Arthropod Infestation in Samples of Stored Seeds in the Czech Republic

Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16

Z�� KUČEROVÁ and P�� HORÁK

Department of Stored-Product Pest Control, Division of Phytomedicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic

Abstract: Twenty-one types of seed samples (mainly vegetable and grass seed) were analysed in laboratory and 60% arthropod infestation (14 Acarina, 5 Psocoptera species) was found. The seeds of beet, grass, onion, radish and lettuce were most sensitive to infestation. Acarus siro was a dominant mite pest from all aspects (frequency, abundance and seed diversity infestation), followed by Tyrophagus putrescentiae, Tarsonemus granarius and Lepi- doglyphus destructor. Cheyletus eruditus was a dominant predatory mite. Lepinotus patruelis was the most frequent psocid pest.

Key words: mites; psocids; Acarina; Psocoptera; stored seed; stored product pests

Many mites and psocid species are well known as rina, Psocoptera). We determined the species and stored-product pests of various agricultural com- examined population density. The whole analysed modities. Papers concerning faunistic research of samples (ca 10–100 g) were placed on Tullgren pests of stored seeds in the Czech Republic are funnel (exposure time 24 h) to extract arthropods. focused mainly on arthropod occurrence in stored Extracted specimens were counted individually grain or food commodities (Ž�� 1967, 1998; or with the use of Solomon’s method (S�� Z�� et al. 1984; W�� et al. 1999; S�� et al. 1945). Mite and psocid species were determined 2003; K�� et al. 2003). However, comprehen- under the microscope on slides. Determination was sive research on arthropod occurrence in stored done mainly according to G�� (1974), H�� seeds has not been conducted yet, except several (1976) and L�� (1990, 1998). The abundance minor notes on seed infestations in Ž�� (1967) of particular species was recalculated per kg of and O�� (1978). To fill this gap, the presented pa- seed to become comparable. per brings a survey of arthropod infestation of 21 seed types (mainly vegetable and oil seed, grass RESULTS seed and seed outlets). The infestation was de- tected in seed samples analysed during the years Arthropod diversity and types of seeds 1999–2003 at the Department of Stored-Product Pest Control , Research Institute of Crop Produc- Altogether 19 species were identified in seed tion. These samples were sent to this laboratory samples. Out of these, 14 were mite species (As- for species diagnostics from various seed stores tigmata 4, Prostigmata 6, Mesostigmata 4) and in the Czech Republic. 5 psocid species. A detailed list of arthropod species and their occurrence on particular seed types MATERIAL AND METHODS are presented in Table 1. The greatest diversity of species was found on beet (10 species), followed Altogether 201 samples of 21 seed types were by grass (9), onion (9), radish (8) and lettuce seed analysed in laboratory for pest infestation (Aca- (7). The ratio of pest to beneficial arthropod species

Supported by the Ministry of Agriculture of the Czech Republic, Project No. MZE 000 27 00 603.

11 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16 -

So 140 200 770 60 000 ), Ra – ra – Ra ), 3 69 37 66 50 Gs 278 2 273 1 300 17 521

15 Po Raphanus sativusRaphanus

Li 60

60 60 Co 612 312 ), Ru – runch ( runch – Ru ),

30 Sw

10 10 40 20 40 Sp Pastinaca sativaPastinaca 6 46 28 Le 200 248 254 1 496 5 87 48 42 60 43 30 Be 293 176 165 ), Pt – parsnip ( parsnip – Pt ), 3 60 55 68 60 Ra 168 101 102

20 Ru 357 160

Pt 50 Petroselinum hortense Petroselinum

60 Pa

Ct 330 1 058

12 91 Ko 146

96 27 Ka 109 2 2 2 4 5 23 20 11 0n 100 ), Ko – kohlrabi, Ct – carrot, Pa – parsley ( parsley – Pa carrot, – Ct kohlrabi, – Ko ), (Schrank) (Schrank) (Berlese) Brassica oleraceaBrassica Lindquist Oudemans (L.) Baker Enderlein (Berlese) Fox (Heymons) Sig Thor Pearman (Schrank) Rohdendorf (Pearman) (Oudemans) L. Table 1. Mite and psocid species and Table their occurrence in particular seed types (number of specimens/kg of infested sample) of seed Type ACARINA Acaridae Acarus siro Acarus farris putrescentiae Tyrophagus Glycyphagidae Lepidoglyphus destructor Tarsonemidae granarius Tarsonemus Tydeidae interruptus Tydeus Cheyletidae Cheyletus aversor Cheyletus eruditus Cheyletus malaccensis Cheyletus hendersoni Dermanyssidae casalis Androlaelaps Haemogamasus pontiger Ascidae Bla�isocius keegani Oribatidae PSOCOPTERA Liposcelididae Liposcelis decolor Liposcelis corrodens Trogiidae Lepinotus reticulatus Lepinotus patruelis Lachesillidae Lachesilla pedicularia ( kale – Ka onion, – On dish, Gs Be – – grassbeet, seed, Le – Sole�uce, – seed Sp outlet – spinach, SwLi ––Co- poppy, swede, linseed,– coriander, Po

12 13 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16

8 □ pests ■ predators and parasitoids 16 s e s p e i y c 6 t 12 e d p e s e f s o 4 f 8 r o e r b e b m u

2 m 4 N u N 0 0 On Ra Be Le Gr A.s. T.p. L.d. T.gr. C.er.

Seed type Main species

Figure 1. Ratio of pest to beneficial arthropod species Figure 2. Spectrum of seed types infested by the main in frequently infested seed types mite species (A.s. – Acarus siro, T.p. – Tyrophagus putrescentiae, L.d. – Lepidoglyphus destructor, T.g. – Tarsonemus granarius, C.e. – Cheyletus eruditus)

occurrence in these seeds is shown in Figure 1. Seed was the most frequent psocid (5%). The mite A. siro outlet, seed of spinach and coriander were infested occurred in 49% of samples together with their by 5–4 species. Absolutely no species were found predator C. eruditus and in 51% of samples with- on the seed of cabbage, scorzonera (S. hispanica), out predator. Average abundance of arthropod dill and clover. The remaining types of seed were species (a) and groups (b) found in seed samples infested with 1 to 3 species (Table 1). A. siro infested of three categories (vegetable and oil seed, grass the highest number of seed types (11) from all pest seed, seed outlets) is shown in Figure 5. Gener- mites. The predator mite C. eruditus was located ally, mites were three times more abundant than in 13 seed types (Figure 2). psocids in vegetable and oil seed and 1.4 times more abundant in grass seed. In seed outlets Frequency and abundance of arthropods in seed samples 50 Arthropod infestation was found in 60% of all analysed seed samples (201). The individual sam- 40 ples were infested with 0 to 5 species (Figure 3). Frequency of Acarina (86.8%) and Psocoptera species in infested samples is shown in Figure 4. A. siro 30 and C. eruditus were the most frequent (38% and 40%), followed by T. putrescentiae (25%). L. patruelis 20 % of infested samples 50 10 40 s e l p 30 0 m a s f

o 20 %

10 Acarus siro

0 Cheyletus eruditus Lepinotus patruelis 0 1 2 3 4 5 Tarsonemus granarius Lepidoglyphus destructor Number of species Tyrophagus putrescentiae Figure 3. Frequency of multiple species infestation in Figure 4. Frequency of the main arthropod species in seed samples infested seed samples

12 13 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16

(a) 10000 □ vegetable seed ■ grass seed

1000

100

1 Oribatidae ACARINA Acarus siro Acarus farris Mesostigmata PSOCOPTERA Liposcelis decolor Cheyletus aversor Cheyletus eruditus Lepinotus patruelis Tydeus interruptus Blattisocius keegani Liposcelis corrodens Androlaelaps casalis Lachesila pedicularia Lepinotus reticulatus Cheyletus hendersoni Lachesillapedicullaria Cheyletus malaccensis Tarsonemus granarius Haemogamasus pontiger Lepidoglyphus destructor Tyrophagus putrescentiae

(b) Analysed Infested Mite pests Mite predator Total mite Psocid pests Type of sample samples samples abundance abundance abundance abundance No. No. (mean ± SD) (mean ± SD) (mean ± SD) (mean ± SD) Vegetable and oilseed 174 105 224 ± 161 47 ± 51 113 ± 140 43 ± 45 Grass seed 24 13 1304 ± 1466 66 ± 112 941 ± 1 336 675 ± 625 Seed outlet 3 3 20113 ± 28204 770 ± 530 12 390 ± 23 809 –

Figure 5. Abundance of particular species (a) and arthropod groups (b) found in seed samples (number of specimens per kg of infested sample) only mites were found (average abundance of species also infested greatest diversity of seed 12.390 specimens/kg). The pest:predatory mite types. C. eruditus occupied the same position in ratio was 5:1 (vegetable seed), 20:1 (grass seed) the category of predatory mites. These findings and 26:1 (seed outlets). are in accordance with the fact that these species are generally the most important and frequent DISCUSSION stored-product mites in grain and other food commodities (Ž�� 1967; C�� 1996). A. siro was found to be both the most prevalent The other mite species found in seed samples are and most abundant mite pest in seed samples. This also common in other stored products. The only

14 15 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16 Czech J. Genet. Plant Breed., 40, 2004 (1): 11–16

exception is a rare predatory mite C. hendersoni, fungal carriers in stored grain habitats. Exp. Appl. which was reported from the Czech Republic only Acarol., 29: 69–87. once – in a sample of wheat and millet (Ž�� H�� A.M. (1976): The Mites of Stored Food and 1979). Houses. MAFF, London. In the case of psocids, the most frequent species G�� K.K. (1974): Staubläuse, Psocoptera. Die in seed samples was L. patruelis. On the other hand, Tierwelt Deutschlands, 61. G. Fischer Verlag, Jena. L. decolor was the most frequent and abundant spe- K�� Z. (1999): Vulnerability of wheat varieties cies in recent years in grain stores (S�� et al. to stored-product psocids. In: Proc. 7th IWCSPP, Oct. 2003). 1998, Beĳing, China, Vol. 2: 1251–1254. The most frequent predatory mite C. eruditus K�� Z. (2002): Weight losses of wheat grains preys mainly on acaroid mites, especially on A. siro, caused by psocid infestation (Liposcelis bostry- (Ž�� 1991), but it can also occasionally prey chophila: Liposcelididae: Psocoptera). Plant Protect. on psocids (K�� 2003). The ratio of A. siro Sci., 38: 103–107. occurrence in samples alone and together with K�� Z. (2003): Stored product psocids as one of their predator was about 1:1. The occurrence and the preys of the predatory mite Cheyletus eruditus abundance of C. eruditus depends on various en- (Schrank) (Acarina: Cheyletidae). In: Conf. IOBC/ vironmental factors; one of them is the population WPRS Working Group Integrated Protection of density of its prey (L�� et al. 2002). Stored Products. Kusadasi, Turkey, Sept. 2003. Acaroid mites and psocids pose agricultural and Book Abstracts: 54. medical problems (S�� et al. 2002). They can K�� Z., A�� R., S�� V. (2003): Accumula- damage various stored commodities. In the case of tion of pest-arthropods in grain residues found in an grain and other seeds, the harm is mainly done to empty store. Z. Pflkrank. Pflschutz, 110: 499–504. the germ (Ž�� 1996; K�� 1999, 2002). L�� C. (1990): Revision of the Western Palaearctic The presence of arthropods in stored commodities species of Liposcelis Motschulsky (Psocoptera: Lipo- is also connected with their interactions with fungi scelididae). Zool. Jb. Syst., 117: 117–174. (S�� 1968; Ž�� 1996; S�� et al. 2002; L�� C. (1998): Psocopteres Euro-Méditerranéens. H�� et al. 2003). Damage to the seed germ due Faune de France 83, Paris. to arthropod – fungi interactions leads to a decline L�� J., J�� V., H�� J., S�� V., Ž�� E. of seed germination. (2002): The population density of the predatory mite It is evident from our results that prevention of Cheyletus eruditus in grain samples infested by stor- losses during seed storage require an early detec- age mites and psocids. In: Book of Abstracts 7th Eur. tion of pest infestation. This is urgent especially in Congr. Entomology, Oct. 7–13, 2002, Thessaloniki, the case of highly susceptible seed types, such as Greece. seed of beet, onion, lettuce, radish and grass. The O�� S. (1978): Psocoptera of food-processing plants heavy infested outlets are also a potential source and storages, dwellings and collections of natural of seed reinfestation. If predatory mites are absent objects in Czechoslovakia. Acta Entomol. Bohemosl., or in low abundance in stored seeds, it is benefi- 75: 226–242. cial to artificially add C. eruditus as a preventive S�� R.N. (1968): Adaptive significance of myco- biological agent (Ž�� et al. 1998). phagy in stored-product Arthropoda. Evalution, 22: 785–798. Acknowledgements. We wish to thank to Dr. E. Ž�� S�� M.E. (1945): Tyroglyphoid mites in stored for determination of mites and valuable comments. products. Methods for the study of population density. Ann. Appl. Biol., 32: 71–75. S�� V., H�� J., K�� A. (2002): Associ- References ated-food-hazards: storage fungi and mites in poppy, mustard, le�uce and wheat. Proc. 6th Conf. C�� S. (1996): Determination, distribution and EFPP 2001, Prague. Plant Protect. Sci., 38 (Special hosts of Acarina group harmful and useful on stored Issue 2): 673–680. products in the province of Edirne. Turkiye Entomol. S�� V., H�� J., K�� Z., M�� Z., Dergisi, 20/3: 199–210. L�� J., Ž�� E. (2003): The influence of type H�� J., S�� V., K�� A., M�� Z., of storage on pest infestation of stored grain in the V�� M., Ž�� E. (2003): Mites as selective Czech Republic. Plant Soil Environ., 49: 55–62.

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W�� P., K�� Z., S�� V., Ž�� E. Ž�� E. (1991): Stored product acarology. In: D��- (1999): Stored product pests in stored grain in the �� F., B�� V.: Modern Acarology. Academia, Czech Republic. In: Proc. 7th Int. Working Conf. Stored Prague, 1: 211–218. Product Protection, Beĳing, China, 1998: 64–68. Ž�� E. (1996): The effect of mites on germination Z�� J., Č�� E., K�� Z., Ž�� E. (1984): of seed. Ochr. Rostl., 32: 175–179. Roztoči a hmyz vyskytující se v československých Ž�� E. (1998): Mite fauna of stored grain in the pšeničných mlýnech. In: Sbor. Ref. IX. čs. Konf. Ochr. Czech Republic. Plant Protect. Sci., 34: 49–52. Rostl., Brno, 30.8.–1.9.1983: 141–142. Ž�� E., A�� C., S�� M. (1998): Personal Ž�� E. (1967): Stored food mites in Czechoslo- experience with biological control of stored food- vakia. J. Stored Prod. Res., 3: 155–175. mites. Bull. OILB-SROP, 21: 89–93. Ž�� E. (1979): Cheyletid fauna associated with stored products in Czechoslovakia. J. Stored Prod. Received for publication February 26, 2004 Res., 15: 11–16. Accepted a�er corrections March 30, 2004

Souhrn

K�� Z., H�� P. (2004): Výskyt členovců ve vzorcích skladovaných osiv v České republice. Czech J. Genet. Plant Breed., 40: 11–16.

Byly prováděny rozbory vzorků osiv (21 druhů, celkem 201 vzorků) na výskyt skladištních členovců. Celkově bylo napadeno 60 % analyzovaných vzorků. Bylo determinováno 14 druhů roztočů (Acarina) a 5 druhů pisivek (Psoco- ptera). Osiva řepy, trav, cibule, ředkvičky a salátu byla vůči napadení skladištními škůdci nejnáchylnější. Acarus siro byl dominantním škodlivým roztočem z hlediska četnosti, počtu jedinců na l kg osiva i počtu napadených druhů osiv, následovaly druhy Tyrophagus putrescentiae, Tarsonemus granarius a Lepidoglyphus destructor. Cheyletus eruditus byl dominantní dravý roztoč. Z pisivek se nejčastěji vyskytoval druh Lepinotus patruelis.

Klíčová slova: roztoči; pisivky; Acarina; Psocoptera; skladované osivo; skladištní škůdci

Corresponding author:

Ing. Z�� K��, Výzkumný ústav rostlinné výroby, odbor rostlinolékařství, oddělení ochrany zásob, 161 06 Praha 6-Ruzyně, Česká republika tel.: + 420 233 022 371, fax: + 420 233 310 636, e-mail: [email protected]