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Grady H. Zuiderveen, Eric P. Burkhart, and Joshua D. Lambert

antimicrobial, anticancer, and immunostimulatory properties ( Predny and Chamberlain, 2005 ). The medicinal properties of goldenseal are widely attributed to three major isoquinoline alkaloids ( Supplemental Fig. 1A ): berberine, hydrastine, and canadine ( Abidi

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Arlette S. Cuomo, Steven E. Newman, Hassan H. Nassar, and Ronald J. Harkrader

There are many naturally occurring substances that have the potential to be adapted to modern pest control chemistry. Azadirachtin, an insect growth regulator, is one such naturally occurring compound that has been widely accepted in insect pest management. Quartenary benzophenanthridine alkaloids (QBAs) are known to be effective in the control of crop-damaging fungal diseases. QBAs can be isolated from plants in the Papaveraceae. Extracts of Macleaya cordata, a species rich in QBAs, were formulated for drench application to Cucumis sativa `White Wonder' seedlings. The seedlings were grown in a peat-lite medium using 10-cm plastic pots and inoculated with Rhizoctonia solani. Test formulations were prepared with and without QBAs and applied at 75, 150, and 300 ppm QBAs as a 100 ml/pot drench. The QBA formulations that provided effective control of Rhizoctonia solani lost 20% or fewer seedlings compared to the formulation without QBA, which lost more than 60% of the seedlings. Treated plants were evaluated confirming Rhizoctonia solani infection.

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Steven E. Newman, Michael J. Roll, and Ronald J. Harkrader

There are many naturally occurring substances that have the potential to be adapted to modern pest control chemistry. Azadirachtin, an insect growth regulator, is one such naturally occurring compound that has been widely accepted in insect pest management. Quartenary benzophenanthridine alkaloids (QBAs) are known to be effective in the control of crop damaging fungal diseases. QBAs can be isolated from plants in the Papaveraceae. Extracts of Macleaya cordata, a species rich in QBAs, were formulated at 150 mg·L–1 QBA for spray application to greenhouse roses infected with Sphaerotheca pannosa var. rosae (powdery mildew). The QBA formulation was applied at 10-day intervals. Copper sulfate pentahydrate (Phyton27), piperalin (Pipron), and fenarimol (Rubigan) were also applied to mildew infected plants within the same greenhouse at their respective label rates for comparison. One day after treatment, the mildew infection was reduced 50% by QBA, whereas fenarimol, copper sulfate pentahydrate, and piperalin reduced the infection 50%, 75%, and 80%, respectively. Nine days after application, the mildew infection of QBA treated plants was less than 5% of the leaflet surface area. QBAs have the potential to be developed as a biorational fungicide for greenhouse use with both fungicidal and fungistatic activity.

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Michael J. Roll, Steven E. Newman, and Ronald J. Harkrader

A formulation of quaternary benzophenathridine alkaloids (QBA) was combined with piperalin as a tank mix. The QBA was applied at 150 mg/L and piperalin, at the labeled rate, was applied as a spray application to greenhouse roses infected with Sphaerotheca pannosa var. rosae (powdery mildew). Copper sulfate pentahydrate and fenarimol were also applied to mildew-infected plants within the same greenhouse at their respective label rates for comparison. Initial infection for the QBA/piperalin combination spray was 45% of the leaflet surface area, 3 days after application the infection was reduced to 10%, 6 days after application infection was reduced to 5%, and 14 days after application the infection remained at 5%. Initial infection for a QBA application without piperalin was 25% of the leaflet surface area. Three days after application, the infection was reduced to 15%; 6 days after application the infection remained at 15%; and 14 days after application, the infection was reduced to 10%. The data reveals that the QBA/piperalin combination gives a short-term as well as a long-term fungicidal and fungistatic activity.

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Paul W. Bosland, Danise Coon, and Peter H. Cooke

. Karayatsubusa Plant Cell Physiol. 21 839 853 Suzuki, T. Iwai, K.Y. 1984 Constituents of red pepper spices: Chemistry, biochemistry, pharmacology and food science of the pungent principles of Capsicum species, p. 227–299. In: A. Brossi (ed.). The alkaloids

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Paongpetch Phimchan, Suchila Techawongstien, Saksit Chanthai, and Paul W. Bosland

unique alkaloid restricted to Capsicum species ( Suzuki and Iwai, 1984 ). There is increased use of the capsaicinoids in pharmacy products, sprays for riot control, self-defense, and the pesticide industries ( Shur, 2002 ). Capsaicinoid accumulation is

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Brad Geary, Jared Benson, Steven Wood, James Logan, Ben Brulotte, Alan Chambers, Jeff Maughan, and Mikel Stevens

Endophytic fungi that are classified into the genus Neotyphodium have developed into a very unique niche. Their specific host plants are the fescues and ryegrasses. Through fungal biosynthesis of secondary metabolites, the host plant receives several benefits. These benefits include resistance to insects such as aphids, chinch bug, and argentine stem weevil, increased drought tolerance, and increased competiveness. These secondary metabolites comprise four groups of alkaloids. The alkaloids are loline, peramine, Lolitrem B, and ergovaline. The quantitative alkaloid profile is unique for each isolate. The characterization of these endophytes is necessary for identification of specific isolates. We report the characterization of ten endophytic strains Lp1, Lp2, Lp3, Lm4, Lm5, Fp6, Fp7 Fp8, Fp9, Fp10. The characterization of each isolate includes: morphology, sporulation, growth rates, microsatellite fingerprint, and alkaloid profile. The isolated colonies bear resemblance to raised brain-like structures and are yellow to tan in color. Growth rates range between 0.1 and 0.25 mm/day. No colonies produced any form of sporulation. Fp6 was found to have the highest loline concentration of any isolate. AFLP analysis was performed on the isolates to test for relatedness. Distinct clades were formed and grouped by host. The main groups were those isolated from Lolium or Festuca varieties. Isolates Fp8 and Fp9 were most related to each other, and have also been found to be doubly infected. The double infection is described to be Phialophora-like, due to the presence of thin highly branched hyphae when observed under light microscopy with aniline blue staining.

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Enaksha R. Wickremesinhe and Richard N. Arteca

Fast growing callus was derived from Cephalotaxus harringtonia stem explants placed on MS basal salt medium with B-5 vitamins, 3% sucrose, 1 μM kinetin and 4.5 μM 2,4-D. Callus placed on basal medium with 10 μM kinetin and 0.45 μM 2,4-D turned green and organogenesis was observed upon subculture onto basal medium without hormones. Shoots were excised and placed on 1/2 strength MS salts and 10% sucrose for further shoot development. During the process of organogenesis, we also observed the differentiation of roots. Rapidly growing root cultures were established by culturing them under a 24 hour light regime of 35 μM/m2/s. Two grams of root tip explants cultured on B-5 medium with 2% sucrose were capable of producing an average of 24 grams of roots within 11 days. A 20-fold increase in fresh weight was achieved within 3 weeks when 15 grams of these roots were cultured in a 3 liter air-sparged bioreactor. C. harringtonia contains a number of alkaloids that exhibit cytotoxicity and are being evaluated as chemotherapeutic agents. We are currently in the process of establishing growth characteristics for these roots and assaying roots for the presence of these alkaloids. All cultures were grown under a 12 hour light regime unless otherwise stated.

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Enaksha R. Wickremesinhe and Richard N. Arteca

Cephalotaxus harringtonia plants produce alkaloid compounds possessing antitumor properties, the major one being homoharringtonine. The purpose of this study was to produce roots from callus cultures developed earlier. Fast growing callus cultures were placed on MS basal salt medium with B-5 vitamins, 2% sucrose, 10 μM kinetin, 0.45 μM 2,4-D and 0.2% Gelrite. Upon subculture onto basal medium without hormones, we observed organogenesis of both shoots and roots. Roots were excised and established on basal medium without hormones. By subculturing two 2-inch root tips containing numerous visible laterals in liquid medium we were able to harvest 30 g of roots/250 ml flask after 3 weeks and 50 g/250 ml flask after 6 weeks. A 20-fold increase in fresh weight was achieved within 3 weeks when 15 grams of roots were initially seeded into a 3 liter air-sparged bioreactor. However, most of these roots appeared to be fleshy/swollen while root cultures established from half inch root tips grew slower but were normal in appearance. We arc currently in the process of establishing growth characteristics for these roots and assaying roots for the presence of these alkaloids.

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Paul D. Curtis, Elizabeth D. Rowland, Meena M. Harribal, Gwen B. Curtis, J. Alan Renwick, Mathew D. Martin-Rehrmann, and George L. Good

Many plants have mechanisms of physical or chemical resistance that protect them from herbivores in their environment. The ornamental plant Pachysandra terminalis Sieb. and Zucc is highly unpalatable to voles, but the nature of this resistance is not fully understood. Extracts of P. terminalis were prepared to determine the extent to which chemical constituents could account for its avoidance by voles. A bioassay in which samples were mixed with applesauce showed that ethanolic extracts were highly deterrent to captive prairie voles (Microtus ochrogaster Wagner, 1842). Bioassay-guided fractionation of ethanol extracts showed that antifeedant activity was present in both polar and non-polar fractions. Further separation of each fraction by open column chromatography and high pressure liquid chromatography revealed that combinations of compounds were responsible for the deterrent activity. Preliminary ultraviolet and mass spectroscopic analyses indicated that steroidal alkaloids that are characteristic of this plant are likely to be involved.