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Hesperidin is a highly bioactive natural flavonoid whose role in ecological interactions is poorly known. In particular, the effects of hesperidin on herbivores are rarely reported. Flavonoids have been considered as prospective biopesticides; therefore, the aim of the present study was to examine the influence of hesperidin on the host plant selection behavior of three aphid (Hemiptera: Aphididae) species: Acyrthosiphon pisum Harrris, Rhopalosiphum padi (L.), and Myzus persicae (Sulz.). The aphid host plants were treated with 0.1% and 0.5% ethanolic solutions of hesperidin. Aphid probing behavior in the no-choice experiment was monitored using electropenetrography and aphid settling on plants in the choice experiment was recorded. The results demonstrated that hesperidin can be applied as a pre-ingestive, ingestive, and post-ingestive deterrent against A. pisum, as an ingestive deterrent against R. padi, and as a post-ingestive deterrent against M. persicae using the relatively low 0.1% concentration. While in A. pisum the deterrent effects of hesperidin were manifested as early as during aphid probing in peripheral plant tissues, in M. persicae, the avoidance of plants was probably the consequence of consuming the hesperidin-containing phloem sap. [ABSTRACT FROM AUTHOR]

Sesame Fusarium wilt (SFW), caused by Fusarium oxysporum f. sp. sesami (Fos), is one of the most devastating diseases affecting sesame cultivation. Deciphering the genetic control of SFW resistance is pivotal for effective disease management in sesame. An inheritance study on a cross between the highly resistant variety Yuzhi 11 and the highly susceptible accession Sp1 using a Fos pathogenicity group 1 isolate indicated that resistance was conferred by a single dominant allele. The target locus was located in a 1.24 Mb interval on chromosome 3 using a combination of cross-population association mapping and bulked segregant analysis. Fine genetic mapping further narrowed the interval between 21,350 and 21,401 kb. The locus Sindi_0812400 was identified as the SFW resistance gene and officially designated SiRLK1. This gene encodes a specific malectin/receptor-like protein kinase with three putative tandem kinase domains and is considered a kinase fusion protein. Sequence analysis revealed that a high proportion (49.44%) of variants within the locus was located within the kinase domain III, and several of which were evidently associated with the diversity in SFW response, indicating the critical role of kinase domain III in expression of disease resistance. These findings provide valuable information for further functional analysis of SFW resistance genes and marker-assisted resistance breeding in sesame. [ABSTRACT FROM AUTHOR]

Antifeedant and contact repellent activity of thyme, tarragon, marigold and lavender crude extracts against the insect pest Epicauta atomaria Germar, 1821 (Coleoptera: Meloidae) was evaluated. The extracts were obtained by sequential maceration with dichloromethane, ethyl acetate and methanol. The antifeedant and contact repellent activity was evaluated by means of the feeding index and repellency percentage respectively. The results obtained indicate that the tarragon dichloromethane, ethyl acetate, and methanol extracts, lavender methanol extract and marigold and thyme ethyl acetate extracts, had a strong antifeedant activity against E. atomaria, both with median AI values of 100 %. On the other hand, only the lavender dichloromethane extract had a moderate repellent activity against E. atomaria, at all the exposure times evaluated, with median repellency percentage values of 60 %, 80 % and 50 % at 15, 30 and 60 minutes of exposure, respectively. [ABSTRACT FROM AUTHOR]

Hesperidin is a highly bioactive natural flavonoid whose role in ecological interactions is poorly known. In particular, the effects of hesperidin on herbivores are rarely reported. Flavonoids have been considered as prospective biopesticides; therefore, the aim of the present study was to examine the influence of hesperidin on the host plant selection behavior of three aphid (Hemiptera: Aphididae) species: Acyrthosiphon pisum Harrris, Rhopalosiphum padi (L.), and Myzus persicae (Sulz.). The aphid host plants were treated with 0.1% and 0.5% ethanolic solutions of hesperidin. Aphid probing behavior in the no-choice experiment was monitored using electropenetrography and aphid settling on plants in the choice experiment was recorded. The results demonstrated that hesperidin can be applied as a pre-ingestive, ingestive, and post-ingestive deterrent against A. pisum, as an ingestive deterrent against R. padi, and as a post-ingestive deterrent against M. persicae using the relatively low 0.1% concentration. While in A. pisum the deterrent effects of hesperidin were manifested as early as during aphid probing in peripheral plant tissues, in M. persicae, the avoidance of plants was probably the consequence of consuming the hesperidin-containing phloem sap.

Fall armyworm or Spodoptera frugiperda is one of the main pests of corn. It can caused up to 28.08% yield loss. Pest control efforts with broad-spectrum insecticides can cause negative impacts that disrupt ecosystems, non-target biotic factors and the surrounding environment. Beauveria bassiana is an alternative biological control agent that is target-specific. This study was conducted to determine toxic and antifeedant activities of B. bassiana application on third to fifth-instar S. frugiperda larvae. B. bassiana isolates were propagated using corn flakes media and resulted in colonies with conidia density of 1.1×108conidia.g-1. This study used a completely randomized design with 5 treatments and 5 replications. Treatments consisted of P1 namely B. bassiana propagation with a concentration of 60 g.L-1, P2 = 70 g.L-1, and P3 = 80 g.L-1. P0 was a negative control (untreated with B. bassiana) and P4 was a positive control (diazinon with concentrations of 2 ml.L-1). The variables observed were mortality and weight of the leftover feed. The results showed that the formulation of B. bassiana with concentrations of 80 g.L-1 was able to infect armyworms with a mortality percentage of 53.5% which was statistically similar as the effect of chemical insecticides. In addition, inhibition of feeding activity due to treatment could prevent leaf damage up to 68.21%.

Understanding foraging preferences of honey bees (Apis mellifera L.) is essential to maneuver pollinator movement to enhance outcrossing and hence the crop yields. In this communication, we report the role of floral volatile organic compounds (VOCs) in structuring foraging decisions of honey bees. Supercritical fluid extraction of VOCs, coupled with gas chromatography-mass spectrometry, revealed 75 VOCs. Of these, 19 were strong attractants and 8 were strong repellants. Moreover, we detected significant, but variable, species- or genome-level differences in floral scents. Honey bees avoided Brassica juncea cv. PBR357 (0.81 bee visits/sq m/min) and B. carinata cv. PC5 (0.77 bee visits/sq m/min), which possessed peak concentrations of antifeedants or repellents (dibutyl phthalate and 9-octadecenoic acid) in their floral volatiles. B. napus cvs. GSC6 and GSC7 attracted the highest number of bee visitations (1.07 and 0.99 bee visits/sq m/min, respectively), as these possessed VOCs with honey-fruity odor in high amounts and negligible levels of antifeedants. Our results highlight that variability in floral reward chemistry should be considered when breeding crops that are frequently visited upon by bee pollinators to support bee pollinators, in general, and honey industry, in particular. [ABSTRACT FROM AUTHOR]

Geranylacetone and nerylacetone are natural sesquiterpenoids, which play various roles in plant-insect interactions, including the deterrent and repellent effects on herbivores. The structural modifications of natural compounds often change their biological activities. The aim of the study was to evaluate the effect of geranylacetone, nerylacetone and their epoxy-derivatives on the probing and settling behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae). The no-choice test using the Electrical Penetration Graph (EPG) technique showed that the probes before the first phloem phase were usually shorter than 3 min, which means that they were terminated within the epidermis and/or outer layers of mesophyll. This resulted in a tendency to delay the initiation of the phloem phase in aphids, which reflects a weak preingestive deterrent activity of the studied compounds at the level of non-vascular tissues. Most M. persicae showed bouts of sustained phloem sap ingestion. However, the 24-h free-choice test demonstrated that aphids did not settle on the leaves treated with geranylacetone, nerylacetone, and their epoxy-derivatives. The refusal to settle after the consumption of phloem sap on treated plants indicated that the studied compounds had postingestive deterrent activity. The epoxidation of geranylacetone and nerylacetone did not evoke significant changes in their activity profiles. [ABSTRACT FROM AUTHOR]

Abstract Background Spodoptera exigua Hübner (Lepidoptera: Noctuidae) is a widely occurring insect pest of several crops conventionally controlled by pyrethroids and organophosphates hazardous for the environment and human health. Thus, the alternatives are biocide-based phytochemicals. Accordingly, the Piper ribesioides Wall. (Piperales: Piperaceae) plant, well distributed in the northern regions of Thailand (Nan Province), was used due to its known bioactivity against insects. The objective was to determine the feeding deterrent activity of P. ribesioides extracts and isolated allelochemicals under laboratory conditions and correlate the efficacy under greenhouse conditions after the extracts were applied to S. exigua larvae infesting potted Brassica oleracea var. alboglabra (Bailey) Musil plants. Another objective was to look at the impact of spray applications on detoxification enzymes to check the possibility of resistance development against such natural extracts. Results Ethyl acetate extract deterred feeding of larvae better than other extracts with the concentrations causing 50% feeding inhibition (FI50) of 26.25 µg/cm2 and feeding deterrence index (FDI) of 91.8%, which was slightly lower than the positive control (cypermethrin, FDI = 100%; FI50 0.027 µg/cm2). The most effective feeding deterrent compounds against S. exigua were pinostrobin and pinocembrin with FDI range of 77 to 90% and FI50 values of 14.39 and 19.38 µg/cm2. In the greenhouse, the larvae treated on potted B. oleracea at FI50 concentrations (determined in laboratory experiments), ethyl acetate extract gave the highest mortality of 63.33% within 24 h of first spray and total of 73.33% after 24 h of the second spray. Impact on detoxification enzymes (24 h post-treatment) was determined from survived 3rd instars of S. exigua using spray applications. Inhibition of carboxylesterase (CE) was 1.94-fold after hexane extract treatment. However, ethyl acetate extract inhibited glutathione-s-transferase (GST) 1.30-fold. Conclusions Ethyl acetate extract of P. ribesioides twigs and isolated pinostrobin and pinocembrin compounds were potential antifeedants against S. exigua larvae. The data obtained also showed that such antifeedant levels of treatment could be used in greenhouse or field trials directly as an extract after establishing the efficacy of extracts and the active compounds therein under laboratory conditions. Graphical Abstract

The environmental and health risks associated with synthetic pesticides have increased the demand for botanical insecticides as safer and biodegradable alternatives to control insect pests in agriculture. Hence in this study, five Meliaceae species were evaluated for their insecticidal activities against the Spodoptera frugiperda and the Plutella xylostella larvae, as well as their chemical constituents. Repellence, feeding deterrence, and topical application bioassays were employed to evaluate their insecticidal activities. GC-MS analysis was performed to identify chemical compounds present in each plant. The repellence bioassay indicated that Melia azedarach extracts exhibited the highest repellence percentage against S. frugiperda (95%) and P. xylostella (90%). The feeding deterrence bioassay showed that M. azedarach and Trichilia dregeana extracts displayed excellent antifeeding activity against the S. frugiperda (deterrent coefficient, 83.95) and P. xylostella (deterrent coefficient, 112.25), respectively. The topical application bioassay demonstrated that Ekebergia capensis extracts had the highest larval mortality against S. frugiperda (LD50 0.14 mg/kg). Conversely, M. azedarach extracts showed the highest larval mortality against P. xylostella (LD50 0.14 mg/kg). GC-MS analysis revealed that all plant extracts had compounds belonging to the two noteworthy groups (phenols and terpenes), which possess insecticidal properties. Overall, this study lends scientific credence to the folkloric use of Meliaceae species as potential biocontrol agents against insect pests. [ABSTRACT FROM AUTHOR]

The vegetable leafminer (VLM) Liriomyza sativae Blanchard is a troublesome pest of vegetable and ornamental plants worldwide. Resistance development and environmental pollution from the overuse of chemical insecticides have driven interest in alternative control strategies for this pest. Secondary metabolites derived from aromatic nonhost plants are recognised components of the plant defence system against herbivores. The essential oils derived from aromatic plants not only repel insects but also have toxic effects against various insect pests, yet little is known about their effects against leafminers. The major constituents of the essential oil extracted from rosemary leaves by hydrodistillation were identified by GC–MS. The behavioural responses of VLM adults to the rosemary essential oil (REO) were explored with Y‐tube olfactometer experiments, and the oviposition and feeding deterrent effects of REO against adults were studied using no‐choice cage tests. Dipping methods were used to determine the toxicity of REO and Matrine (a commercial botanical pesticide) against VLM eggs, larvae and pupae, while glass‐vial bioassays were used for adults. The identified major constituents of the cineoliferum chemotype of REO were 1,8‐cineole (23.53%), pinene (23.45%), (S)‐(−)‐verbenone (12.84%) and borneol (7.47%). REO repelled leafminer adults. Sublethal concentrations of REO deterred oviposition and feeding by adults. Adults were more susceptible than other developmental stages to toxicity of REO and Matrine. Female adults were more sensitive than males, based on EC50 values at 24 and 48 hr after treatment. Rosemary essential oil is a behaviour‐modifying stimulus potentially useful in a "push‐pull" strategy for L. sativae control, and as an alternative to synthetic chemical insecticides due to its low toxicity and high efficacy in the control of VLM. [ABSTRACT FROM AUTHOR]

Progress in the development of biodegradable or biobased ionic liquids (ILs) has led to the design of green compounds for several applications. Herein, four biocompatible dicationic ionic liquids (DILs) with ammonium-phosphonium cations and amino acid anions were synthesized and investigated their environmental impact. The structures of the DILs were confirmed by spectral analyses (1H, 13C and 31P NMR). Furthermore, physicochemical properties such as density, viscosity and refractive index were determined. Water content, bromide content and solubility were thereafter determined as the parameters needed for further studies. Subsequently, their antifeedant activity towards economically important pests of grain in storage warehouses: the granary weevil, the confused flour beetle, and the khapra beetle was examined, showing the dependence on structure. Moreover, selected DILs were investigated for toxicity towards white mustard, Daphnia magna , and Artemia franciscana to specify the environmental impact. These studies were complemented by understand the biodegradation of DILs by bacterial communities derived from soil at the agricultural land. The result was DILs with limited environmental footprints that have great potential for further application studies. [Display omitted] • A novel approach to synthesizing dicationic ionic liquids with ammonium-phosphonium cation was presented. • Spectral analysis (1H, 13C, and 31P NMR) was used to characterize the structure of the synthesized dicationic ionic liquids. • Ecotoxicological assessment of the impact of dicationic ionic liquids on storage pests, plant, and crustaceans was carried out. • The biodegradability of dicationic ionic liquids was investigated to assess their influence in the environment. [ABSTRACT FROM AUTHOR]

Laboratory experiment was conducted to evaluate the bioefficacy of ethnobotanical plant Lippia javanica at Entomology laboratory at IFB, Hyderabad during 2016-2018. Experiment was carried out in Completely Randomized Design and antifeedant activity and toxicity was observed in the plant extracts based on the feeding behavior of the test insect and arranged in the descending order is 1.0%>0.8%>0.6%>0.4%>0.2%>0.1% concentrations and uncontrol. The insect culture was maintained in a growth chamber in the laboratory at a temperature of 27 ± 2°C, 12: 12 L:D and with 70 ± 5 % RH during the experiments. Hence depending upon the pest problem, a particular type of extract has to be applied for effective control of the pest. [ABSTRACT FROM AUTHOR]

Background: Spodoptera exigua Hübner (Lepidoptera: Noctuidae) is a widely occurring insect pest of several crops conventionally controlled by pyrethroids and organophosphates hazardous for the environment and human health. Thus, the alternatives are biocide-based phytochemicals. Accordingly, the Piper ribesioides Wall. (Piperales: Piperaceae) plant, well distributed in the northern regions of Thailand (Nan Province), was used due to its known bioactivity against insects. The objective was to determine the feeding deterrent activity of P. ribesioides extracts and isolated allelochemicals under laboratory conditions and correlate the efficacy under greenhouse conditions after the extracts were applied to S. exigua larvae infesting potted Brassica oleracea var. alboglabra (Bailey) Musil plants. Another objective was to look at the impact of spray applications on detoxification enzymes to check the possibility of resistance development against such natural extracts. Results: Ethyl acetate extract deterred feeding of larvae better than other extracts with the concentrations causing 50% feeding inhibition (FI50) of 26.25 µg/cm2 and feeding deterrence index (FDI) of 91.8%, which was slightly lower than the positive control (cypermethrin, FDI = 100%; FI50 0.027 µg/cm2). The most effective feeding deterrent compounds against S. exigua were pinostrobin and pinocembrin with FDI range of 77 to 90% and FI50 values of 14.39 and 19.38 µg/cm2. In the greenhouse, the larvae treated on potted B. oleracea at FI50 concentrations (determined in laboratory experiments), ethyl acetate extract gave the highest mortality of 63.33% within 24 h of first spray and total of 73.33% after 24 h of the second spray. Impact on detoxification enzymes (24 h post-treatment) was determined from survived 3rd instars of S. exigua using spray applications. Inhibition of carboxylesterase (CE) was 1.94-fold after hexane extract treatment. However, ethyl acetate extract inhibited glutathione-s-transferase (GST) 1.30-fold. Conclusions: Ethyl acetate extract of P. ribesioides twigs and isolated pinostrobin and pinocembrin compounds were potential antifeedants against S. exigua larvae. The data obtained also showed that such antifeedant levels of treatment could be used in greenhouse or field trials directly as an extract after establishing the efficacy of extracts and the active compounds therein under laboratory conditions. [ABSTRACT FROM AUTHOR]

Geranylacetone and nerylacetone are natural sesquiterpenoids, which play various roles in plant-insect interactions, including the deterrent and repellent effects on herbivores. The structural modifications of natural compounds often change their biological activities. The aim of the study was to evaluate the effect of geranylacetone, nerylacetone and their epoxy-derivatives on the probing and settling behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae). The no-choice test using the Electrical Penetration Graph (EPG) technique showed that the probes before the first phloem phase were usually shorter than 3 min, which means that they were terminated within the epidermis and/or outer layers of mesophyll. This resulted in a tendency to delay the initiation of the phloem phase in aphids, which reflects a weak preingestive deterrent activity of the studied compounds at the level of non-vascular tissues. Most M. persicae showed bouts of sustained phloem sap ingestion. However, the 24-h free-choice test demonstrated that aphids did not settle on the leaves treated with geranylacetone, nerylacetone, and their epoxy-derivatives. The refusal to settle after the consumption of phloem sap on treated plants indicated that the studied compounds had postingestive deterrent activity. The epoxidation of geranylacetone and nerylacetone did not evoke significant changes in their activity profiles.

In the search for new plant‐derived products with antifeedant and insecticidal potential against economically important insects, 11 grindelanes (two as natural acids and nine as methylated derivatives) purified from the foliar tissue of Grindelia chiloensis (Cornel.) Cabrera (Asteraceae) were evaluated against the fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae). Larvae of this moth are considered to be the main pest of maize that causes severe losses on local agricultural production. Remarkable alterations in feeding behavior, larval weight, larval and pupal stage lengths, and adult fertility, as well as malformations and mortality in specimens during their life cycle were noticed in the feeding preference tests and no‐choice diet assays. Antifeedant indexes (AI%) calculated in food preference bioassays reached up to 79% for the lipophilic grindelane 3b, the most potent antifeedant agent. Grindelane 7b showed a better insecticidal activity (median lethal dose, LD50 = 26.49 µg g−1) and 8b was potentially neurotoxic due to acetylcholinesterase inhibition. Ultrastructure of the middle portion of the digestive tract of larvae fed with small amounts of natural grindelane 9a supplemented to the diet revealed cell damage, and thickening of the peritrophic membrane and a striking number of mitochondria, as evident signs of defense against toxic substances ingested by the larvae. Besides, this study demonstrated that these effective insecticides did not have inhibitory effects on beneficial plant and soil bacteria which would allow ecological pest management. [ABSTRACT FROM AUTHOR]

The environmental and health risks associated with synthetic pesticides have increased the demand for botanical insecticides as safer and biodegradable alternatives to control insect pests in agriculture. Hence in this study, five Meliaceae species were evaluated for their insecticidal activities against the Spodoptera frugiperda and the Plutella xylostella larvae, as well as their chemical constituents. Repellence, feeding deterrence, and topical application bioassays were employed to evaluate their insecticidal activities. GC-MS analysis was performed to identify chemical compounds present in each plant. The repellence bioassay indicated that Melia azedarach extracts exhibited the highest repellence percentage against S. frugiperda (95%) and P. xylostella (90%). The feeding deterrence bioassay showed that M. azedarach and Trichilia dregeana extracts displayed excellent antifeeding activity against the S. frugiperda (deterrent coefficient, 83.95) and P. xylostella (deterrent coefficient, 112.25), respectively. The topical application bioassay demonstrated that Ekebergia capensis extracts had the highest larval mortality against S. frugiperda (LD50 0.14 mg/kg). Conversely, M. azedarach extracts showed the highest larval mortality against P. xylostella (LD50 0.14 mg/kg). GC-MS analysis revealed that all plant extracts had compounds belonging to the two noteworthy groups (phenols and terpenes), which possess insecticidal properties. Overall, this study lends scientific credence to the folkloric use of Meliaceae species as potential biocontrol agents against insect pests.

Results showed that emamectin benzoate 0.0025% and chlorfenapyr 10 SC @ 0.01% gave cent per cent protection to Virginia tobacco against Spodoptera litura infestation followed by metaflumizone 22 SC @ 0.04%. The mean number of leaves damaged, the leaf area damaged and mean number of plants infested in the treatments of emamectin benzoate and chlorfenapyr were on at par with each other and significantly less than all other treatments followed by metaflumizone. These treatments also recorded higer yield parameters in terms of cured leaf, bright leaf and grade index. Chlorfenapyr 10 SC @ 0.01% and metaflumizone 22 SC @ 0.04% can be used for management of S.litura in Virginia tobacco along with emamectin benzoate 5 SG @ 0.0025%. [ABSTRACT FROM AUTHOR]

Investigations were carried out to assess the effect of water extracts of seven plant species namely Neem, Gulabas, Forest jasmine, Chinese arborvitae, Spreading hogweed, Tridex and Parthenium leaves on feeding growth and development of Spodoptera litura larvae under laboratory condition. Among the seven plant species, promising results were obtained only with two plant extracts namely Neem and Forest Jasmine. Antifeedant action, growth inhibition and larval mortality were significantly highest in these two extracts indicating their potential use in the management of Spodoptera litura population under field condition. [ABSTRACT FROM AUTHOR]

In this exploratory study, the antifeedant activity of ethanolic extracts of nine plants native from central region of Argentina on Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) was evaluated, looking for low environmental impact management alternatives. Adults of A. diaperinus were exposed to food treated with the extracts to assess whether feeding behaviour and survival were altered. None of the extracts affected adult survival. However, the extracts of Gaillardia megapotamica, Vernonanthura nudiflora, Baccharis artemisioides, Lithraea molleoides, and Ambrosia artemisiifolia had a strong antifeedant effect (92-96%). The other extracts evaluated slightly affected (50-55%) the food consumption. The extracts of G. megapotamica and B. artemisioides were administered with the food to the fifth larval stage to assess whether they affect survival, feeding behaviour, and weight of immature forms. The B. artemisioides extract generated a marked deterrent effect of feeding on the larvae (76%) during the first week of experimentation, although the effect In this exploratory study, the antifeedant activity of ethanolic extracts of nine plants native from central region of Argentina on Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) was evaluated, looking for low environmental impact management alternatives. Adults of A. diaperinus were exposed to food treated with the extracts to assess whether feeding behaviour and survival were altered. None of the extracts affected adult survival. However, the extracts of Gaillardia megapotamica, Vernonanthura nudiflora, Baccharis artemisioides, Lithraea molleoides, and Ambrosia artemisiifolia had a strong antifeedant effect (92-96%). The other extracts evaluated slightly affected (50-55%) the food consumption. The extracts of G. megapotamica and B. artemisioides were administered with the food to the fifth larval stage to assess whether they affect survival, feeding behaviour, and weight of immature forms. The B. artemisioides extract generated a marked deterrent effect of feeding on the larvae (76%) during the first week of experimentation, although the effect www.biotaxa.org/RSEA. ISSN 1851-7471 (online) Revista de la Sociedad Entomológica Argentina 79(4): 23-30, 2020 Copyright FERNÁNDEZ, N.F. et al.- This is an open access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0) 23 weakened over time. On the other hand, G. megapotamica produced a moderate deterrent effect (41-74%) throughout the experiment. The extracts also affected weight, survival, and number of larval exuviae in relation to the control. [ABSTRACT FROM AUTHOR]

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]

Shoot and fruit borer, Earias vittella (Fab.) is commonly encountered and economically important insect pest on okra (bhendi). Experiments were carried out to investigate the antifeedent and mortality activities of panchagavya alone and in combination with plant extracts against E. vittella in the laboratory and to evaluate the effectiveness in the field during rabi and kharif 2017 at C. Mutlur, Chidambaram. This study assessed five binary botanical extracts mixture with panchagavya used in vitro which included extracts containing panchagavya, neem leaf extract (NLE) 5%, Prosophis leaf extract 5%, Calotropis leaf extract 5%, Pungam oil 3% and NSKE 5%. Fruit disc no-choice methods were performed in a laboratory using bhendi fruit to determine the antifeedant activity and per cent mortality. Results indicated that all binary mixtures showed antifeedant activity and highest recorded was in NLE (5%) + panchagavya (3%) (65.11%) and was on par with NSKE (5%) (64.84%) and the highest mortality was recorded in panchagavya (3%) + NSKE (5%) (83.33%) followed by pungam oil 3% + panchagavya 3% (66.67%) and NLE 5% + panchagavya 3% (53.33%). Field studies indicated that highest per cent reduction of E. vittella was recorded in panchagavya (3%) + Neem Seed Kernel Extract (NSKE) (5%) treated plot followed by pungam oil 3% + panchagavya 3% and Neem Leaf Extract (NLE) 5% + panchagavya 3%. The field studies demonstrated that NSKE 5% in combination with panchagavya were effective in the management of E. vittella and could be an efective alternative to synthetic pesticides. [ABSTRACT FROM AUTHOR]

Rutin and its aglycone quercetin occur in the fruits, leaves, seeds, and grains of many plant species and are involved in plant herbivore interactions. We studied the effect of the exogenous application of rutin and quercetin on the probing behavior (= stylet penetration activities in plant tissues) of Acyrthosiphon pisum on Pisum sativum, Myzus persicae on Brassica rapa ssp. pekinensis, and Rhopalosiphum padi on Avena sativa using the electrical penetration graph technique (EPG = electropenetrography). The reaction of aphids to quercetin and rutin and the potency of the effect depended on aphid species, the flavonol, and flavonol concentration. Quercetin promoted probing activities of A. pisum within non-phloem and phloem tissues, which was demonstrated in the longer duration of probes and a trend toward longer duration of sap ingestion, respectively. M. persicae reached phloem in a shorter time on quercetin-treated B. rapa than on the control. Rutin caused a delay in reaching sieve elements by A. pisum and deterred probing activities of M. persicae within non-phloem tissues. Probing of R. padi was not affected by quercetin or rutin. The potency of behavioral effects increased as the applied concentrations of flavonols increased. The prospects of using quercetin and rutin in plant protection are discussed.

Essential oils are naturally occurring phytochemicals produced as secondary metabolite in plants. These are complex mixtures of volatile compounds and generally contain twenty to sixty individual compounds in different concentrations. They are lipophilic in nature and have density lower than water. These interfere with basic metabolic, biochemical, physiological and behavioral functions of insects. Several essential oils and its constituents have been established for their repellent, antifeedant, ovicidal, oviposition inhibitory and developmental inhibitory activities in insects. These insecticides probably interfere with the respiratory and nervous system of the insect to exert its actions. These essential oils provide an alternative source of insect control agents because they contain a range of bioactive chemicals, most of which are selective and have little or no harmful effect on the environment and the non-target organisms including human. Essential oils based formulations can be used as alternative tools in stored-grain insect management. DOI: http://dx.doi.org/10.5281/zenodo.3528366

Essential oils are naturally occurring phytochemicals produced as secondary metabolite in plants. These are complex mixtures of volatile compounds and generally contain twenty to sixty individual compounds in different concentrations. They are lipophilic in nature and have density lower than water. These interfere with basic metabolic, biochemical, physiological and behavioral functions of insects. Several essential oils and its constituents have been established for their repellent, antifeedant, ovicidal, oviposition inhibitory and developmental inhibitory activities in insects. These insecticides probably interfere with the respiratory and nervous system of the insect to exert its actions. These essential oils provide an alternative source of insect control agents because they contain a range of bioactive chemicals, most of which are selective and have little or no harmful effect on the environment and the non-target organisms including human. Essential oils based formulations can be used as alternative tools in stored-grain insect management. [ABSTRACT FROM AUTHOR]

Synthetic chemical pesticides are well known to be the most effective way to protect the plants and their products. However, their indiscriminate use has caused severe toxic effects on the environment, useful microbes, and animal and human health. Plant-based biopesticides have been shown to be better alternatives as compared to the synthetic pesticides as they show no residual toxicity in soil and are considered eco-friendly. This review aims to provide existing knowledge on the subject in the sub-Saharan African region where plants have been used traditionally as insecticides. These plants have proven insecticidal and chemical properties, documented in the literature. The survey identified 92 plant species distributed in 38 families, which are used throughout the sub-Saharan African region as insecticides against beetles, aphids, termites, and flies. Plant species, such as Azadirachta indica, Bidens pilosa, and Lantana camara, were recorded to be very effective plant-based insecticides. Several phytochemicals have been recorded in most plants and the presence of these chemicals may be responsible for their insecticidal properties. However, many others have not yet been tested, therefore, this review shows the need for further research where knowledge gaps exist. [ABSTRACT FROM AUTHOR]

The study reports efficacy of Melissa officinalis L. essential oil (MOEO) as a safe plant-based insecticide against Tribolium castaneum Herbst (TC) by induction of oxidative stress. MOEO nanoencapsulation in chitosan matrix was performed to enhance its bioefficacy. GC–MS analysis of MOEO depicted geranial (31.54%), neral (31.08%), and β-caryophyllene (12.42%) as the major components. MOEO showed excellent insecticidal potential in contact (100% mortality at 0.157 μL/cm2) and fumigant bioassays (LC50 = 0.071 μL/mL air) and 100% repellency at concentration ≤ 0.028 μL/cm2. Increased reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), and decreased ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) at the LC50 dose suggested significant oxidative stress on TC in MOEO treatment sets. The encapsulated MOEO exhibited enhanced activity as fumigant (LC50 = 0.048 μL/mL air) and showed significant antifeedant activity in situ (EC50 = 0.043 μL/mL). High LD50 value (13,956.87 μL/kg body weight of mice) confirmed favorable toxicological profile for non-target mammals. The findings depict potential of nanoencapsulated MOEO as an eco-friendly green pesticide against infestation of stored food by TC. [ABSTRACT FROM AUTHOR]

The biotransformation of (+)-isofraxinellone (1) by Aspergillus niger was investigated. Compound 1 was transformed to only one new compound 2. The structure of 2 was identified as (-)-(4S)-4-hydroxyisofraxinellone which was regio- and stereo-selective hydroxylated at the C-4 position by IR, EI-MS 1D and 2D NMR. Absolute configuration of hydroxyl group at the C-4 position was detected by modified Mosher's method. Antifeedant activity of compounds 1 and 2 against larvae of Spodoptera litura was assayed. These compounds showed potent antifeedant activity and ED50 (50% of effective dose) values were 3.91 and 4.43 μg/cm2, respectively. [ABSTRACT FROM AUTHOR]

Two new eremophilenolides, ligushicins A (1) and B (2), and two known compounds including β-sitosterol and ursolic acid were isolated from Ligulariopsis shichuana. The structures of new compounds were established on the basis of 1D and 2D NMR data and HRESIMS data interpretation. The absolute configuration of new compounds was assigned by ECD spectroscopy, and that of ligushicins A (1) was confirmed by X-ray diffraction analysis. The antifungal and antifeedant activities of new compounds were evaluated against four plant pathogenic fungi and third-instar larvae of Plutella xylostella, respectively. Ligushicins A (1) and B (2) exhibited potent antifungal activity against Botrytis cinerea and Fusarium oxysporum with minimum inhibitory concentration (MIC) values ranging from 50 to 100 mg/L, while they also exhibited weak antifeedant activities. [ABSTRACT FROM AUTHOR]

Collembola are one of the most abundant groups of arthropods, with fungi being an important part of their diet. Collembolan grazing of ectomycorrhizae (ECM) can sever connections between the host root and hyphal networks, interrupting nutrient flow and negatively impacting plant growth. Much of the previous information on interactions between Collembola and ECM has been based on mycelium grown in pure culture, which has artificially high nutrient levels and may lack physical and chemical grazing deterrents seen when ECM form on plant roots. We investigated Collembola feeding preferences by offering naturally occurring ECM, identified by ITS sequencing, to Folsomia candida and Protaphorura armata. We also assessed the gut content fungi of Folsomia collected in a mature Pinus strobus stand. We found that some ECM types, including the Tricholoma aestuans, Piloderma bicolor and the tuburculate ECM of Suillus spraguei, were readily grazed, while Cenococcum geophilum and Lactarius vinaceorufescens were unpalatable. Fungi forming unpalatable ECM were readily grazed when not in symbiosis with the host root. [ABSTRACT FROM AUTHOR]

Currently, the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is considered an agricultural and nuisance pest in Georgia. The invasive chinaberry tree, Melia azedarach L. (Meliaceae), commonly grows in dense thickets along roadsides, and in woodlands adjacent to agricultural crops across the southeastern USA. Thus, the objective of this study was to determine the potential of M. azedarach to serve as a host plant of H. halys by examining mortality and feeding of first and second instars on M. azedarach leaves vs. carrot (i.e., a control diet), and documenting presence of H. halys on M. azedarach in woodlands at 2 locations in Georgia where this stink bug has become established. Over all sampling dates and locations, the number of H. halys in chinaberry was very low (0.1 per tree), and only 3 late instars and 1 adult were observed feeding on M. azedarach at 1 field site late in the season. Percentage feeding by second instars of H. halys was lower for individuals given M. azedarach leaves vs. those provided with carrot, most likely indicating that compounds in M. azedarach have an antifeeding effect. In fact, mortality for second instars on M. azedarach leaves was very high, and thus we conclude that M. azedarach is an unsuitable host plant for H. halys. [ABSTRACT FROM AUTHOR]

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Abstract The proposed structure for a moss-produced acetylenic oxylipin (10-keto-type structure) was synthesized from a known glycidol derivative by an 11-step sequence involving epoxide ring opening with a terminal acetylene and enzymatic hydrolysis of a methyl ester intermediate. The NMR spectra of the proposed structure was, however, different from those of the natural oxylipin, which prompted us to synthesize its 9- epi -isomer and two diastereomeric 12-keto-type positional isomers. Comparison of the NMR spectra of the three isomers with those of the natural oxylipin indicated that the natural oxylipin was actually a mixture of the two diastereomeric positional isomers. Graphical abstract Image 1 Highlights • The proposed structure of a moss-produced acetylenic oxylipin was synthesized. • The proposed 10-keto-type structure was found to be incorrect by NMR comparison. • The oxylipin was a mixture of two diastereomeric 12-keto-type positional isomers. [ABSTRACT FROM AUTHOR]

Introduction: Ginsenosides, including protopanaxdiol (PPD) and protopanaxtriol (PPT) type ginsenosides, have been identified as natural insecticidess. This study aimed to investigate the antifeedant and ovicidal activities of total ginsenosides, protopanaxdiol saponins (PDS) and protopanaxtriol saponins (PTS) against Asian corn borer, O. furnacalis (Guenee). Methods and results: O. furnacalis egg masses (> 40 eggs) at 0-, 1- and 2-day-old were dipped into ginsenosides and egg hatchability was significantly inhibited by total ginsenosides, PDS, and PTS in dose and egg-age dependent manners. 100 mg/ml PDS had the strongest ovicidal activity against 0- (80.58 ± 0.95%), 1- (71.48 ± 5.70%), and 2-day-old eggs (64.31 ± 3.20%). In no-choice and choice feeding tests, we observed that the 3rd instar larvae consumed decreased area of leaves treated with ginsenosides, and the antifeedant activities of total ginsenosides, PDS, and PTS against the 3rd instar larvae were time and dose-dependent, with higher activities at 48 h. 100 mg/ml PDS had relative higher antifeedant activity (88.39 ± 3.43% in no-choice and 80.9±4.36% in choice) than total ginsenosides and PTS at all time intervals, except at 48 h in no-choice test. In further experiments, we found PPD ginsenosides (Rb1, Rb2, Rc, and Rd) had relative higher time and dose dependent antifeedant activities than PPT ginsenosides (Re and Rg1). Conclusions: Our results suggested the insecticidal action of total ginsenosides, PDS, and PTS on O. furnacalis. All ginsenosides, especially PDS, showed antifeedant and ovicidal activities against O. furnacalis. [ABSTRACT FROM AUTHOR]

Abstract The selection of foods in any environment depends on a variety of factors, including the nutrient availability and antifeedant loads in the component habitats. How these nutritional properties vary and covary in time and space is not well known, particularly among wild plant species. We collected plant samples from several habitats within the Cradle of Humankind World Heritage Site in South Africa, and measured their macronutrient and antifeedant properties in order to explore how season, habitat, plant type, and plant organ affected the quality of these potential plant foods. Our results have implications for early hominin use of similar habitats. Highlights • The nutritional properties of plants vary considerably. • Wetland habitats have surprisingly poor nutritional profiles. • Sedges, even those with large USOs, are lower-quality and unreliable foods. • Some woodland habitats have high protein and low antifeedant content. [ABSTRACT FROM AUTHOR]

Abstract Our previous studies had identified that both crude extracts and total alkaloid from Chelidonium majus exerted a significant antifeeding and larval lethality on Lymantria dispar. Moreover, sanguinarine, chelidonine, berberine hydrochloride and coptisine were the main alkaloid in C. majus exerting toxicity to L. dispar. In this paper, we evaluated the insecticidal and antifeeding activities of each alkaloid on the 3rd instar L. dispar larvae by bioassay. Meanwhile, the effects of alkaloids from C. majus on the activities and mRNA levels of three main digestive enzymes in L. dispar larvae were investigated. The results indicated that sanguinarine possessed the strongest insecticidal activity with a LD 50 value of 4.963 μg/larva, and the coptisine showed little lethality to 3 rd instar L. dispar larvae among four alkaloids from C. majus. The insecticidal capacity of four alkaloids on 3rd instar L. dispar larvae was in the following decreasing order of sanguinarine > chelidonine > berberine hydrochloride > coptisine. Similarly, except coptisine, the other three alkaloids significantly reduced food intakes of third instar L. dispar larvae and suppressed activities of three digestive enzymes (α-amylase, lipase and total protease) simultaneously. Finally, qRT-PCR analysis revealed that the transcriptions of α-amylase, lipase and serine protease were affected by sanguinarine. Especially, at 48 h after treatment, the mRNA expressions of those digestive enzymes were significantly suppressed by sanguinarine. In conclusion, we suggested that alkaloids from C. majus induced antifeeding and larval lethality on L. dispar larvae by suppressing food intake and digestive enzymes in L. dispar. Our findings provide a novel insight into evaluating the antifeeding and insecticidal properties of C. majus, which afford a new strategy for integrated pest management programs as well. Graphical abstract Unlabelled Image Highlights • Sanguinarine possessed the strongest insecticidal activity to 3 rd instar L. dispar larvae among four alkaloids from C. majus. • Sanguinarine, chelidonine and berberine hydrochloride significantly reduced food intakes of 3rd instar L. dispar larvae. • Three alkaloids from C. majus suppressed digestive enzyme activities of 3rd instar L. dispar larvae. • Sanguinarine affected transcriptions of α-amylase, lipase and serine protease in midguts of L. dispar larvae. [ABSTRACT FROM AUTHOR]

Insecticidal and antifeeding activities against Plutella xylostella were observed using whole‐plant‐derived Perilla frutescens material. The active ingredient in P. frutescens was identified by spectroscopic analysis as the sesquiterpenoid α‐farnesene, which showed insecticidal activity against third‐instar larva of P. xylostella in a leaf‐dipping bioassay based on 24‐h LD50 values (LD50 = 53.7 ppm). The feeding inhibition rate of α‐farnesene was 82.98% against P. xylostella at 10 ppm, and the antifeeding responses were determined using an oscilloscope to detect electrophysiological responses. The electrophysiological responses of the medial styloconic sensillum (MSS) were approximately 7‐fold more sensitive at 100 ppm than those of the lateral styloconic sensillum (LSS). These results suggest that the insecticidal and antifeeding effect of α‐farnesene, which is a P. frutescens‐derived material, can be used as a potential control agent for P. xylostella. [ABSTRACT FROM AUTHOR]

Core Ideas: More information is needed on non‐target turf injury caused by overspray of human insect repellents.There are differences in the magnitude of turf injury in response to human insect repellents.Significant turf injury for varying lengths of time may result from human insect repellent products, especially for products containing DEET. [ABSTRACT FROM AUTHOR]

Substances that alter insect behavior have attracted a lot of attention as potential crop protection agents. Naringenin (5,7,4′-trihydroxyflavanone) is a naturally occurring bioactive flavanone. We evaluated the influence of naringenin on aphid activities during individual phases of probing and feeding and the effect of structural modifications of naringenin on its activity towards aphids. We monitored the probing behavior of Myzus persicae (Sulz.) (Hemiptera: Aphididae) using the Electrical Penetration Graph (EPG) technique. The chemical modifications were the substitution of hydrogen atoms with methyl, ethyl or pentyl groups and the replacement of the carbonyl group in naringenin and its derivatives with an oxime moiety. Depending on the substituents, the activity of naringenin-derived compounds varied in potency and mode of action. Naringenin was an attractant of moderate activity, which enhanced sap ingestion. The naringenin derivative with two methyl groups—7,4′-di-O-methylnaringenin—was a deterrent, which hindered aphid probing in non-phloem tissues. Naringenin oxime derivatives with methyl substituents—7,4′-di-O-methylnaringenin oxime, 7-O-methylnaringenin oxime, and 5,7,4′-tri-O-methylnaringenin oxime—and the derivative with a pentyl substituent—7-O-pentylnaringenin oxime—were strong attractants which stimulated aphid probing in non-phloem tissues and the ingestion of phloem sap.

Graphical abstract Highlights • The total content of 9 ginsenosides from ginseng leaves and stems was 72.91 mg/mL measured by high-performance liquid chromatography method. • Total ginsenosides extracted from ginseng leaves and stems showed significant antifeedant activity on Plutella xylostella larvae. • The residue rate of 9 ginsenosides in the pest became gradually higher as applied concentration increased. • Feeding with ginsenosides generally resulted in change of the detoxication enzymes activity in Plutella xylostella. Abstract The diamondback moth, Plutella xylostella , is one of the most serious insect pests of cruciferous crops all over the world. Although chemical insecticides are used to control this pest, it develops resistance to almost all kinds of insecticides. In recent, triterpenoid saponins have been reported to show potent antifeedant or synergize insecticidal activity on several pests. Therefore, to assess the antifeedant activity of ginsenosides against P. xylostella is benefit to biological control of this pests. Total ginsenosides were extracted from ginseng leaves and stems, and the total content of 9 ginsenosides was 72.91 mg/mL measured by high-performance liquid chromatography (HPLC) method. Total ginsenosides extracted from ginseng leaves and stems showed significant antifeedant activity on P. xylostella larvae in both non-choice and choice assays. The concentration of median antifeedant (AFC 50) of total ginsenosides for the second instar larval of P. xylostella were 4.98 and 5.03 mg/mL at 24 h and 48 h respectively in non-choice assay, and they were 2.74 and 4.14 mg/mL respectively in choice assay. The residue rate of 9 ginsenosides in the pest became gradually higher as applied concentration increased. Feeding with ginsenosides generally resulted in decrease of glutathione S-transferase (GST), acetylcholine esterase (AChE), and carboxylesterase (CarE) activities, but increase of mixed-functional oxidase (MFO) activity in P. xylostella. These results indicate that ginsenosides are suitable for developing it into a botanical pesticide. [ABSTRACT FROM AUTHOR]

Cinnamic aldehyde (CA) is a major constituent of cinnamomum bark oil. Though there are reports on the antifeedant effect of CA in house rat, understanding its effect on behaviour and gastrointestinal tract of house rat is necessary to develop an effective formulation for its field application against commensal rodents. In the present investigation, rats were fed on plain bait and 5% CA treated bait both under no-choice and bi-choice conditions for 30 days. Results revealed its potential as an antifeedant against R. rattus under both no-choice and bi-choice conditions. However, antifeedant/secondary repellent effect of 5% CA was more under bi-choice conditions. Studies on feeding and tactile behaviour of rats in response to 5% CA also revealed its irritant effect. Histomorphological studies on stomach and intestine of 5% CA treated rats revealed that in no-choice group of rats, 5% CA caused hyperplasia of non-glandular stomach and also caused reduction in number of cells of both intestinal and gastric glands which might have caused reduction in secretion of digestive juices and hormones resulting in reduction in consumption of treated bait. But in bi-choice group, GI tract was not affected. Reduction in consumption of treated bait in bi-choice group of rats might have occurred due to its irritant effect on skin and eyes of rats causing rats to prefer alternate plain bait under bi-choice conditions. [ABSTRACT FROM AUTHOR]

The effect of alcohol extract and essential oil from Juniperus sabina L. (Cupressaceae) on the survival and nutrition of the larvae Galleria mellonella L. (Pyralidae) has been studied. It is found that the essential oil has insecticidal, antifeedant, deterrent, and repellent properties. The loss of larvae with topical application of 0.2 μL of essential oil to the dorsal part (contact action) reaches 64.0%. Feeding larvae with food treated with essential oil J. sabina (200 μL of essential oil per 1.5 g of feed) is reduced 2.1 times compared to the control. It is shown that larvae G. mellonella avoid feeding on oil-treated feed for 14 days and actively move in the opposite direction from the treated feed when they are placed in Petri dishes. It has been established that vapors of essential oil suppress the development of larvae G. mellonella even when fed with untreated food—there is a lag in body weight and a delay in molting in the next age. The essential oil J. sabina also exhibits moderate toxicity (20.0%) when the larvae eat the treated food, i.e., possess intestinal action. The alcohol extract of J. sabina at a concentration of 2.5% of active substances (on dry residue) has a negligible effect on the loss of larvae in the case of treated feed (10.0% contact action). With topical application to the dorsal part, the extract causes 20.0% insect death. An alcohol extract of J. sabina does not elicit any antifeedant or repellent properties against larvae; however, a low level of deterrental activity, expressed in suppressing the formation and development of pupae of Galleria mellonella, is noted. Essential oil reduces the percentage of pupated larvae and emitted adults 3 times and the mass of larvae 40.7-48.0% when compared with the control. [ABSTRACT FROM AUTHOR]

The house rat (Rattus rattus) is the most destructive commensal rodent pest causing severe damage to stored grains. Use of natural products as aversive agents against rodent pests can be a safe alternative to chemical pesticides. In the present study, the potential of 2% red chilli powder and 0.3% capsicum oleoresin (containing capsaicin as active ingredient) as aversive agents was evaluated against R. rattus of both the sexes under simulated store conditions. Results showed that both red chilli powder and capsicum oleoresin applied as spray on jute bags containing wheat grains prevented rodent damage to bags and grains in terms of reduced number of cuts to bags, spillage of grains and consumption of grains by rats. Study suggests the use of red chilli powder and capsicum oleoresin sprays on bags as a method to be integrated with rodenticide usage. [ABSTRACT FROM AUTHOR]

Abstract: Plants are sources of numerous active substances that are used to protect crops. Currently, due to the limitations of using synthetic insecticides, plant products have attracted increasing attention as possible pesticides. In this review, we discuss some of the most interesting plant products (for example, Solanaceae, or Asteraceae extracts, Artemisia absinthium or Citrus spp. essential oils, and single compounds like α‐chaconine, or α‐solanine) that exhibit insecticidal activity against beetles that are pests of stored food products. Next, we describe and discuss the mode of action of these products, including lethal and sublethal effects, such as antifeedant or neurotoxic activity, ultrastructural malformation, and effects on prooxidant/antioxidant balance. Furthermore, the methods of application of plant‐derived substances in food storage areas are presented. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The antifeedant activity of 18 sesquiterpenoids of the drimane family (polygodial, drimenol and derivatives) was investigated. RESULTS: Polygodial, drimanic and nordrimanic derivatives were found to exert antifeedant effects against two insect species, Spodoptera frugiperda and Epilachna paenulata, which are pests of agronomic interest, indicating that they have potential as biopesticide agents. Among the 18 compounds tested, the epoxynordrimane compound (11) and isonordrimenone (4) showed the highest activity [50% effective concentration (EC50) = 23.28 and 25.63 nmol cm−2, respectively, against S. frugiperda, and 50.50 and 59.00 nmol/cm2, respectively, against E. paenulata]. CONCLUSION: The results suggest that drimanic compounds have potential as new agents against S. frugiperda and E. paenulata. A quantitative structure–activity relationship (QSAR) analysis of the whole series, supported by electronic studies, suggested that drimanic compounds have structural features necessary for increasing antifeedant activity, namely a C‐9 carbonyl group and an epoxide at C‐8 and C‐9. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The need for the development of alternative types of selective control methods for crop protection with reduced use of chemical pesticides was the main objective of this present review article. This review is based on earlier works performed by many investigators on insecticidal and acaricidal property of bioactive components derived from Piper longum. The summarization of all recent works on application of phytochemicals associated with P. longum in insect pests control may be an alternative to currently used chemical pesticides for development of target specific, biodegradable into nontoxic products, safer and potentially suitable to use in integrated pests management programmes. [ABSTRACT FROM AUTHOR]

Unraveling the relationship between the unusual feeding behaviors and the nutritional intake of endangered species may provide crucial information for understanding species response to habitat unpredictable changes. Primates occasionally re‐ingest fruit seeds alongside ingestion of feces, a behavior called coprophagy. The nutritional benefit is one of the several non‐mutual exclusive hypotheses proposed to explain this behavior. We investigated the ecological correlates of coprophagy in wild western gorillas. We tested whether coprophagy occurred during periods of lower fruit availability and whether it led to higher nutrient intake in comparison to the other food. Data integrated phenological, fecal and nutritional analyses of gorilla food with behavioral observations collected at two sites in Central Africa (Mbeli Bai: ad libitum observations on 15 groups/solitary males, October 2002–November 2005; Bai Hokou: 5‐min scan on a habituated group, December 2004–December 2005). Coprophagy occurred at the end of the high‐fruiting season in association of two Dialium species. Coprophagy correlated positively with the occurrence of Dialium spp. fruit in gorilla feces and in the feeding scans, and showed a positive trend with Dialium availability but not with total fruit availability. Nutritional comparison of Dialium seeds with other important gorilla food showed higher fat and mineral content, particularly of Mg, but also of phenols and tannins in Dialium seeds. We discuss how the effect of gut processing and gut heat via coprophagy may act as cooking‐like effect: increasing the ability to maximize nutrient intake by concurrently softening fibers and decreasing the toxic effect of antifeedants, like in human traditional cooking. Our results support both the multiple nutritional benefit hypothesis and the toxicity reduction hypothesis. Since Dialium is precious timber, the importance of this tree for the critically endangered western gorillas should be taken with high consideration when planning controlled logging of degraded forests or in face of habitat changes. [ABSTRACT FROM AUTHOR]

Objective: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora (Syn. Cassia tora) against cowpea weevil (Callosobruchus maculatus). Methods: The activities were evaluated using standard protocols. In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 µg/mL and compared to neem oil and cinnamaldehyde (as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2D-NMR and ESI-MS studies. Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone, aurantio-obtusin (1) and a novel compound that was named as cassiatorin (2). Compounds 1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls. Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds (1 and 2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants. [ABSTRACT FROM AUTHOR]