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Species Invasions in Freshwater Ecosystems
Published in Kezia Barker, Robert A. Francis, Routledge Handbook of Biosecurity and Invasive Species, 2021
Robert A. Francis, Michael A. Chadwick
There are other chemicals that can be used for control – for example, semiochemicals (such as pheromones) to entice animals into traps or disrupt animal behaviour such as mating (Dunn, 2012; Suckling, 2015) – but the use of semiochemicals is complex and has had limited application so far, despite its potential (Suckling, 2015).
Insight into Knapsack Metabolite Ecology Database: A Comprehensive Source of Species: Voc-Biological Activity Relationships
Published in Raquel Cumeras, Xavier Correig, Volatile organic compound analysis in biomedical diagnosis applications, 2018
Azian Azamimi Abdullah, M.D. Altaf-Ul-Amin, Shigehiko Kanaya
Conventional agricultural industry relies on a wide use of chemical pesticides and fertilizers. However, increased demand for organic products shows that consumers prefer reduced chemical use. Therefore, a novel sustainable agriculture needs to be developed for crop protection and prevention from using harmful chemicals. VOCs emitted by bacteria and fungi might have the potential as an alternative to the use of chemical pesticides to protect plants from pests and pathogens (Kanchiswamy et al., 2015a). It is because VOCs released by some rhizobacteria can enhance plant growth as well as inhibit the growth of other microorganisms. For example, acetoin and 2,3-butanediol released by rhizobacteria were found to promote the growth of Arabidopsis thaliana seedlings (Kai et al., 2016). A number of frequently emitted VOCs such as hexanal and 2-E-hexenal show antifungal activity and have been developed as an alternative to synthetic chemicals (Ayseli and Ayseli, 2016). Chemical ecologists also consider microbial VOCs as potential signaling molecules or semiochemicals that function as attractants and repellents to insects and other invertebrates. Pheromone traps are VOC based equipment for controlling pests without using harmful pesticides. In this strategy, pest insects may be diverted away from high-value crops using attractants, while simultaneously being repelled from high-value crops with repellents. Furthermore, natural enemies of insect pests, which are predators and parasitoids, may be simultaneously attracted making the use of semiochemicals a much more viable integrated management strategy than broad-spectrum chemical insecticides. For agriculture scientists, microbial VOCs are seen as biocontrol agents to control various phytopathogens and as biofertilizers for plant growth promotion (Kanchiswamy et al., 2015b). These examples indicate that the VOCs might have a potential impact on crop welfare and sustainable agriculture.
Use of Linear Retention Indices in GC-MS Libraries for Essential Oil Analysis
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Emanuela Trovato, Giuseppe Micalizzi, Paola Dugo, Margita Utczás, Luigi Mondello
Some of the most important retention index compilations are available in printed format, such as published as books and widely used as references, as those authored by Jennings and Shibamoto (1980) (Huethig Verlag: Heidelberg, Germany) containing MS spectra and KI on methyl silicone and on PEG stationary phase of more than 1150 flavor and fragrance compounds and by Adams (2007) (FarHawk, Fineview, NY, US), including spectral information and KI and AI of 2205 essential oil constituents. A further available library book is the Sadtler Standard Gas Chromatography Retention Index Library, reporting multi-RI on three different columns of over 2000 compounds (Sadtler Research Laboratories, 1984). An important reference dataset is the Joulain and König hydrocarbon sesquiterpene MS library of 307 components along with their RI calculated on a 25 m fused-silica capillary column coated with 100% dimethyl polysiloxane (Joulain and König, 1998). Worth noting is the compilation and evaluation of Babushok of the average or median RIs with standard deviations and confidence intervals of over 500 frequently reported essential oil constituents from the National Institute of Standards and Technology (NIST) data collection (Babushok et al., 2011). RI databases also can be available from the internet. The most known online RI datasets are the LRI & Odor Database (Mottram), the Flavornet (Acree and Arn, 2004), and the Pherobase (El-Sayed, 2003). The latter is the largest database of behavior-modifying chemicals with over 30,000 entries, among them about 3500 semiochemicals. Furthermore, related KIs are also reported according to cited values on different stationary phases in scientific papers. The website includes an interactive feature for the calculation of LRI of the target molecule and then allows an automatic search in the database according to the LRI filter window setting. Flavornet (Acree and Arn, 2004) lists 738 odorants along with their chromatographic and sensory properties. Chromatographic data include KI calculated with n-alkanes and ethyl esters on four different columns. The first-mentioned database reports over 9000 LRI values of more than 5000 odor compounds identified in food samples. The listed LRIs calculated on different stationary phases with n-alkanes were obtained from the scientific literature. On the website, a search feature helps the user, providing filters for different column types, molecular weight, and LRI within the filter window.
Insecticide potential of two saliva components of the predatory bug Podisus nigrispinus (Heteroptera: Pentatomidae) against Spodoptera frugiperda (Lepidoptera: Noctuidae) caterpillars
Published in Toxin Reviews, 2022
Juliana Mendonça Campos, Luis Carlos Martínez, Angelica Plata-Rueda, Wolfgang Weigand, José Cola Zanuncio, José Eduardo Serrão
Podisus nigrispinus adults were obtained from the mass rearing of the Biological Control Laboratory of the Institute of Biotechnology Applied to Agriculture (BIOAGRO) of the Federal University of Viçosa (UFV), in Viçosa, Minas Gerais state, Brazil. Insects were maintained at 25 ± 2 °C, 75 ± 5% relative humidity, and 12:12 h (light:dark) photoperiod. These insects were fed on Tenebrio molitor L. (Coleoptera: Tenebrionidae) pupae and Eucalyptus grandis (W. Hill ex Maiden) leaves ad libitum. Spodoptera frugiperda caterpillars were obtained from the Semiochemical Laboratory of the Department of Entomology of UFV. Caterpillars were kept in polyethylene boxes (15 × 9 cm) at 25 ± 2 °C, 75 ± 5% relative humidity, 12 h photophase, and fed on artificial diet containing 10 g of agar, 15.6 g of brewer yeast, 25 g of wheat germ, 25 g of soy protein, 31.2 g of bean, 12.5 g of casein, and 2.5 ml of vitamin solution (1.2% ascorbic acid, 0.03% calcium pantothenate, 0.015% niacin, 0.008% riboflavin, 0.004% thiamine, and 0.004% HCl) (Greene et al. 1976). Podisus nigrispinus adults and fifth instar S. frugiperda caterpillars without malformations were used in the bioassays.
Can Plasmodium’s tricks for enhancing its transmission be turned against the parasite? New hopes for vector control
Published in Pathogens and Global Health, 2019
S. Noushin Emami, Melika Hajkazemian, Raimondas Mozūraitis
Mosquitoes’ unique bionomics guarantee an efficient vector–host interaction, favorable for malaria transmission. Mosquitoes use several senses to locate and choose a host, predominantly olfaction [5,6]. The semiochemical basis of human host seeking has been studied during past years [7–9], allowing us to further characterize the basis of this important behavior. The best-known cue for activation and attraction is carbon dioxide (CO2), which is emitted by vertebrates through red blood cells, breath and skin, and indicates the presence of a potential host [6,10,11]. Mosquitoes also respond to the temperature of mammals and birds and the faster transport of odor by the heat convention current, resulting from metabolic activity [12,13]. Body heat and mass have a direct effect on the dispersal of chemicals, thus influencing mosquito [An. atroparvus and An. gambiae s.s.] attraction to the host behavior [14]. Once mosquitoes detect, land, and start to feed on a suitable host the volume and speed at which blood is taken varies. This complex behavior is dependent on feeding stimulation, olfactory apparatus, host defense, and neurophysiological pathways connected to the mosquito’s mouthparts which consequently boost the basic reproduction rate of pathogen transmission as well [5,15,16]. The avidity of the vector for a blood meal is measured as persistence (time spent feeding) and the number of times a mosquito attempts to find blood by inserting its proboscis (probing). Increased probing can enhance the chance of malaria parasite sporozoite transmission to the host blood vessels. It also risks being killed by the host defense or picking up of increased dose of insecticide. The volume of blood taken, and the speed of feeding has a direct effect on the likelihood of a mosquito becoming infected and subsequently transmitting the parasite [17]. Larger blood meals increase the chances of taking up infectious gametocytes and therefore infection and faster feeding rates are correlated with higher survival of mosquitoes due to host bite avoidance behavior. Whatever the mechanisms responsible for blood seeking/feeding behavior, malaria parasite seems to modify them to increase its transmission.