Alergeni u poljoprivrednim proizvodima tijekom uskladištenja

The increasing occurrence of allergies in the developed countries and greater interest in food safety has drawn attention to the presence of allergens in agro products during storage. Stored agro products can contain allergenic contaminants of plant, microbial, or animal origin. Several stored-product insect and mite species were confirmed as sources of allergens. The most important are storage mites because they cause occupational asthma by inhalation and anaphylactic reactions when ingested in high numbers. The urine of rats and mice can be a significant source of allergens that are mainly present as large airborne particles. Stored moulds are also confirmed as potential source of allergens. However, it is likely that the major problem resulting from the presence of moulds in food will be due to the toxic effects of mycotoxins, rather than allergenic effects. The adoption of good management and processing technique can help to minimise the risk.Na poljoprivrednim proizvodima tijekom čuvanja u različitim skladišnim objektima pojavljuje se niz rizičnih situacija poput kontaminacije grinjama, insektima, glodavcima, plijesnima, nedostatne higijene, uporabe opasnih i toksičnih pesticida, razvoja mikotoksina i alergena. Problemi su osobito naglašeni u zemljama u razvoju gdje su zalihe hrane nedostatne i zbog potrebe za jelom zanemaruju se potencijalne i stvarne opasnosti koje takva hrana može imati za ljudsko zdravlje. Smatra se da dobar sustav integrirane zaštite robe poljoprivrednog podrijetla može znatno smanjiti potencijalnu i stvarnu opasnost nastalu onečišćenjem tijekom čuvanja u skladištima. Porast pojava alergije u razvijenim zemljama i želja da se poveća sigurnost hrane usmjerila je pozornost znanstvenika na mogući razvoj alergena na uskladištenoj poljoprivrednoj robi i u njoj tijekom čuvanja. Istražujući moguće uzroke pojave respiratornih simptoma u radnika zaposlenih u žitarskoj i mlinarskoj industriji, brojnim testovima i u objavljenim radovima potvrđena je uska povezanost između profesionalnih bolesti i kontaminacije uskladištene robe i radnog prostora grinjama, insektima, glodavcima i plijesnima. Uskladišteni proizvodi mogu sadržavati alergijska onečišćenja biljnog, mikrobiološkog i životinjskog podrijetla. Utvrđeno je da su grinje najvažniji onečišćivači robe i proizvođači alergena. Uzrokuju astmu kad se unose u organizam disanjem. Osobito su opasne kad se u velikom broju unose u organizam s hranom jer izazivaju anafilaktičke reakcije. Premda su kao izvori alergena potvrđene i neke skladišne gljivice (Aspergillus oryzae i A. niger), smatra se da su njihovi mikotoksini znatno opasniji problem. Kao izvori alergena navode se ove skladišne grinje i insekti: grinje Dermatophagoides farinae, Lepidoglyphus destructor, Tyrophagus putrescentiae, Tyreophagus entomophagus i Suidasia spp., insekti Tenebrio molitor, Sitophilus granarius, Plodia interpunctella, Ephestia kuehniella, Liposcellis bostrychophila i Blatta orientalis. Izmet artropoda kao i mokraća štakora i miševa jednako su važni izvori alergena

Obrada površinskog sloja zrnene robe s pomoću dijatomejske zemlje radi suzbijanja kukaca

This paper describes an alternative method to synthetic insecticides used for protection of stored agricultural products the purpose of which is to minimise the everyday human exposure to those chemicals. The method uses diatomaceous earth which is practically non-toxic to humans and fully acceptable for the environment. Fifty and 100-cmdeep layers of Hard Red Spring wheat Triticum aestivum (L.) in metal containers (cylinders), 30 cm in diameter and 150 cm in height were treated with 0.5 and 0.75 g of diatomaceous earth Protect-It® per kg of wheat. The treatment reduced the population of Sitophilus oryzae (L.), Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) by 98 to 100% with respect to controls. The conclusion is that a 100-cm-surface layer treated with 0.5 g/kg of Protect-It® is sufficient to control these insects, and that no more than 20% of the total grain mass should be treated to minimise bulk density reduction. A field test using a similar design is essential to confirm the laboratory findings.Koncentracije dijatomejske zemlje potrebne za uspješno suzbijanje kukaca štetnih za uskladišteno žito imaju neželjen, negativan utjecaj na određena svojstva žita, primjerice na hektolitarsku masu i sipkavost, vrlo važne čimbenike koji određuju kakvoću žita. U namjeri da se negativni utjecaj dijatomejske zemlje na žitnu masu smanji, predlaže se obrada samo dijelova žitne mase (obrada slojeva) umjesto obrade cjelokupne mase žita. Pedesetcentimetarski i stocentimetarski površinski slojevi pšenice Triticum aestivum (L.) (Hard Red Spring) u metalnim posudama promjera 30 cm i visokim 150 cm, obrađeni s 0,5 i 0,75 grama Protect-It® po kilogramu pšenice nisu bili dostatni da potpuno spriječe prodor Sitophilus oryzae (L.) i Tribolium castaneum (Herbst) u neobrađeni sloj ispod obrađenog sloja pšenice. Međutim, u usporedbi s neobrađenom masom pšenice (kontrolnim ponavljanjima) populacija obiju vrsta bila je smanjena za više od 99%. Isto tako je u pšenici obrađenoj s Protect-It®, populacija Rhyzopertha dominica (Fabricius) bila smanjena za više od 98%, a istodobno je prodor kukaca u donji neobrađeni sloj pšenice bio potpuno spriječen. Zaključuje se da se obradom 100 cm dubine površinskog sloja pšenice s 0,5 g dijatomejske zemlje Protect-It® po kilogramu postiže zadovoljavajuća zaštita i sprječava infestacija robe sa S. oryzae, T. castaneum i R. dominica. Da bi se znatno umanjio negativni utjecaj dijatomejske zemlje na smanjenje hektolitarske mase, predlaže se obrada samo dijela zrnene mase, ne više od 20% od ukupne mase robe. Smatra se da se ovim postupkom uskladištena neinfestirana pšenica može na zadovoljavajući način zaštititi od štetnika skladišta i da ovaj postupak može uspješno zamijeniti obradu cjelokupne mase robe s dijatomejskom zemljom. S obzirom na gotovo zanemarivu toksičnost i opasnost dijatomejske zemlje za ljudsko zdravlje, uz djelotvornost na kukce koja je usporediva s djelotvornošću znatno otrovnijih i opasnijih sintetskih insekticida koji se rabe u skladištima, važno je naglasiti da je uporaba dijatomejske zemlje u zaštiti uskladištenih žitarica prihvatljiva kako za zaštitu ljudskog zdravlja tako i za očuvanje okoliša

THE INTERACTION BETWEEN PLASMODIOPHORA BRASSICAE WOR. AND HETERODERA CRUCIFERAE FRANKLIN

The club root organism - Plasmodiophora brassicae Wor. is a widespread disease of cabbage in the surrounding of Varaždin (Croatia). In the same region cabbage nematode - Heterodera cruciferae F. is very widespread in soil too. By investigating the relation between nematode and fungus on a cabbage the following conclusion came out: infestation of cabbage with a club root organism has a negative influence on the development of a cabbage nematode population

Osvrt na prirodne insekticide na bazi dijatomejske zemlje

The efficacy of diatomaceous earth (DE) formulations against insect pests is greatly influenced by environmental conditions. It is effective only under dry conditions and becomes wholly ineffective if it is wet. High air relative humidity and especially rain greatly reduce or completely destroy the efficacy of DE when used outdoors. Furthermore, depending on the insect species and commodity treated, DE takes from one to several days to kill insects, even in a dry environment. Because of these factors, DE is in limited use outdoors, especially in regions with a high precipitation. The main uses of DE are for the protection of stored agricultural products against insect infestation, in food industry for structural treatment and for indoor use against some household insects living in a dry environment. The mode of DEs action against insects, the effect of humidity and moisture on DE efficacy, brief overview of the research of DE use in stored grain protection and attempts to overcome DE limitations with combined use of DE and other reduced-risk methods with the insecticide activity for direct mixing with grains are discussed in this article.Klimatski uvjeti imaju značajan utjecaj na djelotvornost dijatomejske zemlje (DZ). DZ je djelotvorna u suhim uvjetima i postaje praktično nedjelotvorna na štetne kukce u vlažnoj okolini. Visoka relativna vlaga zraka i oborine na otvorenome, kao i visoka vlaga zrnate poljoprivredne robe, smanjuju ili u potpunosti eliminiraju djelotvornost DZ-a na štetne kukce. Također, ovisno o vrsti kukaca, kao i o vrsti tretirane zrnate robe, početna je djelotvornost spora i niska te, da bi se ostvarila zadovoljavajuća djelotvornost, izloženost štetnih kukaca na tretiranoj robi trebala bi biti tijekom više dana. Uporaba DZ-a u vanjskome prostoru, naročito u područjima s obilnim oborinama, ne daje zadovoljavajuće rezultate. Stoga, glavna je uporaba DZ-a u zaštiti uskladištenih poljoprivrednih proizvoda, u industriji hrane, za obradu raznih površina i za suzbijanje štetnika u zatvorenome prostoru. Način djelovanja DZ-a na štetne kukce, utjecaj relativne vlage zraka i vlage robe na djelotvornost, sažeti pregled istraživanja djelovanja DZ-a u zaštiti uskladištenih žitarica, kao i istraživanja o mogućnosti smanjenja negativnog utjecaja na tretiranu robu, s kombiniranom primjenom DZ-a i drugih insekticidnih metoda smanjenoga rizika razmatraju se u ovome članku

EFFECTIVNESS OF PURE DIATOMACEUS EARTH AND DIFFERENT MIXTURES OF DIATOMACEUS EARTH WITH PYRETHRINS

U radu su prikazani rezultati laboratorijskih pokusa na uskladištenoj mekanoj pšenici infestiranoj s dvije vrste skladišnih kukaca: rižin žižak - Sitophilus oryzae L. i kestenjasti brašnar - Tribolium castaneum Herbst., obrađenoj kombinacijama mješavina dijatomejske zemlje (DZ) i piretrina (Diatect V, Diatect II, Bug-B-Gon, Perma-Guard D-20) i DZ bez piretrina (Protect-It, Perma-Guard i DZ iz Hrvatske). Rezultati su pokazali opravdanost mješavina DZ i piretrina, jer su značajno djelotvornije na test kukce u odnosu na DZ bez piretrina. S obzirom na to da Hrvatska ima nalazišta DZ-a i autohtoni buhač, moguće je mješavinom DZ i piretrina razviti ekološko prihvatljiv hrvatski insekticid za domaće potrebe, a, isto tako, i za izvoz u druge zemlje.This study shows results of laboratory experiments on stored soft white wheat infested with two stored pest species: rice weevil - Sitophilus oryzae (L.), and red flour beetle - Tribolium castaneum (Herbst), treated with different mixtures of Diatomaceus earth (DE) and pyrethrins (Diatect V, Diatect II, Bug-B-Gon, Perma-Guard D-20 ), and DE without pyrethrins (Protect-It, Perma-Guard and DE from Croatia). The obtained results confirmed that the mixture of DE and pyrethrin and PBO is useful against test-insects and generated significantly higher effectiveness when compared with the results obtained with DE without pyrethrins. Due to the fact that Croatia has the sources of good DE and indigenous Dalmatian pyrethrum, it is possible to develop and produce safe, natural and ecologically acceptable Croatian insecticide by using mixture of DE and pyrethrins, for domestic market and export

EFFECTIVNESS OF PURE DIATOMACEUS EARTH AND DIFFERENT MIXTURES OF DIATOMACEUS EARTH WITH PYRETHRINS

U radu su prikazani rezultati laboratorijskih pokusa na uskladištenoj mekanoj pšenici infestiranoj s dvije vrste skladišnih kukaca: rižin žižak - Sitophilus oryzae L. i kestenjasti brašnar - Tribolium castaneum Herbst., obrađenoj kombinacijama mješavina dijatomejske zemlje (DZ) i piretrina (Diatect V, Diatect II, Bug-B-Gon, Perma-Guard D-20) i DZ bez piretrina (Protect-It, Perma-Guard i DZ iz Hrvatske). Rezultati su pokazali opravdanost mješavina DZ i piretrina, jer su značajno djelotvornije na test kukce u odnosu na DZ bez piretrina. S obzirom na to da Hrvatska ima nalazišta DZ-a i autohtoni buhač, moguće je mješavinom DZ i piretrina razviti ekološko prihvatljiv hrvatski insekticid za domaće potrebe, a, isto tako, i za izvoz u druge zemlje.This study shows results of laboratory experiments on stored soft white wheat infested with two stored pest species: rice weevil - Sitophilus oryzae (L.), and red flour beetle - Tribolium castaneum (Herbst), treated with different mixtures of Diatomaceus earth (DE) and pyrethrins (Diatect V, Diatect II, Bug-B-Gon, Perma-Guard D-20 ), and DE without pyrethrins (Protect-It, Perma-Guard and DE from Croatia). The obtained results confirmed that the mixture of DE and pyrethrin and PBO is useful against test-insects and generated significantly higher effectiveness when compared with the results obtained with DE without pyrethrins. Due to the fact that Croatia has the sources of good DE and indigenous Dalmatian pyrethrum, it is possible to develop and produce safe, natural and ecologically acceptable Croatian insecticide by using mixture of DE and pyrethrins, for domestic market and export

LABORATORY TESTS ON INSECTICIDAL EFFECTIVENESS OF DISODIUM OCTABORATE TETRAHYDRATE, DIATOMACEOUS EARTH AND AMORPHOUS SILICA GEL AGAINST Sitophilus oryzae (L.) AND THEIR EFFECT ON WHEAT BULK DENSITY

Istraživali smo insekticidnu učinkovitost tri različita inertna prašiva: dinatrijev oktaborat tetrahidrat (DOT) i dijatomejsku zemlju (DZ) Celatom® Mn 51 primijenjenih kao prašivo i suspenzija i silika gel Sipernat® 50 S u obliku prašiva na Sitophilus oryzae (L.) te njihov utjecaj na smanjenje hektolitarske mase. Sipernat® 50 S bio najučinkovitije je prašivo s vrlo brzim inicijalnim djelovanjem. DZ i DOT imaju sličnu učinkovitost na S. oryzae. DOT je imao nisko inicijalno djelovanje, no nakon produženog izlaganja od 8., a osobito 21. dana, mortalitet je vrlo visok (100%), slično djelovanju DZ-a. Sličan slijed prašiva zabilježen je i kod utjecaja na smanjenje hektolitarske mase. Pri dozama od 200 i 500 ppm, najmanju razliku u hektolitarskoj masi u odnosu na hektolitarsku masu netretirane pšenice imao je DOT (-1,1 i -1,9 kg hl-1, kako slijedi), potom Celatom® MN 51 (-3,5 i -4,3 kg hl-1, kako slijedi) te Sipernat® 50 S (-5.2 i -5.5 kg hl-1, kako slijedi). Zbog takvog učinka na hektolitarsku masu pšenice, DOT pripada u skupinu s najslabijim negativnim učinkom na hektolitarsku masu i stoga je obećavajuće prašivo u suzbijanju štetnika na uskladištenoj pšeniciWe examined insecticide effectiveness of three different inert dusts: disodium octaborate tetrahydrate (DOT) and diatomaceous earth (DE) Celatom® Mn 51 applied as powder and suspension, and silica gel Sipernat® 50 S applied as powder against Sitophilus oryzae (L.) and their reduction of grain bulk density. Sipernat® 50 S was the most effective dust with a very fast initial effectiveness. DE and DOT generated similar effectiveness against S. oryzae. DOT generated low initial effectiveness but after prolonged exposure time of 8 and especially after 21 days, the mortality was very high (100%), similar to the effectiveness of DE. The similar order of dusts was obtained in the reduction of wheat bulk density. Applied at dose of 200 and 500 ppm, the lowest bulk density difference in regard to bulk density of untreated wheat had DOT (-1.1 and -1.9 kg hl-1, respectively), followed by Celatom® Mn 51 (-3.5 and -4.3 kg hl-1, respectively) and Sipernat® 50 S (-5.2 and -5.5 kg hl-1, respectively). Due to the effect on wheat bulk density DOT belongs to the group with the least negative effect on bulk density and therefore, it is a promising dust to control stored grain insect pests

Croatian diatomites and their possible application as a natural insecticide

In recent decades, there has been an increase in the use of diatomaceous earth (DE) as a natural insecticide because of its low mammalian toxicity, worker safety, low risk of food residues and the occurrence of resistant insect populations associated with the use of chemical insecticides.Therefore there is potential for research into known but previously undescribed Croatian mid-Miocene marine diatomites from the perspective of their potential as proper DE that could be mixed with plant extracts as a new formulation for grain storage protection. The marine diatomites belong to the Paratethyan near shore environment, deposited in the upwelling zone during a mid-Miocene temperate climate. Palaeontological, mineral and geochemical analyses were done on ten promising marly sediments from 26 outcrops and one borehole from the North Croatian Basin. The most important ingredient of diatomaceous sediments is silica (biogenic opal-Aand SiO2 bound in other silicate minerals including quartz, clay minerals, micas, etc.). The amorphous silica content of the tested Croatian diatomites is relatively low (<50%) in comparison with the Celatom® MN 51 standard (medium to high efficient DE) (73.6%), nevertheless they show insome part even slightly better efficacy against insects. It seems that the enhanced content of smectite in diatomaceous sediments also influences increased absorption of DE. Based on palaeontological results, the most efficient diatomites from the Podsusedsko Dolje and Markuševec (Medvednica Mt.) consist of the mid-sized planktonic Coscinodiscus group of species whereThalassionema nitzschioides dominate and is positively correlated with their absorption. The usage of Boströms’ standard formula for getting opal-A from geochemical data was abandoned because of negative results and the modified Murdmaas’ formula for hemipelagic sediments was applied. Preliminary results on the aforementioned diatomite (as inert dusts) show good efficacy against tested insects Sitophilus oryzae (LINNAEUS), Tribolium castaneum (HERBST) and Rhyzopertha dominica (FABRICIUS).</p

CHEMICAL CONTROL OF THE CABBAGE NEMATODE - HETERODERA CRUCIFERAE FRANKLIN IN NURSERIES

In the autumn of 1972 and in the spring of 1973 of we arranged experiment with nematocides in the nursery at Futog to find a possibility of chemical control methods againt the cabbage nematode – Heterodera cruciferae Franklin. The following preparation were applied: DD Soil Fumigant in the dose of 300 l/ha and 500 l/ha, Basamid granulat in the dose of 40 g/m² and 60 g/m², Di Trapex CP in the dose of 300 l/ha and 750l/ha and Terabol (CH₃Br) in the dose of 50 g/m². The best results were obtained by applying Terabol and Basamid in the dose of 40 g/m². DD Soil Fumigant in the dose of 500 l/ha, applied in the autumn produced phytotoxic symptoms on seedling of cabbage. Aplication of Basamid in the dose of 60g/m² in the autumn produced also phytotoxic symptoms but considerably poorer in relation to symptoms on seedlings from plots treated with DD Soil Fumigant

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

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