Alternative Pesticides Research Articles

The Environmentally Benign form of Pesticide in Hydrodispersive Nanometric form with Improved Efficacy Against Adult Mosquitoes at Low Exposure Concentrations.

Permethrin, a poorly water-soluble synthetic pesticide belonging to the pyrethroid family, was formulated into water-dispersive nanometric form by rapid evaporation of pesticide loaded oil-in-water microemulsion. The mean hydrodynamic diameter of Nanopermethrin was found to be 199.01±1.4nm. The efficacy of the Nanopermethrin was comparatively investigated with its bulk form against 2-3days old adult mosquitoes by WHO cone bioassay for 60min. The median knockdown concentration of Culex tritaeniorhynchus, Culex quinquefasciatus and Aedes albopictus were found to be 7.20×10(4), 7.53×10(4), 0.42×10(3)mg/L for Bulk permethrin, and 0.98×10(4), 1.17×10(4), 0.05×10(3)mg/L for Nanopermethrin, respectively. The obtained results extrapolate the improved efficacy of Nanopermethrin even at low-level concentrations. Hence, the formulated Nanopermethrin will serve as an effective alternative pesticide in controlling the mosquito population with reduced environmental toxicity.

Characterization of volatile compounds from three Cymbopogon species and Eucalyptus citriodora from Benin and their insecticidal activities against Tribolium castaneum

The chemical volatile profiles of four plant species from Benin were established via SDE/GC–MS and SPME/GC–MS, and were compared to chemical profiles obtained by hydrodistillation/GC–MS. Essential oils and selected identified compounds were used to perform fumigant tests and contact “no choice” tests against adults of the red flour beetle Tribolium castaneum, an important pest insect in stored products worldwide. The chemical profiles and the concentrations of the main compounds varied with the method used. Geranial (hydrodistillation, SPME) and geraniol (SDE) for Cymbopogon citratus, piperitone for Cymbopogon schoenanthus (hydrodistillation, SPME, SDE), E-p-mentha-1(7), 8-dien-2-ol for Cymbopogon giganteus (hydrodistillation, SPME, SDE), neo-isopulegol (SDE) and citronellal (hydrodistillation and SPME) for Eucalyptus citriodora, were identified as main volatile compounds. By fumigation, the LC50 values obtained after 24h for essential oils of C. citratus, C. giganteus, C. schoenanthus, E. citriodora, and for piperitone and citronellal were 4.2mL/L air, 2.3mL/L air, 2.1mL/L air, 2.0mL/L air, 0.5mL/L air and 1.2mL/L air, respectively. Furthermore, mortalities of 100%, 82%, 75%, 72%, 68% and 42%, respectively, were found for piperitone at 2.4mL/L air, citronellal at 2.1mL/L air, and essential oil extracted from E. citriodora, C. schoenanthus, C. giganteus and C. citratus, at 4mL/L air. By contact “no choice” test, the LC50 values for the crude oils after 72h were: 15% (w/v), 6% (w/v), 6% (w/v) and 5% (w/v) for C. citratus, C. giganteus, C. schoenanthus and E. citriodora, respectively. After 72hours, mortalities of 18%, 67%, 73%, 82%, 87% and 40% for essentials oils (8% w/v) of C. citratus, C. giganteus, C. schoenanthus, E. citriodora, piperitone at 4.7% w/v, and citronellal at 4.2% w/v, respectively, were obtained. The essential oil from C. schoenanthus and E. citriodora as well as piperitone and citronellal represent potential valuable alternative pesticides to conquer the resistance of T. castaneum to synthetic insecticides.

Analysis of the Time-Concentration-Mortality Response of Nilaparvata lugens (Hemiptera: Delphacidae) to Paichongding.

Paichongding is an adicyclicnitromethylene neonicotinoid insecticide with a cis-configuration. Bioassay of paichongding was conducted against Nilaparvata lugens Stål under a laboratory condition. Mortality of N. lugens was analyzed by time-concentration-mortality (TCM) regressions based on the complementary log-log (CLL) model. The conditional mortalities of test individuals increased with the exposure time after treatments with different concentrations, showing that the speed of insecticidal action is concentration dependent. Meanwhile, the conditional mortalities of N. lugens increased as the concentrations of paichongding increased for all developmental stages from instars I-II to macropterous females. Correspondingly, LC(50) and LC90 values to N. lugens gradually decreased with the developmental stages, in which instars I-II were the most sensitive to paichongding, with LC(50) values of 6.31, 0.45, 0.09, and 0.03 mg/liter for 24, 48, 72, and 96 h after treatments, respectively, while macropterous females were the least sensitive among all developmental stages, with LC(50) values of 309.03, 11.48, 1.35, and 0.19 mg/liter at 24, 48, 72, and 96 h after the treatments, respectively. The time-concentration-mortality modeling was mathematically and biologically robust to evaluate the effects of paichongding on N. lugens. The results suggest that paichongding would be an effective alternative pesticide for controlling N. lugens considering its potent effects.

Biological activities of Cuminum cyminum seed oil and its major components against Callosobruchus chinensis and Sitophilus oryzae

The study reports the fumigant, repellent, oviposition deterrent, ovicidal, larvicidal and pupaecidal activities of Cuminum cyminum seed essential oil and its 4 main components (cymene, γ-terpinene, cuminaldehyde and (−)-β-pinene) against Callosobruchus chinensis and Sitophilus oryzae. The essential oil, γ-terpinene and (−)-β-pinene showed pronounced activity in all parameters against both the insects. However, the susceptibility of C. chinensis was much higher than S. oryzae. Cymene and cuminaldehyde showed poor mortality to insects but caused moderate repellency and oviposition deterrency at 100μl/L air. The essential oil when tested for practical application in protection of food commodities from insect infestation in storage containers, exhibited 100% and 97% feeding deterrent index at 100μl/L air concentration against C. chinensis and S. oryzae damage respectively without affecting viability of chickpea and wheat. C. cyminum seed essential oil may thus be recommended as eco-friendly and biorational alternatives of synthetic pesticides for management of insect infestation of food commodities.

딸기 주요 병원균에 대한 친환경제제 NaDCC의 항균활성 및 병 방제효과 평가

딸기에는 여러 가지 병이 발생하여 경제적으로 막대한 손실을 유발하며 많은 양의 농약이 사용되고 있는 실정이다. 최근 유기농산물과 식품안전성에 관한 소비자의 관심이 증가함에 따라 화학농약 대체제에 의한 병해 방제법 개발이 다각적으로 시도되고 있다. 본 연구에서는 광범위 소독제로 사용하고 있는 NaDCC의 딸기 주요 병원균(딸기 시들음병, 딸기 탄저병, 딸기 역병 그리고 딸기 세균성모무늬병)에 대한 항균활성 및 방제효과를 검증하고, 친환경제제로의 가능성을 확인하고자 수행되었다. NaDCC는 150~300 ppm 농도로 처리했을 때 병원진균의 균사생장을 효과적으로 억제하였고, 포자 발아율도 68% 이상 경감시키는 것으로 조사되었다. NaDCC는 딸기 세균성모무늬 병원균에 대하여서도 우수한 방제효과를 나타내었는데, 포장조건에서 딸기 세균성 모무늬병의 발생을 50% 감소시키는 것으로 나타났다. 이상의 결과를 토대로 NADCC는 딸기 병 방제용 방제제 후보물질로 사용될 수 있을 것으로 생각되었다. Various diseases occur in fruits, leave and roots during strawberry cultivation and cause severe economical damage and huge amount of chemical fungicide use. Recently, as consumers' interest in safety of foods and organic agriculture produces have increased, control measures using alternatives for chemical fungicides have been newly developed in various ways. This study was conducted to test antifungal activity and control effect of sodium dichloroisocyanurate (NaDCC), using as disinfectants, against major disease pathogens of strawberry, Fusarium oxysporum (Fusarium wilt), Colletotrichum gloeosporioides (Anthracnose) and Phytophthora sp. (Phytophthora blight), and Xanthomonas fragariae (bacterial angular leaf spot) and evaluate availability as environment-friendly materials. When NaDCC was treated at the concentration range of 150 to 300 ppm, it suppressed significantly hyphal growth and reduced spore germination by more than 28%. In field condition, NaDCC showed excellent control effect (control value: 50%) against the bacterial angular leaf spot disease. Based on above-described results, we suggested that NaDCC can be used as alternative candidates to chemical pesticide alternatives of for controlling strawberry diseases.

Growth Inhibition of Grain Spoilage Fungi by Selected Herbs and Spices Essential Oils

Natural plant extracts are promising alternatives for chemical food additives and synthetic pesticides. In this study, essential oils of selected herbs and spices were tested for their antimicrobial activities against Aspergillus flavus and Aspergillus niger, two of the most common food spoilage microorganisms. Agar disk diffusion assay was used for screening of the most effective essential oils, agar dilution assay was used to determine Minimum Inhibitory Concentration (MIC) of the essential oils and broth dilution assay was employed to the spore germination inhibition assay. Tests were also conducted to examine the effects of the essential oils for sorghum kernel protection against the tested fungi, and the optimal protective dosages on the sorghum grains were also determined. From the preliminary tests, essential oils of Cinnamomum zeylanicum (Cinnamon) and Thymus schimperi (thymus) were found to be the most effective. However piper nigrum (black pepper) had no effect on the test organisms. In MIC, spore germination inhibition and grain protection assay, cinnamon essential oil was found to be superior where its MIC on the isolates was found to be 0.0156% and its optimum protective dosage on the sorghum grain was 5%. It inhibited spore germination at a concentration of 3iL/mL. The effect of thymus oil was also very much comparable to these results (no significant difference at P>0.05). Finally, it was concluded that essential oil extracts of cinnamon and thymus can be a useful source of antifungal agents for protection of grain spoilage by fungi.

Nanoparticles as Alternative Pesticides: Concept, Manufacturing and Activities

Nanotechnology, which has become an important area of science, has caused an enormous developmental revolution in many fields. In the last two decades researchers have focused on overcoming the obstacles encountered during the preparation of nanoparticles. This article highlights the nanotechnology, along with a brief description of the manufacturing, concepts and activities of nanoparticles as alternative pesticides against plant pathogens, some methods for evaluation of nanoparticles against phytopathogens in vitro and in vivo, and explains the importance of some common nanoparticle types used in agricultural applications and plant pathology.

Quantitative Analysis of Cinnamaldehyde, Cinnamylalcohol and Salicylaldehyde in Commercial Biopesticides Containing Cinnamon Extract Using Gas Chromatography - Flame Ionization Detector

BACKGROUND: In an environment-friendly agriculture, plant extracts have been perceived as alternatives of synthetic pesticides. The Environment-friendly Agriculture Promotion Act of Korea has approved cinnamon extract as a matter for the production of commercial biopesticides. Thirteen commercial biopesticides containing cinnamon extract have been marketed locally. However, the analytical method for the quality control of these biopesticides containing cinnamon extract has not been studied. METHODS AND RESULTS: Cartridge clean-up method for the determination of cinnamaldehyde, cinnamylalcohol and salicylaldehyde in biopesticides containing cinnamon extract was developed and validated by gas chromatography (GC). The clean-up method was optimized with HLB SPE cartridges for the bioactive substance in biopesticides containing cinnamon extract, and the eluate was analyzed by GC. The developed method was validated, and the LOQ and recovery rates of cinnamaldehyde, cinnamylalcohol and salicylaldehyde were 0.139, 0.067 and and 84.2, 86.5 and 82.1%, respectively. The contents of cinnamaldehyde, cinnamylalcohol and salicylaldehyde were analyzed using the developed method in the 13 commercial biopesticides. Results showed 0.06-17.37%,

Biofumigation effect of <i>Brassica napus</i> on soil microbial communities

Biofumigation effect of Brassica napus on soil microbial communities Due to their biofumigation potential, Brassica plant species incorporated into the soil can be applied as alternatives for chemical pesticides. However, little is known about the effect of such biofumigants on the natural soil microbial communities required to maintain soil functions.

Generation of Wood-waste Vinegar and Its Effectiveness as a Plant Growth Regulator and Pest Insect Repellent

Wood vinegar (WV) was obtained from charcoal production byproducts. The increase in demand for WV as an alternative pesticide requires more production of WV independent of conventional charcoal production. This research was intended to commence the production of WV from available furniture wood waste. The study included the following: (i) the preparation and performance of a pyrolysis kiln; and (ii) the application of the produced WV as a plant growth regulator of papaya plants in the nursery and as a pest insect repellent during maize storage. These experiments were arranged in a randomized block design. The observed variables included pyrolysis rate, the effect of WV on papaya growth in nursery, and the effect of WV in controlling infestation of maize weevils. The data were analyzed using analysis of variance and continued with Duncan’s multiple difference test. The results showed that while the production of WV continuously occurred until the 90th min, the maximum (139 mL) was reached at the 10th min. Pyrolysis of 1,000 g of chips of wood-planer’s waste yielded WV, tar, bio-oil, and char in quantities of 487.67 mL, 41.76 g, 2.93 mL, and 222 g respectively. The treatment using WV (50 mL/L) increased the diameter of papaya stems in the nursery. Mixing and fuming application of 5 mL of WV as a pest insect repellent on 200 g of maize on the storage could increase the number of the dead maize weevil and reduce the damage maize kernel.

When ignorance is not bliss: Pest control decisions involving beneficial insects

Recent survey data revealed that many California citrus growers did not know whether or not important beneficial insects were found on their fields while other growers were relying heavily or even entirely on these insects for pest control. Some pesticides are toxic both to the targeted pest and the predaceous or parasitic insect that could provide pest control. Alternative pesticides with fewer or no negative effects on the beneficial insect often exist but can be more expensive. Additionally, some beneficial insects are commercially available and can be purchased and released in the field. This paper models the pest control decisions of a grower who utilizes a pesticide and a predaceous insect to control the crop pest and compares these decisions to that of a grower who does not know that the predaceous insect exists. The results show that the latter grower will drive the predator population to zero and will overutilize chemical control. When the predator is known and utilized, the optimal decisions involve entirely mitigating the negative effects of the pesticide as well as releasing additional predators.

Phytochemicals, antioxidant and antifungal activities of Allium roseum var. grandiflorum subvar. typicum Regel.

The chemical composition of essential oil hydrodistillized from Allium roseum var. grandiflorum subvar. typicum Regel. leaves was analyzed by GC and GC/MS. Nine extracts obtained from flowers, stems and leaves and bulbs and bulblets of A. roseum var. grandiflorum were tested for their total phenol, total flavonoid and total flavonol content. All these extracts and the essential oils from fresh stems, leaves and flowers were screened for their possible antioxidant and antifungal properties. The results showed that the hexadecanoic acid was detected as the major component of the leaf essential oil (75.9%). The ethyl acetate extract of stems and leaves had the highest antioxidant activity with a 50% inhibition concentration (IC50) of 0.35±0.01mg/mL of DPPH and 0.71±0.01mg/mL of ABTS+. All the extracts appeared to be able to inhibit most of the tested fungi. The essential oil of the leaves had an antifungal growth effect on Fusarium solani f. sp. cucurbitae and Botrytis cinerea (39.13 and 52.50%, respectively). This could be attributed to the presence of hexadecanoic acid, known for its strong antifungal activity. In conclusion, in addition to the health benefits of A. roseum, it can be used as an alternative pesticide in the control of plant disease and in the protection of agriculture products.

HYPOTHETICAL PEAR PRODUCTION SYSTEM INNOVATION THROUGH PROMOTION OF SOIL BIODIVERSITY

We developed a hypothetical view on a pear production system innovation through promotion of soil biodiversity. Two types of measures form the central idea of the innovation. The first type of measure is to replace part of the current 100% mineral fertilisation by compost plus targeted use of specialised soil and leaf fertilisers. The second type of measure is to replace pesticides harmful for soil life by alternative measures or non-harmful pesticides. We anticipate that these measures would have three main effects. The first effect is improved soil life, the second is reduced environmental impacts, and the last is increased economic profit for the fruit grower.

The side effect of some pesticide alternatives on the population densities of the natural enemies of two piercing-sucking insect pests at the new valley province, Egypt

The side effect of some pesticide alternatives on the population densities of the natural enemies of two piercing-sucking insect pests at the new valley province, Egypt

English

Green house studies were conducted to determine the ability of plant Amaranth, Amaranthus caudate and two isolated bacterial strains from rhizosphere region for cleaning up glyphosate residues in soil and plants. The analytical study of the degradation of glyphosate was carried out in the laboratory conditions. Amaranth, Amaranthus caudate and two isolated bacterial strains namely Pseudomonas aeruginosa and Bacillus megaterium could degrade glyphosate in 5 days. These results suggested that phytoremediation could accelerate the degradation of glyphosate residues in plants and in rhizosphere region as well. Glyphosate had strong effect on bacterial DNA where many DNA bands were affected. This could be explained that the effect of herbicide glyphosate on the protein profile may reflex somehow DNA mutation occurred during the assimilation of those toxic compounds. Therefore, the alteration occurred in both DNA and protein profiles is considered a degree of tolerance that lead to DNA mutation to cope with the assimilation of this compound. Therefore, the phytoremediation way could be a promising tool in program is to protect public health and the environment by ensuring the safety and availability of herbicides and pesticide alternatives.

Botanicals as eco friendly biorational alternatives of synthetic pesticides against Callosobruchus spp. (Coleoptera: Bruchidae)-a review.

The article presents the potential of botanicals in the management of Callosobruchus spp., the primary insect pest causing deterioration to a variety of stored legume grains. Different botanical formulations have been reported time to time showing pronounced insecticidal activity, repellence to pest, oviposition deterrency, adult emergence inhibition, ovicidal, larvicidal, pupaecidal activity and feeding deterrency based on their contact toxicity and fumigation effects. Some of the botanicals have also been practically proved efficacious to protect the stored food commodities from the bruchids during storage conditions. Such botanical formulations have shown their promise in integrated management of the pest as semiochemicals by showing behaviour altering efficacy against the bruchids, thereby, reducing the induced pest resistance problem which is frequently reported with synthetic pesticides. Hence, they may be recommended in food security programmes as eco-friendly and biorational alternatives of synthetic pesticides providing integrated management of the losses of stored food commodities due to infestation of bruchids.

Temporal variation of residential pesticide use and comparison of two survey platforms: a longitudinal study among households with young children in Northern California

BackgroundPesticide use patterns are essential inputs into human pesticide exposure models. Currently, data included for modeling purposes have mostly been collected in cross-sectional surveys. However, it is questionable whether responses to one-time surveys are representative of pesticide use over longer periods, which is needed for assessment of health impact. This study was designed to evaluate population-wide temporal variations and within-household variations in reported residential pesticide use patterns and to compare alternative pesticide data collection methods – web surveys versus telephone interviews.MethodA total of 481 households in Northern California provided up to 3 annual telephone interviews on residential pesticide use; 182 of these households provided up to 6 quarterly web surveys that covered the same topics for some of the same time periods. Information on frequency and areas of application were collected for outdoor and indoor sprays, indoor foggers, professional applications, and behind-the-neck treatments for pets. Population-wide temporal variation and within-household consistency were examined both within telephone surveys and within web surveys, and quantified using Generalized Estimating Equations and Mixed Effect Modeling. Reporting between the two methods, the telephone survey and the web survey, was also compared.ResultsUse prevalence of outdoor sprays across the population reported in both the annual telephone surveys and the quarterly web surveys decreased over time, as did behind-the-neck treatment of pets reported in the quarterly web survey. Similarly, frequencies of use of these products decreased in the quarterly web surveys. Indoor sprays showed no statistically significant population-wide temporal variation in either survey. Intraclass correlation coefficients indicated consistent use within a household for behind-the-neck treatment on pets and outdoor sprays but great variability for the use of indoor sprays. Indoor sprays were most consistently applied in the bathroom and kitchen. Outdoor sprays were consistently more often applied by male household members, while indoor sprays were not. The two survey approaches obtained fairly similar results on the prevalence of using pesticides, but found discrepancies in use frequencies. In addition, the number of products purchased was positively correlated with application frequency for outdoor sprays (R = 0.51, p = 0.0005) but not for indoor sprays.ConclusionsIn this population, repeated surveys are necessary either to obtain a reliable estimate of the average household use of pesticides or to project potential temporal changes of pesticide use. Web surveys could collect comparable data to traditional telephone surveys for some information. However, researchers need to consider the internet acceptability among the target population and balance lower participant burden against the need for sufficiently accurate time-varying measurement, to improve subject retention in longitudinal surveys.

Plant Essential Oils Affect the Toxicities of Carbaryl and Permethrin Against <I>Aedes aegypti</I> (Diptera: Culicidae)

ABSTRACT Phytochemicals have been considered as alternatives for conventional pesticides because of their low mammalian toxicity and environmental safety. They usually display less potent insecticidal effects than synthetic compounds, but may express as yet unknown modes of action. In the current study, we evaluated 14 plant essential oils for their toxicities and synergistic effects with carbaryl and permethrin against fourth instars of Aedes aegypti (L.) as well as 5-7-d-old adults. Six essential oils showed significant synergistic effects with carbaryl at 10-50 mg/liter, but paradoxically all of them decreased the toxicity of permethrin against Ae. aegypti larvae. None showed toxicity or synergistic effects on Ae. aegypti adults, at doses up to 2,000 ng/ insect. The six essential oils displaying synergistic effects in Ae. aegypti larvae inhibited the in vitro activities of cytochrome P450 monooxygenases and carboxylesterases in the low milligram per liter range. The data indicated that cytochrome P450 monooxygenases and carboxylesterase were probably targets for these natural synergists. Thus, the mechanism of synergism was most likely inhibition of metabolism and not interacting target site effects.

Enhanced extraction of caffeine from guaraná seeds using aqueous solutions of ionic liquids

The extraction of caffeine from bioresources using more benign and cost-effective processes is of fundamental relevance towards the finding of alternative (bio)pesticides. Classically, the best attempts to extract caffeine from biomass have resulted in low efficiency and in a large consumption of hazardous organic solvents and/or energy requirements. Here, we report an enhanced and selective extraction of caffeine from guarana (Paullinia cupana, Sapindaceae) seeds using aqueous solutions of ionic liquids. Several ionic liquids composed of imidazolium or pyrrolidinium cations combined with the chloride, acetate and tosylate anions were investigated. Furthermore, the effect of the cation alkyl side chain length and the presence of functionalized groups were also addressed. Additional conditions such as the ionic liquid concentration, the contact time, the solid–liquid ratio and temperature were further optimized by a response surface methodology. Outstanding extraction yields (up to 9 wt% of caffeine per guarana dry weight) were obtained at a moderate temperature and in a short-time. The recyclability and reusability of the ionic liquids were also confirmed. For the first time it is shown that aqueous solutions of ionic liquids are superior alternatives for the solid–liquid extraction of caffeine from biomass samples and, as a result, the development of an ionic-liquid-based process is straightforwardly envisaged.

Insecticidal activities of five plant derived chemicals on Thrips tabaci Lindeman

Background: Natural compounds originating from plants might be potential alternative pesticide that are not persistent in the environment and are safe to non-target organisms and for use in sustainable agriculture. Methods: Ethanolic extracts (30 μl/mL) of Melia azedarach L. (Fruits), Peganum harmala L. (seeds) , Calendula offi cinalis L. (seeds) , Ferula assafoetida L. (resin) and Cercis siliquastrum L. (seeds) were applied against 1-2 and 5-6 days of Thrips tabaci Lindeman. All the experiments were conducted by spray test bioassay. Ethanol (95%) was used as a control treatment. Results: All the plant derived chemicals were highly toxic against the pre-imago thrips. The mortality percentages of the pest (1-2day old) after 72 hours were more than 66.0% in each of the plant extracts. The highest insecticidal activity against the above-mentioned pre-imago thrips was recorded for the F. assafoetida treatment (96.7%). Insecticidal activity was more than 85% in the ethanolic extract M. azedarach and P. harmala treatments. Moreover, the mortality percentage of the thrips (5-6-day old) after 72 hours was more than 80.6% in the ethanolic extract of F. assafoetida treatment. Conclusions: The plant derived chemicals tested in this study may be useful as a insecticide in T. tabaci management programs, although their safety towards humans needs verifi cation.