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Scirtothrips dorsalis Hood is a pest of strawberry in Florida, causing foliar and fruit damage to young plants. A field-plot study was conducted in 2015–16 to compare the efficacy of flupyradifuron...

Scirtothrips dorsalis Hood is an invasive and foliar pest of Florida blueberry that reduces plant growth by feeding on new leaf growth. A sampling plan is needed to make informed control decisions for S. dorsalis in blueberry. Fourteen blueberry fields in central Florida were surveyed in 2017 and 2018 after summer pruning to determine the spatial and temporal distribution of S. dorsalis and to develop a fixed-precision sampling plan. A sampling unit of ten blueberry shoots (with four to five leaves each) was collected from one blueberry bush at each point along a 40 × 40 m grid. Field counts of S. dorsalis varied largely ranging from zero to 1122 adults and larvae per sampling unit. Scirtothrips dorsalis had aggregated distribution that was consistent within fields and temporally stable between summers, according to Taylor’s power law (TPL) (aggregation parameter, b = 1.57), probability distributions (56 out of 70 sampling occasions fit the negative binomial distribution), Lloyd’s index (b &gt, 1 in 94% occasions), and Spatial Analysis by Distance IndicEs (31% had significant clusters). The newly developed fixed-precision sampling plan required 167, 42, seven, or three sampling units to estimate a nominal mean density of 20 S. dorsalis per sampling unit with a precision of 5%, 10%, 25%, or 40%, respectively. New knowledge on S. dorsalis distribution will aid in evaluating the timing and effectiveness of control measures.

Scirtothrips dorsalis Hood infest strawberry (Fragaria x ananassa Duchesne, Rosaceae) fields from nearby crop fields and surrounding vegetation and cause injury to plants by feeding on young leaf tissues. Greenhouse and field studies were conducted to determine the short-range movement of S. dorsalis to assess the risk of an early S. dorsalis population to spread to adjacent plants. In a greenhouse, 25 potted strawberry plants were arranged in two concentric rows around a central plant, where plants in inner rows were 20 cm, and those in the outer rows were 40 cm from the central plant. In the field, 20 strawberry plants were arranged in two beds (90 cm apart), ten in each bed, and five plants in each row, with plants 30 cm apart. White sticky cards were placed at 60–120 cm from the central plant. Fifty S. dorsalis adults were released on a centrally located plant, and the numbers of S. dorsalis adults and larvae and feeding injury were recorded for 9–17 d on adjacent plants and sticky cards. Results showed that significantly more S. dorsalis adults and larvae remained on the initially infested plant compared to adjacent plants, although few adults were found up to 120 cm on sticky cards. The rate of spread of feeding injury was low with slight bronzing injury (

Seasonal abundance and spatial distribution of melonworm, Diaphania hyalinata L. (Lepidoptera: Crambidae), on yellow squash were studied during 4 crop-growing periods in 2014 in Homestead, Florida. The abundance of D. hyalinata larvae ranged from a minimum during Dec 2014 (1.3 ± 0.0 larvae per 2 leaves) when temperatures were relatively low (15–20 °C), to a maximum in Sep 2014 (6.6 ± 0.1 larvae per 2 leaves) when temperatures were relatively high (24–26 °C). The abundance of small larvae (L1 L2) was relatively greater, with a maximum of 7.1 ± 0.3 larvae per 2 leaves, as compared with medium-sized larvae (L3 L4) (2.4 ± 0.1 per 2 leaves) and large larvae (L5) (2.4 ± 0.1 larvae per 2 leaves) throughout the year. The abundance of large larvae was consistently low over the entire year. Diaphania hyalinata distributions tended to be aggregated (b > 1) during the crop-growing periods during May, Jun–Jul, and Sep 2014, when the population densities were relatively high, but were uniform (b < 1) during Dec 2014, when the population densities were low. A weak but statistically significant positive linear relationship existed between temperature and larval abundance. The results from this study will help squash and cucurbit growers of south Florida in monitoring melonworm infestations in the field and in developing a knowledge-based management program.

Echinothrips americanus Morgan is an important greenhouse foliage pest of vegetable and ornamental plants (Figure 1). This pest is polyphagous, reported from 48 plant families worldwide. The preferred hosts of Echinothrips americanus belong to the Araceae and Balsaminaceae plant families (CABI/EPPO 2014). This pest is native to eastern North America (Stannard 1968) and was first reported in 1984 on poinsettia, Euphorbia pulcherrima (Euphorbiaceae), in Georgia (Oetting 1987). Other important greenhouse crops damaged by this pest include Impatiens spp. (Balsaminaceae), gerbera, rose, sweet pepper, cucumber and eggplant (Vierbergen et al. 2006). On EDIS: https://edis.ifas.ufl.edu/in1246 On Featured Creatures: http://entnemdept.ufl.edu/creatures/ORN/THRIPS/Echinothrips_americanus.html

The melonworm, Diaphania hyalinata L. (Lepidoptera: Crambidae), is one of the most serious insect problems affecting cucurbit production. We evaluated the relative preference and suitability of yellow squash, zucchini, cucumber, and watermelon to melonworm by measuring its oviposition, larval feeding preference, survivorship, and developmental responses in the laboratory. Whole plants were used for oviposition study, whereas host leaf discs were used for all the other studies. Watermelon feeding resulted in the longest larval development period (14.3 d), greatest prepupal weights and survivals rates (92%; first instar to adult) among the four crops. However, for watermelon, adult oviposition preference (199.5 eggs/♀), egg survival (70%), and larval feeding (4.1% defoliation) were numerically or statistically lowest, and larval head capsule widths and whole-body lengths were smallest. When differences occurred among these variables, yellow squash, zucchini, and cucumber were each typically higher (or quicker to develop) than watermelon. So why do melonworm adults not prefer watermelon, or at least select it as frequently as squash and cucumber when ovipositing? The answer likely is that there might be some variation in the important chemical components among these cucurbits. We suggest that comparison of kairomones and allomones from watermelon and related cucurbits would be very useful for determining the combination resulting in the lowest risk of damage to the more susceptible cucurbits (assuming the levels can be modified without seriously affecting the crops).

Chilli thrips, (Scirtothrips dorsalis Hood; Thysanoptera: Thripidae), is an economically important pest of vegetable, fruit, and ornamental crops throughout Asia, Africa, Oceania, the Caribbean, and some parts of South America and is an invasive pest in several US states. Chilli thrips were first observed in Florida in 1991. It was first recorded in blueberries in Hernando, Pasco and Sumter counties in July of 2008. This 4-page fact sheet written by Oscar E. Liburd, Babu R. Panthi, and Douglas A. Phillips and published by the UF/IFAS Entomology and Nematology Department discusses the life cycle of the chilli thrips, plant damage it causes, and management recommendations for chilli thrips in blueberries in Florida.https://edis.ifas.ufl.edu/in1298

The false chinch bug, Nysius raphanus Howard, is a small, greyish, native North American herbivorous seed bug. It is recognized as the most serious pest among members of the genus Nysius, but reports of heavy infestations and serious crop damage are uncommon. Includes: Introduction - Distribution - Description and Life Cycle - Host Plants - Damage - Management - Selected Referenceshttps://edis.ifas.ufl.edu/in1212 Also published at http://entnemdept.ufl.edu/creatures/ORN/TURF/false_chinch_bug.html