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The Influence of Lead and Acyrthosiphon pisum (Harris) on Generation of Pisum sativum Defense Signaling Molecules and Expression of Genes Involved in Their Biosynthesis
The main aim of this study was to understand the regulation of the biosynthesis of phytohormones as signaling molecules in the defense mechanisms of pea seedlings during the application of abiotic and biotic stress factors. It was important to identify this regulation at the molecular level in Pisum sativum L. seedlings under the influence of various concentrations of lead—i.e., a low concentration increasing plant metabolism, causing a hormetic effect, and a high dose causing a sublethal effect—and during feeding of a phytophagous insect with a piercing-sucking mouthpart—i.e., pea aphid (Acyrthosiphon pisum (Harris)). The aim of the study was to determine the expression level of genes encoding enzymes of the biosynthesis of signaling molecules such as phytohormones—i.e., jasmonates (JA/MeJA), ethylene (ET) and abscisic acid (ABA). Real-time qPCR was applied to analyze the expression of genes encoding enzymes involved in the regulation of the biosynthesis of JA/MeJA (lipoxygenase 1 (LOX1), lipoxygenase 2 (LOX2), 12-oxophytodienoate reductase 1 (OPR1) and jasmonic acid-amido synthetase (JAR1)), ET (1-aminocyclopropane-1-carboxylate synthase 3 (ACS3)) and ABA (9-cis-epoxycarotenoid dioxygenase (NCED) and aldehyde oxidase 1 (AO1)). In response to the abovementioned stress factors—i.e., abiotic and biotic stressors acting independently or simultaneously—the expression of the LOX1, LOX2, OPR1, JAR1, ACS3, NCED and AO1 genes at both sublethal and hormetic doses increased. Particularly high levels of the relative expression of the tested genes in pea seedlings growing at sublethal doses of lead and colonized by A. pisum compared to the control were noticeable. A hormetic dose of lead induced high expression levels of the JAR1, OPR1 and ACS3 genes, especially in leaves. Moreover, an increase in the concentration of phytohormones such as jasmonates (JA and MeJA) and aminococyclopropane-1-carboxylic acid (ACC)-ethylene (ET) precursor was observed. The results of this study indicate that the response of pea seedlings to lead and A. pisum aphid infestation differed greatly at both the gene expression and metabolic levels. The intensity of these defense responses depended on the organ, the metal dose and direct contact of the stress factor with the organ.
The Role of Flower Strips in Increasing Beneficial Insect Biodiversity and Pest Control in Vineyards
In ecosystems that have been disturbed by agricultural management, ecosystem services such as adequate pest control are also disturbed. Exploiting interactions between beneficial insects and plants can contribute to improving ecosystem service delivery and biological control. One of the effective methods of naturally increasing the biodiversity of beneficial insects on crop plantations is the use of plant strips. The aim of our work was to demonstrate the role of flower strips in the sustainable management of vineyards. In particular, the relationship between the composition and flowering time of plants in flower strips and beneficial insects such as predators, parasitoids, and wild pollinators from Central Europe and the Western USA was shown. Most plants used for flower strips belong to the Asteraceae family. The most attractive to beneficial insects were Eriogonum niveum, Ericameria nauseosa, and Purshia tridentata in the USA, while in the vineyard in Poland they were garden plant species but also native species, especially Erigeron annuus, Taraxacum ssp., and Polygonum persicaria. The planned replacement of flowering times of plant species was observed from March to October, which ensured continuity in the availability of food for beneficial insects. Appropriately selected plants can attract selected species of predators and parasitoids, which can regulate the number of a specific pest species. Diversifying agricultural ecosystems is a promising pest control strategy that reduces pesticide use and thus supports sustainable agriculture.
Potwierdzenie występowania Nesidiocoris tenuis (Reuter, 1895) (Hemiptera: Miridae) w Polsce
For over 5 years, in the countries of north-western Europe, there has been a growing threat of a new pest, which does not yet have a Polish name, and whose presence has been confirmed from production facilities in Poland in the last 3 years. Nesidiocoris tenuis is a true bug that pierces the plant and sucks the sap from the phloem. In places of feeding, tissue necrosis occurs, leading to deformations, brown rings and, consequently, inhibition of the growth of punctured plant parts. Paradoxically, in the Mediterranean countries, this insect has been treated as a useful predator for years and, as part of biological protection, used to fight the tomato moth Tuta absoluta.
New alien and invasive bamboo aphid species of the genus Takecallis (Hemiptera: Aphididae) recorded in Poland – morphological and molecular identity
The occurrence of three bamboo aphid species of the genus Takecallis was detected. T. arundicolens (Clarke) and T. arundinariae (Essig) were recorded for the first time in Poland, and new localities for T. nigroantennatus Wieczorek were found. Key diagnostic morphological characteristics to help distinguish these species and DNA barcoding to analyze individuals at the molecular level were provided.
Population Development of Alien Gall-Forming Aphid Tetraneura nigriabdominalis on Ulmus minor and Ulmus glabra
Tetraneura (Tetraneurella) nigriabdominalis (Sasaki, 1899) is a holocyclic and heteroecious species widely distributed throughout the world. Its primary hosts are various elm species, on which it forms galls. The results of this study complement those of previous research on the development of T. nigriabdominalis on primary hosts. Our research was conducted on two elm species, Ulmus minor and Ulmus glabra, at three locations and for three successive seasons between 2017 and 2019. Fundatrices hatched between 27 April and 12 May. The first galls were observed 6–8 days after the hatching date of the fundatrices. On average, there were 1–7.5 galls on one leaf. The highest abundances of T. nigriabdominalis galls were found in the medial and basal parts of the leaf blades. The fundatrices matured within 12–21 days after hatching and produced nymphs within 2–3 weeks. The fecundity of the fundatrices was influenced by the temperature in April, the size of the laminae, and the size of the galls. The females developing on U. glabra were more fecund (2–58 nymphs), whereas those developing on U. minor produced 1–29 nymphs. The winged migrants of the second generation appeared between late May and late June, when the first cracks on the galls were also observed. The entire development of two aphid generations on the primary host was temperature-dependent and lasted from four to almost six weeks. Our results show that U. glabra and U. minor are suitable hosts for T. nigriabdominalis. The development of aphids proceeded similarly on both tree species. Temperature, especially in April, significantly influenced the duration of individual developmental phases and the fecundity of fundatrices.
Tracing the Invasion of Takecallis nigroantennatus (Hemiptera, Aphididae) on Cold-Hardy Bamboo Fargesia Using Mitochondrial COI Data
The introduction of alien insect species is increasingly facilitated by global plant trade, particularly through the movement of ornamental plants. Takecallis nigroantennatus, a host-specific aphid associated with cold-hardy Fargesia bamboo, has recently expanded its range in Europe. To examine its invasion dynamics, we conducted a population-level survey across 13 locations in six countries, sampling individuals from botanic and private gardens, specialized bamboo nurseries, garden centers, and urban horticultural environments in the UK, Belgium, The Netherlands, Germany, Poland, and Norway. A total of 117 specimens were analyzed using mitochondrial COI sequences, revealing a single dominant haplotype without geographic structure based on Bayesian and Maximum Likelihood phylogenetic analyses. This striking genetic uniformity indicates a narrow introduction bottleneck, suggesting a single or highly restricted introduction event followed by clonal spread. Despite the species’ ability for sexual reproduction, the data support a founder effect and rapid recent expansion closely linked to the introduction history of Fargesia in Europe. The results are also consistent with a possible time lag between the arrival of ornamental bamboo and the subsequent establishment of its associated herbivore, a scenario that warrants further investigation. Importantly, our study provides a practical framework for applied monitoring and early detection in bamboo nurseries, botanical gardens, and other high-risk introduction sites, illustrating how molecular tools can inform biosecurity and the management of emerging invasive species.
Adapting to change: exploring the distribution dynamics of the alienand potentially invasive aphid species Cinara curvipes (Hemiptera:Aphididae) in the context of global warming
Takecallis nigroantennatus Wieczorek (Hemiptera: Aphididae) – implications of the ability to holocycle and overwintering of eggs on the spread of a potentially invasive bamboo aphid species
The bamboo-feeding aphid genus Takecallis (Hemiptera: Aphididae) contains eight taxa of Oriental origin. Four of them are introduced to Europe, where they are treated as a pest on Bambusoideae, showing invasive behavior with regard to range expansion, host plant spectrum and the ability to engage in an anholocyclic (without sexual phase) mode of reproduction. In contrast, the current field study confirms that the newly described species, the hardy bamboo aphid Takecallis nigroantennatus, reproduces holocyclically in temperate climatic conditions. The previously unknown morphs, i.e. the oviparous females and winged males, are described and illustrated in light and scanning electron microscopy. Chlorophyll fluorescence measurements were employed to evaluate the effects of insect feeding on the photosynthetic performance and general health of the host plant. The implications of the ability to holocycle and the overwintering of eggs on the spread of a potentially invasive aphid species are discussed.
Composition of fatty acids in hemp leaves (Cannabis sativa L.) under the impact of aphids and a herbicide
Cannabis aphid Phorodon (Diphorodon) cannabis Passerini 1860 is an economically important pest of oil hemp (Cannabis sativa L.) and is controlled by insecticides. Oil hemp crops are treated with herbicides, which are non-target pesticides for aphids but may also affect aphid populations. Such ecological implications of plant protection products are rarely investigated. The aim of the present research was to better understand plant ‒ aphid ‒ herbicide interactions, specifically, changes of fatty acids (FAs) in leaves, caused by cannabis aphids and a common herbicide used in hemp fields. Of 21 FAs detected in hemp leaves, aphid feeding significantly increased the amounts of myristic and oleic acids and decreased the content of α-linolenic acid. This effect was found when aphids fed on hemp plants and especially when plants were treated with an herbicide containing quizalofop-P-tefuryl. This compound on its own did not affect the FA composition. In spite of the extremely high increase of myristic acid (7- to 9-fold, depending on the experiment variant), which could cause the repellent effect in hemp plants, the decreased amount of α-linolenic acid, the precursor of jasmonic acid may have helped aphids to manipulate the jasmonate signaling pathway involved in plant defense to herbivory enabling their continued feeding on hemp. This study revealed the importance of FAs in plant defense as well as the side effects of non-target plant protection products. Future pest management should take into account the complex interactions between crop plants, their pests and non-target effects of chemicals used in real field situations.