Hypocrealean fungi associated with populations of <Emphasis Type="Italic">Ips typographus</Emphasis> in West Carpathians and selection of local <Emphasis Type="Italic">Beauveria</Emphasis> strains for effective bark beetle control

In Slovakia, a diversity of entomopathogenic fungi (Ascomycota, Hypocreales) associated with outbreaks of Ips typographus was studied in 81 localities and as many as 113 in vitro cultures of five entomopathogenic species were isolated from infected individuals: Beauveria bassiana (87 isolates), B. pseudobassiana (14 isolates), B. caledonica (6 isolates), Lecanicillium lecanii (4 isolates) and Isaria farinosa (2 isolates). B. pseudobassiana is recorded in natural populations of I. typographus for the first time. Biological properties of selected Beauveria isolates, including colony growth, biomass production, conidia yield and pathogenicity to I. typographus adults, were studied in a series of laboratory bioassays and much intra- and interspecific variability was detected. B. bassiana isolates produced biomass or conidia at significantly higher rate than B. pseudobassiana and B. caledonica isolates. Two B. bassiana isolates were selected as the most virulent to bark beetle adults, demonstrating a mean LC₅₀ ranging from 0.72 to 2.05?×?10⁶ conidia ml^?1, and were qualified as promising candidates for biocontrol of I. typographus. Their virulence was significantly higher than that of the mycoinsecticides Boverol®, which was used as a reference strain in the virulence bioassays.     

Acute Toxicity of Fresh and Aged Residues of Pesticides to the Parasitoid <Emphasis Type="Italic">Tamarixia radiata</Emphasis> and to the HLB-Bacteria Vector <Emphasis Type="Italic">Diaphorina citri</Emphasis>

One method for controlling the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama, the vector of the putative causal agent of Huanglongbing, uses the parasitoid Tamarixia radiata (Waterston). However, the general intensive use of insecticides has reduced the numbers of this parasitoid. This study evaluated the effect of the residual action of 24 insecticides on T. radiata and also determined the differential toxicity of insecticides to D. citri and T. radiata, using three bioassays. In the first, when adults of the parasitoid were exposed to residues of the 24 insecticides, ten were considered short-life (class 1), six slightly persistent (class 2), five moderately persistent (class 3), and three insecticides were considered persistent (class 4), under the IOBC/WPRS classification system. The second bioassay evaluated the sublethal concentrations of the persistent insecticides (formetanate, dimethoate, spinosad). Increasing the concentrations of the insecticides increased the number that were classified as persistent. In the third bioassay, evaluation of the differential toxicity of eight insecticides to the ACP and the parasitoid showed that chlorpyrifos and bifenthrin were more harmful to T. radiata. Therefore, these two insecticides are not recommended for application at the time of parasitoid release. Cypermethrin, imidacloprid, and dimethoate caused higher mortality of D. citri and are most often recommended in IPM programs. The choice of an insecticide for the control of citrus pests must be made with care, aiming to preserve the natural enemies in the ecosystem, and thereby contribute to the success of biological control.     

Acaricidal active fractions from acetone extract of <Emphasis Type="Italic">Aloe vera</Emphasis> L. against <Emphasis Type="Italic">Tetranychus cinnabarinus</Emphasis> and <Emphasis Type="Italic">Panonychus citri</Emphasis>

This study aimed to isolate acaricidal active fractions from acetone extract of Aloe vera L. and investigate the toxicity of these fractions against Tetranychus cinnabarinus (T. cinnabarinus) and Panonychus citri (P. citri). Acetone extract of A. vera L. was isolated by immersing in acetone for 72 h, and diverse fractions were fractionated by column chromatography. The acaricidal activity of each fractions was evaluated by corrected mortality of T. cinnabarinus through slide-dip bioassay. The 8th and 13th fractions of acetone extract with good acaricidal activity were indentified by LC/MS, and the toxicity of these two fractions to T. cinnabarinus and P. citri was identified by regression analysis. Acetone extract of A. vera L. exhibited obvious acaricidal activity, from which a total of 18 fractions were isolated. The 8th and 13th fractions with strong acaricidal activity against T. cinnabarinus were identified to be 3-O-alpha-d-mannopyranosyl-d-mannopyranose (OAMM) and aloe emodin. When compared with spirodiclofen, both OAMM and aloe emodin exhibited higher toxicity to T. cinnabarinus, while only OAMM exhibited a higher toxicity to P. citri (P < 0.05). OAMM and aloe emodin isolated from acetone extract of A. vera L. exhibited obvious acaricidal activities against T. cinnabarinus and P. citri.     

The fitness of the cotton mealybug <Emphasis Type="Italic">Phenacoccus solenopsis</Emphasis> (Tinsley) is reduced after feeding on virus-infected <Emphasis Type="Italic">Hibiscus rosa</Emphasis>-<Emphasis Type="Italic">sinensis</Emphasis>

The cotton mealybug Phenacoccus solenopsis (Tinsley) and Cotton leaf curl Multan virus (CLCuMV), serious threats to economic crops and garden plants, have invaded southern China and widely infected Hibiscus rosa-sinensis. Whether an inter-species connection has facilitated the invasion process is unclear. In this study the interaction between P. solenopsis and H. rosa-sinensis infected with CLCuMV was investigated in the laboratory. We observed that 1st and 2nd instar nymphs of P. solenopsis preferred to feed on healthy H. rosa-sinensis leaves, whereas 3rd instar nymphs and female adults had no preference between healthy and virus-infected H. rosa-sinensis leaves. The developmental time of each P. solenopsis developmental stage increased significantly after feeding on infected H. rosa-sinensis leaves (p < 0.05). In particular, the development time for 2nd instar female and male nymphs and 3rd instar female nymphs increased by approximately twofold. The generation time of female mealybugs increased from 25.84 d on healthy H. rosa-sinensis to 32.12 d when feeding on CLCuMV-infected H. rosa-sinensis, and the survival rate decreased from 71.04 % on healthy H. rosa-sinensis to 5.80 % on infected plants. Nymph survival was most affected by feeding on infected plants. Additionally, the fecundity of female mealybugs feeding on infected H. rosa-sinensis decreased by 47.8 %. Thus, feeding on CLCuMV-infected H. rosa-sinensis significantly decreased the biological fitness and invading and colonizing abilities of P. solenopsis.     

<Emphasis Type="Italic">Diplazium</Emphasis> hybrids involving <Emphasis Type="Italic">D. plantaginifolium</Emphasis> and <Emphasis Type="Italic">D</Emphasis>. <Emphasis Type="Italic">ternatum</Emphasis> from Mexico and Central America

Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.     

Trail Chemicals of the Convergens Ladybird Beetle, <Emphasis Type="Italic">Hippodamia convergens</Emphasis>, Reduce Feeding and Oviposition by <Emphasis Type="Italic">Diaphorina citri</Emphasis> (Hemiptera: Psyllidae) on Citrus Plants

We investigated feeding and oviposition behavior of the Asian citrus psyllid, Diaphorina citri, when exposed to the foraging trails of the convergens ladybird beetle, Hippodamia convergens. Diaphorina citri females feeding on citrus leaves directly exposed to the ladybird adults or treated with trail extract excreted significantly less honeydew droplets than controls. The trail chemicals of the ladybird beetle also decreased oviposition by D. citri females on citrus. In a no-choice experiment, D. citri females preferred to oviposit on control flush and plants than those with ladybird trail-extract treatments. In two-choice experiments, 68.0% of D. citri released into cages exhibited strong selection preference for settling and eventual oviposition on control plants than plants treated with ladybird trail extract. Diaphorina citri eggs were found on all new leaf flush of control plants, whereas only 29.5% of flush on treatment plants were selected for oviposition. The trail chemical deposited by the convergens ladybird beetle elicits repellency of D. citri feeding and oviposition. Therefore, the trail chemicals my contain components that could be useful for behavior-based management of D. citri and HLB disease by reducing psyllid feeding and oviposition.     

Detection of <Emphasis Type="Italic">Diaphorina citri</Emphasis> Kuwayama (Hemiptera: Liviidae) in Kenya and potential implication for the spread of Huanglongbing disease in East Africa

The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae) is a damaging pest of citrus globally and has recently been detected in Tanzania. Although direct damage by the pest is seldom of economic importance, the insect is more notorious for its ability to vector the fastidious phloem-limited bacterium Candidatus Liberibacter asiaticus (CLas), the putative causal bacterium of Huanglongbing or Asian citrus greening disease. For many years, Trioza erytreae (Del Guercio) (Hemiptera: Triozidae) was known to be the main vector of the African citrus greening disease caused by Candidatus Liberibacter africanus (CLaf), but the recent arrival of D. citri on the continent adds to the dynamics of infection and spread of both diseases on mainland Africa. Following the recent report of the presence of D. citri in Tanzania, an additional delimiting survey was carried out in the region, focusing on Kenya, mainland Tanzania and Zanzibar to detect the presence and ascertain the extent of spread of D. citri. We employed molecular tools based on the use of DNA barcoding to confirm the identity of D. citri. In addition to D. citri, the occurrence of T. erytreae in the same sampling locations is also reported. Adults and nymphs of either D. citri or T. erytreae were collected from citrus at many of the surveyed sites ranging from 19 to 668 m above sea level (masl) in Tanzania, 20–1666 masl in Kenya, and 42–48 masl in Zanzibar. Diaphorina citri was sympatric with T. erytreae at the mid to higher elevations of 1375–1666 masl and no T. erytreae or its open-gall symptoms were detected below 523 masl. Sequences obtained were queried via BLAST and all linked to D. citri of different accession numbers already available on GenBank. This is the first report of the presence of D. citri in Kenya and Zanzibar. The potential implication of the detection and spread of the two pathogens, CLaf and CLas to the citrus industry in East Africa and movement of suitable host plants is discussed.     

Virulence of the entomopathogenic fungus <Emphasis Type="Italic">Metarhizium anisopliae</Emphasis> using soybean oil formulation for control of the cotton stainer bug, <Emphasis Type="Italic">Dysdercus peruvianus</Emphasis>

The cotton stainer bug Dysdercus peruvianus (Hemiptera: Pyrrhocoridae) is an insect pest that causes heavy losses in cotton plantations. The need to reduce the use of insecticides for control of this pest has increased steadily, and Metarhizium anisopliae (Ascomycota: Clavicipitaceae) could be an important biopesticide candidate to control this pest. The effect of M. anisopliae on D. peruvianus nymphs and adults using formulations with soybean oil and Agral^® was evaluated. Formulation using 10% soybean oil added to 10⁸ conidia mL^?1 (grown on used and reused rice) was the most effective for nymph and adult, causing 100% mortality 6 and 7 days after exposure, respectively. The SEM analysis of infected insects showed that M. anisopliae conidia were able to adhere anywhere on the exoskeleton, but were more abundant between the joints. Using the same rice for two batches of growth may be an option for improving commercial conidial production of M. anisopliae and may reduce overall costs. Its effect on D. peruvianus adults opens a new possibility for using this fungus as an alternative to chemical pesticides and the use of M. anisopliae in association with integrate pest management.     

Susceptibility of Asian citrus psyllid, <Emphasis Type="Italic">Diaphorina citri</Emphasis> (Hemiptera: Liviidae), to the insecticide afidopyropen: a new and potent modulator of insect transient receptor potential channels

A relatively new insecticide chemistry for controlling sucking insects, afidopyropen, was investigated for toxicity against Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). We evaluated the mortality of D. citri eggs, nymphs, and adults treated with afidopyropen using both laboratory-reared and field populations. We also quantified the effects of sublethal doses of afidopyropen on D. citri feeding, host choice selection, and fecundity. For laboratory susceptible adults, the contact LC₅₀, topical application LD₅₀, and leaf dip LC₅₀ were 2.13, 2.00, and 3.08 ng/µL, respectively. For adults collected from a commercially managed citrus grove in Florida, the contact LC₅₀, topical application LD₅₀, and leaf dip LC₅₀ were 1.37, 1.92, and 4.89 ng/µL, respectively. Egg hatch was significantly reduced following exposure to afidopyropen at 100 ng/µL. Furthermore, afidopyropen reduced D. citri nymph survival and adult emergence at concentrations ranging between 0.01 and 100 ng/µL. Diaphorina citri adult feeding decreased on citrus leaves treated with afidopyropen in a concentration-dependent manner as measured indirectly by honeydew excretion, and appeared almost completely inhibited after treatment with 10 and 100 ng/µL solutions of afidopyropen. In choice tests, significantly fewer D. citri adults settled on afidopyropen-treated plants than on control plants at 24, 48, and 72 h after release, with no differences in settling between males and females. Afidopyropen reduced the fecundity of D. citri in a concentration-dependent manner. Collectively, the results suggest that afidopyropen could contribute to the integrated management of D. citri and may therefore be useful in rotational programs to improve resistance management.     

Toxin Gene Contents and Activity of <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis> Strains Against Two Sugarcane Borer Species, <Emphasis Type="Italic">Diatraea saccharalis</Emphasis> (F.) and <Emphasis Type="Italic">D. flavipennella</Emphasis> (Box)

Bacillus thuringiensis (Berliner) bears essential characteristics in the control of insect pests, such as its unique mode of action, which confers specificity and selectivity. This study assessed cry gene contents from Bt strains and their entomotoxicity against Diatraea saccharalis (F.) and Diatraea flavipennella (Box) (Lepidoptera: Crambidae). Bioassays with Bt strains were performed against neonates to evaluate their lethal and sublethal activities and were further analyzed by PCR, using primers to identify toxin genes. For D. saccharalis and D. flavipennella, 16 and 18 strains showed over 30% larval mortality in the 7th day, respectively. The LC₅₀ values of strains for D. saccharalis varied from 0.08 × 10⁵ (LIIT-0105) to 4104 × 10⁵ (LIIT-2707) spores + crystals mL^?1. For D. flavipennella, the LC₅₀ values of strains varied from 0.40 × 10⁵ (LIIT-2707) to 542 × 10⁵ (LIIT-2109) spores + crystals mL^?1. For the LIIT-0105 strain, which was the most toxic to D. saccharalis, the genes cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, cry8, and cry9C were detected, whereas for the strain LIIT-2707, which was the most toxic to D. flavipennella, detected genes were cry1Aa, cry1Ab, cry1Ac, cry1B, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, and cry9. The toxicity data and toxin gene content in these strains of Bt suggest a great variability of activity with potential to be used in the development of novel biopesticides or as source of resistance genes that can be expressed in plants to control pests.     

Grapevine leaf tissue colonization by the fungal entomopathogen <Emphasis Type="Italic">Beauveria bassiana</Emphasis><Emphasis Type="Italic">s.l.</Emphasis> and its effect against downy mildew

A study was conducted to examine whether Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) can colonize grapevine leaf tissues and subsequently confer protection against downy mildew caused by Plasmopara viticola (Berk. and Curt.) Berl. and de Toni. Following the foliar inoculation of plants with conidial suspensions of selected B. bassiana strains, colonization of leaves by the fungus was determined using culture-based and PCR techniques at different time intervals. Seven days following B. bassiana inoculation, grapevine plants were challenged with P. viticola and symptoms were assessed by calculating the disease incidence and severity. Although all tested strains were able to colonize grapevine plants, percent colonization differed significantly among strains. Disease incidence and severity were, on the other hand, significantly reduced in B. bassiana-inoculated plants compared to control plants irrespective of strain. This study is one of very few studies investigating the promising role B. bassiana could play as a plant disease antagonist.     

Impact of Chemical,Organic and Bio-Fertilizers Application on Bell Pepper, <Emphasis Type="Italic">Capsicum annuum</Emphasis> L. and Biological Parameters of <Emphasis Type="Italic">Myzus persicae</Emphasis> (Sulzer) (Hem.: Aphididae)

Myzus persicae (Sulzer) is a polyphagous aphid that causes chlorosis, necrosis, stunting, and reduce growth rate of the host plants. In this research, the effects of Zinc sulfate and vermicompost (30%), Bacillus subtilis, Pseudomonas fluorescens, Glomus intraradices, G. intraradices × B. subtilis, and G. intraradices × P. fluorescens compared to control was investigated on the growth characters of Capsicum annuum L. and biological parameters of M. persicae. Different fertilizers caused a significant effect on growth characters of C. annuum and biological parameters of M. persicae. The highest plant growth was observed on Zinc sulfate and B. subtilis treated plants, and the lowest was on control. Increase in the amount of specific leaf area (SLA) (0.502 mm² mg^?1) was significantly higher in the B. subtilis than other fertilizer treatments. The longest (10.3 days) and the shortest (5.3 days) developmental times of M. persicae nymphs were observed on 30% vermicompost and Zinc sulfate treatments, respectively. The lowest adult longevity periods of M. persicae (11.2 and 11.3 days) were observed on G. intraradices × B. subtilis and 30% vermicompost treatments, respectively, and the longest ones (16.4 days) on Zinc sulfate. The highest rate of nymphal mortality and the lowest amount of nymphal growth index (NGI) were recorded on 30% vermicompost. The nymphs reared on Zinc sulfate treatment had the lowest rate of nymphal mortality and the highest amount of NGI. Thus, amending the soil with 30% vermicompost had a significantly negative effect on the biological parameters of M. persicae that can be used as an ecological control tactic for this pest.     

Seasonal and yearly change in adult abundance of a predacious ladybird <Emphasis Type="Italic">Serangium japonicum</Emphasis> (Coleoptera: Coccinellidae) and the citrus whitefly <Emphasis Type="Italic">Dialeurodes citri</Emphasis> (Hemiptera: Aleyrodidae) in citrus groves

Serangium japonicum Chapin (Coleoptera: Coccinellidae) chiefly attacks whiteflies. This study monitored the adult occurrence of the ladybird and the citrus whitefly Dialeurodes citri (Ashmead) (Hemiptera: Aleyrodidae) in citrus groves in central Japan using sticky traps, thereby examining temporal relationships in their abundance. Many S. japonicum adults were captured in a pesticide-free grove where D. citri adults were very abundant, with few adults in neighboring (organic, reduced pesticide, and conventional) groves harboring small numbers of D. citri. The whitefly adults exhibited a large peak in numbers in late May to early June. Two peaks of the ladybird adult numbers were detected in late May to early June and late June to mid-July, ?6 to 7 days, and nearly 1 month after the peak in whitefly adult numbers, respectively. The ladybird adults found during the first peak period would be those that visited citrus trees mainly for oviposition, and the adults caught during the second peak period would be those that newly emerged after consuming immature whiteflies at the larval stage. Based on a yearly change in adult numbers in the pesticide-free grove, i.e., a large increase in S. japonicum numbers followed by a rapid decline in D. citri numbers, the ladybird’s role in controlling the whitefly is discussed.     

Soybean aphid, <Emphasis Type="Italic">Aphis glycines</Emphasis> (Hemiptera: Aphididae), developmental and reproductive capacity on white clover, <Emphasis Type="Italic">Trifolium repens</Emphasis> (Rosales: Leguminosae), in northeast China

Nymphs of Aphis glycines Matsumura were individually reared to adults in the laboratory on detached leaf discs of Trifolium repens L. (white clover) mounted on agar medium. Adults of A. glycines were fed T. repens within small clip cages in the field. Development, reproduction and intrinsic rates of increase of A. glycines were studied. These data were compared to those of controls fed known host plants including cultivated soybean Glycine max (L.) Merr. and the wild soybean species Glycine soja Sieb & Zucc. The results demonstrated that nymphs of A. glycines successfully developed into adults and reproduced efficiently when reared on T. repens in the laboratory. The lower development temperature threshold for nymphs fed T. repens was estimated as 8.27 °C, and the effective cumulative temperature for A. glycines development from nymph to adult was 90.91 degree-days. Adults of A. glycines could also survive on T. repens in the field, but only a few nymphs were produced.     

Acaricidal and repellent effects of <Emphasis Type="Italic">Cnidium officinale</Emphasis>-derived material against <Emphasis Type="Italic">Dermanyssus gallinae</Emphasis> (Acari: Dermanyssidae)

The acaricidal activity of a methanolic extract and fractions from the rhizome of Cnidium officinale against Dermanyssus gallinae adults was investigated. The C. officinale methanolic extract exhibited 100% acaricidal activity after 48 h of treatment at a dose of 4000 ppm. The acaricidal constituents of the plant were sequentially partitioned with several solvents and then purified using silica gel column chromatography and high-performance liquid chromatography. Gas chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy revealed (Z)-ligustilide as a constituent of C. officinale. Acaricidal activity was examined in three experimental tests (spray, fumigation and contact), with the spraying method being the most effective. The methanolic extract of C. officinale showed both contact and fumigant activities, though only fumigant activity was observed with (Z)-ligustilide. The fumigant effects of the methanolic extract and (Z)-ligustilide caused 86.5 and 62.6% mortality, respectively, of D. gallinae adults at 48 h. Among (Z)-ligustilide, acaricides (bifenthrin, cypermethrin and spinosad) and butylidenephthalide, bifenthrin displayed the highest acaricidal activity, and the activity of butylidenephthalide was 2.3-fold higher than that of (Z)-ligustilide. These results suggest that C. officinale-derived material can be used for the development of a control agent for D. gallinae.     

Endophytic <Emphasis Type="Italic">Alcaligenes</Emphasis> Isolated from Horticultural and Medicinal Crops Promotes Growth in Okra (<Emphasis Type="Italic">Abelmoschus</Emphasis><Emphasis Type="Italic">esculentus</Emphasis>)

The potential of endophytic bacteria to act as biofertilizers and bioprotectants has been demonstrated, and considerable progress has been made in explaining their role in plant protection. In the present study, three endophytic bacterial strains (BHU 12, BHU 16 isolated from the leaves of Abelmoschus esculentus, and BHU M7 isolated from the leaves of Andrographis paniculata) were used which displayed high sequence similarity to Alcaligenes faecalis. The biofilm formation ability of these endophytic strains in the presence of okra root exudates confirms their chemotactic ability, an initial step for successful endophytic colonization. Further, reinoculation of spontaneous rifampicin-tagged mutants into okra seedlings revealed a CFU count above 10⁵ cells g^?1 of all three endophytic strains in root samples during the first 15 days of plant growth. The CFU count increased up to 10¹³ by 30 days of plant growth, followed by a gradual decline to approximately 10¹⁰ cells g^?1 at 45 days of plant growth. Systemic endophytic colonization was further supported by 2, 3, 5-triphenyl tetrazolium chloride staining and fluorescence imaging of ds-RED expressing conjugants of the endophytic strains. The strains were further assessed for their plausible in vivo and in vitro plant growth-promoting and antagonistic abilities. Our results demonstrated that the endophytic strains BHU 12, BHU 16, and BHU M7 augmented plant biomass by greater than 40 %. Root and shoot lengths of okra plants when primed by BHU 12, BHU 16, and BHU M7 increased up to 34 and 14.5 %, respectively. The endophytic isolates also exhibited significant in vitro antagonistic potential against the collar rot pathogen Sclerotium rolfsii. In summary, our results demonstrate excellent potential of the three endophytic bacterial strains as biofertilizers and biocontrol agents, indicating the possibility for use in sustainable agriculture.     

Fungi isolated from insects in strawberry crops act as potential biological control agents of <Emphasis Type="Italic">Duponchelia fovealis</Emphasis> (Lepidoptera: Crambidae)

Entomopathogenic fungi were collected from insects, belonging to orders Lepidoptera, Coleoptera, Hemiptera, Hymenoptera, and Diptera, with signs of infection. Single-spore colonies were identified based on morphological traits and ribosomal ITS sequences. The most commonly found fungi were Fusarium oxysporum Schlechtendal and Beauveria bassiana (Balsamo-Crivelli) Vuillemin. Isolation of Trichoderma atroviride Bisset, Aspergillus flavipes (Bainier and Sartory) Thom and Church, Aspergillus iizukae Sugiyama, Penicillium mallochii Rivera, Urb and Seifert, Penicillium adametzioides S. Abe ex G. Smith, and Mucor nidicola Madden, Stchigel, Guarro and Starks associated to insects is reported for the first time. Tests with B. bassiana isolates against Duponchelia fovealis Zeller (Lepidoptera: Crambidae), showed high larval mortality in vitro and in greenhouse, demonstrating its potential as biological control agent. Understanding the fungal microbiota from insects can provide promising isolates for use in integrated pest management programs. This is the first report characterizing the mycobiota in insects collected in strawberry crops, and evaluating the pathogenicity of B. bassiana against D. fovealis, a pest that causes severe losses to farmers.     

The <Emphasis Type="Italic">Adh</Emphasis> locus and adaptation of <Emphasis Type="Italic">cn</Emphasis> and <Emphasis Type="Italic">vg</Emphasis> mutants in experimental populations of <Emphasis Type="Italic">Drosophila melanogaster MEIG</Emphasis>

A complex study on the adaptation of cn and vn mutants and the allozymes of alcoholdehydrogenase (ADH) was carried out in initially pure lines, and their panmixia populations during exchange of the mutant genotype with that of wild-type flies (C-S) and D) through saturating crossings. The relative adaptation of the genotypes was estimated by their effect on reproductive efficiency in the experimentally obtained population. Fecundity, lifespan, and the resistance of the studied genotypes to hyperthermia were investigated individually. It was shown that the high level of adaptation of the cn mutants and the low level of adaptation of the vg mutants was correlated with the presence of different ADH allozymes. In the studied population, the F-allozyme of ADH accompanied the vg mutation, while the S-allozyme of the enzyme was detected in cn mutants. Saturating crossings of C-S(Adh ^S)×vg(Adh ^F) and D(Adh ^F) × cn(Adh ^S), along with the parallel determination of the allele composition of the Adh locus, demonstrated that the complete substitution of the F-allozyme of ADH in the vg mutants by the S-allozyme in D flies, as well as the substitution of the S-allozyme of ADH in the cn mutants by the F-allozyme in D flies was realized only after the 15th–20th backcrosses. These results favor the coadaptation of cn and vg marker genes with alleles of the Adh locus and indicate the important role of the latter in the adaptation of genotypes. In the studied population, selection acted primarily against the vg mutants, which were inferior to the cn mutants, and heterozygote genotypes in indices of the main adaptation components.     

<Emphasis Type="Italic">Plectosphaerella cucumerina</Emphasis> as a bioherbicide for <Emphasis Type="Italic">Cirsium arvense</Emphasis>: proof of concept

Plectosphaerella cucumerina (Lindf.) W. Gams was evaluated as a bioherbicide for Cirsium arvense L. (Scop.) using a Canadian and a New Zealand isolate. Both isolates defoliated C. arvense when applied at 10¹³ conidia ha^?1 in water volumes ranging from 250 to 6400 l ha^?1 with a rapid decline in effect with declining conidial dose. Repeat application and the addition of the adjuvant Pulse^® penetrant to the conidial suspension increased the disease severity in C. arvense. Maximum disease occurred at 20 °C with a 48 h post-application dew period. The experiments demonstrate that P. cucumerina can defoliate C. arvense under the environmental conditions of temperate pastures where the weed is problematic. The results also show that modifications to formulation and strategic application may reduce the 48 h dew period requirement and risk to non-target species respectively, supporting the conclusion that the fungus has potential as a bioherbicide for C. arvense.     

<Emphasis Type="Italic">Aeromonas</Emphasis> and <Emphasis Type="Italic">Plesiomonas</Emphasis> species from scarlet ibis (<Emphasis Type="Italic">Eudocimus ruber</Emphasis>) and their environment: monitoring antimicrobial susceptibility and virulence

The present study aimed at evaluating the role of captive scarlet ibises (Eudocimus ruber) and their environment as reservoirs of Aeromonas spp. and Plesiomonas spp., and analyzing the in vitro antimicrobial susceptibility and virulence of the recovered bacterial isolates. Thus, non-lactose and weak-lactose fermenting, oxidase positive Gram-negative bacilli were recovered from cloacal samples (n = 30) of scarlet ibises kept in a conservational facility and from water samples (n = 30) from their environment. Then, the antimicrobial susceptibility, hemolytic activity and biofilm production of the recovered Aeromonas spp. and Plesiomonas shigelloides strains were assessed. In addition, the virulence-associated genes of Aeromonas spp. were detected. Ten Aeromonas veronii bv. sobria, 2 Aeromonas hydrophila complex and 10 P. shigelloides were recovered. Intermediate susceptibility to piperacillin-tazobactam and cefepime was observed in 2 Aeromonas spp. and 1 P. shigelloides, respectively, and resistance to gentamicin was observed in 4 P. shigelloides. The automated susceptibility analysis revealed resistance to piperacillin-tazobactam and meropenem among Aeromonas spp. and intermediate susceptibility to gentamicin among P. shigelloides. All Aeromonas isolates presented hemolytic activity, while 3 P. shigelloides were non-hemolytic. All Aeromonas spp. and 3/10 P. shigelloides were biofilm-producers, at 28 °C, while 10 Aeromonas spp. and 6/10 P. shigelloides produced biofilms, at 37 °C. The most prevalent virulence genes of Aeromonas spp. were asa1 and ascV. Scarlet ibises and their environment harbour potentially pathogenic bacteria, thus requiring monitoring and measures to prevent contamination of humans and other animals.