brassica juncea. Low concentrations of urea and diammonium phosphate (DAP) stimulated the growth of both S. meliloti RMP1 and P. aeruginosa GRC(2). 1 M of urea and 0.35 M of DAP was found lethal for RMP1, while 1.3 M and 0.37 M concentrations of urea and DAP proved to be toxic for GRC(2). Lc(50) was observed as 0.49 M of urea and 0.15 M of DAP for RMP1, and 0.66 M urea and 0.18 M of DAP for GRC(2). Urea and DAP adaptive variants of RMP1 and GRC(2) was isolated. Adaptive bacterial variants had better growth rates at sub-lethal (Lc(50)) concentrations of urea and DAP as compared to non-adaptive variants. They also retained plant growth promoting attributes similar to non adaptive variants. GRC(2) and RMP1 did not affect the growth of each other and were chemotactically active for DAP, urea as well as root exudates of B. juncea. Both the isolates colonized well in the rhizosphere of B. juncea, as their populations were recorded ≈5 log(10) cfu g(-1) after 120 days. Interestingly, the colonization ability was found even better when both strains were co-inoculated, as their population was recorded in the range of ≈6 log(10) cfu g(-1) after 120 days. In field trials, application of RMP1 and GRC(2) resulted in significant increase in biomass and yield of B. juncea as compared to control. However, yield was better with application of half dose and full dose of recommended fertilizers. Interestingly, the biomass as well as yield improved further when both isolates were applied together along with half dose of recommended fertilizers.

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