Pyrethrum Research Articles

Chinese star anise (Illicium verum) and pyrethrum (Chrysanthemum cinerariifolium) as natural alternatives for organic farming and health care- A review

Botanical insecticides keep attracting more attention from environmental and small farmers worldwide as they are considered as a suitable alternative to synthetic insecticides. The outstanding properties of pyrethrum include rapid action, low mammalian toxicity, broad spectrum of activity, lack of insect immunity, lack of persistence and of course effective insect repellent. Pyrethrum is a natural insecticide which has many properties, but the most important are rapid action, very low toxicity for mammalian, lack of insect immunity, broad of activity, lack of persistence and quick degradation by UV-sunlight and very effective insect repellent. Using natural pesticide may lead to organic farming, and advantage of organic farming is more beneficial to biodiversity and the environment, which reduces dietary exposure to pesticides. Chinese star anise has anti-bacterial and anti-fungal characters. It is useful in treatment of diseases like asthma, bronchitis and dry cough. One of its most compounds is Shikimic acid which is used as a drug in curing influenza and flu virus. It also consists of Linalool which is good for overall health because of its anti-oxidants characters. Its seeds are good source of minerals like calcium, iron, copper, potassium, manganese, zinc, and magnesium. The seeds are a great source of essential B-complex vitamins such as pyridoxine, niacin, riboflavin and thiamin. Chinese star anise is also a good source of anti-oxidant vitamins such as vitamin-C and vitamin-A. The essential oil of Star anise contains anethole which has shown several functional properties including antimicrobial, antioxidant, hypoglycemic, hypolipidemic and oestrogenic properties. Star anise primarily contains anethole and fatty oil. Its essential oil has a sweetish, burning flavor and a highly aromatic odor. Organic farmers may use these two ancient Chinese herbs which can lead to industrial sustainability.

Draft genome of Tanacetum cinerariifolium, the natural source of mosquito coil

Pyrethrum (Tanacetum cinerariifolium), which is a perennial Asteraceae plant with white daisy-like flowers, is the original source of mosquito coils and is known for the biosynthesis of the pyrethrin class of natural insecticides. However, the molecular basis of the production of pyrethrins by T. cinerariifolium has yet to be fully elucidated. Here, we present the 7.1-Gb draft genome of T. cinerariifolium, consisting of 2,016,451 scaffolds and 60,080 genes predicted with high confidence. Notably, analyses of transposable elements (TEs) indicated that TEs occupy 33.84% of the genome sequence. Furthermore, TEs of the sire and oryco clades were found to be enriched in the T. cinerariifolium-specific evolutionary lineage, occupying a total of 13% of the genome sequence, a proportion approximately 8-fold higher than that in other plants. InterProScan analysis demonstrated that biodefense-related toxic proteins (e.g., ribosome inactivating proteins), signal transduction-related proteins (e.g., histidine kinases), and metabolic enzymes (e.g., lipoxygenases, acyl-CoA dehydrogenases/oxygenases, and P450s) are also highly enriched in the T. cinerariifolium genome. Molecular phylogenetic analysis detected a variety of enzymes with genus-specific multiplication, including both common enzymes and others that appear to be specific to pyrethrin biosynthesis. Together, these data identify possible novel components of the pyrethrin biosynthesis pathway and provide new insights into the unique genomic features of T. cinerariifolium.

Uncovering Potential of Neem and Pyrethrum Extract as Biolarvacide of Aedes aegypti for Dengue Control

Currently, several problems raised from the frequent application of chemical insecticide for dengue control such as insecticide resistance and environmental health issues. This fact supporting the need for the alternative active ingredients which are natural and could not develop insecticide resistance. This study aims to find out the potential of Pyrethrum (Chrysanthemum cinerariifolium (Trevir.) Vi) and Neem (Azadirachta indica A. Juss) as biolarvacide against Aedes aegypti. This study used a quasi-experimental study using several combinations of Pyrethrum and Neem extracts. The larvae test used 25 larvae for every combination. Three repetitions applied for each treatment. Larval deaths were observed every hour until 24 hours, and several dead larvae were calculated. Results of this study showed that almost all formulations caused death of larvae in the first hour except formulation 5 (2 ml Pyrethrum + 1 ml DMSO + 24 ml liquid paraffin + 24 ml chitin), formulation 8 (49 ml neem + 1 ml Tween 20) and formulation 11 (49 ml neem + 1 ml DMSO). These results emphasised the potential of a formulation containing Pyrethrum and neem as biolarvacide against Aedes aegypti…. (Introduction, methods, results, discussion, conclusion)

Matrix solid-phase dispersion optimization for determination of pyrethrin content in Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.) by liquid chromatography

The mixture of six components (pyrethrin I and II, cinerin I and II, and jasmolin I and II) constituting natural insecticide pyrethrin is responsible for the insecticidal activity of Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.). In order to obtain deeper knowledge of its insecticidal potential, the extraction of mentioned components from plant samples was carried out for the first time, by matrix solid-phase dispersion. The influence of different factors such as the type of sorbent, sorbent-sample ratio, the elution solvent and its volume, addition of co-sorbent and drying agent, affecting extraction yield was evaluated. The pyrethrin components were extracted under optimized conditions: florisil (0.5 g) as the sorbent, mixed with 0.25 g of pyrethrum flower heads, 5 mL of acetone-ethyl acetate (1:1, v/v) as the elution solvent and 0.4 g of Na2SO4 as the drying agent. All six components in the extracts were qualitatively and quantitatively determined by HPLC-DAD. Analytical method provides high degree of linearity with r2≻0.9974, except for pyrethrin II (0.9961). Also, the method showed good precision (intra- and inter-day) with a relative standard deviation below 14 %, and recoveries mainly above 80 %. In order to demonstrate the applicability of the developed method, three Dalmatian pyrethrum natural populations from Croatia were analyzed.

Pyrethrin Biosynthesis: From a Phytohormone to Specialized Metabolite.

Dalmatian chrysanthemum ( Tanacetum cinerariifolium ) contains pyrethrins, which are highly effective natural insecticides that are nontoxic to most animals and biodegradable. Purification of these natural compounds, however, is more costly than production of their synthetic analogs, although the

ANTICANCER ACTIVITIES AND METABOLITE FINGERPRINTING OF UPLC-QToF-MS/MS METHOD FROM Chrysanthemum cinerariifolium (Trev)

<p><em>Chrysanthemum cinerariifolium</em> (<em>C. cinerariifolium</em>) is an empirically proven medicinal plant that has anticancer activities. This study aimed to profile metabolites, and cytotoxic activity of root, leaf, stem, and root extracts <em>C. cinerariifolium</em> on T47D cells and to determine the correlation of metabolite content with cytotoxic activity. The metabolite profile was carried out using UPLC-QToF-MS / MS, and cytotoxic activity was carried out using the MTT method. The results obtained in the form of a chromatogram were processed with the application <em>Masslynk</em> so that a metabolite profile data obtained. The data is then analyzed statistically using <em>Principal Component Analysis</em> (PCA). The results obtained on metabolite profiling showed that there were differences in metabolite profiles in the roots, stems, leaves, and chrysanthemums. The characteristic compounds in the flower section are <em>D - (-) - Morphine</em> and in the leaf part of <em>genistein </em> and <em>N - [(5-Chloro-1,2,3-thiadiazol-4-yl) methyl] -1- (2-isopropyl-4 -methyl-1,3-thiazol-5-yl) -N-methyl ethanolamine</em>. The major compounds in the roots, stems, and leaves are <em>Orphenadrine</em> with successive percentages of 9.11%, 10.16%, and 3.24%, and the major compounds in the flower section are <em>D - (-) - Morphine</em> with a percentage of 10, 86%. Furthermore, the results of the cytotoxic activity test showed differences in anticancer cytotoxic activity in the parts of the flower, leaf, stem, and root of <em>C. cinerariifolium</em>. Besides, there is a relationship between the metabolite content and anticancer cytotoxic activity of each part of <em>C. cinerariifolium</em>. The higher the level of orphenadrine compounds in the plant, the higher the potential for anticancer.</p><p> <strong>Keywords</strong>: <em>C. cinerariifolium</em>, UPLC-QToF-MS/MS, T47D cells.</p>

GERMINATION OF TANACETUM CINERARIIFOLIUM SEEDS ON DIFFERENT SOIL TYPES

Tanacetum cinerariifolium (Trevir.) Sch. Bip. is a species of great economic importance because it contains Pyrethrins – natural insecticides with the potential to be the ideal means for pest control. Soil samples from different soil types (Skeletic Fluvisols, Rendzic Leptosol, Luvic Chernozem, Chromic Luvisols, Dystric-Eutric Cambisol, Pellic Vertisols) have been studied in order to determine the physicochemical soil indicators and the regressions between the soil characteristics and seed germination. Four hundred seeds (4х100) were planted in each soil type (in pots) under controlled conditions. Reliable statistically significant regressions, both negative (bulk density, sand fraction, available phosphorus) and positive (total porosity, silt and clay fractions, pH(H2O), CaCO3, Total Kjeldahl Nitrogen, Soil Organic Mater) with regard to seed germination have been established. The seeds planted in Rendzic Leptosol have shown the highest germination percentage, and the ones planted in Skeletic Fluvisols have shown the lowest germination percentage. Key words: Pyrethrum cinerariifolium Trev., Chrysanthemum cinerariifolium Bocc, seed germination, soil.

Pyrethrin Biosynthesis: The Cytochrome P450 Oxidoreductase CYP82Q3 Converts Jasmolone To Pyrethrolone.

The plant pyrethrum (Tanacetum cinerariifolium) synthesizes highly effective natural pesticides known as pyrethrins. Pyrethrins are esters consisting of an irregular monoterpenoid acid and an alcohol derived from jasmonic acid (JA). These alcohols, referred to as rethrolones, can be jasmolone, pyrethrolone, or cinerolone. We recently showed that jasmolone is synthesized from jasmone, a degradation product of JA, in a single hydroxylation step catalyzed by jasmone hydroxylase (TcJMH). TcJMH belongs to the CYP71 clade of the cytochrome P450 oxidoreductase family. Here, we used coexpression analysis, heterologous gene expression, and in vitro biochemical assays to identify the enzyme responsible for conversion of jasmolone to pyrethrolone. A further T cinerariifolium cytochrome P450 family member, CYP82Q3 (designated Pyrethrolone Synthase; TcPYS), appeared to catalyze the direct desaturation of the C1-C2 bond in the pentyl side chain of jasmolone to produce pyrethrolone. TcPYS is highly expressed in the trichomes of the ovaries in pyrethrum flowers, similar to TcJMH and other T cinerariifolium genes involved in JA biosynthesis. Thus, as previously shown for biosynthesis of the monoterpenoid acid moiety of pyrethrins, rethrolones are synthesized in the trichomes. However, the final assembly of pyrethrins occurs in the developing achenes. Our data provide further insight into pyrethrin biosynthesis, which could ultimately be harnessed to produce this natural pesticide in a heterologous system.

Population Structure of Colletotrichum tanaceti in Australian Pyrethrum Reveals High Evolutionary Potential.

Colletotrichum tanaceti, the causal agent of anthracnose, is an emerging pathogen of commercially grown pyrethrum (Tanacetum cinerariifolium) in Australia. A microsatellite marker library was developed to understand the spatio-genetic structure over three sampled years and across two regions where pyrethrum is cultivated in Australia. Results indicated that C. tanaceti was highly diverse with a mixed reproductive mode; comprising both sexual and clonal reproduction. Sexual reproduction of C. tanaceti was more prevalent in Tasmania than in Victoria. Little differentiation was observed among field populations likely due to isolation by colonization but most of the genetic variation was occurring within populations. C. tanaceti was likely to have had a long-distance gene and genotype flow among distant populations within a state and between states. Anthropogenic transmission of propagules and wind dispersal of ascospores are the most probable mechanisms of long-distance dispersal of C. tanaceti. Evaluation of putative population histories suggested that C. tanaceti most likely originated in Tasmania and expanded from an unidentified host onto pyrethrum. Victoria was later invaded by the Tasmanian population. With the mixed mode of reproduction and possible long-distance gene flow, C. tanaceti is likely to have a high evolutionary potential and thereby has ability to adapt to management practices in the future.

Anti-feedant activity of selected botanical extracts and their combinations on Plutella xylostella larvae

Many insect pests including the diamondback moth (Plutella xylostella L.) which has a known history of developing resistance to many pesticides, are believed to be able to develop that resistance as a result of a continuous and repeated use of pesticides with similar modes of action and or active ingredients. In nature however, plants would have been extinct; but plants produce compounds with toxicity to a wide variety of potential herbivores (Bush et al., 1997). Plants under attack release a cocktail of volatile compounds that act as cues for these allies, which then attack, consume and reduce the populations of herbivores (De Moraes et al., 1998). The aim of this study was to evaluate and compare the feeding and anti-feeding effects of Azadirachta indica, Chrysanthemum cinerariifolium and Quassia amara extracts (Azadirachtin, Pyrethrin and Quassin, respectively) and their mixtures on diamondback moth larvae. Larvae were fed with cabbage leaf disks treated with the various extracts. Mortality and leaf area consumed by larvae were recorded after 24 h of larval exposure to the treated leaves. Results revealed varying level of feeding and anti-feedant effects among all the formulations. Formulations with the highest concentration resulted in an increased feeding and anti-feedant effect in terms of larval mortality and feeding area. The most effective anti-feedant effect was recorded by the Pyrethrin, and Azadirachtin + Pyrethrin mixture (with a 1.0% feeding area each), followed by Azadirachtin + Pyrethrin + Quassin mixture and Pyrethrin + Quassin mixture with 2 and 3% feeding area, respectively. Pyrethrin, Azadirachtin + Pyrethrin and Azadirachtin + Pyrethrin + Quassin extracts combinations on the other hand recorded 50, 40 and 50% total larval mortality, respectively.

The Repetitive DNA Composition in the Natural Pesticide Producer Tanacetum cinerariifolium: Interindividual Variation of Subtelomeric Tandem Repeats

Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.), a plant species endemic to the east Adriatic coast, is used worldwide for production of the organic insecticide, pyrethrin. Most studies concerning Dalmatian pyrethrum have focused on its morphological and biochemical traits relevant for breeding. However, little is known about the chromosomal evolution and genome organization of this species. Our study aims are to identify, classify, and characterize repetitive DNA in the T. cinerariifolium genome using clustering analysis of a low coverage genomic dataset. Repetitive DNA represents about 71.63% of the genome. T. cinerariifolium exhibits linked 5S and 35S rDNA configuration (L-type). FISH reveals amplification of interstitial telomeric repeats (ITRs) in T. cinerariifolium. Of the three newly identified satellite DNA families, TcSAT1 and TcSAT2 are located subterminally on most of T. cinerariifolium chromosomes, while TcSAT3 family is located intercalary within the longer arm of two chromosome pairs. FISH reveals high levels of polymorphism of the TcSAT1 and TcSAT2 sites by comparative screening of 28 individuals. TcSAT2 is more variable than TcSAT1 regarding the number and position of FISH signals. Altogether, our data highlights the dynamic nature of DNA sequences associated with subtelomeres in T. cinerariifolium and suggests that subtelomeres represent one of the most dynamic and rapidly evolving regions in eukaryotic genomes.

Pyrethric acid of natural pyrethrin insecticide: complete pathway elucidation and reconstitution in Nicotiana benthamiana.

In the natural pesticides known as pyrethrins, which are esters produced in flowers of Tanacetum cinerariifolium (Asteraceae), the monoterpenoid acyl moiety is pyrethric acid or chrysanthemic acid. We show here that pyrethric acid is produced from chrysanthemol in six steps catalyzed by four enzymes, the first five steps occurring in the trichomes covering the ovaries and the last one occurring inside the ovary tissues. Three steps involve the successive oxidation of carbon 10 (C10) to a carboxylic group by TcCHH, a cytochrome P450 oxidoreductase. Two other steps involve the successive oxidation of the hydroxylated carbon 1 to give a carboxylic group by TcADH2 and TcALDH1, the same enzymes that catalyze these reactions in the formation of chrysanthemic acid. The ultimate result of the actions of these three enzymes is the formation of 10-carboxychrysanthemic acid in the trichomes. Finally, the carboxyl group at C10 is methylated by TcCCMT, a member of the SABATH methyltransferase family, to give pyrethric acid. This reaction occurs mostly in the ovaries. Expression in N.benthamiana plants of all four genes encoding aforementioned enzymes, together with TcCDS, a gene that encodes an enzyme that catalyzes the formation of chrysanthemol, led to the production of pyrethric acid.

Ray blight of pyrethrum in Australia: a review of the current status and future opportunities

Ray blight caused by Stagonosporopsis tanaceti is one of the most important diseases of pyrethrum (Tanacetum cinerariifolium), a perennial herbaceous plant cultivated for the extraction of insecticidal pyrethrins in Australia. The disease is responsible for complete yield loss in severe outbreaks. Infected seed is considered as the principal source of S. tanaceti. Infection hyphae remain only in the seed coat and not in the embryo, resulting in pre‐ and post‐emergence death of seedlings and latent infection. Therefore, quantification of the level of infection by S. tanaceti within seed using a qPCR assay is important for efficient management of the disease. Stagonosporopsis tanaceti completes its life cycle within 12 days after leaf infection through production of pycnidia and can infect every tissue of the pyrethrum plant except the vascular and root tissues. Ray blight epidemics occur in pyrethrum fields through splash dispersal of pycnidiospores between adjacent plants. Besides steam sterilization, thiabendazole/thiram and fludioxonil are effective seed‐treating chemicals in controlling S. tanaceti before planting begins. Ray blight is currently managed in the field through the foliar application of strobilurin fungicides in the first 1–2 years of crop establishment. Later on, difenoconazole and multisite specific fungicides in the next 2–3 years during early spring successfully reduce ray blight infestation. Avoiding development of resistance to fungicides will require more sustainable management of ray blight including the development and deployment of resistant cultivars.

Study of essential oil composition of Pyrethrum pulchrum Ledeb.

Pyrethrum pulchrum an impressive flower growing on large-stoned screes at the snow line, usually on glacier moraines in the mountains of Central Asia and South Siberia. The purpose of this study was to determine the essential oil composition from the aerial part of Pyrethrum pulchrum growing in Mongolia. The essential oil was obtained by hydro distillation and it had yield determined 0.1%. The oil was analyzed by GC-MS techniques. Fifty-seven components were identified representing 99.98% of the total oil composition. The main compounds of essential oil were camphor (33.9%), linalool (21.1%), α-pinene (9.0%), (Z)-γ-Curcumyl 2-methylbutyrate (4.82%), pentylcurcumene (3.21%), camphene (2.85%), tricosane (2.78%), nerolidol (2.63%), α-selinene (1.8%) and β-penine (1.4%). To our best knowledge, no previous studies have been reported on the chemical composition of the essential oil of Pyrethrum pulchrum.
 Дэгжин шиваантиг (Pyrethrum pulchrum Ledeb.) ургамлын эфирийн тосны химийн найрлагын судалгаа
 Хураангуй: Дэгжин шиваантиг (Pyrethrum pulchrum Ledeb.) нь Төв Ази болон Өмнөд Сибирийн уулархаг бүс нутгийн хад асгатай өндөр уулын бүслүүрт тархан ургадаг цэцэгт ургамал юм. Бид Монгол оронд ургадаг Дэгжин шиваантиг ургамлын газрын дээд хэсгийн эфирийн тосны химийн найрлагыг тодорхойллоо. Эфирийн тосыг усны уураар нэрж гарган авахад гарц 0.1% байв. Хийн хроматограф-масс спектрометрийн аргаар эфирийн тосны найрлаганд нийт 57 нэгдэл тодорхойлогдсон ба камфор (33.9%), линалоол (21.1%), α-пенин (9.0%), (Z)-γ-куркумил-2-метилбутират (4.82%), пентилкуркумен (3.21%), камфен (2.85%), трикосан (2.78%), неролидол (2.63%), α-селин (1.8%) ба β-пенин (1.4%) зэрэг нэгдлүүд зонхилон агуулагдаж байв. Энэхүү судалгааны ажил нь Дэгжин шиваантиг ургамлын эфирийн тосны судалгааг анх удаа хийж, танилцуулж буйгаар онцлог юм.
 Түлхүүр үгс: Нийлмэл цэцэгтэн , Дэгжин шиваантиг, Марал цэцэг, эфирийн тос

Susceptibility of opium poppy and pyrethrum to root infection by Spongospora subterranea

AbstractSpongospora subterranea, which causes powdery scab of potato, infects a diverse range of plant species. Crop rotation as a powdery scab management tool will be compromised if pathogen hosts exist between potato crops. Opium poppy (Papaver somniferum) and pyrethrum (Tanacetum cinerariifolium) are important crops within intensive vegetable production rotations in NW Tasmania. Measurements of S. subterranea soil inoculum within a commercial field showed pathogen amounts were substantially elevated following an opium poppy crop, which suggested host status. In glasshouse testing, opium poppy and pyrethrum were confirmed as hosts of S. subterranea, with opium poppy the more susceptible of the two. Both species were less susceptible than tomato, a known host. Observations of early growth suggested inoculation impacts on all three plant species, although at 16 (tomato and opium poppy) or 26 (pyrethrum) weeks postinoculation, only tomato had significantly reduced shoot and root development. The role of rotation crops in inoculum persistence and the possible role of S. subterranea as a minor pathogen of nonpotato crops are discussed.

Jasmone Hydroxylase, a Key Enzyme in the Synthesis of the Alcohol Moiety of Pyrethrin Insecticides

Pyrethrins are synthesized by the plant pyrethrum (Tanacetum cinerariifolium), a chrysanthemum relative. These compounds possess efficient insecticidal properties and are not toxic to humans and most vertebrates. Pyrethrum flowers, and to a smaller extent leaves, synthesize six main types of pyrethrins, which are all esters of a monoterpenoid acid moiety and an alcohol moiety derived from jasmonic acid. Here, we identified and characterized the enzyme responsible for the conversion of jasmone, a derivative of jasmonic acid, to jasmolone. Feeding pyrethrum flowers with jasmone resulted in a 4-fold increase in the concentration of free jasmolone as well as smaller but significant proportional increases in free pyrethrolone and all three type I pyrethrins. We used floral transcriptomic data to identify cytochrome P450 genes whose expression patterns were most highly correlated with that of a key gene in pyrethrin biosynthesis, T. cinerariifolium chrysanthemyl diphosphate synthase The candidate genes were screened for jasmone hydroxylase activity through transient expression in Nicotiana benthamiana leaves fed with jasmone. The expression of only one of these candidate genes produced jasmolone; therefore, this gene was named T. cinerariifolium jasmolone hydroxylase (TcJMH) and given the CYP designation CYP71AT148. The protein encoded by TcJMH localized to the endoplasmic reticulum, and microsomal preparations from N. benthamiana leaves expressing TcJMH were capable of catalyzing the hydroxylation of jasmone to jasmolone in vitro, with a Km value of 53.9 µm TcJMH was expressed almost exclusively in trichomes of floral ovaries and was induced in leaves by jasmonate.

Action of six pyrethrins purified from the botanical insecticide pyrethrum on cockroach sodium channels expressed in Xenopus oocytes

Pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmolin I and jasmolin II are six closely related insecticidal active esters, known as pyrethrins, found in the pyrethrum extract from the dry flowers of Tanacetum cinerariifolium. The chemical structures of the six compounds differ only in the terminal moieties at the acid and alcohol ends, but the compounds' in vivo toxicities are substantially different. Pyrethrins are lead compounds for pyrethroids, a large family of synthetic insecticides that alter nerve functions by prolonging the opening of voltage-gated sodium channels. However, data on the mechanism of action of natural pyrethrins are very limited. In this study, we examined the actions of all six pyrethrins on cockroach sodium channels expressed in Xenopus oocytes. Although the six compounds showed comparable potencies in inhibiting the inactivation of sodium channels, they had greatly variable potencies in inhibiting channel deactivation. Furthermore, unlike pyrethroids, the action of pyrethrins neither depend on nor were enhanced by repeated channel activation. We created a NavMs-based model of the cockroach sodium channel, in which pyrethrin II was docked at the pyrethroid receptor site 1 (PyR1), and proposed a rationale for the observed structure-activity relationship of the six pyrethrins. Our study sheds light on the molecular mechanism of pyrethrum action on sodium channels and reveled differences in the modes of action of the six bioactive constitutes of pyrethrum.

Production of trans-chrysanthemic acid, the monoterpene acid moiety of natural pyrethrin insecticides, in tomato fruit

The pyrethrum plant, Tanacetum cinerariifolium (Asteraceae) synthesizes a class of compounds called pyrethrins that have strong insecticidal properties but are safe to humans. Class I pyrethrins are esters of the monoterpenoid trans-chrysanthemic acid with one of three jasmonic-acid derived alcohols. We reconstructed the trans-chrysanthemic acid biosynthetic pathway in tomato fruits, which naturally produce high levels of the tetraterpene pigment lycopene, an isoprenoid which shares a common precursor, dimethylallyl diphosphate (DMAPP), with trans-chrysanthemic acid. trans-Chrysanthemic acid biosynthesis in tomato fruit was achieved by expressing the chrysanthemyl diphosphate synthase gene from T. cinerariifolium, encoding the enzyme that uses DMAPP to make trans-chrysanthemol, under the control of the fruit specific promoter PG, as well as an alcohol dehydrogenease (ADH) gene and aldehyde dehydrogenase (ALDH) gene from a wild tomato species, also under the control of the PG promoter. Tomato fruits expressing all three genes had a concentration of trans-chrysanthemic acid that was about 1.7-fold higher (by weight) than the levels of lycopene present in non-transgenic fruit, while the level of lycopene in the transgenic plants was reduced by 68%. Ninety seven percent of the diverted DMAPP was converted to trans-chrysanthemic acid, but 62% of this acid was further glycosylated. We conclude that the tomato fruit is an alternative platform for the biosynthesis of trans-chrysanthemic acid by metabolic engineering.

Influence of different treatments on the presence of olive fruit fly in Croatian Istria

Research was conducted in 2013 on the presence of one of the most important olive pests, olive fruit fly (Bactrocera oleae Gmel.), following different plant protection treatments in Kastelir near Porec (Croatia). In this research on an olive grove planted with the cultivar 'Leccino', the experiment was set up with five treatments: conventional plant protection, organic plant protection, pyrethrin, consociation of olive and planted pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.), and control. Olive fruit fly presence was monitored weekly using separate pheromone traps on each treatment, and comparison between the treatments was performed. The climatic conditions in Istria were also monitored during 2013. The average number of captured adult olive fruit flies varied between treatments, with the largest average number detected on the control (12.7), while the greatest presence of olive fly life stages was detected on organic treatments (3.8). The smallest average number of captured adult olive flies was detected on pyrethrin treatment (5.7), while the smallest presence of olive fly life stages was detected on conventional treatments (0.9); however, the differences in both these cases were not statistically significant. In addition, olive flies were monitored by yellow sticky trap. The highest yield was determined on conventional treatment (9.3 kg tree‑1), while the lowest yield was on consociation and organic treatment (8.8 kg tree‑1); however, the difference between the two was not statistically significant.

Modification of chrysanthemum odour and taste with chrysanthemol synthase induces strong dual resistance against cotton aphids.

SummaryAphids are pests of chrysanthemum that employ plant volatiles to select host plants and ingest cell contents to probe host quality before engaging in prolonged feeding and reproduction. Changes in volatile and nonvolatile metabolite profiles can disrupt aphid–plant interactions and provide new methods of pest control. Chrysanthemol synthase (CHS) from Tanacetum cinerariifolium represents the first committed step in the biosynthesis of pyrethrin ester insecticides, but no biological role for the chrysanthemol product alone has yet been documented. In this study, the TcCHS gene was over‐expressed in Chrysanthemum morifolium and resulted in both the emission of volatile chrysanthemol (ca. 47 pmol/h/gFW) and accumulation of a chrysanthemol glycoside derivative, identified by NMR as chrysanthemyl‐6‐O‐malonyl‐β‐D‐glucopyranoside (ca. 1.1 mM), with no detrimental phenotypic effects. Dual‐choice assays separately assaying these compounds in pure form and as part of the headspace and extract demonstrated independent bioactivity of both components against the cotton aphid (Aphis gossypii). Performance assays showed that the TcCHS plants significantly reduced aphid reproduction, consistent with disturbance of aphid probing activities on these plants as revealed by electropenetrogram (EPG) studies. In open‐field trials, aphid population development was very strongly impaired demonstrating the robustness and high impact of the trait. The results suggest that expression of the TcCHS gene induces a dual defence system, with both repellence by chrysanthemol odour and deterrence by its nonvolatile glycoside, introducing a promising new option for engineering aphid control into plants.