Effects of Growing Media Containing Diatomaceous Earth on the Fungus Gnat Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae)

Fungus gnats (Bradysia spp.) are major insect pests in greenhouses. The adult stage is primarily a nuisance whereas the larval stage is directly responsible for plant injury by feeding on plant roots or tunneling into stems. Insecticides are used to deal with fungus gnat larvae in growing medium, although sometimes with limited success. This study evaluated the potential of using a soil amendment—diatomaceous earth (DE) incorporated into growing media—for controlling the fungus gnat Bradysia sp. nr. coprophila. Two experiments were conducted by testing a series of growing media containing various concentrations of diatomaceous earth, and several without diatomaceous earth. The effects of the growing media containing diatomaceous earth on both the 2nd and 3rd instars of fungus gnat larvae were determined by recording the number of adults captured on yellow sticky cards (2.5 × 2.5 cm). Based on the results obtained from both experiments, the addition of DE to growing medium, at the concentrations tested, did not negatively affect or increase efficacy against both the 2nd and 3rd instars. This suggests that incorporating DE into commercially available growing medium may not be beneficial to greenhouse producers. However, further research is needed to assess whether differential larval susceptibility and moisture content influence the ability of DE to control soil-dwelling arthropods.

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Effects of Growing Medium Type and Moisture Level on Predation by Adult Rove Beetle, Dalotia coriaria (Coleoptera: Staphylinidae), on Fungus Gnat, Bradysia sp. nr. coprophila (Diptera: Sciaridae), Larvae under Laboratory and Greenhouse Conditions

HortScience ◽

10.21273/hortsci11842-17 ◽

2017 ◽

Vol 52 (5) ◽

pp. 736-741 ◽

Cited By ~ 2

Author(s):

Nathan J. Herrick ◽

Raymond A. Cloyd

Keyword(s):

Moisture Content ◽

Laboratory Experiment ◽

Growing Media ◽

Rove Beetles ◽

Rove Beetle ◽

Fungus Gnats ◽

Growing Medium ◽

Significant Difference ◽

Fungus Gnat ◽

Saturated Treatment

The fungus gnat, Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae), is an insect pest of greenhouse production systems. The rove beetle, Dalotia coriaria [Kraatz] (Coleoptera: Staphylinidae), is a commercially available predator of certain greenhouse insect pests that reside in growing media, including fungus gnats. There is minimal information discussing how growing medium type and moisture level (watering treatment) impact the interactions between pests and natural enemies. Therefore, we conducted laboratory and greenhouse experiments to investigate the influence of two growing media (Sunshine® LC1 Professional Growing Mix and Fafard® 3B Mix Professional Formula) and two moisture levels (“constantly saturated” and “initially saturated”) on predation by adult D. coriaria on B. sp. nr. coprophila larvae after releasing one or two rove beetle adults. In the laboratory experiment, moisture content or the amount of water retained by the growing medium did not significantly influence the recovery of adult fungus gnats for any of the rove beetle treatments. However, there was a significant difference in the recovery of fungus gnat adults between the two growing media. Fewer fungus gnat adults emerged from the Sunshine® LC1 Professional Growing Mix (0.9 ± 0.2 adults) than the Fafard® 3B Mix Professional Formula (6.0 ± 0.9 adults). Significantly fewer adult fungus gnats were recovered in the treatments where one rove beetle adult was released (2.7 ± 0.7 adults) and two rove beetle adults were released (2.3 ± 0.5 adults) compared with the control without rove beetles (5.4 ± 1.4 adults). However, there was no significant difference between the number of rove beetle adults released. In contrast to the laboratory experiment, moisture content in the greenhouse experiment significantly influenced the recovery of adult fungus gnats. More adult fungus gnats were recovered from the “constantly saturated” treatment (9.9 ± 1.4 adults) than the “initially saturated” treatment (3.8 ± 1.0 adults). Similar to the laboratory experiment, there was a significant difference in the recovery of fungus gnat adults between the two growing media, with fewer adults captured from the Sunshine® LC1 Professional Growing Mix (3.2 ± 0.8 adults) than the Fafard® 3B Mix Professional Formula (10.4 ± 1.4 adults). However, the treatments with rove beetle adults [one rove beetle (6.6 ± 1.8 adults) or two rove beetles (5.3 ± 1.5 adults)] were not significantly different from the control without rove beetles (8.6 ± 1.5 adults), suggesting that the growing media and moisture levels were acting directly on fungus gnat survival. The results of our study demonstrate that survival of fungus gnat larvae that reside in the growing medium and the success of rove beetle adults used to regulate these pests can be influenced by growing media and the moisture content within growing media.

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Effect of Plant-growing Media on Western Flower Thrips, Frankliniella occidentalis, Pupae and Fungus Gnat, Bradysia sp. nr. coprophila, Larvae under Laboratory Conditions

HortScience ◽

10.21273/hortsci15139-20 ◽

2020 ◽

Vol 55 (8) ◽

pp. 1323-1326

Author(s):

Nathan J. Herrick ◽

Raymond A. Cloyd

Keyword(s):

Frankliniella Occidentalis ◽

Insect Pests ◽

Arbuscular Mycorrhizal Fungus ◽

Larval Mortality ◽

Mycorrhizal Fungus ◽

Western Flower Thrips ◽

Arbuscular Mycorrhizal ◽

Growing Media ◽

Flower Thrips ◽

Fungus Gnat

Western flower thrips, Frankliniella occidentalis, and fungus gnats (Bradysia spp.) are major insect pests of greenhouse production systems. Both insect pests have life stages that reside in the soil or plant-growing medium: prepupae and pupae of western flower thrips and fungus gnat larvae. There are unsubstantiated allegations made by a manufacturer that certain plant-growing media that contain a bacterium, Bacillus pumilus, and arbuscular mycorrhizal fungus, Glomus intraradices, negatively affect the survival of western flower thrips pupae and fungus gnat larvae. Therefore, we conducted a study involving laboratory experiments replicated over time (2019 and 2020) to investigate the influence of the plant-growing media Pro-Mix BX + Mycorrhizae and Pro-Mix BX + Biofungicide + Mycorrhizae on western flower thrips pupae and fungus gnat larvae. All experiments involved placing western flower thrips pupae or fungus gnat larvae (second and third instar) into 473-mL deli containers with the different treatments (plant-growing media). A 5 × 4-cm section of a yellow sticky card was affixed to the lid of each deli container. After 21 days, the number of western flower thrips or fungus gnat adults that emerged from the growing media and were captured on the yellow sticky cards was recorded. The use of the yellow sticky card was an indirect assessment of western flower thrips pupal or fungus gnat larval mortality. We found none of the plant-growing media tested that contained a bacterium and/or arbuscular mycorrhizal fungus affected the survival of western flower thrips pupae or fungus gnat larvae. Therefore, greenhouse producers should be leery of information provided by manufacturers that does not contain valid, scientifically based data.

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Procedure to Enhance the Recovery Rate of Fungus Gnat, Bradysia sp. nr. coprophila Lintner (Diptera: Sciaridae) Adults from Growing Medium

HortScience ◽

10.21273/hortsci.43.5.1528 ◽

2008 ◽

Vol 43 (5) ◽

pp. 1528-1530 ◽

Cited By ~ 2

Author(s):

Raymond A. Cloyd ◽

Amy Dickinson

Keyword(s):

Biological Control ◽

Moisture Content ◽

Biological Control Agents ◽

Management Options ◽

Initial Water ◽

Data Set ◽

Fungus Gnats ◽

Growing Medium ◽

Fungus Gnat ◽

Water Volumes

Fungus gnats, Bradysia spp., are major insect pests in greenhouses and interiorscapes. Management typically involves the use of either insecticides or biological control agents such as entomopathogenic nematodes. Efficacy trials provide information to greenhouse producers on the effectiveness of these management options. However, a simple procedure that rapidly evaluates the performance of control products against fungus gnat larvae is needed. Because fungus gnat larvae inhabit the growing medium, excess or deficient growing medium moisture may reduce adult fungus gnat emergence, thus confounding effects from efficacy trial treatments. Therefore, it is important to determine the amount of moisture and moisture content that results in the highest recovery of fungus gnat adults. We conducted two replicated experiments in a completely randomized design using a range of initial water volumes (treatments) and two larval stages (second and third) of the fungus gnat, Bradysia sp. nr. coprophila. The success of the procedure was based on the number of fungus gnat adults that emerged per treatment. In the first experiment, initial water volumes of 0, 25, 50, 75, 100, 150, and 200 mL were applied to 300 mL of a soilless growing medium consisting of 50% composted pine bark, 20% Canadian sphagnum peatmoss, 10% perlite, and 20% medium coarse vermiculite (SB300 Universal Mix). In general, the highest mean numbers (range, 11.2 to 14.6) of fungus gnat adults were recovered from growing medium treated with 50, 75, and 100 mL of water. In the second experiment, initial water volumes (treatments) of 50, 55, 60, 65, 70, and 75 mL were applied to 300 mL of the soilless growing medium (SB300 Universal Mix). There were no significant differences in the mean number of fungus gnat adults recovered regardless of the larval instar (second instar: 15.8 to 17.7; third instar: 14.4 to 17.4). The final percent moisture content ranged from 65% to 68% for the second instars and 56% to 66% for third instars. This study demonstrates that the highest number of fungus gnat adults may be recovered from soilless growing medium (SB300 Universal Mix) treated with between 50 and 75 mL of water, thus enhancing the confidence in any data set generated when evaluating insecticides or biological control agents for control of fungus gnats.

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Effects of Growing Medium Type and Predator:Prey Ratio on Rove Beetle, Dalotia coriaria (Coleoptera: Staphylinidae), Adult Predation on Fungus Gnat, Bradysia sp. nr. coprophila (Diptera: Sciaridae), Larvae

HortScience ◽

10.21273/hortsci13268-18 ◽

2018 ◽

Vol 53 (10) ◽

pp. 1441-1446 ◽

Cited By ~ 2

Author(s):

Nathan J. Herrick ◽

Raymond A. Cloyd

Keyword(s):

Production Systems ◽

Insect Pests ◽

Insect Pest ◽

Greenhouse Production ◽

Rove Beetles ◽

Greenhouse Experiments ◽

Rove Beetle ◽

Growing Medium ◽

Fungus Gnat ◽

Medium Type

Fungus gnats, Bradysia spp. (Diptera: Sciaridae), are major insect pests because the larvae can directly damage plants grown in greenhouse production systems. In general, insecticides are commonly used to suppress fungus gnat larval populations. However, the rove beetle, Dalotia coriaria (Kraatz) (Coleoptera: Staphylinidae), a commercially available predator of insect pests, including fungus gnat larvae, may be an alternative to using insecticides. Growing medium selection used for growing plants can influence insect pest and predator interactions in greenhouse production systems; however, quantitative information is limited. Therefore, we conducted greenhouse experiments and a laboratory experiment to determine the effects of growing medium type on D. coriaria adult predation and fungus gnat, Bradysia. sp. nr. coprophila (Lintner) (Diptera: Sciaridae), larval survival when feeding on the roots of coleus, Solenostemon scutellarioides (L.) Codd, plants. In addition, experiments were conducted to determine the number of rove beetle adults, based on predator:prey ratios, needed to regulate fungus gnat larval populations. In all three experiments, fewer fungus gnat larvae survived in Pro-Mix BX than the Berger BM1 growing medium, and rove beetles reduced the number of fungus gnat larvae in both growing media in the greenhouse experiments. Although predator:prey ratio was not significant, we found that 10 rove beetle adults per 15.2-cm diameter container (1834.82 cm3 with 2.0 L of growing medium) regulated fungus gnat larval populations at the densities investigated. Therefore, greenhouse producers should consider the effects of production practices, such as growing medium type, when using rove beetles to regulate fungus gnat larval populations.

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Attractiveness of Parboiled Rice Hulls to the Fungus Gnat, Bradysia sp. nr coprophila (Diptera: Sciaridae), Adult Relative to Standard Growing Medium Components

HortScience ◽

10.21273/hortsci.44.5.1366 ◽

2009 ◽

Vol 44 (5) ◽

pp. 1366-1369 ◽

Cited By ~ 2

Author(s):

Raymond A. Cloyd ◽

Karen A. Marley ◽

Richard A. Larson ◽

Bari Arieli

Keyword(s):

Steam Distillation ◽

Growing Media ◽

Parboiled Rice ◽

Rice Hulls ◽

Chromatography Analysis ◽

Medium Components ◽

Gas Chromatography Analysis ◽

Growing Medium ◽

Fungus Gnat ◽

The Mean

This study was conducted to assess the attractiveness of growing media containing parboiled rice hulls (PBH) to fungus gnat, Bradysia sp. nr. coprophila (Diptera: Sciaridae), adults. In comparing commercially prepared PBH with peatmoss (LC1) and pine bark (SB200)-based growing media, it was established that the fungus gnat adults were not specifically attracted to any of the growing media, even those containing PBH, with the mean proportion of fungus gnat adults recovered in the sample compartments ranging from 0.16 to 0.23. Moisture content was more important in terms of fungus gnat adult attractiveness to the growing media. In addition, the volatile constituents of the various growing media were determined using a steam distillation procedure. The component that was present in the highest concentration (39.2%) in the dried PBH as determined by gas chromatography analysis was palmitic acid, a straight-chain C16 fatty acid. S8 (cyclo-octasulfur), a well-known odoriferous component of degraded waste materials, was present at a higher concentration (6.2%) in the RH1 growing medium (80% peatmoss) compared with the other growing media evaluated. The data indicate that PBH, when incorporated in certain growing media, do not attract fungus gnat adults, and as such, greenhouse producers can use PBH as an amendment to growing medium without having to be concerned with the prospect of luring fungus gnat adults and sustaining plant damage.

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Overview of undesirable effects of using diatomaceous earths for direct mixing with grains

Pesticidi i fitomedicina ◽

10.2298/pif1602009k ◽

2016 ◽

Vol 31 (1-2) ◽

pp. 9-18 ◽

Cited By ~ 20

Author(s):

Zlatko Korunic

Keyword(s):

Bulk Density ◽

Diatomaceous Earth ◽

Insect Pests ◽

Insect Species ◽

Health Concerns ◽

Stored Product Insects ◽

Grain Moisture ◽

Species Tolerance

Despite numerous advantages of diatomaceous earth (DE), its use for direct mixing with grains to control stored-product insects remains limited because of some very serious obstacles and disadvantages. The main obstacles preventing a wider use of DEs for mixing with grain, such as health concerns, the reduction in bulk density, differences in insect species tolerance to the same DE formulation, the effects of grain moisture and temperature on the effectiveness against insects, the influence of various commodities on DE efficacy, the use of DEs in some other fields, and possible solutions for overcoming DE limitations during direct mixing with grains are described in this manuscript. The same attempts have been made to discover new ways of increasing significantly the effectiveness against insects when much lower concentrations are used for direct mixing with grains. If these newer enhanced formulations can respond to the existing limitations of diatomaceous earth, a wider utilization of diatomaceous earth may be expected to control stored-product insect pests.

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Combining Selenium Biofortification with Vermicompost Growing Media in Lamb’s Lettuce (Valerianella locusta L. Laterr)

Agriculture ◽

10.3390/agriculture11111072 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1072

Author(s):

Lucija Galić ◽

Marija Špoljarević ◽

Alicja Auriga ◽

Boris Ravnjak ◽

Tomislav Vinković ◽

...

Keyword(s):

Organic Waste ◽

Animal Feed ◽

Daily Intake ◽

Leafy Vegetables ◽

Sodium Selenate ◽

Human Populations ◽

Human Diet ◽

Growing Media ◽

Plant Foods ◽

Growing Medium

Leafy vegetables are a daily part of the human diet all over the world. At the same time, a worldwide problem of Se malnutrition is present in human populations, mostly due to low soil Se contents. As plants represent the main source of this element in the human diet, with Se being an essential trace element for humans and animals, plant foods containing Se can be used as an efficient means of increasing the Se in the human diet, as well as in animal feed (biofortification). At the same time, the production of growing media relies on limited peat reserves. The use of earthworms facilitates the production of composted organic masses mostly consisting of organic waste, called vermicompost. The aim of this study was to investigate the influence of three different growing media (commercial peat media, vermicompost, and a 1:1 mixture) on Se biofortification’s efficacy and yield in lamb’s lettuce. The Se biofortification was performed with sodium selenate (Na2SeO4). It was shown that biofortification increased the Se contents such that a mass of only 48.9 g of fresh leaves contained enough Se for the recommended daily intake in human nutrition (55 µg Se/day), which represents a significant potential for solving Se malnutrition. Furthermore, the use of a 1:1 vermicompost–commercial substrate mixture showed a similar performance to the peat growing medium, contributing to the preservation of peat reserves.

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24-Epibrassinolide Restores the Synthesis of Proteins and Amino Acids in Brassica juncea L. Leaves Under Imidacloprid Stress

Journal of Horticultural Research ◽

10.1515/johr-2017-0024 ◽

2017 ◽

Vol 25 (2) ◽

pp. 85-90 ◽

Cited By ~ 4

Author(s):

Anket Sharma ◽

Vinod Kumar ◽

Ashwani Kumar Thukral ◽

Renu Bhardwaj

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Brassica Juncea ◽

Total Protein ◽

Acid Content ◽

Soil Amendment ◽

Insect Pests ◽

Amino Acid Content ◽

Total Proteins ◽

Amino Acid Contents

Abstract Pesticides are applied to protect crops from a variety of insect pests but their application cause toxicity to plants that results, among others, in reduction of protein as well as amino acid contents. The present study is aimed at observing the effect of seed pre-soaking with 24-epibrassinolide (EBL) on the protein and amino acid content in the leaves of Brassica juncea L. grown in soil that is amended with pesticide im-idacloprid (IMI). Soil amendment with IMI resulted in a decrease in the contents in leaves of total proteins and 21 amino acids studied. Seed soaking with 100 nM of EBL resulted in the recovery of total protein as well as amino acid contents in leaves, when compared with plants grown in only IMI amended soils.

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