Tetranychus marianae McGregor, 1950 (Acari: Tetranychidae) in Piper (Piperaceae) species in the state of Pará, Brazil

This study reports the occurrence of the phytophagous mite Tetranychus marianae McGregor, 1950 (Tetranychidae), in species of the genus Piper (P. hispidum Sw., P. marginatum Jacq., P. montealegreanum Yunk., P. peltatum L., P. reticulatum L., and P. tuberculatum Jacq.) (Piperaceae) and the predator mite Amblyseius tamatavensis Blommers, 1974 (Phytoseiidae), in species and cultivars of Piper nigrum L., from the Piperaceae collection of Embrapa Amazônia Oriental in Belém, Pará.

Bioactivity of essential oils for the management of Tetranychus urticae Koch and selectivity on its natural enemy Neoseiulus californicus (McGregor): A promising combination for agroecological systems

The two-spotted spider mite, Tetranychus urticae, causes damage to crops grown in northeast Brazil. The adoption of biological control methods and curative methods (plant-based insecticides) is an essential practice for pest management in agroecological systems. Therefore, the aim of the present study was to investigate the chemical properties, toxicity, and ovicidal activity of essential oils (EOs) from Lippia sidoides, Croton rhamnifolioides, Croton grewioides, Citrus sinensis, Citrus limon, Citrus aurantiifolia and Piper divaricatum for the control of T. urticae and determine the selectivity of these EOs regarding the predator mite Neoseiulus californicus. The chemical analysis (gas chromatography–mass spectrometry) of the EOs enabled the identification of 98 compounds. The major constituents were carvacrol (L. sidoides), β-caryophyllene (C. rhamnifolioides), (E)-anethole (C. grewioides), limonene (Citrus spp.), safrole and methyl eugenol (P. divaricatum). All oils exhibited satisfactory toxicity to the eggs and females of T. urticae and were even more toxic than the commercial product Azamax. The L. sidoides oil exhibited greater toxicity compared to the other oils, with LC50 values of 0.05 and 0.09 µL mL-1 for females and eggs, respectively. All oils tested were selective to N. californicus, with RS values ranging from 3.61 to 23.28 for C. aurantiifolia and C. grewioides, respectively. Therefore, the use of products based on the EOs studied in combination with the natural enemy N. californicus is a viable option in agroecological systems for the management of T. urticae.

Dispersal of entomopathogenic fungi, Metarhizium anisopliae and its synergistic with predatory mite, Phytoseiulus macropilis for controlling Tetranychus urticae

The entomopathogenic fungus “Metarhizium anisopliaeˮ and predatory mite “Phytoseiulus macropilisˮ are effective biological controlling agents of Tetranychus urticae. Recent studies have shown that predatory mites, used as biocontrol agents can be loaded with entomopathogenic fungal conidia to increase infection rates in pest populations. It was necessary to study the effect of M. anisopliae against P. macropilis before executing the experiment. The results showed that the predator mite was more effected by 1×109 conidia/ml of M. anisopliae, while the predator had low effect with 1×106 conidia/ml of M. anisopliae. It was found that the predator had poor effect at indirect spray. Results showed that dispersal of M. anisopliae loaded on P. macropilis delivered high numbers of conidia to T. urticae infested leaves, thereby increased the proportion of T. urticae that came into contact with the fungus.Our study suggests that loading certain predatory mite species with fungal conidia can increase their capacity to suppress thrips populations by combining predation and dispersing pathogens when releasing the loading predatory mite with M. anisopliae for controlling T. urticae on cucumber crop under greenhouse conditions

The impact of pesticides used in greenhouses, on the predatory mite neoseiulus californicus (parasitiformes, phytoseiidae)

Nine commercial pesticides currently used in Russian greenhouses against pests (aphids, thrips, whiteflies) were selected to determine their toxicity to predatory mite Neoseiulus californicus McGregor in order to find out the potential use him affected by chemical treatments Vertimec (abamectin), Fitoverm (aversectin C), Clipper (bifenthrin), Novaction (malation), Oberon (spiromesifen), Bitoxibacillin (Bacillus thuringiensis var. thuringiensis), Actara (tiametoxam), Admiral (piriproxifen), Confidor (imidacloprid), Mospilan (acetamiprid). The recommended concentration of the preparation (T), half the concentration (1/2T), and a double concentration (2T) were used on the female mite in the experiments. The side effects of the pesticides applied to the predator mite were determined one, three, and five days after the application. The recommended concentration of the preparation of Vertimec, Fitoverm and Clipper showed a higher toxic effect on N. californicus femails (mortality rate 100%). The obtained data reveals the impossibility of their joint application with the release of N. californicus. The toxic effects of Mospilan, Confidor, Admiral, Actara, Bitoxibacillin and Novaktion on N. californicus females were a low level (mortality of females 0-16,6%). The present study confirms that the use of predatory mite N. californicus in combination with these pesticides prospectively in Integrated Pest Management in Russian greenhouse conditions.

Sublethal effect of Abamectin in the functional response of the predator Phytoseiulus persimilis (Athias-Henriot) on Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae)

The biological control used for the control of Tetranychus urticae (Koch) is the predator mite Phytoseiulus persimilis (Athias-Henriot). It is important to the know the effects of acaricides on the biological behavior the Abamectin on the functional response of P. persimilis. The functional response of the predator was of type II exposed to concentration of Abamectin, the functional response parameters: successful attack rate (a’), handling time (Th), search efficiency and the maximum predation theory (T/Th) were affected by the acaricide. The predator spends more time in persecute, dominate, consume and prepair it self to the next searching comparing with the proof subject an the predation ability was affected.

Lethal time of insecticides on the predator mite Neoseiulus fallacis (Acari: Phytoseiidae) following topical exposure

Neoseiulus fallacis (Garman) (Acari: Phytoseiidae) is an efficient predator of the European red mite (ERM) (Panonychus ulmi (Koch); Acari: Tetranychidae) in Michigan, United States of America apple orchards and an important part of integrated pest management. Four reduced-risk insecticides (acetamiprid, spinetoram, chlorantraniliprole, and novaluron) and two conventional insecticides (esfenvalerate and carbaryl) were tested against N. fallacis for topical toxicity effects. Bioassays using a Potter spray tower were conducted to measure the topical toxicity of compounds when applied at field rate concentrations to N. fallacis. Lethal time was measured for adult N. fallacis at 4, 24, 48, 72, and 96 hours after treatment. Carbaryl and esfenvalerate showed the highest levels of toxicity to adult N. fallacis with shortest lethal time values (LT50) whereas the reduced risk insecticides novaluron, acetamiprid, spinetoram, and chlorantraniliprole were nontoxic. This study provides important information to apple growers regarding direct lethal effect of insecticides on predator mites and its implications to integrated mite management.

Role of Predatory Mites in Persistent Nonoccupational Allergic Rhinitis

Mites can sensitize and induce atopic disease in predisposed individuals and are an important deteriorating factor in patients with allergic rhinitis, asthma, and atopic dermatitis. Although Pyroglyphidae mites have been extensively studied, very scarce reports are available on Cheyletidae spp. especially regarding human respiratory pathology. The main objective of the present study is to investigate the clinical role of this predator mite (Cheyletus eruditus) as a respiratory antigen in a selected sensitized human population. Fifty-two adult patients were recruited from the outpatient allergy clinic to assess their eligibility for the study. The thirty-seven subjects with persistent allergic rhinitis (PAR) who fulfilled the ARIA criteria had a positive IgE response confirmed by skin prick test (SPT) toC. eruditus. Only those individuals (37/47) with a positive SPT toC. eruditusshowed a positive nasal provocation test (NPT), while 10 patients with nonallergic mild-to-moderate persistent rhinitis,control group, had a negative NPT withC. eruditus. The present paper describes a new role for the predator miteCheyletus eruditusas a respiratory allergen in a selected subset of patients in a subtropical environment afflicted with persistent nonoccupational allergic rhinitis.