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Citrus canker is an important disease caused by Xanthomonas axonopodis pv. citri that affects citrus species. We isolated a bacterium denominated QC-Y with a strong inhibitory effect on citrus canker from navel orange leaves. The isolate was identified as Bacillus amyloliquefaciens based on the morphological, physiological, and biochemical characteristics and the 16S rDNA sequence analysis. The inhibitory activity of the pathogen was significantly affected by environmental factors such as the medium, inoculation amount, media volume, and pH. The biocontrol strain QC-Y effectively colonised on navel orange leaves, and the colonisation gradually decreased with time. Twelve days after inoculation, the isolate maintained a certain population level in the leaves. Mancozeb demonstrated a strong inhibitory effect on the growth of QC-Y; Chlorpyrifos at high concentrations inhibited QC-Y. Thiophanate-methyl, Bordeaux mixture, Kasugamycin, Imidacloprid, amino acid, Difenoconazole, Etoxazole, Alphacypermethrin, Buprofezin, Spirodiclofen, Avermectin, and Pyraclostrobin had no effect on the growth of QC-Y. In the detached leaf assay, compared with the leaves inoculated with the pathogens only, the disease incidence of the leaves treated with QC-Y was reduced by 77.5% and the lesions were smaller. Our findings reveal that Bacillus amyloliquefaciens QC-Y can be used as a potential biocontrol agent against the citrus canker disease.

The cultivation of cruciferous crops is threatened by extensive yield losses caused by the soil-borne pathogen Plasmodiophora brassicae Woronin, 1877. The objective of the study was to assess the potential of the bacterial product BactoMix 5 for the control of clubroot on a naturally infested soil in growth chamber trials using a P. brassicae-specific qPCR methodology. The results did not show a significant decrease in the P. brassicae in the soil nor a reduction of the disease symptoms on the plants. The native soil microbiota may have exhibited an antagonistic activity against the bacterial species from BactoMix 5 and evoked the poor effect of the product. Therefore, potential biological control agents should be tested with native soil microbiota and the regional production should be advanced to increase the product efficacy in the environment

The night temperature is one of the critical environmental factors affecting the grape berry quality. The objective of this study was to clarify whether a high night temperature promotes downy mildew on grapevines. The high night temperature conditions suppressed the gene expression of the pathogenesis-related proteins in the grapevine cultured cells and grapevine seedlings compared with the control night temperature conditions. The Plasmopara viticola colony formation on the leaves of the seedlings exposed to the control night temperature conditions became slightly noticeable on day 5 after inoculation, whereas a large number of colonies were clearly observed on the leaves of the seedlings exposed to the high night temperature conditions. On day 10 after inoculation, the leaf defoliation and withering were marked in the P. viticola infected seedlings exposed to the high night temperature conditions. The high night temperature conditions promoted the P. viticola zoospore germination. These results suggest that the high night temperature promoted the grape downy mildew by attenuating the constitutive plant defence re­sponse as well as enhancing the P. viticola early infection. Viticulturists should be vigilant regarding pest management strategies against the P. viticola primary infection of grapevines when high night temperatures continue for a long time.

Sunflower downy mildew (Plasmopara halstedii) is one of the major diseases that can be controlled by using resistant cultivars and seed dressings; however, several isolates have developed tolerance to some fungicides and the resistance has also been overcome by new pathotypes. We aimed to examine the pathotype distribution in Hungary and to test the pathotypes' mefenoxam sensitivity. The isolates, which provided the basis of the research were collected from different regions of Hungary between 2014 and 2017 and, later, their pathotypes were identified. According to our results, pathotype 704 was one of the most widespread in Hungary, but pathotype 730, pathotype 724 and pathotype 700 were also detected. Seven out of ten isolates caused relatively high disease rates on the mefenoxam-treated and inoculated sunflower plants with P. halstedii. The pathogen has a high genetic variability which enhances the possibility to develop fungicide resistance. Furthermore, this variability can easily contribute to the breakdown of the resistant genes of the resistant hybrids. Both features can reduce the effectiveness of management; therefore, the continuous monitoring of this oomycete is very important.

Monilinia laxa, Monilinia fructicola and Monilinia fructigena are the three main causal agents of brown rot, which is one of the most important diseases of stone fruits in pre- and postharvest conditions. Nowadays, the need for the precise genotyping of these Monilinia species in terms of the genetic diversity of their populations or differences in their pathogenicity and host range is a prerequisite for any efficient disease management. In our study, the genetic structure of Monilinia populations in Serbia from three geographically distinct regions was investigated employing a high-resolution melting (HRM) analysis which is a sensitive and rapid molecular approach in fungal ge­notyping and diagnostics. Using species-specific primer pairs genotype-specific HRM melting curve profiles were generated allowing to efficiently decipher the genetic diversity of the Monilinia populations. The Monilinia genotypes could be easily distinguished according to their melting curves. The isolates from the northern region were assigned to distinct genotypes and grouped rather independently compared to the isolates of the other two regions among all three tested Monilinia spp. M. fructicola and M. fructigena showed a higher genetic diversity among their populations (44%) compared with the genetic diversity among the M. laxa populations (7%). In contrast, the genetic variance within the pathogen populations was higher in the case of M. laxa (93%). Our data revealed an absence of host specificity in the Monilinia spp. populations.

Thrips can cause considerable economic damage. In order to reduce the use of agrochemicals research has also focused on different natural enemies. We used bibliometric mapping and visualization to understand the structure of this field. Articles from Web of Science as well as software Vosviewer were used. Analysis of co-occurrence of terms shows the principal research areas: transmission of viruses, chemical or biological control and new species. A third of articles refer to biological control. Visualizations reveal three major groups of beneficials: entomopathogens, parasitoids, and predators. Recently, attention has shifted mainly to predatory mites as biocontrol agents. Our analysis aims to make such information visually more explanatory with better overview of research directions.

The impacts of intercropping of canola (Ca) with faba beans (Fb), field peas (Fp), garlic (G), or wheat (Wh) were evaluated on the cabbage aphid, Brevicoryne brassicae (Linnaeus, 1758), natural enemies and canola yields in row ratios of 3Ca : 3Fb, 3Ca : Fp, 3Ca : 3G, and 3Ca : 3Wh in 2018 and 2019. In both years, the lowest aphid population was recorded in 3Ca : 3G. In 2018, the aphid population was significantly (P < 0.05) lower in 3Ca : 3Fp than in the monoculture, while, in 2019, it was lower in the intercrops compared to the monoculture. Furthermore, none of the intercrops, except 3Ca : 3Fb, showed a significant increase in the predator diversity and parasitism rate. The dry seed weight loss was higher in the monoculture and 3Ca : 3Wh than in the other intercrops. Based upon the obtained results, decreasing the density of the cabbage aphid and increasing the canola yield by intercropping canola with the faba bean, the field pea or garlic is possible with this system. The inferences of these outcomes, which are associated with the integrated pest management (IPM) in canola cropping systems, are discussed.

Diplodia sapinea is a common forest pathogen on Pinus spp. in a large part of the world. In 2013, disease caused by this pathogen on Scots pine (Pinus sylvestris) trees in Sweden was reported for the first time. In this study, we report the first detection of D. sapinea on diseased seedlings of P. sylvestris from two Swedish forest nurseries. Infected seedlings were collected July-November 2019. Diplodia sapinea was identified by morphological characteristics of fungal structures on plant tissues and from culture grown on Hagem agar media, followed by sequencing of fungal ITS rDNA. The result emphasizes the susceptibility of P. sylvestris seedlings. More research is needed to better understand the risk for disease spreading within forest nurseries and into the forest through infected plant material.

In the last few decades, the spiraea aphid (Aphis spiraecola Patch) has become a widely distributed pest of apple and citrus orchards across Europe. In our study, A. spiraecola was observed for the first time in Kosovo, Slovakia, the Czech Republic, the United Kingdom and Denmark, in apple orchards in the growing seasons of 2016, 2018 and 2019. The presence of A. spiraecola was also recorded on other host plants such as the quince (Cydonia oblonga Miller) and Vanhoutte spiraea (Spiraea × vanhouttei) in Slovakia, and the quince, common pear (Pyrus communis Linnaeus) and firethorn (Pyracantha coccinea M.J. Roemer) in the United Kingdom. Based on the morphological characteristics and the sequencing of the DNA mitochondrial cytochrome c oxidase subunit 1 gene (COI fragment) barcode, our study confirms the presence of this pest in five additional regions in Europe.

Bacterial fruit blotch (BFB) caused by Acidovorax citrulli, represents one of the most destructing diseases of cucurbits, especially to watermelon- and melon producing-regions. This disease has been spread sporadically to many countries globally, due to the unintentionally dispersal of contaminated commercial seeds. The BFB causes massive yield losses up to 100% under conducive conditions. Once infected, all parts of the host plants are extremely susceptible to this bacterium, especially the seedlings and fruits parts. In recent years, various management approaches and detection tools have been employed to control A. citrulli. Genotypic characterization methods revealed two distinct groups of A. citrulli strains; (i) group I strains primarily isolated from non-watermelon cucurbits and consist of moderate to highly aggressive strains from wide range of cucurbit hosts, and (ii) group II strains isolated from watermelon which are highly aggressive on watermelon, but mildly aggressive on non-watermelon hosts. In this paper, an attempt has been made to review research findings where the impact of diverse methods and management approaches were applied in detection and controlling of A. citrulli infection. A better understanding of this devastating bacterium will serve as guidelines for agricultural practitioners in developing the most efficient and sustainable BFB control strategies.

Agricultural practices depend mainly on the use of chemical fertilisers, pesticides, and herbicides which have caused serious health hazards and have also contributed to the pollution of the environment at large. The application of plant-beneficial rhizobacteria in agrarian practices has become paramount in increasing soil fertility, promoting plant growth, ensuring food safety, and increasing crop production to ensure sustainable agriculture. Beneficial rhizobacteria are soil microorganisms that are eco-friendly and serve as a modern method of improving the plant yield, protecting the plant and soil fertility that pose no harm to humans and the environment. This eco-friendly approach requires the application of beneficial rhizobacteria with plant growth-promoting traits that can improve the nutrient uptake, enhance the resistance of plants to abiotic and biotic stress, protect plants against pathogenic microorganisms and promote plant growth and yield. This review article has highlighted the multitasking roles that beneficial rhizobacteria employ in promoting plant growth, food production, bioremediation, providing defence to plants, and maintaining soil fertility. The knowledge acquired from this review will help in understanding the bases and importance of plant-beneficial rhizobacteria in ensuring agricultural sustainability and as an alternative to the use of agrochemicals.

Clavibacter michiganensis subsp. michiganensis (Cmm) is one of the phytopathogenic bacteria causing bacterial wilt disease and severe yield losses in tomatoes and other solanaceous vegetables. Although there are some reports on Cmm infections in eggplants (Solanum melongena), there is no information available on the resistance sources and genetic control of the resistance to Cmm in this crop. We performed a search for resistance sources to Cmm in eggplants, in a set of 46 genotypes including landraces, inbred lines and cultivars and some cultivated and wild relatives, as well as an analysis of the genetic control of the resistance. A mixture of different Cmm strains from different genomic groups was used for the screening. Plants were inoculated through the injection of 10 µL of a Cmm suspension at a concentration of 10⁷ cfu/mL in a single point of the stem. The symptoms were recorded at nine weeks after the inoculation with a 0-4 symptoms scale. The differences were observed in the symptoms in the collection evaluated, with the disease severity index of the genotypes ranging from 0.00 to 4.00. While 31 genotypes displayed no symptoms, three cultivated eggplant genotypes were highly susceptible. Reciprocal F1 and F2 generations were obtained from the crosses between the most susceptible genotype (CT30) and a resistant one (CT49). The genetic control of the resistance adjusted well to one dominant and one recessive gene model underlying the resistance to Cmm. These results are important for selection and breeding for resistance to Cmm in eggplants.

Sixteen bacterial strains showing oval, convex with a white colony colour were obtained from the water-soaked lesions on the petioles and leaves of infected papaya (cv. calina) collected from a papaya field in Lampung Timur, Indonesia. The pathogenicity test showed that all the strains produced the same symptoms with those found in the field. Four representative strains were then chosen for further investigation. The phenotypic characteristics revealed that the strains resembled Erwinia mallotivora. Two representative strains were further identified using a 16SrDNA sequence analysis. The result showed that the strains were placed within the group of the type strain and the reference strains of E. mallotivora. To the best of our knowledge, this is the first finding of E. mallotivora as the causal agent of papaya crown rot disease in Indonesia. Among the sixteen plants used for the host range test, the symptom was only observed on eggplants, but not on the other fifteen plant species.

Glycosphingolipids in filamentous fungi are significant components of the plasma membrane and are vital for different cellular processes, such as growth, morphological transition or signal transduction. Fungal growth inhibitors targeting glycosylinositolphosphoceramide (GIPCs) biosynthesis or antifungal compounds binding to GIPCs present in membranes could present a safe way of preventing fungal growth on crops since GIPCs are not present in mammalian cells. Mass spectrometry-based shotgun lipidomics was used to analyze sphingolipids of 11 fungal strains isolated from plant material. Molecular species with inositol ceramides containing zero to five carbohydrates were identified. Differences in the amount of individual molecular species were influenced by the taxonomic affiliation. All tested strains exhibited a relatively high content (more than 40 mol.%) of GIPCs with three and more saccharides attached to the polar head. It could be assumed that the sphingolipid profiles of the tested plant pathogens would be an adaptation mechanism to antifungal plant defensins.

Soil-borne pathogens such as Verticillium species, invade into the roots of many herbaceous and woody hosts. The xylem environment supplies these pathogens with a continuous flow of nitrogen-rich nutrition. Detailed quantitative increases in amino acids in the stems, petioles, leaflets and roots of young tomato plants infected with Verticillium. albo-atrum the causal agent of wilt disease, are described in this paper for the first time. Results focus in particular on the vascular environment prior to the emergence of visual symptoms. Total amino acid concentrations in infected stems and petioles increased substantially at 144 and 216 h after inoculation. This effect was evident in leaflets at 216 h after inoculation. By 216 h most amino acid concentrations were substantially increased in stems, petioles and leaflets of infected plants relative to healthy controls. Earlier at 144 h in stems substantial increases were recorded for aspartic acid, threonine, serine, glutamic acid, glycine and ethanolamine. A similar picture emerged for petioles with the addition of increases in proline but not glycine. Amino acids increasing substantially in infected leaflets at 216 h were aspartic acid, glutamic acid and ethanolamine. In the infected roots there was relatively little difference in amino acid concentrations relative to healthy controls with the particular exceptions of proline and ethanolamine. By 18 days (432h), when visual symptoms were well advanced marked increases in amino acid concentrations were found for threonine, serine, α-alanine, valine, methionine, iso-leucine, leucine, tyrosine, ethanolamine, ornithine, lysine, histidine and arginine.

Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae) is a polyphagous moth species that mainly damages various crops and ornamental plants. This widely distributed pest is particularly a nuisance in Pakistan where it damages many crops, e.g., wheat and vegetables. To assess the risk of damage by this moth, we used the CLIMEX model to predict the distribution of A. ipsilon under current and future climatic conditions. Using the literature data, we collected information on the biology and ecology of A. ipsilon relevant for modelling the distribution of this species in Pakistan and worldwide under current and future climatic conditions. Our results revealed that under future climatic scenarios, the highly favourable habitat area of A. ipsilon (ecoclimatic index EI > 30) would decrease globally from 19% at present to 14% in the future, and the moderately favourable habitat area (0 < EI ≤ 15) would increase from 21 to 29%. We found that the northern areas of Pakistan will become highly suitable for the establishment of A. ipsilon. Under the current climatic conditions, the optimal habitats of A. ipsilon (EI > 30) comprised 10% and moderately favourable habitats (EI < 17) accounted for 25% of the total land area in Pakistan. Under future climatic scenarios, the optimal habitat area of the moth in Pakistan could decrease to 5% and the moderately favourable habitat area could cover 63% of the entire land area. The results can be applied in the protection of various crops and ornamental plants against A. ipsilon in Pakistan as well as worldwide.

Native species form a substantial part of arable weed communities. The objective of this survey was to study the occurrence of native species in arable fields in the Czech Republic related to applied management systems (conventional and organic farming), crops (winter cereals, spring cereals, wide-row crops) and environmental conditions at different altitudes. In 2006-2018, a phytocoenological survey (320 relevés) was performed across the Czech Republic. In total, 180 weed species were recorded, of which 43.33% were considered as native (78 species). The net effects of all the studied variables on the occurrence of native species were found as statistically significant. Most of the variability was explained by the altitude, followed by the crop and type of farming. The highest occurrence of native weeds was noticed in organic farming and cereals and increased with an increasing altitude. The higher incidence in higher elevations can be connected to the more intensive agriculture in the lowlands.

Wheat streak mosaic virus (WSMV) is a serious and widespread pathogen in the wheat-producing areas in the USA while, in Europe, it has been considered a minor threat to cereal crops. In the past, WSMV was detected in wheat, triticale and maize plants in Poland by DAS-ELISA. Here, we present the biological and molecular characterisation of WSMV-Sze and WSMV-Sosn isolates collected from western and southern Poland and report their transmissibility by the widespread wheat curl mite (WCM) lineage MT-8. The performed bioassays revealed that the analysed WSMV isolates infect wheat, barley, triticale, rye, oat and maize, but they differ in the symptoms induced on the infected plants. Moreover, they infect Bromus hordeaceus Linnaeus, which is increasingly recognised as a virus reservoir. The full-length genome sequence of both isolates was obtained and compared with the others described to date. The phylogenetic analysis revealed that the Polish isolates are clustered with the earlier described type B isolates of WSMV from Europe and Iran. The recombination analysis revealed the presence of recombinant variants in WSMV population and indicated that the WSMV-Sosn might originated from the intra-species recombination of the WSMV-Sze and WSMV-Cz isolates.

The natural occurrence of 'Candidatus Phytoplasma trifolii' in pear trees (Pyrus communis Linnaeus) is reported here for the first time. In 2017, a total of thirty-five pear trees, two of them exhibiting leaf rolling along the midvein, reddening, bushy appearance, and upright growth symptoms were sampled in different locations in Van province, Turkey. The total deoxyribonucleic acid was extracted from symptomatic and asymptomatic plants. The purified DNA served as a template in nested polymerase chain reaction (nested-PCR) assays, performed to amplify 16S rRNA sequences using universal primer pairs (R16mF2/R16mR1 and R16F2n/R16R2). The resulting PCR products were then cloned into a pGEM T-Easy vector and sequenced bidirectionally. The phytoplasma strain, group, and subgroup identity were determined using the in silico restriction fragment length polymorphism (RFLP) analysis of the 16S ribosomal RNA-encoding gene sequences profiling with seventeen distinct restriction enzymes. Of the thirty-five pear samples, only two yielded 1 256 bp and 1 258 bp DNA fragments and were designated as Van-Pr3 (Acc. No. MH709141) and Van-Pr4 (Acc. No. MH730561), respectively. Based on the in silico virtual RFLP pattern analysis of the 16S rRNA sequences, we confirmed the presence of 'Ca. P. trifolii' belonging to the clover proliferation group and both identified phytoplasmas were identical with the similarity coefficient of 1.00 to the reference pattern of 16Sr group VI, subgroup A (Acc. No. AY390261). Here we report that the pear tree is an alternate host of the 'Ca. P. trifolii'.

In Taiwan, numerous crops are threatened by Xanthomonas diseases such as citrus bacterial canker caused by X. citri subsp. citri and tomato bacterial spot mainly caused by X. euvesicatoria pv. perforans. Foliar sprays of copper-based bactericides have been frequently used for control of plant bacterial diseases. However, in Taiwan not much attention was paid on copper-resistant (Cu^R) Xanthomonas spp. and their impact on disease control efficacy of copper-based bactericides. In this study, Cu^R Xanthomonas isolates were collected from citrus and tomato in Taiwan. Compared with the pronounced effect on the copper sensitive isolate, spraying of copper hydroxide at the recommended rate of 0.5 kg/ha could not protect tomato plants against bacterial spot caused by the Cu^R isolate. Phylogenetic analysis of concatenated copper resistance genes, copL, copA, and copB, indicate that the Taiwanese Cu^R isolates belong to the worldwide clade. In addition to the three previously reported variants of the copB gene, analysis of complete copB sequences from xanthomonads associated with citrus and solanaceous hosts revealed the other three variants of copB and their global distribution. Copper-resistant Xanthomonas isolates from Taiwan have the two unreported variants of copB genes which differ from the other three previously reported types in the sizes and structures. The information provided here reveals the necessity to develop and include alternative measures rather than relying on foliar sprays of copper bactericides for sustainable control of tomato bacterial spot in Taiwan.

The study aimed to evaluate the efficacy of a seed film coating with Origanum vulgare Linnaeus essential oil (EO) against Clavibacter michiganensis subsp. michiganensis (Cmm) on tomatoes. Tomato seeds (cv. Rio Grande) coated with different doses of EO derived from O. vulgare were inoculated with Cmm (1.8 × 10⁸ CFU/mL). O. vulgare's EO showed a remarkable inhibition effect on the Cmm growth. The EO effect against Cmm was determined based on the parameters, such as the inhibition zone and bacterial population in a seed. The GC-MS analysis of EO showed that carvacrol is the major component (at 74.05%), which may inhibit the bacterial growth. Later, we have expanded our studies to determine the inhibitory effect of the EO's mode of action on the pathogenic bacteria with a molecular docking analysis based on the molecular protein-ligand interaction. The results showed that carvacrol has a strong interaction with the bacterial expansin protein (PDB 4JJO) of Cmm and the qPCR analyses confirmed the effect of the O. vulgare treatment against Cmm. This original approach has the prominent potential to prevent seed transmission of Cmm for seed quality in the world, suggesting a method for paving the way for Cmm disease management.

Leaf stripe is a common, but major infectious disease of barley, severely affecting the yield and quality. However, only a few genes have been identified by conventional gene mapping. Gene family analysis has become a fast and efficient strategy for gene discovery. Studies demonstrated that Argonaute (AGO) proteins play an important role in plant disease resistance. Thus, we obtained nine HvAGO genes via mRNA sequencing before and after a Pyrenophora graminea infection of a disease-resistant variety "Kunlun 14" and a susceptible variety "Z1141". We analysed the physicochemical characteristics, gene structures, and motifs of the HvAGO gene sequences and found that these proteins were divided into four clusters by evolutionary distance. There was high consistency in the number of exons, size, and the number and type of motifs in the different clusters. Based on protein phylogenetics, they could be divided into three branches. A collinearity analysis of Tibetan hull-less barley and Arabidopsis thaliana, rice, and maize showed that four genes were collinear with respect to the other three species. The qRT-PCR showed the expression levels of HvAGO1, HvAGO2 and HvAGO4 were significantly increased after infection with Pyrenophora graminea. These three members of the AGO gene family are, thus, speculated to play an important role in barley leaf stripe resistance. The results provide reference for the application of HvAGO genes in the leaf stripe control and the exploration of disease resistance genes in other crops.

The complete nucleotide sequence of Zucchini yellow mosaic virus isolate from Egypt (ZYMV-Egz_MT383108) was determined. The sequence comparisons suggested that the isolate belongs to Group A. The sequence analysis of the Egyptian isolate showed the highest similarity (~96-97%) with the isolates leaf1 (KJ923767.1) and PA_2006 (JQ716413.1) from the USA and the lowest similarity (84%) with an isolate (AF014811.2) from Singapore. The phylogenetic analysis revealed that ZYMV-Egz occupied a distinct clade together with the USA isolates in Group A, known to be the most widespread throughout the world. This is a first record of the complete nucleotide sequence of an Egyptian isolate of ZYMV.

This study evaluated the toxicity and repellent activities of essential oils (EOs) against Sitophilus granarius (Linnaeus, 1758), both in vitro and in vivo conditions. The EOs obtained from Thymus pallescens Noë. (Lamiaceae) and Cymbopogon citratus Stapf. (Poaceae) were analyzed by GC-MS, and revealed that carvacrol (56.64%) and geraniol (20.8%) as the respective major components. T. pallescens EO was found to be a more effective toxicant, with LC₅₀ and LC₉₀ values of 9.3 and 34.6 µL/mL, respectively, in the contact test vs 8.2 and 25.3 µL/mL in the fumigation test. T. pallescens EO showed also a stronger repellent effect with values ranging from 83.4% to 100%. In the in vivo test, the survival probability decreased from 99.9 to 2.48% among insects exposed to T. pallescens EO. These data demonstrated that EOs could be considered effective alternatives to chemical insecticides, providing pest control for stored products in an ecologically sustainable manner.

In this study, the population growth parameters of Aphis gossypii Glover (Hemiptera: Aphididae) on five different melons [Cucumis melo Linnaeus (Cucurbitaceae) cultivars (Balin, Çitirex, 221 F1, Gediz, Yusufbey)], which are commonly grown in Turkey, were investigated in laboratory experiments. Life table parameters were estimated according to age-stage and two-sex life table theory. The results showed that A. gossypii developed more successfully on the Gediz cultivar due to the higher intrinsic rate of increase (0.5042 1/day), the finite rate of increase (1.6557 1/day), and the shorter mean generation time (8.161 days) than the other cultivars. Ecological pest control against aphids' use of resistance or less favorable host plant cultivars is considered one of the significant components of pest management. The findings obtained in this study can be used in the pest management program designed for the aphid.

Cacopsylla pyri (Linnaeus, 1758) is the most significant and widespread pear pest. It attacks the pear only, causing direct and indirect damages. This study was conducted in order to evaluate the efficacy of insecticide spinetoram in the control of C. pyri. The experiment was set up according to EPPO methods, at the locality Kula (Republic of Serbia) in a pear orchard (Williams variety). Spinetoram (250 g/kg a.i., WG) was foliar applied in the amount of 0.3 kg/ha, during overlapping pest generations, when pear was on BBCH 75 scale. The efficacy was evaluated through the number of larvae aged L₁-L₃ and L₄-L₅. Spinetoram has shown satisfying efficacy, especially in the control of L₁-L₃ larvae (81.6%). In a dissipation study, spinetoram residues in pear fruits were determined using QuEChERS method followed by HPLC-DAD. The method was validated to fulfill SANTE/12682/2019 criteria. Three days after the application, spinetoram residues in pear fruits were below the MRL (0.2 mg/kg). The results have shown that spinetoram dissipation pattern followed the first-order kinetics (R² = 0.979) with a half-life of 2.17 days, in pear fruits. This study suggests that spinetoram could be safely used in pear, and it could take an important place in insecticide resistance management.

The content of free, conjugated and bound phenolic acids in 12 wheat (Triticum aestivum L.) genotypes of 4 different grain colours (standard red, yellow endosperm, purple pericarp and blue aleurone) from 2-year field trial was analysed in the present study. Significant increase (8%) in the total phenolic acid content was observed in the dryer year 2017. Five phenolic acids (ferulic, sinapic, p-coumaric, vanillic and 4-hydroxybenzoic) and cis-isomers of ferulic and sinapic acid were determined by HPLC-DAD (high-performance liquid chromatography with a diode-array detector) in grain samples. The total phenolic acid content of coloured wheat groups varied: blue aleurone > purple pericarp > yellow endosperm > red colour (798 > 702 > 693 > 599 µg/g). The fraction of bound phenolic acids was the major contributor to the total phenolic acid content (91.7%) with ferulic acid predominating (85.2%). Conjugated phenolic acids accounted for 7.9% of the total with sinapic and ferulic acid predominating (47.6% and 19.9%). The composition of individual phenolic acids was similar within these two fractions. The remaining 0.4% was represented by the fraction of free phenolic acids in which the phenolic acid profile varied among the individual coloured groups. Ferulic acid prevailed in red and yellow wheats, vanillic in blue and p-coumaric in purple wheats.

Glomalin released from arbuscular mycorrhizal fungi (AMF) has important roles in soil nutrient cycles, whereas contributing to glomalin-related soil protein (GRSP) fractions to soil nitrogen (N) is unknown. In this study, a two-chambered root-box that was divided into root chamber (root and mycorrhizal fungi hypha) and hypha chamber (free of the root) was used, and three AMF species including Diversispora epigaea, Paraglomus occultum, and Rhizoglomus intraradices were separately inoculated into the root chamber. Plant growth, soil total N, N content of purified GRSP fractions, and its contribution to soil total N, and leaf and root N contents were analysed. After four months, total biomass and root total length, surface area, and volume were improved by all AMF inoculations. AMF inoculations dramatically increased soil total N content in two chambers. The N content of purified easily extractable GRSP (EE-GRSP) and difficultly extractable GRSP (DE-GRSP) was 0.10 ± 0.01 mg/g and 0.16 ± 0.02 mg/g, respectively, accounted for 15.6 ± 1.6% and 18.1 ± 1.8% of soil total N, respectively. AMF inoculations stimulated the N accumulation in EE-GRSP and DE-GRSP, especially in the hypha chamber. It concluded that GRSP, especially DE-GRSP, acts as a soil N pool accounting for 33.8 ± 1.9% of soil total N in orchards.

Previous studies have shown that residues of common buckwheat roots (BRR) (but not entire common buckwheat plants, BPR) in the soil inhibited the growth of barnyardgrass (Echinochloa crus-galli L.). The objective of the study was to determine how both the residues affect the content of free phenolics, their esters and glycosides in the soil. The aqueous extracts were used to analyse of unbound phenolic compounds, while those bound to the soil were extracted with sodium citrate. Moreover, an in vitro test was used to assess the allelopathic effect of phenolic compounds present in the soil against barnyardgrass. Among the analysed phenolic compounds after 7 days of BPR and BRR decomposition, only ortho-, meta- and para-coumaric acids and apigenin were found in measurable amounts in the soil. The concentrations of free phenolic compounds were very low. Much higher contents occurred for the esters of these compounds, while no glycosides were found. The contents of phenolic compounds bound to soil were many times higher than unbound ones. The 37-day decomposition period resulted in an increase in bound phenolics, while the content of unbound changed slightly. Overall, the levels of phenolic compounds in the soil with the BRR-amended soil and no-buckwheat residue control were low, and significantly higher in the soil with BPR. An in vitro test showed that m-, p-coumaric acids and apigenin added to growth medium at a concentration higher than in the soil did not affect barnyardgrass shoot growth. Since the levels of phenolic compounds in the soil containing BRR and control soil were low and similar, phenolic compounds cannot be directly responsible for the allelopathic properties caused by the presence of BRR.

Labile carbon (C) is a major source of C loss because of its high vulnerability to environmental change. Yet its potential role in regulating soil organic carbon (SOC) dynamics remains unclear. In this study, we tested the effect of physical disturbance on SOC decomposition using soils from two abandoned farmlands free of management practice for more than 28 years. The soil respiration rate was measured in undisturbed and disturbed soil columns and was inversely modeled using the two-compartment model. We found that the C loss was 16.8~74.1% higher in disturbed than in undisturbed soil columns. Physical disturbance increased the total amount of labile C (C₁) loss by 136~241%, while had no effect on the kinetic decomposition rate constants of both labile (k₁) and stable (k₂) SOC decomposition. Physical disturbance fragmented the large macroaggregates into small macroaggregates, microaggregates, and free silt and clay-sized fractions. This indicates that C loss was derived from the initially protected labile C, and there was no change of SOC fraction being decomposed. Our results give insights into the understanding of the extent of labile C loss to physical disruption and demonstrate the potential effect of physical disturbance on SOC dynamics.