Populations of the phorid fly Megaselia halterata on an experimental mushroom unit over four years

Abstract

SUMMARYPopulations of phorid flies on an experimental mushroom unit were sampled simultaneously in both spawn‐running and mushroom cropping‐houses by sticky traps. Comparison between these populations showed that each reached a maximum about August and that the rate of increase, as measured by the ratio between them, varied from 22 × (at the beginning of February and in mid‐August to 115 × (at the beginning of June and the end of December). Population growth within a crop was assessed from the peaks plotted from weekly catches. Three such peaks could be seen, starting from initial numbers which were high, on average, at casing but with little increase after the seventh week of cropping. However, population growth within crops, found by pooling data for different seasons, showed logistic increases though slopes varied from low, for May to June‐spawned crops, to high for October spawning. Wide variations occurred in the proportion of the total flies represented in the initial catches in the first wk after casing.Partial regressions were examined for the numbers caught in cropping‐houses on those taken in spawn‐running rooms throughout the year. Catches for crops spawned during June to September gave lower slopes for high cropping‐house populations. Spawn‐running room catches showed a linear relation with outdoor 9.00 a.m. B.S.T. temperature and cropping‐house numbers a logistic relation, a better fit obtaining with temperatures at spawning rather than 5 wk later during cropping. Catches during spawn‐running were correlated with those during subsequent cropping and these with catches made during the previous crop on the unit, irrespective of site. Since it was bimodal, rate of increase between spawn‐running and cropping‐houses did not correlate with outdoor temperature but revealed some very high catches in winter. Many flies were trapped in the cropping‐houses early in the year when flies were absent from spawn‐running rooms. Evidence for movements within farms is discussed, especially with respect to overwintering of the phorid, which validates routine trapping of both populations.

Activity and distribution of the mushroom phorid fly, Megaselia halterata, in and around commercial mushroom farms

“…The mushroom phorid fly, Megaselia halterata (Wood) (Diptera: Phoridae), is a key pest in mushroom farming in most parts of the world (Richardson & Hesling, ; Keil, ). Studies on the mushroom phorid fly have focused on its life history within mushroom growing houses, but little is known about the activity of M. halterata outside mushroom growing houses, including nearby residential neighborhoods where the fly can become a serious nuisance to homeowners (Binns et al., ). Mushroom growing is performed inside growing rooms, where M. halterata populations fluctuate throughout the year.…”

“…Megaselia halterata are obligate fungal feeders (Scheepmaker et al., ), and hence females are attracted to spawned mushroom compost (compost with active mycelial growth) (Tibbles et al., ). Some reports suggest that female phorids enter rooms at ‘spawn run’ (stage in the mushroom production process after which the compost has been ‘seeded’ and the mushroom mycelia are actively growing in the compost) either from outside the mushroom‐growing house or from other growing rooms within the house (Hussey, ; Binns et al, ; Navarro et al., ). Once inside the mushroom house, females lay eggs on the mushroom mycelia growing in the spawned compost, where larvae feed on the mycelia (Keil, ).…”

Mushroom Phorid Flies—A Review

“…Low temperatures, high-speed wind and abundant rainfall were postulated as the main weather factors affecting phorid activity; moreover, the effect of light intensity over fly flying was also reported as a critical factor [51]. However other studies did not find a correlation between meteorological data and the rate of pest increase [52]. Kumar and Sharma [53,54] related maximum phorid fly populations with temperatures of 18.5-25 °C and described a positive correlation between the phorid population and temperature.…”

“…The cultivation of A. bisporus is a phased process in which fungal mycelia is grown in pasteurized compost, and a casing layer of peat or peat substitute is then added (casing practice) to stimulate the production of mushroom fruit bodies [50]. Female phorids are normally attracted to volatiles produced by developing mycelia [52,55,56]. As described by Tibbles et al [4], M. halterata adult females were attracted to composted substrates containing A. bisporus mycelia, and the extent of the response increased with the aging of mycelium in the substrate.…”

Eficacia del insecticida triflumuron en el control de las moscas del champiñón por mallas de sombreo fotoselectivo

“…Entre las principales plagas de los hongos cultivados destacan algunas especies de moscas fóridas y esciáridas que ocasionan tanto daños directos como indirectos: las larvas se alimentan del micelio en desarrollo e incluso de los carpóforos ya formados, por lo que afectan al rendimiento productivo, mientras que los adultos son utilizados como vectores por otras plagas y enfermedades, como el ácaro Brennandania lambi y el hongo Lecanicillium fungicola (Binns et al, 1979;Clift y Toffolon, 1981;White, 1981;Clift y Larsson, 1987;Navarro et al, 2010). La abundancia de moscas en el interior de un local de cultivo y el nivel de daños ocasionados por los mismos están directamente relacionados con la población presente en las etapas iniciales del ciclo: momento de la siembra y días inmediatamente posteriores (Binns et al, 1979). Otro momento también propicio para la infestación por estos dípteros ocurre aproximadamente quince días después, cuando se procede a la aplicación de la mezcla de materiales de cobertura sobre el compost incubado (Scheepmaker et al, 1997a;Navarro et al, 2004).…”