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Biotic and abiotic stress factors drastically limit plant growth and productivity through changing the physiological, biochemical, and cellular processes. In this study, 100 mM of lead (Pb) was used as an abiotic stress source, while Fusarium graminearum represented a biotic one on wheat plant. Compared to the control, Pb treatment and F. graminearum inoculation led to remarkable reductions in the wheat seedlings leaf area that reached 21 %, and 12.5 %, respectively. Moreover, the current results showed an enhanced activity of Phenylalanine ammonia lyase (PAL) that reached 173 % in the stressed wheat grains and seedlings, decreased mineral contents in N-3, P+3, K+, and Ca+2 in the shoot of wheat seedlings by 25, 42, 23 and 44 %; respectively, substantial increase (79 %) in the total soluble carbohydrates (TSC) and a highly significant reduction (28 %) in the total soluble proteins (TSP), compared with the non-treated control plants. On the other hand, wheat seed priming with weed extracts [i.e., Portulaca oleracea L. (purslane) and Beta vulgaris L. (chard)], or chemical solutions; mainly Calcium (Ca+2) and Salicylic acid (SA) applied exogenously, resulted in a noteworthy increase in the leaf area, compared with the stress treatments. Furthermore, seed priming ameliorated the toxic effects induced by Pb and F. graminearum treatments on the photosynthetic pigments; where it significantly increased the pigments content, while the chlorophyll (Chl) a/b ratio was reduced. Furthermore, priming treatments significantly increased the mineral contents (i.e., N, P, K, and Ca) and counteracted the imposed effects of stress treatments on TSC and TSP. The differential display polymerase chain reaction (DD-PCR) technique was performed to identify the variations in gene expression between the different treatments of wheat plants at three intervals of 7, 14, and 21 d old. This study aimed to investigate the use of plant extracts as potentially effective and environmentally safe green bio-control agents to control the infection of wheat plant by F. graminearum, ameliorate the biotic and abiotic stresses, and compete with the currently used deleterious chemical fungicides in the wheat farms.

The contact toxicity of the crude ethanolic extract of leaves of three weeds species, Chromolaena odorata Linn. (Siam weed), Euphorbia heterophylla Linn. (Milk weed) and Tithonia diversifolia (Hemsl.) A,Gray, (Tree marigold) on Dinoderus minutus were investigated. Three concentrations of 2.5%, 5% and 7.5% and an increased concentration of 15%, 20% and 25% were prepared upon dilution with ethanol. Each experimental setup consists of petri dishes (9cm diameter by 2cm height), lined with a 9cm diameter filter paper (Whatman No.1) and four replicates maintained for each concentration in a completely randomized design (CRD). 1.0ml of the different concentrations of the ethanolic crude extract were spread on the filter paper in the petri dish and the control groups included a positive (+) control setup treated with the ethanol solvent alone and a negative (-) control setup without any treatment. The filter paper was allowed to air dry for 20minutes to evaporate the solvent and thereafter, ten active unsexed adults D. minutus were introduced into the petri dishes. The petri dishes were perforated and covered with muslin cloth to aid aeration and eliminate death by suffocation. The percentage mortality was recorded at 24hours interval for 96 hours and the percentage mortality calculated. The result showed low mortality using the treatment concentrations of 2.5%, 5.0% and 7.5%. The highest mean mortality of 45.00±2.89 was recorded at 25% treatment concentration in Euphorbia heterophylla, followed by Tithonia diversifolia and Chromolaena odorata with mean mortality of 37.50±8.54 and 20.00±4.08 respectively at same 25% treatment concentration while the lowest was observed in the negative (-) and positive (+) control at 2.50±2.50 and 7.50±2.50 respectively at 96hours exposure time. The application 25% E. heterophylla, and T. diversifolia can be used as an alternative to synthetic insecticide in the management of D. minutus and can be incorporated into the IPM component of the insect. [ABSTRACT FROM AUTHOR]

The allelopathic impact of 23 perennial weed species on oilseed radish by petri dish and soil bioassays was studied. Weed extracts were prepared at concentrations of 0.25, 0.5, 1.0, 2.0, 4.0, 8.0 and 16.0%. The influence of the weed extract on germination and seedling growth of oilseed radish was analyzed according to several germination indexes. The "speed of germination", "coefficient of the velocity of germination" and the resulting levels of allelopathic potential in terms of seed germination (APG) were used to assess the allelopathic effect of the researched weed species. The application of indicators allowed determining the specific features of the influence of extracts of perennial weeds on the duration of the germination period, the effects of germination delay and the general prolongation of the period of formation of similar seeds with typification on classification groups. Conducted daily surveys for the calculation of these indices allowed to obtain a graphical interpretation of the reaction of the seeds of the test object to the extract of each weed species. This allowed identifying species of weeds for which the use of oilseed radish in the system of its biological control will be effective.

Root rot and head blight caused by soil-borne fungi are prevalent diseases endanger the global food security. The purpose of this study is to provide insight into the interaction of Fusarium graminearum with two weed extracts, concentrating on growth rate, physiological responses, molecular changes in wheat seedlings and yield parameters. In a pot experiment, wheat grains pre-soaked for 12 h either in distilled water or 25% aqueous weed extracts (purslane or chard) were germinated either in free or F. graminearum pre-inoculated sandy soil. The results revealed that F. graminearum inoculation resulted in reduced growth rate and chlorophyll content in wheat seedlings. However, following the fungal invasion, carotenoids, stress markers (EL, MDA, C = O, OH˙ and H2O2), non-enzymatic antioxidants (ascorbate and flavonoids), osmoregulators (GB, proline and free amino acids), antioxidant enzymes activity (CAT, POX, SOD and PPO) and the expression of some stress-induced genes (CAT, GR and PR4) were substantially increased. Nevertheless, priming of wheat grains with purslane or chard extracts resulted in enhanced growth rate, balanced chlorophyll content, decreased stress symptoms, restoration of the normal level of osmoregulators and antioxidant enzymes activity, as well as down-regulation of stress-induced genes in F. graminearum-infected wheat seedlings, besides improving yield characteristics. However, PR2 gene expression was not affected by either fungal infection or weed priming. In conclusion, natural weed extracts as supplement to chemical antifungals, can be safely employed to increase the growth rate and reconfigure the pathophysiological status of wheat seedlings by reducing the detrimental effects of F. graminearum infection. [ABSTRACT FROM AUTHOR]

The allelopathic impact of 23 perennial weed species on oilseed radish by petri dish and soil bioassays was studied. Weed extracts were prepared at concentrations of 0.25, 0.5, 1.0, 2.0, 4.0, 8.0 and 16.0%. The influence of the weed extract on germination and seedling growth of oilseed radish was analyzed according to several germination indexes. The "speed of germination", "coefficient of the velocity of germination" and the resulting levels of allelopathic potential in terms of seed germination (APG) were used to assess the allelopathic effect of the researched weed species. The application of indicators allowed determining the specific features of the influence of extracts of perennial weeds on the duration of the germination period, the effects of germination delay and the general prolongation of the period of formation of similar seeds with typification on classification groups. Conducted daily surveys for the calculation of these indices allowed to obtain a graphical interpretation of the reaction of the seeds of the test object to the extract of each weed species. This allowed identifying species of weeds for which the use of oilseed radish in the system of its biological control will be effective. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum, a fungal plant pathogen, causes severe wilting and heavy losses in cotton. Present research was planned to appraise the weed extracts of Parthenium hysterophorus, Chenopodium album, Canada thistle and Phalaris minor against F. oxysporum. Morphological identification of F. oxysporum was done by observing white cottony mycelium with dark-purple undersurface on growth media and oval to ellipsoid/kidney shaped oval tapering and three septate spores. Molecular characterization was done by amplifying internal transcribed spacer region using the ITS universal primers, ITS1 and ITS4. The weed extract with concentrations of 5%, 10%, 15% and 20% were applied by using food poison techniques under complete randomized design. Data was taken 3, 5 and 7 days after inoculation of F. oxysporum on potato dextrose agar (PDA). P. hysterophorus showed maximum antifungal response (97%) against F. oxysporum whereas other treatments effectively inhibited the pathogen growth on PDA media. Tebuconazole, a fungicide, was used as positive control. Trichoderma harzianum showed 98% inhibition of F. oxysporum on PDA. Consortium of Trichoderma harzianum + weed extracts was applied in infected roots of cotton grown in pots under complete randomized design. No disease was observed in treatment P. hysterophorus + T. harzianum whereas maximum disease was calculated (50%) in other treatments as compared to control (100%).

The molluscicidal and antifeedant activity of three weeds extracts namely primpernel (Anagallis arvensis L.) (Primulaceae), nightshade (Solanum nigrum L.) (Solanaceae) and nutsedge (Cyperus longus L.) (Cyperaceae) were evaluated against the adult stage of Monacha obstructa (Pfeiffer, 1842) under laboratory conditions. Three methods of bioassay were used i.e. bait, residual film (contact) and antifeeding techniques. The results indicated that chloroform and hexane extracts of primpernel appeared highly toxic when applied as baits on M. obstructa adults while nutsedge was found to be lower toxicity based on LC50 values. Also, chloroform extract of nightshade and hexane extract of primpernel were the most potent with contact whereas nutsedge was the least effective. On the other hand, of either chloroform or hexane extract primpernel tended to be more effective as antifeedant compound than nightshade. In contrast, nutsedge chloroform extract revealed no action as a feeding deterrent whereas the same hexane extract was effective based on SC50 levels. Moreover, fifteen compounds were identified by GC/MS analysis in the chloroform extract of primpernel. Palmatic acid methyl ester (fatty acid) was the dominant compound representing 25.8% followed by aromadendrene (sesquiterpene) forming 15.2% and 2 – tertbutyl - 4- isopropyl – 5- methylphenol (phenolic compound) having 13.9%. In addition to the presence of two steroids, two dicarboxylic acids and only one ketone compound was identified. Finally, the salt of carbamic acid (ammonium carbamate) and the ester of phosphoric acid (tributyl phosphate) were also detected. This study reveals that chemical compounds present in chloroform extract of primpernel has effective source as a molluscicide extracted of plant origin and has potential beneficial control against M. obstructa snails. [ABSTRACT FROM AUTHOR]

Buckwheat (Fagopyrum tataricum) is an important but underexploited crop with high nutritional value. Rhizoctonia root rot caused by Rhizoctonia solani is a destructive disease in buckwheat and leads to yield loss. Screening of four weeds extracts from Ricinus communis, Datura metel, Tridax procumbens, and Solanum nigrum was conducted and antifungal activity determined against root rot fungus, Rhizoctonia solani. Poison food technique (in vitro antifungal assay) was used to test the efficacy and inhibition of fungal growth was recorded. Among all the plant extracts, Solanum nigrum ethanol extract showed the highest fungitoxicity (88%) at 500 ppm followed by Tridax procumbens and Datura metel (85 and 80%, respectively). Ricinus communis ethanol extract gave moderate fungitoxicity (65%). Aqueous extract of Solanum nigrum (one of the most potent among the weed extracts) was also evaluated in pot experiment for inhibition of disease incidence in buckwheat plants. Revival effect on buckwheat roots grown in Rhizoctonia infected pots was observed. The results hold promise for developing biological, eco-friendly, and non-hazardous antifungal products from common weeds. [ABSTRACT FROM AUTHOR]

This is the first investigation to demonstrate the use of biochemical contents present within Cyperus rotundus, Eleusin indica, Euphorbia hirta, Melastoma malabathricum, Clidemia hirta and Pachyrhizus erosus extracts for the reduction of silver ion to silver nanoparticles (AgNPs) form. In addition, the antibacterial capability of the synthesized AgNPs and plant extracts alone against a rare bacterium, Chromobacterium haemolyticum (C. haemolyticum), was examined. Moreover, ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX) and inductively coupled plasma atomic emission spectroscopy (ICPOES) of the synthesized AgNPs were characterized. The smallest AgNPs can be produced when Cyperus rotundus extracts were utilized. In addition, this study has found that the synthesis efficiencies using all plant extracts are in the range of 72% to 91% with the highest percentage achieved when Eleusin indica extract was employed. All synthesized AgNPs have antibacterial capability against all examined bacteria depending on their size and bacteria types. Interestingly, Melastoma malabathricum and Clidemia hirta extracts have demonstrated an antibacterial ability against C. haemolyticum. [ABSTRACT FROM AUTHOR]

This is the first investigation to demonstrate the use of biochemical contents present within Cyperus rotundus, Eleusin indica, Euphorbia hirta, Melastoma malabathricum, Clidemia hirta and Pachyrhizus erosus extracts for the reduction of silver ion to silver nanoparticles (AgNPs) form. In addition, the antibacterial capability of the synthesized AgNPs and plant extracts alone against a rare bacterium, Chromobacterium haemolyticum (C. haemolyticum), was examined. Moreover, ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX) and inductively coupled plasma atomic emission spectroscopy (ICPOES) of the synthesized AgNPs were characterized. The smallest AgNPs can be produced when Cyperus rotundus extracts were utilized. In addition, this study has found that the synthesis efficiencies using all plant extracts are in the range of 72% to 91% with the highest percentage achieved when Eleusin indica extract was employed. All synthesized AgNPs have antibacterial capability against all examined bacteria depending on their size and bacteria types. Interestingly, Melastoma malabathricum and Clidemia hirta extracts have demonstrated an antibacterial ability against C. haemolyticum.

Fusarium oxysporum , a fungal plant pathogen, causes severe wilting and heavy losses in cotton. Present research was planned to appraise the weed extracts of Parthenium hysterophorus , Chenopodium album , Canada thistle and Phalaris minor against F. oxysporum. Morphological identification of F. oxysporum was done by observing white cottony mycelium with dark-purple undersurface on growth media and oval to ellipsoid/kidney shaped oval tapering and three septate spores. Molecular characterization was done by amplifying internal transcribed spacer region using the ITS universal primers, ITS1 and ITS4. The weed extract with concentrations of 5%, 10%, 15% and 20% were applied by using food poison techniques under complete randomized design. Data was taken 3, 5 and 7 days after inoculation of F. oxysporum on potato dextrose agar (PDA). P. hysterophorus showed maximum antifungal response (97%) against F. oxysporum whereas other treatments effectively inhibited the pathogen growth on PDA media. Tebuconazole, a fungicide, was used as positive control. Trichoderma harzianum showed 98% inhibition of F. oxysporum on PDA. Consortium of Trichoderma harzianum + weed extracts was applied in infected roots of cotton grown in pots under complete randomized design. No disease was observed in treatment P. hysterophorus + T. harzianum whereas maximum disease was calculated (50%) in other treatments as compared to control (100%). [ABSTRACT FROM AUTHOR]

This is the first investigation to demonstrate the use of biochemical contents present within Cyperus rotundus , Eleusin indica , Euphorbia hirta , Melastoma malabathricum , Clidemia hirta and Pachyrhizus erosus extracts for the reduction of silver ion to silver nanoparticles (AgNPs) form. In addition, the antibacterial capability of the synthesized AgNPs and plant extracts alone against a rare bacterium, Chromobacterium haemolyticum ( C. haemolyticum ), was examined. Moreover, ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX) and inductively coupled plasma atomic emission spectroscopy (ICPOES) of the synthesized AgNPs were characterized. The smallest AgNPs can be produced when Cyperus rotundus extracts were utilized. In addition, this study has found that the synthesis efficiencies using all plant extracts are in the range of 72% to 91% with the highest percentage achieved when Eleusin indica extract was employed. All synthesized AgNPs have antibacterial capability against all examined bacteria depending on their size and bacteria types. Interestingly, Melastoma malabathricum and Clidemia hirta extracts have demonstrated an antibacterial ability against C. haemolyticum ., Competing Interests: The authors declare no conflict of interest.