Weed Extracts Research Articles

Role of a Phytotonic-Dravya in the Induction of Resistance of Paddy to Bipolaris oryzae Infection

In order to trigger defense mechanisms in plants, abiotic or biotic factors can be used as inducers/elicitors. In the present study, Dravya (a sea weed extract) was evaluated for its compatibility with common synthetic fungicides like Bavistin and Dithane M-45. Dravya was found to be highly compatible with Dithane M-45, in which the incidence of Bipolaris oryzae and Alternaria padwickii was reduced to a greater extent in the paddy seed sample of Cv. IR-64, a popular variety for popped rice in South India. In parallel, seed germination and seedling vigour were also enhanced over control. Treated seedlings also indicated the enhanced peroxidase and phenylalanine ammonia-lyase activities upon challenge inoculation with Bipolaris oryzae. Challenged seedlings showed higher activity of enzymes on second and fourth day after inoculation. The suppression in disease incidence of the seedlings was also noticed in the growing plants indicated the promising effects of Dravya with Dithane M-45 under green house conditions.

The role of allelopathy in host-virus relations

Introduction The term allelopathy was introduced by Molish (1937) at the first time. Earlier it was considered as a type of interference among higher plants, where products of secondary metabolism inhibit (less promote) the development and physiological processes of neighbourhood plants (Rice 1984). The term allelopathy has been extended recently, including not only plant-plant, but also plant microorganism interactions. It is considered as a new alternative way for biological weed control (Duke et al. 2002, Dikic et al. 2003), in order to reduce environmental pollution (Nemeth Konda 2003). Plant viruses make up about 15-30% out of the whole plant diseases. Virus particles create extremely close biological units with the host cell. The biosynthesis of viruses is done by the organelles of the host cell. Therefore chemical protection against viruses is unsuccesful in vivo and causes the death of the host plant cell at the same time. In spite of this, some natural substances are known to inhibit the replication and cellto cell movement of viruses and to reduce virus concentration (Moraes et al. 1974, Baranwal and Verma 1997, Manickam and Rajappan 1998, Vivanco et al. 1999). The mode of action of natural substances is not yet known exactly, but it can be presumed, that these substances may modify special receptor places on the plant cell surface, therefore adhesion of virus particles can not be happened (Gaborjanyi and Tobias 1986). The aim of our investigations was to study the effect of allelopathic weed extracts on host-vims relations.

Jimson Weed Extract as a Protective Agent in Severe Organophosphate Toxicity

Jimson Weed Extract as a Protective Agent in Severe Organophosphate Toxicity

Jimson weed extract as a protective agent in severe organophosphate toxicity.

Treatment of patients following an organophosphate (OP) exposure can deplete a hospital's entire supply of atropine. Given the possibility of multiple severe exposures after a terrorist attack using OP nerve agents, there exists a need for either greater atropine stores or the development of alternative antidotes. Jimson weed (Datura stramonium) contains atropine and other anticholinergic compounds and is common and readily available. It is used recreationally for its central anticholinergic effects and is made easily into an extract by boiling the crushed seeds. The extract has rapid onset of effects and may be useful for treatment of OP poisoning. To determine whether pretreatment with an easily stored and prepared Datura seed extract (DSE) will increase survival following a severe OP poisoning. Datura stramonium seeds were collected, crushed, and then heated in water to make a 2-mg/mL atropine solution (100 seeds contain approximately 6 mg of atropine or 0.007 mg/seed). Male rats were randomized to pretreatment with either saline (n = 10) or 7.5 mg/kg DSE (n = 10) given as a single intraperitoneal injection 5 minutes prior to a subcutaneous injection of 25 mg/kg of dichlorvos. The endpoint was time to death recorded by a blinded observer. The Kaplan-Meier estimates of the 24-hour survival rate was 90% (95% CI = 56% to 100%) for the DSE-pretreated group and 10% (95% CI = 0% to 45%) for the control group. The log-rank test revealed a statistically significant longer survival for the Datura-treated animals (p = 0.0002). Median survival time was 22 minutes 30 seconds for the control group and greater than 24 hours for the DSE-pretreated group. Pretreatment with DSE significantly increases survival following severe dichlorvos exposure.

Alleviation of verticillium wilt in pepper ( Capsicum annuum L.) by using the organic amendment COA H of natural origin

Pepper seedlings cv. “Piquillo” were grown for 3 months in unamended medium with organic growing medium COA H (containing salicylic acid (SA), soluble ammonium salts and sea weed extract from Ascophyllum nodosum) inoculated or not inoculated with Verticillium dahliae Kleb. and in amended growing medium with COA H inoculated or not inoculated with V. dahliae. Seedling growth parameters, leaf content of relative water and chlorophyll, leaf gas exchange and resistance as well as total phenolics in stems were determined on days 0, 7, 21, 28 and 33 after inoculation with V. dahliae. SA in stems was measured on days 0, 21 and 33 and leaf nutrient content was analysed on day 33. Results indicate that the organic amendment COA H delayed senescence in Verticillium-inoculated seedlings. In fact, inoculated seedlings that received COA H always exhibited similar leaf resistance to water vapour as well as leaf content of chlorophyll, relative water and nutrients to their relative healthy controls. By contrast, the content of chlorophyll a and relative water in leaves from unamended seedlings significantly decreased on days 21 and 28, respectively, reaching values 30 and 20% lower than those found in the unamended healthy controls. Likewise, the content of chlorophyll b, potassium (K) and magnesium (Mg) in leaves from unamended seedlings inoculated with V. dahliae had declined 35, 40 and 50%, respectively, of the control values by day 33 after pathogen inoculation. On the other hand, while Verticillium-inoculated seedlings grown in amended medium with COA H maintained control photosynthetic rates for 21 days after inoculation, CO 2 exchange rates decreased from day 21 in unamended ones and the leaf resistance in these seedlings enhanced 50% 1 week after inoculation. In addition, Verticillium-inoculated seedlings supplied with COA H delayed the appearance of disease symptoms and their disease index on day 33 was about 40% lower than that measured in unamended pepper. The early accumulation of phenolics (from day 7 after inoculation) in pepper grown in amended medium with COA H could be involved in the greater disease resistance and/or tolerance exhibited by these seedlings.

Antifungal Activity from Water Extracts of Some Common Weeds

Antifungal Activity from Water Extracts of Some Common Weeds

Detection of cucumber mosaic cucumovirus in weed species: a cautionary report on nonspecific reactions in ELISA

The reliability of enzyme-linked immunosorbent assay (ELISA) to detect cucumber mosaic cucumovirus (CMV) coat protein (CP) in three weed species (Taraxacum officinale, Gnaphalium obtusifolium, and Conyza canadensis) was compared with other detection methods, including Western blot analysis and a bioassay. Analysis of extracts prepared from these species by double antibody sandwich (DAS) ELISA yielded high absorbance values (A4O5nm) that were indicative of CMV concentrations of purified CMV standards of greater than 50 mg/mL. However, results from an ELISA procedure designed such that no viral antigen should be detected suggested that the strong ELISA absorbance values were nonspecific reactions with material(s) in the weed extracts. These findings were substantiated when no CMV CP was detected by Western blot analysis or infectious CMV was detected in bioassays involving inoculation of extracts onto an indicator host (Cucurbita pepo ‘Crookneck’ (squash)). In both DAS ELISA and indirect ELISA procedures, the nonspecific reaction was shown to result from the interaction of weed extract and alkaline phosphatase-conjugated immunoglobulin (including anti-CMV and goat anti-rabbit). Addition of bovine serum albumin to the extraction buffer for DAS ELISA or to the extraction buffer and at each antibody step for indirect ELISA dramatically reduced the nonspecific reactions.

Effects of mold proteases on the biological activity of allergenic pollen extracts

Abstract Objective To determine the effect of mold extracts with high protease activity on the biological activity of allergenic tree, grass, and weed extracts, using in vivo and in vitro methods, in atopic dogs. Animals 15 dogs with history and clinical signs of atopy. All dogs had strong positive reactions (3+ or 4+) to 1 or more preselected allergens and negative reactions (0) to molds. Procedure Mold extracts and saline solution were coincubated separately with tree, grass, and weed pollen extracts at 4 C for 30 and 180 days. Skin end-point titration (30-day incubation) and ELISA inhibition (30- and 180- day incubations) tests were performed on all samples. The biological activity of pollen extracts coincubated with mold extracts was compared with that of pollen extracts coincubated with saline solution. Results In the skin end-point titration test, weed pollen extracts coincubated with a mixed mold extract lost a statistically significant amount of biological activity, compared with saline coincubated controls. In the ELISA inhibition test, grass and weed pollen extracts incubated with a mixed mold extract lost a significant amount of biological activity, compared with saline coincubated controls. A significant correlation in the measurement of biological activity was found between a loss of end-point dilution in the skin end-point titration test and a decrease in relative potency, as measured by the ELISA inhibition test for allergenic grass and weed extracts. Conclusion and Clinical Relevance Mold proteases can decrease the biological activity of certain grass and weed pollen extracts when coincubated in the same vial for 30 days. Separation of mold and pollen extracts, when preparing immunotherapy vaccines, may help prevent loss of pollen extract potency and increase the vaccine’s stability and efficacy. (Am J Vet Res 1996;57:1447-1452)

Fungicidal Activity of Some Common Weed Extracts Against Different Plant Pathogenic Fungi

AbstractAqueous extract effects of 64 weed species on growth and development of Alternaria solani Sorauer. Helminthosporium satirum King & Bakke and Rhizodonia solani Kuhn. plant pathogenic fungi were studied in vitro. Extracts varied in the strength and persistence of their antifungal effects against the three fungi species. Some stimulated, others inhibited or had no effect. Among all species tested, extracts of Chenopodium murale, Falearia vulgaris. Ranunculus asiaticus and Sisymbrium irio were the most toxic to A. solani. Anagallis arlensis. Atriptex leucoclada, Crepis aspera. Notobasis syriaca. R. asiatieus, Rumex crispu. S. irio. Sonehu.s oleraceous and Vieia narhonensis to H. satirum and R. asiatieus. S. oleraceous and Mercurialis annua to R. solani. However. R. asiatieus extract was the most effective and completely inhibited growth and sporulation of the three fungi species at all incubation periods.

474 Local nasal immunotherapy (LNIT) with aqueous weed extract is an effective therapy for weed induced rhinitis

474 Local nasal immunotherapy (LNIT) with aqueous weed extract is an effective therapy for weed induced rhinitis

Allelopathic Effect of Lantana (Lantana camara) and Siam Weed (Chromolaena odorata) on Selected Crops

Laboratory, greenhouse, and field studies were conducted to determine the allelopathic potential of lantana and Siam weed on the germination and growth of five crops. Emergence and dry weight of bioassay species were affected when lantana or Siam weed debris was present on the soil surface or incorporated into the soil. However, presence of Siam weed on the soil surface did not affect dry weight of rape. Emergence and dry weight of crops (except emergence of spinach) were not affected when crops were grown in soil samples collected from beneath field-grown lantana. Dry weight of Chinese cabbage and chilli was reduced when these crops were grown in Siam weed-contaminated soil. Germination of Chinese cabbage, chilli, and rape decreased progressively when exposed to increasing concentrations of aqueous lantana extract. However, the lantana extract at full strength (66.7 g L−1) did not reduce germination of spinach and cucumber seed. Siam weed extract, when applied at full strength to seed of spinach, Chinese cabbage, rape, and chilli, reduced germination by 10, 12, 21, and 19% of control, respectively. Full-strength extract of lantana and Siam weed decreased seedling length and fresh weight of all crops.

Bioassays of duck weed vegetation extracts

Bioassays against the fourth instar larvae of mosquito, Culex pipiens pipiens showed that the non polar part of the duck weed, Lemna minor extracts has a high insecticidal action. On the other hand, these extracts contained synomones of the duck weed which repelled the ovipositing females. By using concentrations equivalent to LC25, the survival resulting by the n. hexane was the least. The tolerance for the sublethal doses was associated with malformations in all stages. First instar larvae and recent pupae were more susceptible to the duck weed synomones than the other larval instars. The duck weed synomones repelled the ovipositing females of Piophila casei and have had an insecticidal effect on larvae and reduced resulting adults. When larvae of Spodoptera littoralis were subjected to sublethal doses of duck weed extract, malformations in the subsequent stages were found.

Inhibition of A nabaena cylindrica (Cyanophyceae) growth by extracts of water weeds, using the paper disc-agar method

We investigated for the growth inhibition effect on Anabaena cylindrica by four kinds of water weed extracts using paper disc method. Inhibitionon growth was observed in the acidic fraction, Aql and Ag1M in 4 kinds of water weeds. Floating-leaved plant, E. crassipes root extracts were larger than diameter of zone of inhibition leaf extracts.In case of N, officinale and O. stolonifera leaf extracts diatmeter of zone were larger than root extracts.P.orientalis, the zone of inhibition were observed larger in thhe Aql and AqlM than acidic fraction.The effect of antibiotic substances on the growth of A.cylindrica were observed diameters of zone of inhibition were 10mm for Streptomycin 50ppm, 13mm for Tetracycline 100ppm and 14mm for Penicillin G 500ppm.

Crude extracts of asteraceous weeds

Petrol and ethanolic extracts of six asteraceous weeds were added to artificial diets to screen for growth inhibition and mortality of the variegated cutworm,Peridroma saucia (Hbn). Petrol and ethanolic extracts ofArtemisia tridentata andChamomilla suaveolens and ethanolic extracts ofChrysothamnus nauseosus andCentaurea diffusa severely inhibited larval growth at five times the natural concentrations. The twoC. suaveolens extracts and the ethanol extract ofA. tridentata were active at the natural concentration (100%) and were further examined at 20, 40, 60, and 80% of this level. Inhibition of larval growth was directly related to concentration for each of the three extracts tested. EC50s (effective concentration to inhibit growth by 50% relative to controls) for the three extracts were 36-42% of the naturally occurring level in the plants. Nutritional indices were calculated for secondinstarP. saucia feeding on the activeA. tridentata EtOH extract and the petrol extract fromC. suaveolens. Addition of the activeA. tridentata EtOH or theC. suaveolens petrol extract to the diet resulted in significant reduction in the relative growth rate of larvae, although theA. tridentata extract was much more inhibitory. Dietary utilization was significantly lower for larvae fed theA. tridentata EtOH extract.

Evaluation of some weed extracts against field dodder on alfalfa (Medicago sativa)

Experiments were conducted to evaluate the effectiveness of some weed extracts against field dodderCuscuta campestris Yunck. on alfalfa (Medicago stiva L.) and to identify and quantify the phytotoxic agents of these extracts. All concentrations of aqueous extract of every weed showed significant effectiveness on dodder when compared to the untreated plant under lath house and field conditions. Control percentages of the (0.5 g) of Bermuda grass (Cynodon dactylon) and wall goosefoot (Chenopodium murale) ranged between 83 and 96, and the same concentration caused injury to alfalfa foliage up to 43% when applied in the field. Phytotoxic agents were identified as phenolic compounds such as chlorogenic, isochlorogenic,p-coumaric acids, and scopoletin. Their quantities varied with species; Bermuda grass had the highest content (32.2 μg/g dry weight) followed by Johnson grass (Sorghum halepense), well goosefoot, and tumble pigweed (Amaranthus albus). These results might aid in screening for effective alternate approaches for controlling dodder on alfalfa planted for seeds.

A new mast cell depleter, extracted from the sea week Geledium capillaceum [proceedings

Sea weed extract probably acts like compound 48/80 in releasing histamine and heparin from mast cells.

INTERFERENCE OF ALLELOCHEMICALS OF THREE WEED SPECIES IN SEED GERMINATION, SEEDLING GROWTH, UPTAKE OF PHOSPHORUS AND ZINC IN THREE VARIETIES OF PADDY

Effect of the extracts of three dominant weed species viz., Phalaris minor Retz., Chenopodium album L. and Polygonum hydropiper L. were examined on the seed germination, seedling growth and nutrient uptake (32p and 65Zn) in Swarna, Jaya and N-359 varieties of paddy (Oryza sativa L.). The maximum reduction in terms of seed germination, radicle and plumule length and total seedling dry weight was caused by P. hydropiper and in terms of radicle and plumule dry weight by C. album. Among the three different varieties irrespective of weed extracts, Swarna was resistant in seed germination, plumule length, radicle, plumule and total seedling dry weight and Jaya was only for radicle length, whereas N-359 was found susceptible in length and total seedling dry weight. The allelochemicals also interfered in gradual decrease in uptake of both 32P and 65Zn with increasing concentration of the chosen three weed extracts, both in root and shoot. Among the three varieties of paddy, Jaya was susceptible for 32P but resistant for 65Zn whereas N-359 was resistant for both the ions. Water soluble phenolics such as gallic, protocatechuic, p-hydroxybenzoic, caffeic and vanillic acids were identified from these extracts. The inhibition may be due to these phenolics and other unidentified secondary metabolites in weed extracts.
 
 Key words: Germination, nutrient uptake, paddy, phenolics, seedling growth, weed extracts.
 
 Ecoprint Vol.11(1) 2004.

Methanolic extracts ofthreeweeds as botanical fungicides to controlpeanut rust disease

Abstract. Yusnawan E, Inayati A. 2016. Methanolic extracts of three weeds as botanical fungicides to control peanut rust disease. Nusantara Bioscience 8: 117-122. Rust disease caused by Puccinia arachidis is one of the most important diseases on peanuts. Ageratum (Ageratum conyzoides L.), spiny amaranth (Amaranthus spinosus L.), and coco-grass (Cyperus rotundus L.) had the ability to inhibit plant pathogens. The aim of the research was to obtain the weed extracts effective to control peanut rust disease. The three weeds were ground to obtain fine particles, macerated in methanol for 18 h and evaporated the solvent using vacuum rotary evaporator. Methanolic crude extracts obtained from ageratum, coco-grass, and spiny amaranth at concentrations of 0.1%, 1.0%, 2.5%, and 5.0% were applied to the uredospores and peanut plants infected with the pathogen. Applications of 5% ageratum and 5% coco-grass extracts suppressed the spore germinations by 78 to 80% and 76 to 80%, respectively. Disease intensities on Kancil cultivar treated with 5% crude extract of ageratum were 18 to 22% and 29 to 31% after three and four times of extract applications. Disease intensities on untreated plants were 30 to 32% and 43 to 46%, whereas the chemical application suppressed the disease intensities up to 16 to 18% and 15 to 17% at the same time of observation. Preliminary phytochemical screenings showed that the methanolic extract of ageratum contained alkaloids, flavonoids, tannins, saponins, and terpenoids. Crude extract of 5% ageratum was effective to control rust disease on peanuts, therefore, could be used as an alternative control agent to suppress the disease.