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BACKGROUND: Despite their known negative effects on ecosystems and human health, synthetic pesticides are still largely used to control crop insect pests. Currently, the biopesticide market for insect biocontrol mainly relies on the entomopathogenic bacterium Bacillus thuringiensis (Bt). New biocontrol tools for crop protection might derive from fungi, in particular from Trichoderma spp., which are known producers of chitinases and other bioactive compounds able to negatively affect insect survival. RESULTS: In this study, we first developed an environmentally sustainable production process for obtaining chitinases from Trichoderma asperellum ICC012. Then, we investigated the biological effects of this chitinase preparation – alone or in combination with a Bt‐based product – when orally administered to two lepidopteran species. Our results demonstrate that T. asperellum efficiently produces a multi‐enzymatic cocktail able to alter the chitin microfibril network of the insect peritrophic matrix, resulting in delayed development and larval death. The co‐administration of T. asperellum chitinases and sublethal concentrations of Bt toxins increased larval mortality. This synergistic effect was likely due to the higher amount of Bt toxins that passed the damaged peritrophic matrix and reached the target receptors on the midgut cells of chitinase‐treated insects. CONCLUSION: Our findings may contribute to the development of an integrated pest management technology based on fungal chitinases that increase the efficacy of Bt‐based products, mitigating the risk of Bt‐resistance development. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In light of the introduction of truffle cultivation into northern Israel, previously unrecorded damage to the edible ectomycorrhizal truffle Tuber aestivum in Northern Israel is described and attributed to the scarab beetle Ochodaeus berytensis (Coleoptera: Ochodaeidae). The unique presence of adults within the truffles indicates that the life cycle of O. berytensis occurs elsewhere, very likely at the expense of another, yet unknown, hypogeal fungus. The damage to the ripe stage of fruiting bodies of the truffle are substantial and consist of borings, tunnels and galleries comparable with those perpetrated by the truffle beetle pest Leiodes cinnamomea (Panzer, 1793) (Leiodidae). Although Ochodaeidae have long been assumed to be mycophagous, it is the first recorded association of these beetles with hypogeal fungi. A distribution map of O. berytensis within the country is provided. [ABSTRACT FROM AUTHOR]

Laurus nobilis L. is an aromatic medicinal plant widely cultivated in many world regions. L. nobilis has been increasingly acknowledged over the years as it provides an essential contribution to the food and pharmaceutical industries and cultural integrity. The commercial value of this species derives from its essential oil, whose application might be extended to various industries. The chemical composition of the essential oil depends on environmental conditions, location, and season during which the plants are collected, drying methods, extraction, and analytical conditions. The characterization and chemotyping of L. nobilis essential oil are extremely important because the changes in composition can affect biological activities. Several aspects of the plant's secondary metabolism, particularly volatile production in L. nobilis, are still unknown. However, understanding the molecular basis of flavor and aroma production is not an easy task to accomplish. Nevertheless, the time-limited efforts for conservation and the unavailability of knowledge about genetic diversity are probably the major reasons for the lack of breeding programs in L. nobilis. The present review gathers the scientific evidence on the research carried out on Laurus nobilis L., considering its cultivation, volatile composition, biochemical and molecular aspects, and antioxidant and antimicrobial activities. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pear psylla is amajor obstacle to efficient integrated pestmanagement in pear orchards in Israel and around the world.We used two accessions with natural resistance to pear psylla Cacopsylla bidens (Šulc) – Py.760-261 (760) and Py.701-202 (701), both apparently of Pyrus communis L. origin – as interstock grafts to confer psylla resistance to the commercially important 'Spadona Estiva' (Pyrus communis) scion (Spadona) cultivar. The interaction of the interstocks with quince (Cydonia oblong Mill.) and Pyrus betulifolia Bunge rootstocks was also tested. RESULTS: Usage of Py.760-261 (760) and Py.701-202 (701) as interstocks for the psylla-sensitive Spadona resulted in a five-fold decrease in the C. bidens population, apparently as a consequence of antibiosis affecting nymph survival. Additionally, psylla survival was negatively correlated with the interstock length and amount of foliage. The yield and fruit quality of Spadona grafted on the '701' interstock equaled or even exceeded those of the control in fruit quantity, fruit size and soluble solids content, especially on P. betulifolia rootstock. CONCLUSION: Susceptibility to pear psylla decreased significantly following grafting of commercial Spadona on resistant interstock. This is the first demonstration of increased resistance to pear psylla conferred by the use of resistant interstock in pear trees and among the few examples demonstrating transfer of resistance to insects from the interstock in fruit trees. [ABSTRACT FROM AUTHOR]

The tomato leafminer, Tuta absoluta (Meyrick), had established in Israel by 2010, attacking both open-field tomatoes and greenhouse crops. We searched for its natural enemies in open-field tomatoes, and tried to determine their potential for controlling this pest. We surveyed the local natural enemies in open tomato fields and measured their impact on pest populations in an unsprayed field. We assessed the suppressive ability of the dominant hemipteran predator, Nesidiocoris tenuis Reuter, against T. absoluta under controlled laboratory conditions and evaluated the impact of its augmentation on T. absoluta control in open-field tomatoes. We found five natural enemy species: the predator, N. tenuis, two braconids, and two eulophids. Predation accounted for 64.5±9.2% (mean±SE) of T. absoluta larval mortality, whereas parasitism accounted for 20.9±7.5%. Together, they eliminated the pest population at tomato harvest time. Under controlled conditions, predation by N. tenuis rose from 58 to 72% with increased density of T. absoluta, suggesting positive density dependence. The reduction of T. absoluta (83%) by N. tenuis was higher than that of Bemisia tabaci (32%), suggesting a preference of N. tenuis for T. absoluta. Augmentation of N. tenuis was as effective as conventional treatment insecticide treatment, and plant damage was low and did not seem to affect yield. Results indicate that reduced pesticide use enables indigenous natural enemies, particularly N. tenuis, to successfully control T. absoluta and prevent crop damage in open-field tomatoes. [ABSTRACT FROM AUTHOR]

BACKGROUND The pear psylla, Cacopsylla bidens (Šulc), is one of the most damaging pests of commercial pear orchards in Israel. Psylla control is a major obstacle to efficient integrated pest management, necessitating research on cultivars with natural resistance to pear psylla. Recently, two pear accessions (Py.760-261 and Py.701-202) from the local Newe Ya'ar fruit tree live collection were identified as having apparent resistance to pear psylla. Our goal was to evaluate the resistance of these two accessions relative to the commercial cultivar Spadona Estiva, and to identify whether the resistance mechanisms in the former interfere with insect colonisation of the plant (antixenosis) or inhibit insect growth, development, reproduction and survival (antibiosis). RESULTS Settlement and development of C. bidens was evaluated under natural conditions (pear orchard), semi-natural conditions (potted plants), and on detached branches and leaves (laboratory). Our results indicate that the selection Py.760-261 is 10 times more resistant than Spadona while Py.701-202 is five times more resistant. CONCLUSIONS The resistance mechanism in both accessions appears to be antibiosis affecting nymph survival. These resistant accessions may be used as rootstock or as a source of resistant genes in breeding programmes. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is an invasive Neotropical pest. After its first detection in Europe, it rapidly invaded more than 30 Western Palaearctic countries becoming a serious agricultural threat to tomato production in both protected and open-field crops. Among the pest control tactics against exotic pests, biological control using indigenous natural enemies is one of the most promising. Here, available data on the Afro-Eurasian natural enemies of T. absoluta are compiled. Then, their potential for inclusion in sustainable pest control packages is discussed providing relevant examples. Collections were conducted in 12 countries, both in open-field and protected susceptible crops, as well as in wild flora and/or using infested sentinel plants. More than 70 arthropod species, 20 % predators and 80 % parasitoids, were recorded attacking the new pest so far. Among the recovered indigenous natural enemies, only few parasitoid species, namely, some eulophid and braconid wasps, and especially mirid predators, have promising potential to be included in effective and environmentally friendly management strategies for the pest in the newly invaded areas. Finally, a brief outlook of the future research and applications of indigenous T. absoluta biological control agents are provided. [ABSTRACT FROM AUTHOR]

The pear psylla, Cacopsylla bidens (Sulc), is one of the most damaging pests of commercial pear orchards in Israel. However, growers today have only two pesticides left to control the pear psylla, therefore alternative control methods are needed. Our goal was to find ways to control the psylla population through rational use of cultural control methods: manipulating the levels of nitrogen fertilization, and using growth regulators. Our objectives were to determine the impact of nitrogen fertilization level on pear psylla populations, the impact of application of plant growth regulators (clormequat chloride and prohexadion-calcium) on psylla populations, and whether there is an interaction between the two factors in a semi-field-scale and in field-scale experiments. Higher oviposition and nymph development rates were found in trees that had higher leaf-nitrogen contents. Lower oviposition, nymph survival, and nymph development rates were found in trees that were treated with growth regulators. The suppressive impact of growth regulators was expressed even in trees with high nitrogen levels. We concluded that psylla population levels in pear trees can be reduced by using lower levels of nitrogen fertilization and that growth regulators impair psylla growth and development, and may possibly be used to reduce psylla populations. [ABSTRACT FROM AUTHOR]

• Wild carrot accession was identified to constitutively attracts the carrot psylla. • Wild carrot accession possesses potent insecticidal activity on carrot psylla. • Carrot psylla prefers wild carrot accession for oviposition in the choice experiment. • In the non-choice, psylla prefers the Nairobi carrots for egg-laying. • Myristicin and sabinene exogenous applications possess insecticidal activity. Carrot psylla is one of the devastating pests of carrot throughout northern Europe and the Mediterranean basin. Here we characterized the behavioral response of psylla females towards different carrot germplasm and identified the chemical cues involved in the host selection of psylla females by oviposition choice experiments and metabolic profiling of leaf volatiles. In choice assays, carrot psylla displayed differential responses to tested 14 germplasm. Among germplasm, wild accessions 21793 and 20465 were highly preferred by carrot psylla, while wild accessions 20465 and the orange cultivar Nairobi were less. In non-choice experiments conducted only with this four-germplasm revealed that the carrot psylla females gave higher preference to the Nairobi and wild accession 20465, indicating the vicinity to other host plants in the same area might affect female preference. Moreover, the nymph development and survival experiments showed the lowest nymphs survival rate on the wild accessions 21793 and 20497. Furthermore, the volatile emissions among different carrot cultivars infested with psylla showed qualitative and quantitative differences versus intact plants. Among these volatiles, apiol, β -asarone, myristicin, and sabinene showed a relationship with psyllas growth and survival. We also showed that myristicin and sabinene exogenous applications caused a dramatic reduction in the number of eggs laid by psylla and subsequent nymph survival. This is an initial study of the volatiles that mediate attraction and oviposition preference of carrot psylla in response to its host plant. The results from this study provide baseline information for the development of new control strategies against carrot psylla. [ABSTRACT FROM AUTHOR]

Nesidiocoris tenuis (Heteroptera: Miridae) is a predator of some major pests of Solanaceae crops, yet it is scarcely used in biological control because it also feeds on plants and may damage crops. The study of N. tenuis biology may promote the ability to use it as a biological control agent. Because N. tenuis, like some other insect taxa, oviposits into plant tissues, its eggs are hard to detect. This limits our ability to study N. tenuis - plant interactions. We therefore looked for a staining method for plant-embedded eggs, which will allow their detection within tomato plants, a common host of N. tenuis. We first used lactophenol solution with acid fuchsin to stain eggs inside tomato foliage. Because of the high toxicity of lactophenol, we later substituted lactophenol with a lactoglycerol solution, which was found to be similarly efficient. Five minutes immersion in the staining solution at 80°C followed by a two-minute soak in hot water made the eggs stain deep red, while the foliage became transparent and was stained weak red. Eggs within leaves were easily visible under 10-30x magnification with sub-stage lighting; top-lighting was needed for the detection of eggs embedded in less-transparent tissues such as stems. This rapid staining method improves the ability to study some important biological aspects of N. tenuis, such as its fecundity. Also, the elimination of phenol made the method cheaper and safer to use. Finally, this method may be adapted for other arthropod-plant systems. [ABSTRACT FROM AUTHOR]

• Pollination showed a negative effect on black fig fly oviposition as well as volatiles emission in Ficus carica. •Eight terpene synthases were identified from fig fruits. • Expression analysis suggests that the enzymes may play a role in terpene volatiles biosynthesis. The black fig fly (Silba adipata) is one of the major pests of figs worldwide. This study investigated the effect of pollination on black fig fly infestation and volatile emission during fruit development of facultative parthenocarpic Ficus carica. The results from in-field oviposition preference of black fig fly, olfactory analysis, and fruit volatile profiles indicate that the black fig fly gave a strong preference to unpollinated figs that showed higher emissions of volatile organic compounds. Terpenes are known to be important compounds determining many insect-plant interactions, so we report a transcriptome-based identification and functional characterization of a terpene synthase (TPS) gene family in F. carica. The protein expression in Escherichia coli of eight terpene synthases (TPSs) revealed that three were monoterpene synthases belonging to the TPS-b clade, with FcTPS6 catalyzing the formation of 1,8-cineole while the other two converted GPP into linalool. Four sesquiterpene synthases from the TPS-a clade catalyze the formation of germacrene D (FcTPS1), E - β -caryophyllene (FcTPS2), cadinene (FcTPS3) and δ -elemene (FcTPS5) while one sesquiterpene synthase FcTPS4 from the TPS-b clade showed nerolidol synthase activity. Most of the enzymatic products closely matched the volatile terpenes emitted from fig fruits and all the genes were expressed during fruit development. This study provides new insights into fig-insect interactions and understanding the molecular mechanisms of terpene biosynthesis and could provide the foundations for sustainable pest management strategies. [ABSTRACT FROM AUTHOR]

• Apocarotenoids emission changed substantially during fig fruit development. • Carotenoid cleavage dioxygenase 1 genes were identified and characterized from fig fruit. • In vitro, recombinant FcCCD1A cleaved cyclic carotenoids producing α and ß ionone. • FcCCD1B showed 5-6 (5'-6') double bond specificity for acyclic moiety of carotenoids. • qPCR analysis revealed FcCCD1 expression during all stages of fruit development. In plants the oxidative cleavage of carotenoid substrates produces volatile apocarotenoids, including β -ionone, 6-methyl-5-hepten-2-ol, and α -ionone; these compounds are important in herbivore-plant communication. Combined chemical, biochemical, and molecular studies were conducted to evaluate the differential accumulation of carotenoids and volatile apocarotenoids during the development of pollinated and parthenocarpic fig fruits. Pollinated fig fruits showed less emission of apocarotenoid volatiles than the parthenocarpic figs, while in the case of carotenoid pigments, pollinated figs manifested higher accumulation. The apocarotenoids, 6-methyl-5-hepten-2-ol and β -cyclogeraniol, showed a marked increase after the two weeks of hand-pollination in pollinated and parthenocarpic figs; but afterwards these volatile levels decreased during further fruit development. In addition, we report a transcriptome-based identification and functional characterization of the carotenoid cleavage dioxygenase (FcCCD) genes. These genes were overexpressed in Escherichia coli strains previously engineered to produce different carotenoids. The recombinant FcCCD1A enzyme showed specificity for the 9,10 (9′,10′) double bond position of cyclic carotenoids to generate α -ionone and β -ionone, while FcCCD1B cleaved lycopene and an acyclic moiety of δ -carotene, producing 6-methyl-5-hepten-2-one. The qRT-PCR analysis of FcCCD genes revealed differential gene expression during fig fruit development. Our results suggest a role for the FcCCD1 genes in apocarotenoid biosynthesis in fig fruits. [ABSTRACT FROM AUTHOR]

Abstract Styrene analogs are known to be naturally synthesized in the leaves of pears and in other plant species, including several trees in the Styracaceae family. Styrene analogs are potential contributors to the aroma of wine, perfumes, pharmaceuticals, and other fermented foods and beverages. In addition, styrene analogs perform important ecological functions such as insecticidal and antifeedant activities against insects. We showed here that exogenous applications of styrene and p -hydroxystyrene caused a dramatic reduction the number of eggs laid by psylla and of subsequent nymph survival. Despite their importance specific reactions that lead to the biosynthesis of the styrene analogs in pear are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for pear genes with significant sequence similarity to bacterial phenolic acid decarboxylase. Herein described are the isolation and characterization of a pear phenolic acid decarboxylase, designated PyPAD1, which catalyzed the decarboxylation of p -coumaric acid and ferulic acid to p -hydroxystyrene and 3-methoxy-4-hydroxystyrene respectively. Its apparent Km values for p -coumaric acid and ferulic acid were 34.42 and 84.64 μM, respectively. The PyPAD1 preferred p -coumaric acid to ferulic acid as a substrate by a factor of 2.4 when comparing catalytic efficiencies in vitro. Expression analysis of PyPAD1 showed that the gene was transcribed in all five pear genotypes examined. However, transcript abundance was increased in correlation with the presence of p -hydroxystyrene in resistant cultivars Py-701 and Py-760 and in the sensitive cultivar Spadona when grafted on these resistant cultivars. Thus, PyPAD1 appears to be responsible for the decarboxylation of the p -coumaric acid, and for the production of metabolites that are active against pear psylla. Graphical abstract Image 1 Highlights • Phenolic acid decarboxylase was identified and characterized from pear leaves. • PyPAD1 catalyses the decarboxylation of p -coumaric acid and ferulic acid to p -hydroxystyrene and 3-methoxy-4-hydroxystyrene. • PyPAD1 prefers p -coumaric acid over ferulic acid as a substrate. • Expression analysis suggests that the enzyme may play a crucial role in biosynthesis of styrene analogs. [ABSTRACT FROM AUTHOR]

No-tillage (NT) is a common soil-conservation management practice with known agricultural advantages and drawbacks. However, its short- and long-term effects on the soil microbiome have not been well established. Here, we compared conventional (CT), minimal (MT) and NT practices in two agricultural fields in the north of Israel over a period of 3 years. Edaphic properties, plant-associated pests, weed species abundance and soil microbial community structure were assessed to examine the effects of tillage. Tillage significantly altered physical and chemical soil properties, and a significant increase in hydrolytic and redox microbial activities was observed in NT soils from both sites. Consistent with this, the microbial community structure of NT samples diverged significantly over time from those of CT samples. Repetitive tillage and even a single tillage event caused significant changes in the relative abundance of microorganisms at taxonomic levels ranging from phylum to OTU. However, no significant difference between treatments was found in microbial community alpha-diversity or crop yield. Conversely, higher levels of weed diversity and some pests number were found in NT samples. Overall, we demonstrate that tillage plays a major role in shaping microbial community structure, and in influencing additional environmental, ecological and agricultural soil parameters. Unlabelled Image • Continuous no-tillage affected soil microbial community structure and activity. • Even a single tillage event affected the soil microbiome. • Continuous yearly tillage affected soil chemical, physical and agricultural parameters. [ABSTRACT FROM AUTHOR]

• Seven terpene synthases were identified from almond (Prunus dulcis). • Four almond terpene synthases falls into the monoterpene synthases clade b. • Two almond terpene synthases (PdTPS2, and PdTPS4) belong to the sesquiterpene synthases clade a. • The almond PdTPS7 belongs to the TPS clade g. • Expression analysis suggests that the enzymes may play a role in terpene volatiles biosynthesis. Almond (Prunus dulcis) is an agricultural and economically important fruit tree from the Rosaceae family used in the food industry. The monoterpenes and sesquiterpenes perform important ecological functions such as insecticidal and antifeedant activities against various insects. The young fruits of the different almond varieties were found to produce considerable amounts of terpene volatiles, including linalool and geraniol. To identify terpene synthases (TPSs) involved in the production of these volatile terpenes, existing genome databases of the Rosaceae were screened for almond genes with significant sequence similarity to other plants TPSs. Bioinformatics analysis led to the identification of seven putative TPSs genes with complete open reading frames. We characterized the enzymes encoded by these seven complementary DNAs: the monoterpene synthases PdTPS1, PdTPS3, PdTPS5, and PdTPS6 belong to the TPS-b clade, which catalyzes the formation of β -phellandrene, geraniol, linalool, and farnesene, respectively. The sesquiterpene synthases PdTPS2 and PdTPS4, which belong to the TPS-a clade mainly catalyze the formation of bergamotene, while another sesquiterpene synthase, PdTPS7, from the TPS-g clade showed nerolidol synthase activity. The qRT-PCR analysis revealed that the various tissues of almond varieties showed differential transcription for all these PdTPSs genes. [ABSTRACT FROM AUTHOR]

Background: Pear psylla is a major obstacle to efficient integrated pest management in pear orchards in Israel and around the world. We used two accessions with natural resistance to pear psylla Cacopsylla bidens (Šulc) - Py.760-261 (760) and Py.701-202 (701), both apparently of Pyrus communis L. origin - as interstock grafts to confer psylla resistance to the commercially important 'Spadona Estiva' (Pyrus communis) scion (Spadona) cultivar. The interaction of the interstocks with quince (Cydonia oblong Mill.) and Pyrus betulifolia Bunge rootstocks was also tested., Results: Usage of Py.760-261 (760) and Py.701-202 (701) as interstocks for the psylla-sensitive Spadona resulted in a five-fold decrease in the C. bidens population, apparently as a consequence of antibiosis affecting nymph survival. Additionally, psylla survival was negatively correlated with the interstock length and amount of foliage. The yield and fruit quality of Spadona grafted on the '701' interstock equaled or even exceeded those of the control in fruit quantity, fruit size and soluble solids content, especially on P. betulifolia rootstock., Conclusion: Susceptibility to pear psylla decreased significantly following grafting of commercial Spadona on resistant interstock. This is the first demonstration of increased resistance to pear psylla conferred by the use of resistant interstock in pear trees and among the few examples demonstrating transfer of resistance to insects from the interstock in fruit trees. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)