Available on-line at http://www.bjbabe.ro Banats Journal of Biotechnology 2012, III(6),

MONITORING OF THE ENTOMOFAUNA IN ECOLOGICAL CROP ROTATION

DOI: 10.7904/2068 – 4738 – III(6) – 104

Evgeniya D. ZHEKOVA

Institute of Agriculture and Seed Science “Obraztsov chiflik”, 7007 – Rousse, str.”Prof. Ivan Ivanov” № 1, Bulgaria E–mail: [email protected]

Abstract: During the period 2009–2010 a monitoring of entomofauna was performed in environmentally justified crop rotation including rotation of legumes (beans, soybean) and cereals (wheat, wintering oats) in two variants–control (without fertilization), and foliar fertilization by Humustim humate fertilizer. Conventional entomological methods were used for determination of species and population density of harmful plants and their entomophaga. The results were processed by crops. Differences in species composition of entomofauna were found in variants fertilized by Humustim, compared to those without fertilization. In no one of the four crops pests in density over Economic Threshold Level (ETL) were detected. Diversity of entomophaga was explained via the favorable ecological environmental conditions and namely by the presence of the trophic factor and the lack of chemical treatments with insecticides.

Keywords: entomofauna, ecological crop rotation.

Introduction cereals under conditions of organic Cereals and legumes are significant farming. structure–defining crops. Because of their wide spread in Material and methods agriculture, their pests and the chemicals The investigation was conducted for control were explored in details during the period 2009–2010 at the [DONCHEV, 1961; DERIMANOV, 1962; KRUSTEVAQ 1995; Experimental field of Institute of YANKOVA et al, 2004; NIKOLOVA, 2006; DIMITROV, 2008]. agriculture and seed science “Obraztsov But one–sided and long–term chiflik”–Rousse in four–pole crop rotation, application of the conventional plant including growing and rotation of the protection leads to many negative crops–beans, wheat, soybeans and subsequences, as one of them being wintering oats under conditions of organic violation of the biological equilibrium in farming. agrocenosis. The trial started after the Block An alternative of the chemical method in two variants control (without method is the integrated plant protection fertilization) and foliar fertilization by and the organic farming [KAROV, 1999]. humate “Humustim” fertilizer in four The organic farming is becoming replications, harvesting plot being 52,5 more popular because of the m2. contemporary requirements for protecting The growing of crops was according of human and animal health in the the requirements of Ordinance N environment. In the system of the organic 22/04.07.2001 of MAF about organic plant farming it is relied on application of production. appropriate crop rotation, organic In order species composition of fertilizers, biological and agro technical harmful and useful entomofauna to be pest control [STANCHEVA, 2003; STOICHEV, 2004]. determined during the vegetation of The objective of the study was crops, monitoring was performed every species composition and population seven days in clear and calm weather. abundance of harmful and useful A conventional cutting method was entomofauna in ecologically justified crop used with a standard entomological sack rotation, including legumes in rotation with (0,3 x 0,7 x 1,0 m)–25 slopes = 5 m2, as

104 Banat’s University of Agricultural Sciences and Veterinary Medicine from Timisoara, Contact: web: http://www.bjbabe.ro, e-mail: bjb@usab–tm.ro

insects caught were killed and identified participation, subdominant–from 5 to by type. 15%, the secondary–from 1 to 5%. The perambulating method was used for complete monitoring the trial. Results The results were processed by As a result of this investigation it crops. The classification of species was was found: made after BOICHEV, 1975, according which: 1. Oats–The total number of insects the dominant species showed over 15% caught in 2009 was 2317 pcs., and in 2010 – 980 pcs., distributed by as follows:

Number Order 2009 2010 Coleoptera 173 248 Diptera 788 88 Heteroptera 240 118 Homoptera/ suborders Aphididae + Cicadinea/ 871+ 90 103 + 149 Hymenoptera 30 18 Thysanoptera 123 250 Orthoptera 2 5 Lepidoptera 0 1

Table 1. The most commonly found insects in both variants in oats 2009 2010 Insects With fertilization, Without With Without pcs. fertilization,pcs. fertilization,pcs. fertilization, pcs. thrips 44 49 100 150 cicads 45 46 39 110 aphids 348 547 58 103 ladybug 11 6 7 1 caspid grain bug 83 60 40 53 wheat sawfly 0 2 0 4 nabis 1 4 3 7 wheat fly 119 70 33 14

In 2009 alphids /Sitobion avenae L. Of useful insects 14–vesicular and Schizaphis graminum Rond./ and ladybug /Coccinula wheat fly /family Chloropidae/ dominated. quatuordecimpustulata L./ and nabis Thrips /Haplothrips tritici Kurd. and /genus Nabis/ were the most commonly Stenothrps graminum Uzel. / and found. The total number of insects pentatomid eurygaster /Eurygaster registered in the variant with Humustim integriceps Put./ were subdominants. fertilizer in 2009 was 1173 pcs., and in Of useful insects 7–spotted ladybug 2010–491 pcs. In 2009 in the variant / Coccinella septempunctata L. / and without fertilization, 1144 pcs. were nabis /genus Nabis/ were most commonly registered, and in 2010–980 pcs. found. The most commonly found insects In 2010 thrips /Haplothrips tritici in both variants were shown in Table 1. Kurd. and Stenothrps graminum Uzel./ Some differences in species and broad–bean weevil /Bruchus composition of the entomofauna were rufimanus Boh./ dominated. Pentatomid observed by variants. eurygaster /Eurygaster integriceps Put./ In 2009 in variant fertilized with and aphids /Sitobion avenae L. and Humustim the following species were Schizaphis graminum Rond./ were registered, not being found in variant subdominant. without fertilization: cabbage stem flea

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beetle /Psylliodes chrysocephala L./, registered, not being found in variant Sitona beetle /g. Sitona/, flea beetle/ without fertilization: Malachius Phyllotreta atra F./, 14–spotted ladybug bipustslatus L., earth fleahopper /Propylaea quatuordecimpunctata L./, /Phyllotreta armoracia Koch./, beet scale Aelia acuminata L. and dolycoris bug /Cassida nebulosa L./ and 14–spotted /Dolycoris baccarum L./. ladybug /Propylea quatuordecimpunctata In variant without fertilization by L./. Humustim the following species were In the variant without Humustim found, not being registered in variant with fertilizer the following species were fertilization: 14–vesicular ladybug registered, not being found in variant with /Coccinella quatuordecimpustulata L./, fertilization: pea weevil /Bruchus pisorum pea weevil /Bruchus pisorum (pisi) L./, (pisi) L./, wheat sawfly–borrer / Cephus alfalfa plant bug /Adelphocoris lineolatus pygmaeus L./ and tarnish plant bug of g. Goeze./, wheat sawfly–borer / Cephus Lygus. pygmaeus L./, spotted ladybug /Stethorus 2. Wheat–The total number of punctillum Ws./, and cantaris /Cantaris insects caught in 2009 was 1485 pcs., sp./. and in 2010–1005 pcs., distributed by In 2010 in variant fertilized with orders, as follows: Humustim the following species were

Number Order 2009 2010 Coleoptera 138 463 Diptera 271 50 Heteroptera 139 123 Homoptera /suborders Aphididae + Cicadinea/ 358+35 13+194 Hymenoptera 59 14 Thysanoptera 477 130 Orthoptera 2 7 Neuroptera 3 8 Lepidoptera 3 3

Table 2. The most commonly found insects in both variants in wheat 2009 2010 Insects With fertilization, Without With Without pcs. fertilization, pcs. fertilization, pcs. fertilization, pcs. aphids 212 156 10 3 wheat fly 51 17 12 2 wheat sawfly–borrer 6 2 4 1 caspid grain bug 83 60 42 39 thrips 200 312 55 75 wide–bean weevil 26 29 91 118 anisoplia beetle 1 3 5 7 ladybug 6 7 31 15

In 2009 aphids /Sitobion avenae L. Subdominants were: thrips /Haplothrips and Schizaphis graminum Rond./, wheat tritici Kurd. and Stenothrps graminum fly /family Chloropidae/ and thrips Uzel./, green cicads /Cicadella viridis L./ /Haplothrips tritici Kurd. and Stenothrps and 14–vesicular ladybug /Coccinula graminum Uzel./ dominated. Pentatomid quatuordecimpustulata L./. eurygaster /Eurygaster integriceps Put./ The total number of insects found in was subdominant. variant fertilized by Humustim in 2009 In 2010 vetch broad–bean weevil was 836 pcs., and in 2010–469 pcs. 649 /Bruchus rufimanus Boh./ dominated. 106 Banat’s University of Agricultural Sciences and Veterinary Medicine from Timisoara, Contact: web: http://www.bjbabe.ro, e-mail: bjb@usab–tm.ro

pcs. were registered in variant without L./, wheat ear fly /Meromyza nigriventris fertilization in 2009, and in 2010–536 pcs. Meq./ and flea beetle /Phyllotreta atra F./. Insects, the most commonly found In variant without Humustim, the in both variants were shown in Table 2. following species were registered, not In 2009 in variant with fertilization been found in variant with fertilization: by Humustim the following species were Chrysopa carnea Steph., 22–spotted found, not being registered in variant ladybug /Thea vigintiduopunctata L./, 5– without fertilization: large green spotted weevil /Aoromius grasshopper /Tettigonia viridissima L./, quinquepunctatus L./, black wheat dolycoris bug /Dolycoris baccarum L./, sawfly–borrer /Trachelus tabidus F./, Moorish bug /Eurygaster maura L./, blue wheat sawfly–borrer /Cephus pygmaeus corn leech /Oulema lichenis Voet./ and L./ and Psammotettix striatus L.. Telenomus sp. 3. Soybean–The total number of In variant without Humustim the insects, caught in 2009 was 361 pcs., and following species were found, not being in 2010–518 pcs., distributed by orders as registered in variant with fertilization: follows. In 2009 no species is reported in sharp–headed bug /Aelia acuminata L./, numbers that would have been identified common wheat leech /Oulema (Lema) as dominant. melanopa L./, Chrysopa carnea Steph. Subdominant species were: green and tarnishplant bug /Lygus sp./. cicada /Cicadella viridis L./, alfalfa plant In 2010 in variant fertilized by bug /Adelphocoris lineolatus Goeze./ and Humustim the following species were Chrysopa carnea Steph. registered, not being found in variant In 2010 green cicads dominated without fertilization: alfalfa weevil /Cicadella viridis L./. /Phytonomus variabilis Herbst./, dolycoris The total number of insects bug /Dolycoris baccarum L./, 14–spotted registered in variant fertilized by ladybug /Propylea quatuordecimpunctata Humustim in 2009 was 181 pcs., and in 2010–266 pcs.

Number Order 2009 2010 Coleoptera 76 50 Diptera 18 57 Heteroptera 77 102 Homoptera /suborders Aphididae+Cicadinea/ 0+143 8+255 Hymenoptera 14 27 Thysanoptera 11 0 Orthoptera 1 5 Lepidoptera 3 4 Neuroptera 18 10

Table 3. The most commonly found insects in both variants in soybean 2009 2010 Insects With fertilization, Without With Without pcs. fertilization, pcs. fertilization,pcs. fertilization,pcs. cicads 53 75 128 127 nabis 16 20 22 19 Chrysopa carnea 6 12 6 10 broad–bean weevil 7 5 8 8 alfalfa plant bug 5 15 8 8

In 2009–180 pcs. were found in pcs. The most commonly insects found in variant without fertilization, in 2010–252 two variants were shown in Table 3.

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In 2009 in variant with fertilization beet flea beetle /Chaetocnema concina by Humustim the following species were Marsh./. found, not been registered in variant In 2010 the differences in species without fertilization: 7–spotted ladybug composition of the entomofauna by /Coccinella septempunctata L./, dolycoris variants were as follows: in variant by bug /Dolycoris baccarum L./, gall midge Humustimthe following species were /Contarinia medicaginis Kieff./, alfalfa reported–Cantharis sp. and 14–spotted looper /Taphrina (Eubolia) arenacearia ladybug /Propylea quatuordecimpunctata Hb/, Italian locust /Calliptamus italicus L./ L./; in variant without Humustim–pea and Adonia variegata Gz. weevil /Bruchus pisorum (pisi) L./, Nezara In variant without Humustim the viridula L., 7–spotted ladybug /Coccinella following species were registered, not septempunctata L./ and cabage stem flea being reported in variant with fertilization: beetle /Psylliodes chrysocephala L./. grass fly /Chlorops pumilionis Bjerk./, 4. Beans–the total number of clover seed chalchid /Bruchophagus roddi insects caught in 2009 was 681 pcs., and Gus./, Nezara viridula L., Cantharis sp., in 2010–601 pcs. distributed by orders as tarnish plant bug /Lygus pratensis L./ and follows:

Number Order 2009 2010 Coleoptera 165 16 Diptera 18 20 Heteroptera 112 259 Homoptera /suborders Aphididae + Cicadinea/ 0+365 3+286 Hymenoptera 18 12 Lepidoptera 2 0 Neuroptera 1 5

Table 4. The most commonly found insects in both variants in beans 2009 2010 Insects With fertilization, Without With fertilization, Without pcs. fertilization, pcs. pcs. fertilization, pcs. cicads 53 75 128 127 nabis 16 20 22 19 Chrysopa carnea 6 12 6 10 broad–bean weevil 7 5 8 8 alfalfa plant bug 5 15 8 8

In 2009 cicada /Cicadella viridis L./ The most commonly found insects dominated, subdominant species were in both variants were shown in Table 4. broad–bean weevil /Bruchus rufimanus In 2009 in variant fertilized by Boh./ and alfalfa plant bug /Adelphocoris Humustim the following species were lineolatus Goeze./. Nabis / family found, not being registered in variant Nabidae/–39 pcs. and ladybug /family without fertilization: grass fly /Chlorops Coccinellidae/–24 pcs. In total showed the pumilionis Bjerk./, cantharis /Cantharis highest density among useful species. sp./. In 2010 green cicada /Cicadella In variant without fertilization by viridis L./ dominated. Humustim the following species were The total number of insects registered, not being found in variant with registered in variant fertilized by fertilization: Nezara viridula L., lentil Humustim in 2009 was 425 pcs., and in weevil /Bruchus lentis Frol./, Chrysopa 2010–180 pcs. In 2009 in variant without carnea Steph., and 11–spotted ladybug fertilization 256 pcs. were registered, and /Semidalia undecimnotata Schn./. in 2010–132 pcs. 108 Banat’s University of Agricultural Sciences and Veterinary Medicine from Timisoara, Contact: web: http://www.bjbabe.ro, e-mail: bjb@usab–tm.ro

In 2010 the differences in species Discussion composition of entomofauna by variants As a result of the study conducted, were as follows: in variant with fertilization insects were registered, belonging to the by Humustim the species were registered: following orders: Coleoptera, Diptera, Sitona beetle /g. Sitona/ and Chrysopa Heteroptera, Homoptera, Hymenoptera, carnea Steph.; in variant without Lepidoptera, Neuroptera, Thysanoptera fertilization the following species were and Orthoptera. found–cabbage stem flea beetle Representatives of Lepidoptera and /Psylliodes chrysocephala L./, alfalfa plant Orthoptera were insignificant number. bug /Adelphocoris lineolatus Goeze./ and The shares of the orders to which broad–bean weevil /Bruchus rufimanus caught insect species belong during the Boh./. two years of investigation differed in four crops (figure 1).

Figure 1. Shares of orders according to the total catch in cutting with entomological sack In oats, wheat and beans during the In none of four crops in both years first year of investigation a greater of investigation pests in density over TEL number of insects was identified than were not registered. during the second year. The availability of sufficient Only in soybean in 2010 the entomophaga–ladybugs, nabis, kantaris, quantity of entomofauna was greater than etc. was explained by the favorable in the first year. ecological conditions and namely the In cereals a greater number of presence of trophic factor and lack by insects were registered during the first chemical treatments by insecticides. year in fertilized variant, and during the second year–in variant without Conclusions fertilization. In soybean in 2009 the Studies conducted during the period quantity of the insects registered in 2009–2010 in environmentally justified variant with fertilization and in control was crop rotation, including legumes /beans, approximately equal. During the next year soybean/ and cereals /wheat, wintering the difference was insignificant in favor of oats/ showed: variant with fertilization. In beans during 1. Differences in species composition both years the insects in variant with of entomofauna in variants fertilization dominated. fertilized by Humustin compared to Differences in species composition those without fertilization. of entomofauna were observed by 2. In all included in crop rotation variants. crops, the pests registered were in Thrips, aphids and harmful wheat density below the Threshold bug were in greatest number of registered Economic Level. harmful species during both years in both 3. Species composition and variants in cereals, in legumes–cicada population density of useful and lucerne bug. insects are sufficient and appropriate system for control of

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pests below the thresholds of entomofauna in soybean (Glycine max economic harmfulness. L.; Soja hispida Moench) and control of pests of economic significance, PhD Thesis, 2006, Pleven. References 9. Stancheva, I.; Kostov, K.; Main types of 1. Boichev, D.; Biology, 1975, p. 179. ecological systems for agricultural 2. Dimitrov, D.; Harmful and useful production. Ecological agricultural entomofauna in some legumes, PhD farm, 2003, FTU Sofia, pp. 14–17. Thesis, General Toshevo, 2008. 10. Stoinev, K.; Ecological and technological 3. Dirimanov, M.; Pests on forage legumes aspects of the modern agriculture, and grain legumes and their control, 2004, Sofia, pp. 17–27. 1962, Plovdiv. 11. Yankova, V.; Tomlekova, N.; Ilieva, A.; 4. Donchev, N.; A study on the relationship Penchev, E.; Genchev, D.; Bean between time of sowing of wheat, weevil (Acanthoscelides obtectus Say) barley and oats and damages various infestation in common bean types of cereal flies cause on them. In: (Phaseolus vulgaris L.) varieties and Proceedings of DSNII, Tolbuhin, 1961, lines. In: International Conference on 1, pp. 167–183. Horticulture Postgraduate (PhD.) 5. Karov, S.; Popov, V.; Paraskevov, P.; Study System and Conditions in Blagoeva, E.; Transition to organic Europe, 2004, Lednice, Czech farming, HAI Plovdiv, 1999, pp. 17– Republic, Mendel University Brno, pp. 23. 265–272 6. Krusteva, H.; Main harmful cicada species on wheat and barley, Plant protection, Received: September 29, 2012 1995, 7, 23–25. Accepted: October 26, 2012 7. Regulation N 22 dated 4 June 2001 about organic production of plants, plant products and foods of plant origin and its labeling. Updated in the SG v. 68, dated 3 August 2001, amended in SG, v. 13, dated 10 February 2006, Sofia. 8. Nikolova, I.; Study on the harmful

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