Yield, carbon stock, and price dynamics of agroforestry tree species in district Mardan, Khyber Pakhtunkhwa, Pakistan.

A socio-economic study was conducted in district Mardan of the Khyber Pakhtunkhwa (KP) province of Pakistan to get a comprehensive knowledge of the agroforestry tree species grown on the farmlands, their yield, and carbon stock. For yield and carbon stock estimation, data were collected from 59 sample plots by measuring the diameter, height, volume, and biomass of selected agroforestry tree species through D-tape and Haga altimeter. A total of 59 sample plots were inventoried using 2.5 percent sampling intensity. Each sample plot has an area of 0.5 ha, where each tree with a Diameter at Breast Height (DBH) ≥ 5 cm was inventoried. The calculated amount of volume of each tree species was then converted to biomass by multiplying it by the density of wood and the Biomass Expansion Factor (BEF). Total yield and C stock for the selected agroforestry tree species were 11535.2 metric tons and 2102.2 metric tons, respectively. Populus euroamericana is classified as the main tree with 28% growing stock prior to Morus alba by 21%, while Melia azedarach, Eucalyptus camaldulensis, Dalbergia sissoo, Acacia nilotica, Salix tetrasperma, and Bombax ceiba consist of 15%, 12%, 8%, 6%,7% and 3% growing stock respectively. Among the species found in different sampling plots the yield of Populus euroamericana was found to be 4747.5 metric tons and it was followed by the species Morus alba found at 2027.3 metric tons. Similarly, the volume for Melia azedarach, Eucalyptus camaldulensis, Dalbergia sissoo, Salix spp, Boombox ceiba, and Acacia nilotica was 1532.2 tons,1503 ton,745.7,203.5ton, 555.4ton and 220.5ton, respectively. The carbon stock for Populus euroamericana was calculated as 777.8 ton/ha, while for Eucalyptus camaldulensis, Melia azedarach, Morus alba, Dalbergia sissoo, Acacia nilotica, Salix species, and Bombax ceiba it was calculated as 312.3ton/ha, 272.1ton/ha, 363ton/ha, 245.1ton/ha, 51.4ton/ha, 27.3ton/ha and 53.2ton/ha, respectively. The questionnaire survey conducted for price dynamics showed that the majority of respondents purchase timber from the market for construction. But they use farm trees with low-quality city construction. They dislike using local timber in the conventional building as timber from farm trees is liable to insect attack. Rs. 50,000-100000, (33.33%) of daily sales was concluded from 50% of the trader while (16.7%) of the traders have their sales between Rs.150,000-200,000. Therefore, it is concluded by the authors that both provincial and federal government should promote agroforestry in Pakistan through different incentives because it has the potential to cope with dilemma of deforestation of natural forests and improve the livelihood of local peoples. It is strongly recommended that special projects just like the Ten Billion Tree Afforestation Project (T-BTTP) should be launched for agroforestry plantation and promotion in the country to sustain the ecological harmony and uplift the socio-economic condition of the peoples of Pakistan.

Environmental sustainability assessment of softwood and hardwood seedlings production in forest nurseries: A case study from Pakistan.

This article describes the environmental impacts of producing a single seedling in forest nurseries of selected districts (i.e., Haripur, Abbottabad, and Mansehra) of Hazara Division of Khyber Pakhtunkhwa, Pakistan using the life cycle assessment (LCA) approach. This study was based on the cradle-to-gate approach which begins with the pre-nursery stage and progresses toward the main nursery before transplanting seedlings into the plantation site. Data or life cycle inventory (LCI) of seedling production were collected through questionnaire surveys and personal meetings with forest nurseries managers and workers regarding consumption of different inputs such as electricity, diesel, fertilizers, herbicides, and polyethylene bags, organic manure, and water consumption. The SimaPro software version 8.5 and the CML2000 v2.05 environmental model was applied to perform life cycle impact assessment (LCIA) for a single seedling production in forest nurseries in the study area. In line with the objectives of the study, primary data regarding inputs and outputs of the nurseries were collected from 35 nurseries in the study area by using a random questionnaire method. In addition, secondary data were taken from online databases such as Eco-invent v.3.2 CORRIM and peer-reviewed published literature. For this study, a functional unit of a single seedling was considered. Production weighted average data were modeled in the latest environmental modeling software i.e., SimaPro v.8.5 for ten US-EPA most wanted environmental impacts, such as global warming potential (GWP), abiotic depletion (AD), eutrophication potential (EP), acidification potential (AP), freshwater aquatic eco-toxicity (FAE), marine water eco-toxicity (MWE), terrestrial eco-toxicity (TE), ozone layer depletion (OLD), photochemical oxidation (PO), and human toxicity (HT). The results showed that the highest environmental impact posed by a single seedling was marine aquatic eco-toxicity (11.31360 kg 1,4-DB eq), followed by global warming potential (0.02945 kg CO2 eq) and (0.01227 kg 1,4-DB eq) human toxicity. The primary reason for these environmental burdens was the use of synthetic fertilizers in forest nurseries and the consumption of fossil fuels in nursery mechanization and transportation activities. The total cumulative energy demand for a single seedling was (0.800 MJ) with more than 90% contribution from fossil fuel energy resources such as petrol and diesel. It is therefore highly recommended to use renewable energy resources and organic fertilizers instead of chemical fertilizers in forest nurseries to avoid and minimize greenhouse gas emissions (GHS) and other toxic emissions in the study area.

Economic valuation of selected ecosystem services in Islamabad Capital Territory (ICT), Pakistan.

Payment for ecosystem services (PES) is a mechanism where a consumer is able and ready to pay for the protection of the precise ecosystem service and there must be a provider such as local societies receiving an economic resource, who in return, must have the ability to maintain that ecosystem service. Economic valuation provides basis for payment for ecosystem services. Therefore, objective of this study was to evaluate tourism and carbon stock services of the Islamabad Capital Territory (ICT), Pakistan. Two forest zones (Chirpine and Scrub) of Islamabad capital territory (ICT) were selected for estimation of carbon stock and their carbon credits and carbon worth, a questionnaire-based survey was conducted for tourism as a payment for ecosystem services. The method for carbon stock assessment was systematic sampling for Chirpine forest whereas random sampling was done for scrub forest. The size of sampling plot was 17.84 m radius, and a total of 93 plots (49 Scrub zone and 44 Chirpine zone) was taken in the study area. The carbon stock of both zones (Chirpine and Scrub zone) is 22556.75 ton/ha (Chirpine 20105.79, Scrub 2450.96) and total carbon dioxide sequestered by both zone is 82557.72 ton/ha (Chirpine 73587.2, Scrub 8970.52), total carbon credits of both zone is 302160.87 (Chirpine 269328.97, Scrub 32831.9) and the carbon worth of both Chirpine and scrub zone is 4532418.92 $ (Chirpine 4039937.09$, Scrub 492481.83$). Similarly, from tourism point of view, in Shakar Parian, 94% tourists were agreed for PES whereas 6% were disagreed for the PES (the 6% tourist were disagreed to contribute for PES, 40% were agreed for Rs.5 contribution and 54% for Rs.10.). moreover, in Lake view Park, 97% tourists were agreed and 3% are disagreed (In Lake View Park 5% tourists were disagreed for the PES contribution whereas 32% were agreed for Rs.5 and 63% were for Rs.10). In Damen e Koh, around 87% tourist were agreed and 13% were disagreed, (24% were agreed for the contribution of Rs.5 and 63% tourists were agreed for the contribution of Rs.10). In Marghazar Zoo, 93% tourists were agreed (22% were agreed for contribution of Rs.5 and 71% tourist were agreed for contribution of Rs.10) and 7% are disagreed for PES whereas 7% tourists were not agreed for contribution. PES may implement to compensate forest and parks manager to ensure better management of the forests and parks. Due to prime location and scenic beauty of the ICT, it has huge potential for implementation of PES mechanism for sustainable forest management and conservation. Therefore, it is recommended that Capital Development Authority (CDA) Islamabad should devise a plan for implementation of PES in forests and parks of ICT for its sustainable management of recreational and forest resources.

Report: Incidence of malaria in the population of Korangi creek area, Karachi, Pakistan.

Parasites lives on host organism with some or complete metabolic dependence on it, while the haemoparasites inhabit and nourished from blood cells of the host. The current investigation evaluated to raise awareness of blood parasite (Plasmodium spp.) infection in Korangi creek, Karachi, population and to know as to which Plasmodium species was most prevalent. One year data was collected from different hospitals and laboratories of the Korangi creek area, blood slides were prepared under the microscope. Four hundred and eighty one infected slides with Plasmodium were observed amongst them 396 (82.32 percent) had P. vivax and 85 (17.67 percent) had P. falciparum infection. The rate of infection did not vary with gender but had a signification association with age. Highest incidence was recorded in age group 16-40 years for both P. vivax and P. falciparum followed by age group 1-15 years in P. vivax and age group 41-60 years for P. falciparum. It was suggested that protective measures are required to overcome disease that include covering arms and legs, using repellents mosquito nets along with proper dispensing and appropriate treatment.

Nanoscale, tunable, and highly sensitive biosensor utilizing hyperbolic metamaterials in the near-infrared range.

A plethora of research in recent years has been reported on biosensing in the surface plasmon resonant systems. However, very little research has reported a tunable and highly sensitive biosensor in a nanoscale platform. In this regard, we propose a nanoscale hyperbolic metamaterial (HMM)-based prism coupled waveguide sensor (PCWS) in the near-infrared range. The HMM layer makes up one of the constituents of the PCWS-comprised of a periodically arranged assembly of silver nanostrips. The structure is numerically simulated by the finite difference time domain method. It is demonstrated that the sensitivity of the reflected light can be tuned through the refractive index (RI) of the solution. Moreover, the effects of alteration of constituents of PCWS on the sensitivity have been analyzed. Results show that the sensitivity of PCWS can be harnessed by altering the thickness, slant angle of HMM layer, volume fraction (f) of metal in the HMM layer, and the incidence angle of light. For this purpose, the structure is numerically simulated by the finite difference time domain method. In the optimum design of the proposed sensor, the maximum value of sensitivity is achieved as high as S=3450 nm/refractive index unit with θ=10° and ϕ=10° and a metamaterial thickness of 250 nm. Moreover, the structure has a nanoscale footprint of 600 nm×400 nm×200 nm.

Laparoscopic Common Bile Duct Exploration for Retrieval of Impacted Dormia Basket following Endoscopic Retrograde Cholangiopancreatography with Mechanical Failure: Case Report with Literature Review.

Dormia baskets are commonly used during endoscopic retrograde cholangiopancreatography (ERCP). One complication is basket retention, through impaction with a gallstone or wire fracture. We describe a case where the external handle of the basket snapped causing retained basket plus large gallstone impacted in the common bile duct (CBD). Following laparoscopic cholecystectomy, laparoscopic CBD exploration allowed direct stone fragmentation under vision with the choledochoscope. Fragments were removed using a choledochoscopic basket and Fogarty catheter, and the basket was withdrawn. Literature search identified 114 cases of retained baskets with management including shockwave lithotripsy (27%), papillary balloon dilatation (22%), open CBD exploration (11%), and one laparoscopic case.

Characterization of group B coxsackieviruses isolated from non-polio acute flaccid paralysis patients in Pakistan: vital assessment before polio eradication.

Pakistan is at the verge of polio eradication but isolation of non-polio enteroviruses (NPEVs) from acute flaccid paralysis (AFP) cases may result in serious or even fatal outcome. Many enteroviruses share similar symptoms and epidemiology as is the case with poliovirus and coxsackievirus (CV). The present study was designed to genetically characterize coxsackievirus B (CV-B) serotypes isolated from non-polio acute flaccid paralytic children, as well as to understand their probable role in paralysis. A total of 63 (20·1%) out of 313 stool samples during 2013 were found positive for NPEVs in rhabdomyosarcoma cells. Only 24 (38·0%) NPEVs were typed as CV-B by microneutralization assay and were further characterized by sequencing of the viral protein 1 (VP1) gene. Molecular phylogenetic analyses classified the study strains into six coxsackievirus B serotypes (coxsackievirus B1 to B6) with their respective prototype strains with evidence of epidemiological linkage and distinct clusters. Moreover, four major differences were found within the amino acid sequences of BC-loop in VP1 of CV-B strains. In conclusion, this study presented the molecular evolutionary genetic overview and distinct phylogenetic pattern of CV-B isolates from AFP cases in Pakistan, and explored the possible link between CV-B infections and AFP cases. Furthermore, our data reveal that these viruses might contribute to the incidence of paralysis in population and there is need of time to establish an enterovirus surveillance system for better understanding of epidemiological and virological characteristics of NPEV infections associated with AFP cases in the country.

Size, density and cholesterol load of HDL predict microangiopathy, coronary artery disease and ß-cell function in men with T2DM.

The role of high-density lipoprotein cholesterol (HDL-C) as modifiable risk factor for cardiovascular (CV) disease is increasingly debated, notwithstanding the finding that small-dense and dysfunctional HDL are associated with the metabolic syndrome and T2DM. In order to better clarify the epidemiological risk related to HDL of different size/density, without resorting to direct measures, it would seem appropriate to adjust HDL-C to the level of its main apolipoprotein (apoA-I), thereby providing an [HDL-C/apoA-I] ratio. The latter allows not only to estimate an average size for HDLs, but also to derive indices on particle number, cholesterol load, and density. So far, the potential usefulness of this ratio in diabetes is barely addressed. To this end, we sorted 488 male patients with T2DM according to [HDL-C/apoA-I] quartiles (Q), to determine how the ratio relates to cardiometabolic risk, ß-cell function, glycaemic control, and micro- and macrovascular complications. Five lipid parameters were derived from the combined determination of HDL-C and apoA-I, namely HDL size; particle number; cholesterol load/particle; apoA-I/particle; and particle density. An unfavorable cardiometabolic profile characterized patients from QI and QII, in which HDLs were pro-atherogenic, denser and apoA-I-depleted. By contrast, QIII patients had an [HDL-C/apoA-I] ratio close to that of non-diabetic controls. QIV patients had better than average HDL size and composition, and in those patients whose [HDL-C/apoA-I] ratio was above normal, a more favorable phenotype was observed regarding lifestyle, anthropometry, metabolic comorbidities, insulin sensitivity, MetS score/severity, glycaemic control, and target-organ damage pregalence in small or large vessels. In conclusion, [HDL-C/apoA-I] and the resulting indices of HDL composition and functionality predict macrovascular risk and ß-cell function decline, as well as overall microangiopathic risk, suggesting that this ratio could serve both in cardiometabolic assessment and as biomarker of vascular complications.

Report - Most common body parts infected with scabies in children and its control.

Scabies a skin disease caused by mite Sarcoptes scabiei is common in Pakistan and spreads mostly where there is frequent skin to skin contact. In the present study children belonging to four age groups 0-3 years, 4-6 years, 7-9 years and 10-12 years attending Baqai Institute and Hospital Gadap from June-September 2013 were examined. The association between scabies of different human parts and age for boys was significant (p<0.01), while for girls it was highly significant (p<0.001). The most frequent body parts infected with scabies lesions were hands, head and feet. Oral ivermectin was effective antiscabietic for children as it was easy to administer and had good patient acceptability.

The normal-weight type 2 diabetes phenotype revisited.

BACKGROUND: Type 2 diabetes (T2DM) is associated with obesity, insulin resistance and the metabolic syndrome (MetS). In non-diabetic populations, features of metabolic obesity (MO) are observed in a minority of normal-weight (NW) subjects. The cardiometabolic status of metabolically obese but normal-weight (MONW) individuals has not yet been phenotyped in T2DM. PATIENTS AND METHODS: Prevalence and features of MONW were analyzed in 1244 T2DM patients, in whom MONW was identified as a BMI <25.0 and a MetS score ≥3/5. Among NW (n=262; 21%), those without MetS (n=152; NW-MetS[-]) were compared to NW-MetS[+] (n=110; i.e. 42% of NW and 9% of all T2DM). RESULTS: There were no differences between groups in age; gender; diabetes duration; smoking; BP; and LDL-C. NW-MetS[+] had higher BMI; waist; fat mass; visceral fat; liver steatosis and HbA1c, and lower insulin sensitivity. Non-right-handedness was twice-higher (18%) in NW-MetS[-]. NW-MetS[+] had higher apoB100 and triglycerides, and lower HDL-C and LDL size. Macroangiopathy was present in 39% of NW-MetS[+] vs. 22% of NW-MetS[-], as coronary (23% vs. 14%) or peripheral artery disease (14% vs. 5%) and TIA/stroke (15% vs. 7%). Microangiopathy was present in 54% of NW-MetS[+] vs. 32% of NW-MetS[-], as retinopathy (25% vs. 13%); neuropathy (29% vs. 18%); and albuminuria (39% vs. 20%). CONCLUSIONS: MONW among T2DM represents a significant minority (about 1 in 10). Their cardiometabolic phenotype deserves attention due to multiple comorbidities, including a twice-higher prevalence of micro-/macrovascular damage in patients wrongly perceived at lower risk due to normal BMI. Unexpectedly, non-right-handedness was over-represented among metabolically healthy patients.

Assessment of groundwater quality in the coastal area of Sindh province, Pakistan.

Groundwater is a highly important resource, especially for human consumption and agricultural production. This study offers an assessment of groundwater quality in the coastal areas of Sindh province in Pakistan. Fifty-six samples of groundwater were taken at depths ranging from 30 to 50 m. Bacteriological and physico-chemical analyses were performed using the Standard Methods for the Examination of Water and Wastewater. These were supplemented with expert interviews and observations to identify the usage of water and potential sources of pollution. The quality of the groundwater was found to be unsuitable for human consumption, despite being used for this purpose. The concentrations of sulfate and phosphate were well within the tolerance limits. Most critical were the high levels of organic and fecal pollution followed by turbidity and salinity. Metal concentrations (As, Ca, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn) were also determined, and Ni and Pb strongly exceeded health standards. The study stresses the need for significant improvements of the irrigation, sanitation, and sewage infrastructure.

Epidemiology and phylogenetic analysis of VP7 and VP4 genes of rotaviruses circulating in Rawalpindi, Pakistan during 2010.

Human group A rotaviruses (RVAs) possess a large genetic diversity and new RVA strains and G/P genotype combinations are been identified frequently. Only a few studies reporting the distribution and co-circulation of RVA G and P genotypes are available for Pakistan. This hospital based study showed a RVA prevalence rate of 23.8%, which is similar to RVA detection rates estimated in other Eastern Mediterranean countries. During 2010, the following RVA strains were found to co-circulate: G1P[8] and G2P[4] (both 24.3%), G1P[6] (12.1%), G9P[8] (10.8%), G9P[6] (5.4%), G12P[6] (6.7%), G6P[1] (2.7%) and mixed infections (6.7%). Sequence analyses of selected G1, G2, G9 and G12 RVA strains revealed a close evolutionary relationship with typical human RVA strains. Sequence identities among the Pakistani VP7 RVA genes encoding G1, G2, G9 and G12 ranged between 91.5-98.7%, 99.6-98.9%, 97.7-99.5% and 99.2-99.9%, respectively. Analysis of the VP4 genes revealed co-prevalence of distinct lineages of the P[8] genotype. P[6] and P[4] showed a close relationship with typical human RVA strains detected in several Asian countries. The two G6P[1] RVA strains were closely related to typical bovine RVA strains, suggesting one or multiple interspecies transmission events. Our data provide important baseline data on the burden of RVA disease and genotype distribution in Rawalpindi, Pakistan, which is important with respect to vaccine introduction in national immunization programs.

Enhanced decomposition of reactive blue 19 dye in ultrasound assisted electrochemical reactor.

Textile industry effluents contain reactive dyes that may harm our receiving waters. A typical reactive blue (RB) 19 dye is frequently detected in significant concentrations in textile industry effluents. Such dyes have generally shown resistance to decomposition and tend to persist in the environment for long periods and multiply the impacts to water and environment. Therefore, the present investigation focused on high-rate decomposition of a typical reactive dye RB 19 under various ultrasound and electrochemical process conditions. The decomposition of un-hydrolyzed and hydrolyzed forms of reactive blue (RB) 19 dye by ultrasound assisted electrochemical process was investigated using various parameters including dye concentration, pH, ultrasonic frequency and reaction time. Reaction kinetics, organic carbon and mechanism for dye decomposition were determined using UV-Visible spectrophotometry, TOC (total organic carbon) analysis and gas chromatography-mass spectrometry (GC-MS). Almost complete 90% color removal and a maximum of 56% TOC removal for 50 mg L(-1) dye concentration of un-hydrolyzed RB 19 dye was achieved at an ultrasonic frequency of 80 kHz, pH of 8 after 120 min. GC-MS analysis showed that a sonoelectrochemical treatment of un-hydrolyzed RB 19 dye for 30 min resulted in the formation of products e.g. acetic acid, benzoic acid etc. with the complete removal of dye. For hydrolyzed dye, a treatment of 10 min was enough and the results were comparable with 30 min treatment of un-hydrolyzed dye. Kinetics of ultrasound assisted electrolysis showed that the dye decomposition followed 1st order. The ultrasound assisted electrolysis for dye decomposition and hence decolorization proved to be more effective and the total energy consumption reduced to half as compared with simple electrolysis/sonochemical decomposition. Therefore, ultrasound assisted electrolysis was found to be more effective technique for dye decomposition of an otherwise environmentally persistent reactive dye.

Phenylacetic acid-producing Rhizoctonia solani represses the biosynthesis of nematicidal compounds in vitro and influences biocontrol of Meloidogyne incognita in tomato by Pseudomonas fluorescens strain CHA0 and its GM derivatives.

AIMS: The aim of the present investigation was to determine the influence of Rhizoctonia solani and its pathogenicity factor on the production of nematicidal agent(s) by Pseudomonas fluorescens strain CHA0 and its GM derivatives in vitro and nematode biocontrol potential by bacterial inoculants in tomato. METHODS AND RESULTS: One (Rs7) of the nine R. solani isolates from infected tomato roots inhibited seedling emergence and caused root rot in tomato. Thin layer chromatography revealed that culture filtrates of two isolates (Rs3 and Rs7) produced brown spots at Rf-values closely similar to synthetic phenylacetic acid (PAA), a phytotoxic factor. Filtrates from isolate Rs7, amended with the growth medium of P. fluorescens, markedly repressed nematicidal activity and PhlA'-'LacZ reporter gene expression of the bacteria in vitro. On the contrary, isolate Rs4 enhanced nematicidal potential of a 2,4-diacetylphloroglucinol overproducing mutant, CHA0/pME3424, of P. fluorescens strain CHA0 in vitro. Therefore, R. solani isolates Rs4 and Rs7 were tested more rigorously for their potential to influence biocontrol effectiveness of the bacterial agents. Methanol extract of the culture filtrates of PAA-producing isolate Rs7 resulting from medium amended with phenylalanine enhanced fungal repression of the production of nematicidal agents by bacteria, while amendments with zinc or molybdenum eliminated such fungal repression, thereby restoring bacterial potential to cause nematode mortality in vitro. A pot experiment was carried out, 3-week-old tomato seedlings were infested with R. solani isolates Rs4 or Rs7 and/or inoculated with Meloidogyne incognita, the root-knot nematode. The infested soil was treated with aqueous cell suspensions (10(8) CFU) of P. fluorescens strain CHA0 or its GM derivatives or left untreated (as a control). Observations taken 45 days after nematode inoculation revealed that, irrespective of the bacterial treatments, galling intensity per gram of fresh tomato roots was markedly higher in soil amended with isolate Rs4 than in Rs7-amended soils. Soil amendments with R. solani and the bacterial antagonists resulted in substantial reductions of the number of galls per gram of root. These results are contradictory to those obtained under in vitro conditions where culture filtrates of PAA-positive Rs7 repressed the production of nematicidal compounds. Plants grown in Rs7-amended soils, with or without bacterial inoculants, had lesser shoot and root weights than plants grown in nonamended or Rs4-amended soils. Moreover, amendments with Rs7 substantially retarded root growth and produced necrotic lesions that reduced the number of entry sites for invasion and subsequent infection by nematodes. Populations of P. fluorescens in the tomato rhizosphere were markedly higher in Rs7-amended soils. CONCLUSIONS: PAA-producing virulent R. solani drastically affects the potential of P. fluorescens to cause death of M. incognita juveniles in vitro and influences bacterial effectiveness to suppress nematodes in tomato roots. SIGNIFICANCE AND IMPACT OF THE STUDY: As most agricultural soils are infested with root-infecting fungi, including R. solani, it is likely that some PAA-producing isolates of the fungus may also be isolated from such soils. The inhibitory effect of PAA-producing R. solani on the biosynthesis of nematicidal agent(s) critical in biocontrol may reduce or even eliminate the effectiveness of fluorescent pseudomonads against root-knot nematodes, both in nursery beds and in field conditions. Introduction of bacterial inoculants, for the control of any plant pathogen, should be avoided in soils infested with PAA-producing R. solani. Alternatively, the agents could be applied together with an appropriate quantity of fungicide or chemicals such as zinc to create an environment more favourable for bacterial biocontrol action.

Differential impact of some Aspergillus species on Meloidogyne javanica biocontrol by Pseudomonas fluorescens strain CHA0.

AIMS: The aim was to determine the influence of some Aspergillus species on the production of nematicidal agent(s) in vitro and biocontrol of Meloidogyne javanica in tomato by Pseudomonas fluorescens strains CHA0 and CHA0/pME3424. METHODS AND RESULTS: Six species of Aspergillus, isolated from the rhizosphere of certain crops, produced a variety of secondary metabolites in vitro. Culture filtrate (CF) obtained from Ps. fluorescens strain CHA0 and its2,4-diacetylphloroglucinol overproducing mutant CHA0/pME3424 grown in King's B liquid medium caused significant mortality of M. javanica juveniles in vitro. Bacterial growth medium amended with CF of A. niger enhanced nematicidal and beta-galactosidase activities of fluorescent pseudomonads while A. quadrilineatus repressed such activities. Methanol or ethyl acetate extracts of the CF of A. niger markedly optimized bacterial efficacy to cause nematode deaths while hexane extract of the fungus had no influence on the nematicidal activity of the bacterial strains. A. niger applied alone or in conjunction with the bacterial inoculants inhibited root-knot nematode galling in tomato. On the other hand, A. quadrilineatus used alone or together with CHA0 did not inhibit nematode galling but when used in combination with strain CHA0/pME3424 did reduce galling intensity. CONCLUSIONS: Aspergillus niger enhances the production of nematicidal compounds by Ps. fluorescensin vitro and improves biocontrol potential of the bacterial inoculants in tomato while A. quadrilineatus reduces bacterial performance to suppress root-knot nematodes. SIGNIFICANCE AND IMPACT OF THE STUDY: Rhizosphere harbours a variety of micro-organisms including bacteria, fungi and viruses. Aspergillus species are ubiquitous in most agricultural soils and generally produce a variety of secondary metabolites. Such metabolites synthesized by Aspergillus species may influence the production of nematicidal agents and subsequent biocontrol performance of the bacterial inoculants against plant-parasitic nematodes. This fact needs to be taken into consideration when using biocontrol strains in an agriculture system.

Liquid culture carbon, nitrogen and inorganic phosphate source regulate nematicidal activity by fluorescent pseudomonads in vitro.

AIMS: The aim of the present investigation was to determine the influence of nutrients on the nematicidal activity by Pseudomonas aeruginosa strain IE-6S+ and Ps. fluorescens strain CHA0 in vitro. METHODS AND RESULTS: Culture filtrate of IE-6S+ and CHA0 obtained from chemically defined medium caused mortality of Meloidogyne javanica juveniles in vitro and that growth medium amended with various C, N or inorganic phosphate (Pi) sources markedly influenced nematicidal activity of the two bacteria. Glycerol (C source), propionate (fatty acid precursor) and L-lysine (N source) enhanced nematicidal activity while glucose (C), L-valine (N) and Pi substantially repressed nematicidal activity of the two bacteria. CONCLUSION: Liquid culture amendments with various C, N or Pi sources modulate the biosynthesis of nematicidal agents to a different extent in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Developing bacterial strains more responsive to certain environmental signals can be exploited for increased secondary metabolite production in pharmaceutical fermentations and offers new avenues to improve biocontrol.

Trichoderma harzianum enhances the production of nematicidal compounds in vitro and improves biocontrol of Meloidogyne javanica by Pseudomonas fluorescens in tomato.

AIMS: To determine the influence of soil-borne fungus Trichoderma harzianum on the biocontrol performance of Pseudomonas fluorescens strain CHA0 and its 2,4-diacetylphloroglucinol (DAPG) overproducing derivative CHA0/pME3424 against Meloidogyne javanica. METHODS AND RESULTS: Amendment of the culture filtrate (CF) or methanol extract of the CF of a T. harzianum strain Th6 to P. fluorescens growth medium enhanced the production of nematicidal compound(s) by bacterial inoculants in vitro. In addition, bacteria overwhelmingly expressed phl'-'lacZ reporter gene when the medium was amended with CF of T. harzianum. Pseudomonas fluorescens and T. harzianum applied together in unsterilized sandy loam soil caused greater reduction in nematode population densities in tomato roots. CONCLUSIONS: Trichoderma harzianum improves root-knot nematode biocontrol by the antagonistic rhizobacterium P. fluorescens both in vitro and under glasshouse conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The synergistic effect of T. harzianum on the production of nematicidal compound(s) critical in biocontrol may improve the efficacy of biocontrol bacteria against plant-parasitic nematodes. Considering the inconsistent performance of the biocontrol agents under field conditions, application of a mixture of compatible T. harzianum and P. fluorescens would more closely mimic the natural situation and might broaden the spectrum of biocontrol activity with enhanced efficacy and reliability of control.

Impact of biocontrol agents Pseudomonas fluorescens CHA0 and its genetically modified derivatives on the diversity of culturable fungi in the rhizosphere of mungbean.

AIMS: To assess whether Pseudomonas fluorescens strain CHA0 and its genetically modified derivatives, CHA0/pME3424 (antibiotic over-producer) and CHA89 (antibiotic-deficient) could have an impact on the fungal community structure and composition in the rhizosphere of mungbean. METHODS AND RESULTS: Under glasshouse conditions, mungbean was grown repeatedly in the same soil, which was inoculated with CHA0, CHA0/pME3424, CHA89 or was left untreated. Treatments were applied to soil at the start of each 36-day mungbean growth cycle, and their effects on the diversity of the rhizosphere populations of culturable fungi were assessed at the end of the first, second and third cycles. The effects of CHA0 and CHA0/pME3424 did differ from the controls while CHA89 did not. Whereas all major fungal species were frequently isolated from both bacterized and nonbacterized rhizospheres, certain fungal species were exclusively promoted or specifically suppressed from Pseudomonas-treated soils. In general, fungal diversity and equitability tended to decrease with time while species richness slightly increased. Whilst a total of 29 fungal species were isolated from the mungbean rhizosphere, only eight species colonized the root tissues. CONCLUSIONS: Soil inoculation with Ps. fluorescens CHA0 or CHA0/pME3424 altered fungal community structure in mungbean rhizosphere but strain CHA89 failed to produce such effect. SIGNIFICANCE AND IMPACT OF THE STUDY: Pseudomonas fluorescens-mediated alteration in the composition and structure of fungal communities might have acute or lasting effects on ecosystem functioning. Furthermore, the study provides useful data pertinent to characterization of the fate of genetically modified inoculants (e.g. antibiotic-overproducing Pseudomonas strains) released into the environment.

Sonochemical degradation of organophosphorus pesticide in dilute aqueous solutions.

Ultrasonic irradiation was found to accelerate the rate of hydrolysis of omethoate in aqueous solution over the pH range of 2-12. Process parameters studied include pH, steady-state temperature, concentration, and the type of gases. Greater than 96% hydrolysis was observed in 30 minutes through this process and the rate of destruction increased with the help of more soluble and low thermal inert gas. So with Krypton, omethoate was found to undergo rapid destruction as compared with Argon. In the presence of ultrasound, the observed first-order rate of hydrolysis of omethoate is found to be independent of pH. The formation of transient supercritical water (SCW) appears to be an important factor in the acceleration of chemical reactions in the presence of ultrasound. A detailed chemical reaction mechanism for omethoate destruction in water was formulated. Experimental results and theoretical kinetic mechanism demonstrated that the most of the omethoate undergo destruction inside the cavitating holes. A very less effect of temperature on the degradation of omethoate within a temperature range of 20-70 degrees C proves that a small quantity of omethoate undergoes secondary destruction in the bulk liquid.

Non-pathogenic Fusarium solani represses the biosynthesis of nematicidal compounds in vitro and reduces the biocontrol of Meloidogyne javanica by Pseudomonas fluorescens in tomato.

AIMS: The aim of the present investigation was to determine the influence of various Fusarium solani strains on the production of nematicidal agent(s) in vitro and biocontrol of Meloidogyne javanica in tomato by Pseudomonas fluorescens strains CHA0 and CHA0/pME3424. METHODS AND RESULTS: Culture filtrates (CF) of P. fluorescens strain CHA0 and its diacetylphloroglucinol-overproducing derivative CHA0/pME3424 caused substantial mortality of M. javanica juveniles in vitro. Bacterial growth medium amended with the growth medium of F. solani repressed the nematicidal activity of the bacteria. Methanol extract of F. solani CF resulting from Czapek's Dox liquid (CDL) medium without zinc amendment repressed the nematicidal activity of the bacteria while the CF obtained from CDL medium amended with zinc did not. Conidial suspension of F. solani strain Fs5 (repressor strain for the biosynthesis of nematicidal compounds in P. fluorescens) reduced biocontrol potential of the bacterial inoculants against M. javanica in tomato while strain Fs3 (non-repressor) did not. CONCLUSIONS: Fusarium solani strains with increased nematicidal activity repress the biosynthesis of nematicidal compounds by P. fluorescens strains in vitro and greatly alter its biocontrol efficacy against root-knot nematode under natural conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Fusarium solani strains are distributed worldwide and found in almost all the agricultural fields which suggest that some mycotoxin-producing strains will also be found in almost any soil sample taken. Besides the suppressive effect of these metabolite-producing strains on the production of nematicidal compound(s) critical in biocontrol, F. solani strains may also affect the performance of mycotoxin-sensitive biocontrol bacteria effective against plant-parasitic nematodes.