C.Th. Buchelos

A survey on the mites of stored grain in Greece

Abstract A quantitative and qualitative survey of mites associated with stored products in Greece involved the examination of wheat, maize, barley, wheat flour, bran and residues from three types of storage facilities (silos, farm stores, flour mills). Seventeen species belonging to eleven families and four orders were found. The taxa Androlaelaps casalis casalis (Berlese), Acaropsis docta (Berlese) and Acarophenax sp. were new to the fauna of Greece while Cheyletus eruditus (Schrank), Lepidoglyphus destructor (Schrank). Tyrophagus putrescentiae , Schrank, Tydeus sp., Stigmaeidae , and Bdellidae are recorded for the first time in Greek stored products. The most frequent and abundant taxa were C. eruditus and L. destructor followed by Tydeus sp. Farm stores were the most infested apparently due to the absence of control measures taken in that type of facility.

Efficacy of multisurface traps and Lasiotraps with and without pheromone addition, for monitoring and mass-trapping of Lasioderma serricorne F. (Col., Anobiidae) in insecticide-free tobacco stores

The efficacy of pheromone‐baited multisurface traps and Lasiotraps (fig.) was compared with regards to mass‐trapping male tobacco beetle (Lasioderma serricorne F.) in two insecticide‐free tobacco stores (˜ 15 times 10 times 3 m) in Piraeus (southern Greece) for 15 months (Oct. 1990 through Dec. 1991). Continuous captures of L. serricorne on multisurface traps and Lasiotraps with and without addition of 10 mg anhydroserricornin (2,6‐diethyl‐3,5‐dimethyl‐3,4‐dihydro‐2H‐pyran) revealed a total catch of 720 662 tobacco beetles on 2 pheromone‐baited multisurface traps, 2 pheromone‐baited Lasiotraps as well as 2 multisurface traps and 2 Lasiotraps without pheromone addition. The 2 pheromone‐baited multisurface traps caught 501 481 tobacco beetles (˜ 69.6 %), while the 2 unbaited multisurface traps caught 131 865 L. serricorne (˜ 18.3 %). However, the 2 Lasiotraps with pheromone addition captured 59 265 tobacco beetles (˜8.2 %), whereas the 2 Lasiotraps without pheromone caught 28 051 tobacco beetles (˜3.9 %) only (table 2). It follows that pheromone‐baited multisurface traps caught ˜3.8 times more L. serricorne than multisurface traps lacking pheromone, while multisurface traps provided with pheromone captured ˜8.5 times more tobacco beetles than pheromone‐baited Lasiotraps. Moreover, pheromone‐baited multisurface traps caught ˜ 17.8 times more L. serricorne than pheromone‐free Lasiotraps.

Correlation between the number of adult male Pectinophora gossypiella (Saund.) (Lep., Gelechidae) catches on pheromone traps and the rate of infestation in fruiting bodies of cotton plants by young larvae in three regions of central Greece

In order to evaluate the influence of the number of catches in pheromone‐baited traps on the percentage of larval infestation, six delta traps equipped with sex attractant were placed in each of three regions in Central Greece (Farkadona, Farsala, Almyros) in cotton fields from 20 June until 30 September 1995. The collection of fruiting bodies took place weekly and the counting of adults in the traps was carried out each day. The population fluctuation in all three regions was similar with their peak during the first weeks of August. In Farkadona the infestation level was low (1% at the first sampling of August) with a maximum of 9% in the last sampling of September. In Farsala and Almyros, the infestation level was already high (10% and above) in early August. There was a significant positive linear correlation between the number of moth catches and the infestation percentage from first‐ and second‐stage larvae on the first (R = 0694) and second (R = 0.7399) boll‐feeding generations.

A survey of beetles in store-rooms containing barley and maize for animal feed, on the island of Lefkas, Greece : abundance and population fluctuation of the most significant species

During an 18-month survey on stored barley and maize intended for animal feed conducted in store-rooms on the island of Lefkas, Greece, 21 different taxa of stored product Coleoptera belonging to 12 families were represented in a total of 6027 individuals. The most abundant species were Sitophilus oryzae (L.) and S. granarius (L.). The abundance of each taxon in both products is presented, while their presence in different parts of the stores is commented upon. Finally, the population fluctuations of the 5 most numerically significant taxa are described.

Comparison of four methods for the detection of Coleoptera adults infesting stored wheat: efficiency and detection sensitivity.

In order to evaluate trapping and standard sampling methods for Coleoptera adult detection in bulked wheat, three commercial types of traps (WBII, Pitfall Cone Trap and Grain Probe Trap) and a 2-m long grain trier (9 openings, 750 g capacity) were compared. The comparison, which took place in 9 steel bins containing wheat in Central Greece, indicated that the traps were more effective in detecting adults belonging to the 21 beetle species that were found. Traps contained up to 45 times more adults than the grain trier samples, while at the same time traps produced noticeable levels of detection sensitivity for all species found, as compared to the grain trier samples. For most species, mean trap catches in WBII and Pitfall Cone traps were significantly higher than the means of the other two methods. The correlation coefficient values between trap catches and adult numbers in samples were not significantly different than zero, indicating that the effort to relate trapping to absolute estimation sampling methods is a very complex procedure.

Evaluation of effectiveness of Insegar (fenoxycarb 250 g/kg) WP against Phyllocnistis citrella Stainton (Lep., Gracillariidae) and its effect on Cales noacki How. (Hym., Aphelinidae)

Aiming to control the citrus leafminer Phyllocnistis citrella St. while at the same time protecting the biological equilibrium and mainly the beneficial insect Cales noacki, experiments have taken place in the regions of Argolis and Fthiotis, Greece in 1996 and 1997. Insegar (fenoxycarb) 2 5 WP was applied on young citrus trees. During 1996, the compound, applied every 10 days at a rate of 30 g/hI (with or without adjuvant), gave satisfactory protection from P. citrella without substantially harming C. noacki populations. No phytotoxicity symptoms were observed during the experiments.

Assessment of three killing agents’ impact on the capturing of Coleoptera species infesting stored wheat

The introduction of three killing agents (propylene glycol, DDVP and water) inside perforated probe traps was evaluated for their efficiency in trapping Coieoptera adults infesting stored cereals. The experiment was carried out in nine steel bins containing wheat, located in Central Greece, in August 1997. For the most of the 26 beetle species found, no significant differences were observed among treatments. ForSitophilus spp.,Typhaea stercorea, Aloasverns advena, Oryzae-philus surinamensis, Latheticus oryzae, Palorns ratzeburgii, P. subdepressus, andTenebroides mauritanicus, significantly less adults were found in the control traps (with no killing agent). Significant differences among three killing agents were observed only forT. stercorea andT. mauritanicus. Given that the traps supplied with killing agents were found to contain adults even in locations where control traps did not, is concluded that the addition of killing agents has increased the detection sensitivity of traps.