Effect Of Volatile Substances Research Articles

Fumigant toxicity and behavioral alterations of six plant essential oils against the red fire ant (Solenopsis invicta Buren).

The red imported fire ant (RIFA), Solenopsis invicta Buren (Hymenoptera: Formicidae), is an invasive species that is considered to be among the 100 most dangerous species to human health and the environment. RIFA is currently controlled primarily by chemical insecticides. However, human health concerns and environmental problems require environment friendly, green insect pest control technology. In this study, the HS-SPME-GC/MS method was used to determine the volatile components of six essential oils, namely Illicium verum Burm, Blumea balsamifera (L.) DC., Citrus limon Burm, Acorus tatarinowii Schott, Mosla chinensis Maxim, and Cinnamomum cassia Presl, as well as their fumigation activity against RIFA. D-Limonene was identified as a core volatile in all six essential oils. The effects of volatile substances from essential oils on the fumigation activity and behavior of RIFA workers were studied by closed fumigation method. Except for C. limon essential oil, all other five plant essential oils exhibit excellent fumigation activity under the treatment of a concentration at 10 μL/ cm3 within 24 h. All plant essential oils are capable of causing the death of all red fire ants, while C. limon essential oil exhibited the lowest fumigation activity at 63.25%. Significant reductions in RIFA aggregation, aggressiveness, and gripping abilities were observed with all plant essential oils, and antenna sensilla appeared to bend or break. Moreover, after treating red ant fire ants with essential oil for 24 h, three protective enzyme activities were assessed. All six plant essential oils were shown to have enhanced enzyme activities for superoxide dismutase (SOD), glutathione S-transferase (GST), and catalase (CAT). It has been shown that plant essential oils have the capability of reducing the viability of red fire ants via receptor and behavioral factors, ultimately causing them to die off. As a conclusion, plant oils were demonstrated to be negatively affecting RIFA and providing a green and environmentally sustainable control method in this study.

A novel salt-tolerant strain Trichoderma atroviride HN082102.1 isolated from marine habitat alleviates salt stress and diminishes cucumber root rot caused by Fusarium oxysporum

BackgroundSalt stress threaten the growth of plants, and even aggravate plant disease. In this article, salt-tolerant Trichoderma strain was isolated, and its potential to alleviate salt stress and diminish cucumber root rot caused by Fusarium oxysporum was evaluated.ResultsTwenty-seven Trichoderma isolates were isolated from samples of sea muds and algae collected from the South Sea of China. Among these, the isolate HN082102.1 showed the most excellent salt tolerance and antagonistic activity against F. oxysporum causing root rot in cucumber and was identified as T. atroviride. Its antagonism ability may be due to mycoparasitism and inhibition effect of volatile substances. The application of Trichoderma mitigated the adverse effects of salt stress and promoted the growth of cucumber under 100 mM and 200 mM NaCl, especially for the root. When T. atroviride HN082102.1 was applied, root fresh weights increased by 92.55 and 84.86%, respectively, and root dry weights increased by 75.71 and 53.31%, respectively. Meanwhile, the application of HN082102.1 reduced the disease index of cucumber root rot by 63.64 and 71.01% under 100- and 0-mM saline conditions, respectively, indicating that this isolate could inhibit cucumber root rot under salt stress.ConclusionsThis is the first report of salt-tolerant T. atroviride isolated from marine habitat showing antagonistic activity to F. oxysporum, and the results provide evidence for the novel strain T. atroviride HN082102.1 in alleviating salt stress and diminishing cucumber root rot, indicating that T. atroviride strain HN082102.1 can be used as biological control agent in saline alkali land.

Effect of volatile substances from Streptomyces philanthi RM-1-138 on growth of Rhizoctonia solani on rice leaf

Volatile compounds generated from Streptomyces philanthi RM-1-138 grown on autoclaved wheat seeds for seven or 14 days suppressed the growth of four plant pathogenic fungi (Rhizoctonia solani PTRRC-9, Pyricularia grisea PTRRC-18, Bipolaris oryzae PTRRC-36 and Fusarium fujikuroi PTRRC-16). The inhibition was most pronounced on R. solani PTRRC-9 while the least inhibition was against F. fujikuroi PTRRC-16. The volatile compounds from 14 days old cultures exhibited a stronger inhibitory effect (52.85–100 %) on the four fungal strains than those from the 7 days old cultures (17.03–89.40 %). Identification of the volatile organic compounds produced by Streptomyces philanthi RM-1-138 using gas chromatography–mass spectrometry (GC–MS) revealed 17 and 36 compounds from the seven days old and 14 days old cultures, respectively. They could be chemically grouped into alcohols, alkenes, aromatic hydrocarbons, sulfides, ketones, ester and alkanes, some of which were known antimicrobial agents. Among them, the most abundant volatile component was 3,7-dimethylocta-1,6-dien-3-ol (l-linalool). Effect of the inoculum size and spore concentration of S. philanthi RM-1-138 prepared as a wheat seed inoculum on the suppression of R. solani PTRRC-9 was studied. Total inhibition of growth (100 %) was achieved using an inoculum size of at least 15 g l−1 and a spore concentration of 1 × 107 spore ml−1, respectively. Consistent (closed container) transfer of volatile substances from S. philanthi RM-1-138 to healthy tissues of rice leaves effectively reduced the incidence and/or the severity of sheath blight disease caused by mycelium or sclerotia. The cell wall of R. solani PTRRC-9 showed damage as observed by a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The results indicated that the volatile compounds from S. philanthi RM-1-138 could effectively control the rice sheath blight disease caused by R. solani PTRRC-9.

Phytotoxicity and Volatile Monoterpenes of Leaves from Artemisia capillaris and Artemisia iwayomogi Used as Korean Herbal Injin

Artemisia capillaris and Artemisia iwayomogi are weeds used as medicinal plants in Korea under the name Injin. I collected leaves of A. capillaris and A. iwayomogi, examined them for phytotoxic effects from volatile substances and determined the composition of monoterpenes in the leaves. The effects of volatile substances from each species on seed germination and radicle elongation in each of the two Artemisia species were assessed. The volatile substances of A. capillaris did not negatively affect the seed germination of A. capillaris, but they did inhibit radicle elongation. Rates of seed germination of A. iwayomogi decreased when the seeds were exposed to high concentration of A. capillaris volatile substances. The inhibition of seed germination and radicle elongation by volatile substances from both Artemisia species was stronger for A. iwayomogi than for A. capillaris. I identified the monoterpenoids from the leaves with a gas chromatograph-mass spectrometer (GC-MS). The main constituents of A. capillaris were acenaphthylene (37.91%), -pinene (12.08%), 4-carene (10.61%) and -curcumene (9.92%), while those of A. iwayomogi were germacrene- (32.15%), borneol (21.24%), camphor (20.45%) and trans-caryophyllene (7.75%).

Effect of volatile substances of Streptomycesplatensis F-1 on control of plant fungal diseases

Headspace volatile substances (VS) produced by Streptomyces platensis F-1 were preliminarily identified using GC–MS. The effects of VS released by S. platensis F-1 on the control of leaf blight/seedling blight of rice caused by Rhizoctonia solani, leaf blight of oilseed rape caused by Sclerotinia sclerotiorum and fruit rot of strawberry caused by Botrytis cinerea, as well as on the growth of these three pathogenic fungi, were investigated. Results showed that sixteen volatile compounds were tentatively identified in 1-week-old cultures of S. platensis F-1 grown on autoclaved wheat seeds. They could be chemically grouped into alcohols, esters, acids, alkanes, ketones and alkenes. The most abundant composition in volatiles of S. platensis F-1 is geosmin, an earthy-muddy–smelling compound. Two antifungal compounds, phenylethyl alcohol and (+)-epi-bicyclesesquiphellandrene, were detected in the volatile profile of S. platensis F-1. Consistent fumigation of healthy tissues of rice, oilseed rape and strawberry to VS of S. platensis effectively reduced the incidence and/or the severity of leaf blight/seedling blight of rice ( R. solani), leaf blight of oilseed rape ( S. sclerotiorum) and fruit rot of strawberry ( B. cinerea). A significant ( P < 0.05) suppression of the mycelial growth of R. solani, S. sclerotiorum and B. cinerea by the VS of S. platensis was observed. The potential of using VS of S. platensis F-1 as a biofumigant to control plant fungal diseases is discussed.

Effects of Carbon Tetrachloride on Perfused Cultures of Hepatic and Neuronal Cells

Cultured hepatocytes and hemisphere neurons from chick embryos and mouse neuroblastoma cells were exposed to carbon tetrachloride (CC14; 0, 1, 2, 3 and 4mM) for 1 hour, using a perfusion system developed for studying the effects of volatile substances. In the perfused cultures, three parameters were compared: lipid peroxidation, membrane integrity and cellular respiration. In addition, cytochrome C oxidase activity was determined after incubation of cell homogenates with CC14. A concentration-dependent increase in lipid peroxidation and membrane permeability was found in the neuroblastoma cells. The hepatocytes responded to a lesser extent with respect to membrane permeability and their lipid peroxidation did not differ from that of controls. The hepatocytes responded with a 35% decrease in respiration when exposed to 3mM CC14, and a 20% decrease in cytochrome C oxidase activity after treatment with 1.5mM CCl4. In the neuronal cells, much smaller decreases in respiration were found and their cytochrome C oxidase activity remained unaffected. These results are very similar to those obtained after incubation in a closed chamber system. However, the perfused cells were found to be less sensitive to CCl4than cells exposed under static conditions.

Effect of Volatile Substances from Species of Labiatae on Rhizospheric and Phyllospheric Fungi of Phaseolus vulgaris

Effect of Volatile Substances from Species of <i>Labiatae</i> on Rhizospheric and Phyllospheric Fungi of <i>Phaseolus vulgaris</i>

Effect of Volatile Substances from Safflower on Germination of Teliospores of Puccinia carthami

Effect of Volatile Substances from Safflower on Germination of Teliospores of Puccinia carthami

A Continously Recording Flight Mill for Investigating the Effect of Volatile Substances on the Flight of Tethered Insects1

An apparatus was developed to test and record the effect of volatile substances on the flight of tethered insects. It consists of a rotary flight mill within a glass chamber through which there is a continuous air flow, and a photocell-ratemeter-paper chart recording system. This system provides a permanent quantitative record of flight speed and duration and shows immediate and subtle changes in flight speed. The apparatus can be adapted for computer programming by a digital voltmeter and tape punch. Introduction of sex pheromone (as female frass) into the flight chamber caused male Douglas-fir beetles, Dendroctonus pseudotsugae Hopkins, and striped ambrosia beetles, Trypodendron lineatum (Olivier), to cease flight abruptly. This is considered to be strong evidence for the arrestant effect of pheromones on flying scolytids. The apparatus has promise as a tool in the study of the effect of pheromones and volatile host attractants on flying insects.

Význam těkavých látek v pivovarské výrobě.

Význam těkavých látek v pivovarské výrobě.

The Effect of Volatile Substances on the Chemical Activity of Ultrasonic Cavitation.

The Effect of Volatile Substances on the Chemical Activity of Ultrasonic Cavitation.