Berries (i.e., blackberry, blueberry, raspberry, and strawberry) are popular fruits due to their pleasing flavor and year-round availability. Because berry consumption is also associated with health benefits (Foito et al. 2018, Huang et al. 2012, Yang and Kortesniemi 2015), the global market for berries has experienced significant growth (FAOSTAT 2023, González-Ramírez et al. 2020).

The worldwide demand for berries provides an enormous opportunity for food-producing countries such as Mexico, where the production of berries is mainly destined for exportation. Although a considerable capital investment is required, the high international prices have stimulated establishment of berry crops. In the last decade, cultivated land with berries has more than doubled in Mexico, from 24,000 to 55,000 ha (ANEBERRIES 2023). Mexico has become the world’s biggest producer of blackberries (298,024 tons), second in raspberry (128,848 tons), third in strawberry (861,337 tons), and the sixth in blueberries (48,999 tons) (FAOSTAT 2023, SIAP 2023). With an estimated US$4,700 million, berries are the second highest valuable agricultural product in Mexico, having a significant impact on the national economy (SENASICA 2023).

Grower preference for profitable cash crop production has altered land use in many regions of Mexico. Traditional crops, such as maize, sorghum, soybean, sugarcane, and wheat, have been gradually replaced in favor of products for the international markets, such as berries (González-Ramírez et al. 2020, Orozco-Ramírez et al. 2017). Establishment of berry crops, however, usually has resulted in new insect–plant associations and the introduction of invasive pests into the new berry-growing areas (Rodriguez-Saona et al. 2019). For example, the spotted-wing drosophila, Drosophila suzukii (Matsumura), one of the main pests of berries, was detected in Michoacán state in 2011 (Castro-Sosa et al. 2017). More recently, the invasive pest known as “chilli thrips,” Scirtothrips dorsalis Hood, was also reported from Michoacán on blueberries (Ortiz et al. 2020).

Thrips are particularly attracted to berry crops. Several dozen species have been reported feeding on flowers, fruits, or leaves of berries without inflicting serious injuries to plants. Some of the more prominent pest species of thrips reported from different parts of the world are Frankliniella bispinosa (Morgan), Frankliniella fusca (Hinds), Frankliniella hawaiiensis (Morgan), Frankliniella intonsa (Trybom), Frankliniella occidentalis (Pergande), Frankliniella schultzei Trybom, Frankliniella tritici (Fitch), Thrips fuscipennis Haliday, Thrips imaginis Bagnall, Thrips major Uzel, Thrips tabaci Lindeman, Scirtothrips citri (Moulton), and Scirtothrips dorsalis (Arévalo and Liburd 2007, Haviland et al. 2016, Nielsen et al. 2021, Renkema et al. 2020, Rodriguez-Saona et al. 2010, Steiner and Goodwin 2005). Most of these species can feed and reproduce on all stages of growth of the host plants as well as on all parts of developing flowers and young leaves. Damage by thrips results in necrotic lesions, distortion of fruits, and flower and fruitlet abortion (Rhodes and Liburd 2017, Steiner and Goodwin 2005). Besides the direct damage caused by thrips, they have been implicated as potential vectors of berry viruses (Tan et al. 2022). Although it is well known that berries are infected by multiple viruses (Martin et al. 2013, Martin and Tzanetakis 2015), the only record of an orthotospovirus transmitted by thrips to berry crops is the impatient necrotic spot virus, reported in blackberry (Tzanetakis et al. 2009). There are other cases involving pollen-transmitted viruses (Ilarvirus) in berries, where thrips are acting as vectors by moving pollen from infected to noninfected plants (Dara 2015, Martin et al. 2013, Martin and Tzanetakis 2015).

Considering the importance of thrips in berry production, in this study we surveyed and identified the thysanopteran fauna associated with blackberry, blueberry, raspberry, and strawberry crops in commercial orchards of Mexico. Our objective was to produce an inventory of thrips species present in these crops and identify the dominant species. We believe this information could eventually be useful in other studies to develop crop protection strategies against damaging thrips species.

Materials and Methods

We sampled for thrips on berry crops at 41 commercial plantations of blackberry, blueberry, raspberry, and strawberry located in Guanajuato, Jalisco, Michoacán, and Sinaloa during spring and summer 2020. Because of differences in berry phenology during the study, the number of samples was not equal across the crop species or locations (Table 1). At each locale, the sample area consisted of approximately 0.5 ha. Plants were not sprayed with insecticide at least 1 wk before sampling. Thrips samples were carefully taken from plants for about 30 min, following a zigzag path to cover the whole sampling area. Plants were shaken over a plastic tray (30 × 50 cm) moistened with alcohol, to detach the thrips from plants. Thrips dropped onto the tray were handled with a camel-hair brush and placed in vials containing 70% ethanol.

Table 1 Location of commercial berry orchards for thrips survey.

View Fullscreen

In the laboratory, samples in ethanol were processed. Thrips were counted and separated by morphotypes by using a stereo microscope. A subsample based on the different morphotypes was taken from vials for identification purposes. After being punctured in the abdomen with a fine needle to remove the internal body content, thrips were mounted on slides using Hoyer’s mounting medium. Slides were dried in an oven at 45°C for 1 wk and eventually identified to species level following the taxonomic keys in Mound and Marullo (1996), Hoddle et al. (2012), and Cavalleri and Mound (2012), among others. Taxonomic determinations of thrips were made by the first and second authors. Representative identified specimens were deposited in the personal collection of F.I. and are available upon request.

Results

Samples from the four berry crops yielded 19 species of thrips representing 11 genera (Table 2). Frankliniella, Neohydatothrips, and Scirtothrips were the predominant genera with six, three, and two species, respectively. Of the 19 species collected, 17 were phytophagous, 1 species (Hoplandrothrips affinis Hood) was fungivorous, and 1 species, Scolothrips sexmaculatus (Pergrande), was predatory, feeding on other thrips and mites.

Table 2Diversity of thysanopterans in commercial berry crops of Mexico. Species were identified from subsamples taken, considering the different morphotypes in the original sample.*

View Fullscreen

Blueberry harbored the greatest number of thrips species, with 11 collected, followed by raspberry, strawberry, and blackberry, with 9, 9, and 7 species, respectively. Only three species of thrips occurred on all four berry crops: F. occidentalis, Neohydatothrips burungae (Hood), and Scirtothrips dorsalis Hood. Two thrips species that are widely reported in Mexico, Frankliniella cephalica (Crawford) and Frankliniella gossypiana Hood, were not detected in strawberry but were common in the other three berry crops (Table 2).

In total, 4,394 thrips were collected in these surveys, with 3,795 being adults and 599 larvae. Of those 4,394 specimens, 53.7% were collected from blackberry and 16.1, 15.5, and 14.8% were from blueberry, strawberry, and raspberry, respectively (Table 3; Fig. 1). Frankliniella occidentalis was by far the predominant species collected at all 41 plantations and in the four berry crops. More than 50% of thrips adults collected from the four berry crops were F. occidentalis. The second most predominant species was S. dorsalis, especially in blueberry, blackberry, and strawberry. Frankliniella cephalica and F. gossypiana were frequently collected and should also be considered a potential risk for the berry production in Mexico.

Table 3Numbers of thrips adults and immatures collected in sampling of commercial berry crops in Mexico.

View Fullscreen

View Figure

• Download as Powerpoint
• Download Figure

Discussion

Our survey successfully assessed the thrips species inhabiting commercially grown blackberry, blueberry, raspberry, and strawberry in Mexico. The sampling was conducted at 41 localities within the primary area cultivated with berries so that the study was representative and provided important information on the thrips species composition associated with berry crops.

Of the 19 thrips species identified in the samples from these berry crops, 17 are phytophagous. The predominant species in the four berry crops was consistently F. occidentalis. Its relative abundance with respect other species of thrips was 52.9% in blueberry, 69% in raspberry, 79.6% in blackberry, and 88.7% in strawberry. The second most abundant species was S. dorsalis, varying from 2.6% in strawberry to 24.6% in blueberry. The third and fourth most common species found were F. cephalica and F. gossypiana, two species of thrips that are very common in tropical regions of Central America (Mound and Marullo 1996). These two species were more frequently collected in samples from Sinaloa (Table 2). Other prominent species captured included F. borinquen, N. burungae, and T. tabaci. Apparently, only F. occidentalis and S. dorsalis appear to be persistent pests of economic importance in berries, whereas the other species are considered as occasional pest species. Although most thrips species are herbivorous, there currently is a low risk of economic damage to berry crops by these other species due to their low population numbers.

Frankliniella occidentalis and S. dorsalis are two of the most common thrips damaging berry crops. Both species are invasive, highly polyphagous, and widespread globally (Atakan 2011, Kumar et al. 2013, Pinent et al. 2011, Reitz et al. 2020, Renkema et al. 2020). They can establish in new habitats relatively easily and are highly adaptable to different hosts. Other than berries, approximately 240 and 225 plant species are reported as hosts for F. occidentalis (Sampson 2018, Tommasini and Maini 1995) and S. dorsalis (Kumar et al. 2013), respectively. Usually, adults and larvae of F. occidentalis feed on leaves, flowers, and developing fruits (Reitz 2009), whereas S. dorsalis feeds primarily on fresh leaves and young fruits (Renkema et al. 2020). Given the pest status and risk of these two thrips species and their distribution throughout the main berry-growing areas of Mexico, we recommend that implementing a thorough monitoring program for thrips populations should be instituted to prevent damage and crop losses from these pests.

Our results concur with those of other published thrips surveys reported from Mexico. Six of the species found in our survey have already been reported from berry crops in Mexico. For example, F. occidentalis was reported from numerous localities infesting blackberry, blueberry, and raspberry (Cubillos-Salamanca et al. 2019, Martínez-Ortega et al. 2023, Ortiz et al. 2020, Sánchez-Roncancio et al. 2001). The corn trips, Frankliniella williamsi Hood, was recorded from blackberry and raspberry (Mejía-Mandujano et al. 2023, Sánchez-Roncancio et al. 2001), F. gossypiana has been reported in blueberry (Mejía-Mandujano et al. 2023), F. cephalica from blueberry (Ortiz et al. 2020), S. dorsalis from blackberry and blueberry (Martínez-Ortega et al. 2023, Ortiz et al. 2020), and T. frici from blackberry (Cubillos-Salamanca et al. 2019). The remaining 13 species that we collected and identified represent new records for berry crops in Mexico.

Cubillos-Salamanca et al. (2019) also confirmed that F. occidentalis was the most common species in samples collected from blackberry in Jalisco and Michoacan. Zamora-Landa et al. (2020) collected and identified only three species of thrips from blackberry and blueberry crops in Michoacan: Thrips palmi Karny, Frankliniella bruneri Watson, and Frankliniella fortissima Watson. Among those, the dominant species was T. palmi, constituting 76.7% of those thrips collected. Ortiz et al. (2020) found S. dorsalis as the most abundant species on blueberry leaves collected in Michoacan, with F. occidentalis being the second most predominant. Bayardo-Cambero et al. (2023) reported that, in Nayarit, they found eight phytophagous species associated with blueberry, with S. dorsalis by far the most predominant species. Mejía-Mandujano et al. (2023) noted that S. dorsalis was the most economically important thrips species in organic blueberries growing in Jalisco. Finally, in a study carried out in Michoacan on blackberry and blueberry, Martínez-Ortega et al. (2023) reported that 96% of species collected belonged to Frankliniella and Scirtothrips. The most abundant species in blackberry var. Laurita and Elvira was F. occidentalis, whereas S. dorsalis was dominant in blackberry var. Dasha and blueberry var. Arana. Although all these studies were performed in diverse places and by using different methodologies for the collection of thrips, their conclusions align with the results that we obtained in our study.

In summary, our study provides baseline data on the diversity of thysanopterans occupying berry crops in Mexico. The survey confirms the presence of 19 thrips species in 41 berry-growing locales, with F. occidentalis and S. dorsalis being the predominant species, followed by F. cephalica and F. gossypiana. With the knowledge that these four species are invasive, polyphagous, and widespread, severe economic damages in berry crops are expected in orchards where control measures are not applied in a timely manner. We hope that the data gathered in this survey, complemented by results provided by other related studies carried out in Mexico, will be used as a basis for further research dealing with monitoring of thrips and development of insect pest management plans.