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.

Species of the genus Piper (Piperaceae) are of great importance for the cosmetics, pharmaceutical, insecticide and food industries because they accumulate compounds and metabolites (Fazolin et al. 2005;Silva et al. 2007;Ribeiro et al. 2015), stimulating scientific interest in several areas, such as genetic improvements, molecular biology, phytotechnics, and animal and plant health (Rodrigues et al. 2019).
Some species of mites belonging to the family Tetranychidae have been reported to be associated with plants of the genus Piper in Brazil, such as Tetranychus ludeni Zacher, 1913 on Piper spp. in São Paulo (Feres et al. 2005), Eotranychus tremae De Leon, 1957 on Piper spp. in São Paulo (Flechtmann 1981;Feres et al. 2005) and Tetranychus marianae McGregor, 1950 on Piper spp. in Pernambuco (Moraes & Flechtmann 1981).
In October 2020, a mite infestation was observed in Piper spp. kept in pots in a greenhouse that are part of the collection of Piperaceae belonging to Embrapa Amazônia Oriental (01°27'S; 48°30'W), in the municipality of Belém, state of Pará.
The abaxial and adaxial surfaces of the leaves and the collection of phytophagous and other mite specimens were observed with a stereomicroscope. The mites were preserved in 70% alcohol for subsequent assembly in Hoyer's medium. Identification was performed under a phase contrast optical microscope (Zeiss Imager Z2) and with the aid of a dichotomous key (Baker & Tuttle 1994).
The phytophagous mites were identified as Tetranychus marianae (female, male and immature mites), with tarsal I and duplex setae of tarsus I and males and tarsal I and II duplex setae of females, the main diagnostic characteristics of the species (Fig. 1). The specimens were deposited in the reference collection of the Museu de Ciências Naturais  The colonies of T. marianae were located preferentially on the abaxial surface of the leaves and, to a lesser extent, on the adaxial surface. The eggs were located preferentially close to the veins. Six species of Piper (P. hispidum, P. marginatum, P. montealegreanum, P. peltatum, P. reticulatum and P. tuberculatum) had colonies of T. marianae; however, only P. marginatum, P. peltatum and P. reticulatum had colonies on leaves that caused chlorosis and tanning to occur (Fig.  2).

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was identified as Amblyseius tamatavensis Blommers, 1974 and was collected from P. marginatum, P. reticulatum and Piper species without the presence of T. marianae (P. alatipetiolatum, P. arboreum, P. colubrinum, P. cernuum, P. divaricatum and P. nigrum). Tetranychus marianae was reported in approximately 105 host plants (Migeon & Dorkeld 2021). In Brazil, the only report of this species in a Piper sp. was the result of a collection obtained in September 1977 in the municipality of Recife, state of Pernambuco, without citing damage (Moraes & Flechtmann 1981;Flechtmann & Moraes 2017). In addition to this Piper sp., T. marianae was reported to be associated with Abelmoschus esculentus L. Moench (Malvaceae), Capsicum annuum L. (Solanaceae), Chenopodium ambrosioides L.  Regarding the predatorial Phytoseiidae, A. tamatavensis is widely distributed and has been reported as occurring in Africa, South and Central America, Asia and Oceania (Demite et al. 2021). In Brazil, it is widespread in all regions (Demite et al. 2021). In the Amazon biome, A. tamatavensis has been reported in the states of Amazonas (without indication of hosts; Vasconcelos & Silva 2015), Roraima (Citrus sp. (Rutaceae) and Cocos nucifera L. (Arecaceae) ;Gondim Jr. et al. 2012;Figueirêdo et al. 2019) and Pará (fruits and leaves of C. nucifera; Lawson-Balagbo et al. 2008). This species of Phytoseiidae seems to fit the Type III b group (generalist predators that live on glabrous leaves) defined by McMurtry et al. (2013). It was first reported in association with the red palm mite Raoiella indica Hirst, 1924 (Tenuipalpidae) in the state of Roraima (Gondim Jr. et al. 2012), and it has also been cited as a promising natural enemy of Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) (Cavalcante et al. 2017;Barbosa et al. 2019).
Despite the wide scientific importance of species of the genus Piper in Brazil and their use in breeding programs of species with significant economic importance (Rodrigues et al. 2019), the diversity of mites in these plants is practically unknown. In this study, phytophagous T. marianae was reported for the first time in the state of Pará in six species of Piper, while the predator A. tamatavensis is a new record in Piper spp. in Brazil.