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The two-spotted spider mite, Tetranychus urticae Koch, is one of the main strawberry pests in Brazil and many other countries. The objective of this study was to compare the resistance of eight strawberry genotypes ('Albion', 'IAC Guarani', 'IAC Princesa Isabel', 'Oso Grande', IAC T-0104, IAC 12, IAC 4 and IAC 1.13) to the two-spotted spider mite, by assessing injury level, biological parameters and host preference of the mite. To facilitate the interpretation of the results, leaf trichomes of each genotype were quantified. Thirty days after the artificial infestation of the genotypes with the mite, IAC T-0104, IAC 12 and 'IAC Princesa Isabel' showed the lowest injury levels. 'IAC Princesa Isabel', IAC 4 and IAC T-0104 were distinguished from other genotypes by the highest mean generation time (T) of the mite, while 'IAC Guarani' was distinguished by the lowest T value. Significantly lower values of intrinsic rate of increase (r m ), finite rate of increase (λ) and net reproductive rate (R o ) were determined on 'IAC Princesa Isabel' and IAC 1.13. The mite showed preference for 'IAC Guarani', as inferred by the larger number of females when offered the chance to select the detached host leaflets. Trichome density was highest on IAC 1.13 and lowest on IAC T-0104, IAC 12, 'Albion' and 'Oso Grande'. The results suggested that 'IAC Princesa Isabel', IAC T-0104 and IAC 12 are resistant, IAC 4 and IAC 1.13 are moderately resistant, and 'IAC Guarani', 'Oso Grande' and 'Albion' are susceptible to the mite.

In Norway, strawberry producers use cereal straw mulching to prevent berries from contacting the soil and to control weeds. We hypothesized that organic matter such as straw mulch also favors the maintenance of predatory mites which visit strawberry plants at nighttime. We compared mite diversity in cereal straw exposed for different periods in strawberry fields and evaluated their possible migration to plants in two experiments with potted plants in 2019. An ‘Early season’ experiment compared no mulching (T1), oat straw mulch exposed in field since 2018 (T2), or 2017 (T3), while a ‘Mid-season’ experiment compared no mulching (T1), barley straw mulch from 2018 (T2), or a mix from 2017 and 2018 (T3). To provide edaphic predatory mites with a potential source of food, all plants were infested with two-spotted spider mite (Tetranychus urticae Koch). Results suggested that straw mulch facilitates the prevalence of predatory mites in strawberry fields. Most predatory mite visits were at night, confirming our initial hypothesis. Predominant nocturnal mites on leaves belonged to Melicharidae (Proctolaelaps sp.) (‘Early season’, T2), Blattisociidae (Lasioseius sp.) (‘Early and Mid-season’, T3) and Phytoseiidae (‘Mid-season’, T2). Parasitus consanguineus Oudemans & Voigts was the predominant species (‘Early season’, T3) at the base of plants. Anystidae were diurnal visitors only (‘Mid-season’, T2). Future studies should evaluate the predation potential of Proctolaelaps sp. and Lasioseius sp. on two-spotted spider mite and other strawberry pests.

The sugarcane weevil, Sphenophorus levis Vaurie, 1978 (Coleoptera: Curculionidae), is a pest of sugarcane in Brazil. Lasioseius prorsoperitrematus Abo-Shnaf, Sánchez & Moraes, 2016 (Acari: Blattisociidae), described from the Dominican Republic, is reported from Brazil in association with S. levis in Iracemápolis, São Paulo state. The actual role of each organism in this association needs to be verified. A key to species of Lasioseius Berlese, 1916 recorded from Brazil associated to Coleoptera is provided.

Integrade pest management in culture of strawberry in southern of Minas Gerais The southern of Minas Gerais is the main region producing strawberries (Fragaria x ananassa Duch.) in Brazil. The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is considered one of the main strawberry pests in Brazil and in several countries. An important practice in strawberry cultivation refers to soil cover, which is usually made with polyethylene film, but it is expensive and generates very persistent residues in the environment. The objective of this study was to compare the resistance of eight strawberry genotypes ('Albion', 'IAC Guarani', 'IAC Princesa Isabel', 'Oso Grande', IAC T-0104, IAC 12, IAC 4 and IAC 1.13); to determine the effect of soil cover (with dehydrated coffee pulp, known as coffee straw) on the pests mites/ pathogens and predatory mites of this crop; to compare the occurrence of pests, pathogens and natural enemies between an organic and a conventional strawberry crop. The results indicated that 'IAC Princesa Isabel', IAC T-0104 and IAC 12 are resistant, IAC 4 and IAC 1.13 are moderately resistant, and 'IAC Guarani', 'Oso Grande' and 'Albion' are susceptible to the two-spotted spider mite. 'Oso Grande' and 'Albion' are widely used by producers in the southern of Minas Gerais. The use of coffee straw increased the number of edaphic predators, both in the soil beds (field) and in pots (laboratory) as well as in strawberry leaflets. The Gamasina Proctolaelaps pygmaeus (Müller) (Melicharidae) was seen on strawberry leaftlets, mainly in the nocturnal period. Higher numbers of the two-spotted spider mites and disease severity were observed in plants grown on soil covered with polyethylene. In addition, the level of the two-spotted spider mite infected by the fungi Neozygites floridana (Weiser and Muma) was higher in plants cultivated in soil covered with coffee straw. No significant difference was observed between yield in soil covered with polyethylene and in soil covered with dry coffee straw. The results of the comparison of the occurrence of arthropods and pathogens between the organic and conventional systems showed fewer occurrences of the two-spotted spider mites and predators in conventional strawberry cultivation, but considerable occurrence of thrips, whitefly and gray mold. The incidence of dendrophoma and leaf spots caused by pestalotia was the same in both cropping systems. The results suggest the convenience to continue the development process of the genotypes that were less affected by the two-spotted spider mite, which could be used in the future by producers, and the conduction of complementary studies to evaluate the performance of crops in organic system that incorporate the use of coffee straw as soil coverage.