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The leaf extract of Melia azedarach L. was obtained by soaking plant material in ethanol for one week and its toxic effect was assessed on the third instar larvae of khapra beetle (Trogoderma granarium Everts). Four concentrations of the extract (2, 4, 6 & 8 µL mL-1 acetone) were applied through contact method in Petri plates. Mortality was recorded after 12, 24 and 36 h. All the concentrations showed toxic effects against the larvae to variable extents. The highest mortality i.e. 72% was recorded at 8 µL mL-1 acetone concentration after 36 h incubation period. At the same concentration, the mortality was 61.67% and 48.34% after 24 and 12 h, respectively. Minimum mortality (23.33%) was observed at 2 µL mL -1 acetone concentration after 12 h. GC-MS analysis of ethanolic leaf extract of parthenium revealed the phytol as the predominant compound with 72.25% peak area. Other compounds were 2(4H)-benzofuranone, 5,6,7,7a-tetrahydro-4,4,7a-trimethyl-(6.30%), 1-(3,6,6-trimethyl-1,6,7,7a-tetrahydrocyclopenta[c]pyran-1-yl)ethanone (6.11%), methyl stearate (4.60%), (+/-)-phytone (4.38%), hexadecanoic acid, methyl ester (3.24%), and hexadecanoic acid, ethyl ester (3.12%). It is concluded that an 8 µL mL-1 acetone concentration of leaf extract of M. azedarach can kill up to 72% larvae of T. granarium in 36 hours. [ABSTRACT FROM AUTHOR]

Parthenium (Parthenium hysterophorus L.) is an exotic weed that has spread in different parts of Punjab, Khyber Pakhtunkhwa, and Kashmir to an alarming extent and is now threatening natural vegetation and ecosystems. In the present study, laboratory bioassays were carried out to evaluate the effect of heavy metal ion Cr(VI) on germination and root/shoot growth of parthenium. Five concentrations of the metal ion viz. 10, 20, 40, 80, and 160 ppm were used in the experiment. A gradual decline in germination and growth of seedlings was recorded with the increase in metallic ion concentration. Lower concentrations viz. 10, 20, and 40 ppm reduced seed germination by 11, 15, and 37% over control, respectively. Likewise, 10, 20, and 40 ppm metal solution reduced shoot length by 35, 67, and 93%, root length by 69, 93, and 95%, and plant dry biomass by 47, 69, and 97% over control, respectively. An 80 ppm solution of Cr(VI) completely arrested the germination. This study concludes that parthenium is highly susceptible to Cr(VI) stress, where an 80 ppm solution of these metallic ions can completely stop the germination of parthenium seeds. [ABSTRACT FROM AUTHOR]

Bergenia ciliata is a weed of hilly areas of Pakistan that generally grows in rock crevices. In the present study, flowers of this weed were collected from Murree, Pakistan. The dried flowers were extracted in methanol and subjected to GC-MS analysis that showed 7 compounds in it. The predominant compound was hexanedioic acid, bis(2-ethylhexyl) ester (48.88%) followed by γ-sitosterol (22.56%). Moderately occurring compound was cyclohexane, 1,3,5-triphenyl-(12.87%). The remaining compounds namely n-hexadecanoic acid (4.97%), pentadecanoic acid, 14-methyl-, methyl ester (3.77%), 9,12-octadecadienoic acid, methyl ester, (Z,Z)- (2.94%) and 9,12,15- octadecatrienoic acid, methyl ester, (Z,Z,Z)- (2.92%) were categorized as less abundant compounds. Literature survey indicated that these compounds possess antimicrobial, larvicidal, anti-inflammatory, anticancer and/or antidiabetic properties. [ABSTRACT FROM AUTHOR]

Hemp (Cannabis sativa L.), a medicinal plant of family Cannabaceae, growing wild in most of the rainfed areas of Punjab, Pakistan. In this study, phytochemical profile of methanolic extract of root was assessed through GC-MS analysis and various biologically active compounds were identified through literature survey. There were 14 compounds in the root extract. The most abundant compounds were ?-sitosterol (27.08%) and 9,12-octadecadienoic acid (Z,Z)-, methyl ester (24.09%) and hexadecanoic acid, methyl ester (21.81%). Other identified compounds were methyl stearate (5.51%), stigmasterol (5.12%), campesterol (4.19%), phenol, 2,2'-methylenebis[6-(1,1-dimethylethyl)-4-methyl-(2.52%), 11-octadecenoic acid, methyl ester (2.10%), squalene (1.89%), ß-amyrin (1.88%), eicosanoic acid, methyl ester (0.85%), tetracosanoic acid, methyl ester (0.88%), dronabinol (1.02%) and 2-methoxy-4-vinylphenol (0.96%). Most of the identified compounds possess one or more biological activities viz. antitumor, antifungal, antibacterial, antioxidant, anticancer, anti-inflammatory, antidiabetic, and analgesic. [ABSTRACT FROM AUTHOR]

Cirsium arvense (L.) Scop., commonly known as creeping thistle, is a weed of Asteraceae. This study was undertaken to explore various phytoconstituents present in flower of this weed. To achieve this goal, the dried flowers of this weed were soaked in methanol for one week and filtered. This methanolic extract was subjected to GC-MS analysis and 7 compounds were identified. These included olean-12-en-3-ol, acetate, (3β)- (63.87%), lanosta-8,24-dien-3-ol, acetate, (3β)- (12.12%), β-amyrin (6.19%), γ-sitosterol (6.09%), α-amyrin (5.24%), stigmasterol (3.29%) and carbonic acid, 2-ethylhexyl heptadecyl ester (3.16%). Literature survey showed that these compounds possess antiinflamatory, antimicrobial, antidiabetic, antioxidant and/or anticancer activities. [ABSTRACT FROM AUTHOR]

The fungus Aspergillus versicolor is generally found on food products and produces sterigmatocystin, a carcinogenic and hepatotoxic mycotoxin. This study reports the usefulness of polar and non-polar fractions of methanolic extract of hemp (Cannabis sativa L.) leaves against A. versicolor. Dried leaves of hemp were soaked in methanol for two weeks. The material was filtered and the methanol was evaporated on a rotary evaporator. Thereafter, water was added to the residues and the aqueous mixture was successively partitioned with n-hexane, chloroform, ethyl acetate and n-butanol. Different concentrations of each fraction were prepared which ranged from 1.562 to 200 mg mL-1. Antifungal activity was carried out in malt extract broth medium. In general, all the concentrations of the four organic solvent fractions significantly controlled the growth of A. versicolor. There were 71-100%, 59-100%, 65-100% and 69-100% decline in the biomass of A. versicolor due to nhexane, chloroform, ethyl acetate and n-butanol fractions, respectively. It is concluded that different fractions of leaf extract of C. sativa have remarkable potential in controlling growth of A. versicolor. [ABSTRACT FROM AUTHOR]

Antifungal potential of extracts of different parts of lambs quarters weed (Chenopodium album L.) against a plant pathogenic fungus Alternaria alternate assessed through laboratory bioassays. Different parts of the weed were soaked in methanol for two weeks to get the extracts. The solvent was evaporated under reduced pressure and different concentrations of the extracts of each plant part (1 to 5%) were prepared in malt extract broth. Leaf, root and fruit extracts exhibited pronounced antifungal activity resulting in 23-95%, 29-96% and 9-94% suppression in biomass of A. alternata. The effect of stem extract was insignificant. This study concluded that all parts of C. album except stem contain potent antifungal constituents to control A. alternata. [ABSTRACT FROM AUTHOR]

Charcoal rot disease caused by Macrophomina phaseolina (Tassi) Goid. is a highly destructive disease of mash bean [Vigna mungo (L.) Hepper] that causes significant yield losses annually. In this study, leaf dry biomass of Senna occidentalis [1, 2 and 3% (w/w of leaf biomass/soil)] and a biological control agent Penicillium oxalicum Currie and Thom were examined in a pot trial for their potential to improve growth of mash bean under biotic stress of M. phaseolina. M. phaseolina inoculation alone reduced shoot and root dry biomass by 19% and 67%, respectively. Soil amendments variably increased both shoot and root growth under biotic stress of M. phaseolina. There was 33-43% and 25-75%; 29% and 150%; and 38-43% and 34-125% increase in shoot and root biomass of mash bean due to different doses of S. occidentalis, P. oxalicum, and S. occidentalis + P. oxalicum, respectively, over positive control. Soil amendment with 3% leaf dry biomass of S. occidentalis combined with P. oxalicum significantly improved plant biomass as compared to rest of the treatments. This study concludes that soil amendment with 3% leaves of S. occidentalis either alone or in combination with P. oxalicum can be used for better crop growth of mash bean in M. phaseolina contaminated soil. [ABSTRACT FROM AUTHOR]

Macrophomina phaseolina (Tassi) Goid is a destructive fungal phytopathogen causing diseases in hundreds of plant species. No registered fungicide is available sofar to control this pathogen. This study was carried out to explore the antifungal activity of methanolic extracts of different parts of Eclipta alba (L.) Hassk, a weed of family Asteraceae, against M. phaseolina. Different concentrations (0, 1, 2, 3, 4 and 5%) of methanolic extracts of leaf, stem, root and inflorescence of this weed were evaluated against the target fungal pathogen using malt extract broth as growth medium. In general, extracts of all the plant parts exhibited variable antifungal activity. There was a linear and inverse relationship between fungal biomass and extract concentrations. Leaf and stem extracts showed the best antifungal activities resulting in up to 64% and 61% decrease in biomass of M. phaseolina, respectively. Methanolic extracts of root and inflorescence were proved comparatively less effective than extracts of other plant parts and reduced fungal biomass up to 32% and 19%, respectively. [ABSTRACT FROM AUTHOR]

Macrophomina phaseolina is the cause of charcoal rot in green gram [Vigna radiata (L.) Wilczek] and black gram [Vigna mungo (L.) Hepper]. A pot experiment was carried out in March 2013 to study the effect of soil amendment with a biological control agent Trichoderma harzianum and dry biomass of a brassicaceous weed Sisymbrium irio on charcoal rot disease of green gram. The present experiment was a continuation of that study and carried out in the same pots in September 2013 to study the effect of the soil amendments on crop growth of black gram. In general, number of leaves, and various root and shoot growth parameters were significantly decreased due to M. phaseolina inoculation. Application of 1, 2 and 3% dry biomass of S. irio or T. harzianum separately failed to alleviate biotic stress of M. phaseolina. However, combined application of 1% dry biomass of S. irio and T. harzianum significantly increased number of leaves by 23% over positive control inoculated only with M. phaseolina. Various parameters of root and shoot growth were also higher in this treatment as compared to other soil amendment treatments. [ABSTRACT FROM AUTHOR]

Extracts of three medicinal plants namely ginger (Zingiber officinale Roscoe), onion (Allium cepa L.) and garlic (Allium sativum L.) were assessed for their herbicidal activity against noxious parthenium weed (Parthenium hysterophorus L.). Aqueous as well as n-hexane extracts of the three test plant species effectively declined germination and early seedling growth of the weed. However, herbicidal potential of the extracts varied with the plant species and the extracting solvent. Herbicidal activity of aqueous extracts of garlic and onion was more pronounced than aqueous extract of ginger. The highest suppressive ability was exhibited by extracts of garlic where 10% and 15% concentrations completely inhibited germination, and root and shoot growth of parthenium. Similarly, n-hexane extract of ginger was found highly effective resulting in complete suppression of germination and seedling growth of parthenium. This study concludes that aqueous extracts of garlic and n-hexane extract of ginger are highly effective for management of parthenium weed. [ABSTRACT FROM AUTHOR]

Parthenium (Parthenium hysterophorus L.) belonging to family Asteraceae is an aggressive weed that threatens the natural ecosystem in many parts of the world. The present study was carried out to investigate the herbicidal potential of culture filtrates of six species of Aspergillus namely A. fumigatus, A. terreus, A. niger, A. flavus, A. parasiticus and A. spelunceus against parthenium weed in eco-friendly way. Original culture filtrates of A. fumigatus and A. niger considerably decreased parthenium seed germination by 22% and 28%, respectively. Likewise, culture filtrates of A. flavus and A. parasiticus significantly reduced shoot length by 70% and 48%, respectively. Root growth was highly susceptible to fungal culture filtrates exposure. Culture filtrates of all the Aspergillus spp. with the exception of A. spelunceus significantly reduced seedling root length by 43-92% over control. Culture filtrates of A. flavus and A. parasiticus exhibited the best herbicidal activity against shoot and root growth of parthenium. [ABSTRACT FROM AUTHOR]

A field study was conducted to evaluate the effect of nitrogen (N) rate (recommended and half dose) and farmyard manure (FYM) on weed competition in rice (Oryza saliva) var. Super Basmati. Four frequently occurring weeds viz., Echinochloa colonum, Cyperus rotundus, Marsilea minuta and Paspalum paspaloides were grown in rice in a 1:1 ratio of weed and rice plants. The highest vegetative growth and grain yield in weed free control plots was observed in FYM followed by full N and half N dose of fertilizers, respectively. Maximum losses in plant biomass and grain yield due to weed competition were recorded in FYM. Percentage losses in half and full dose of N due to different weeds were close to one another. Mixed weeds in all the three types of amendments generally were more damaging as compared to either of the four weed species. Weed biomass was generally greater in FYM and full N dose as compared to half N dose. [ABSTRACT FROM AUTHOR]

Present study was designed to evaluate the herbicidal activity of metabolites of four Drechslera species viz. D. australiensis, D. hawaiiensis, D. biseptata and D. holmii (prepared in malt extract broth) against some problematic weeds of wheat namely Rumex dentatus, Phalaris minor and Avena fatua in 2009. Metabolites of Drechslera spp. were employed in 100% (original) and 50% concentrations. These metabolites wrought appreciable reduction in the germination of test weed's seeds by 3-72%. Original metabolites of all the fungal species significantly reduced shoot length and biomass by 39-72% and 30-70%, respectively. Metabolites of D. australiensis D. hawaiiensis and D. biseptata showed pronounced phytotoxic activity against all tested weeds, D. holmii appeared to be least effective. Root growth was more susceptible to metabolites than shoot growth. The metabolites of Drechslera spp. reduced 56-97% and 27-92% in root and shoot biomass, respectively. The present study concludes that metabolites of all the tested Drechslera spp. contain phytotoxic constituents that can be used as benign method of weed control alternative to synthetic chemical herbicides for management of some weeds of wheat. Further studies regarding the isolation of effective ingredients are in progress. [ABSTRACT FROM AUTHOR]