Gli autori desiderano ringraziare i membri passati della Fotografico laboratorio: Sam-Kyu Kim, Kathryn Plichta e Victoria Miranda-Thompson per il loro contributo al miglioramento di molti di questi protocolli. Noi riconosciamo il sostegno della National Science Foundation (sovvenzioni IOS-0840932 e IOS-0.724.978) a SP Fotografici.

1. Soil Sample Collection <ol><li> Si consideri che copre una superficie minima di 2-4 m 2 per ogni sito di campionamento. </li><li> Raccogliere campioni di terreno a una profondità di almeno 15 cm (Figura 4). </li><li> Prendere almeno 5 campioni casuali all&#39;interno di questa area. </li><li> Prendere 3 sottocampioni per campione. Seconda dell&#39;obiettivo dello studio, sia combinare sottocampioni o mantenerli separati. </li><li> Collocare ogni campione in un sacchetto di plastica. Considerare doppio insaccamento per evitare perdite di campioni (Figura 4). </li><li> Campioni etichetta con un pennarello indelebile. Includere le seguenti informazioni da ogni sito di campionamento: Informazioni sul sito (compresi località / zona / nome e GPS informazioni coordinare posto), la data, l&#39;habitat, la vegetazione associata, temperatura, altitudine, ecc NOTA: Se necessario, raccogliere e / o registrare la presenza di insetti o altri invertebrati raccolti con il campione per la successiva identificazione. Essi possono rappresentare potenziali naturpadroni di casa al EPN. </li><li> Strumenti di raccolta Pulire accuratamente tra i campioni di lavaggio con acqua e / o disinfezione con il 70% di etanolo o soluzione di candeggina allo 0,5%. </li><li> I campioni in un dispositivo di raffreddamento (8 - 15 ° C) durante il trasporto al laboratorio. </li><li> Prendete una porzione del campione di suolo per l&#39;analisi per ottenere informazioni sulla composizione del suolo, tessitura, umidità, conducibilità elettrica o di altri parametri pedologici desiderati. </li></ol> . 2 Isolamento Nematode da campioni di suolo: Tecnica Insect-baiting <ol><li> Rimuovere eventuali detriti (per esempio., Pietre, pezzi di legno o di corteccia, foglie, ecc.) Raccolti con i vostri campioni per evitare la contaminazione con microrganismi saprobico. </li><li> Aggiungere acqua per inumidire il terreno e agevolare la circolazione dei nematodi. NOTA: Utilizzare un flacone spray per aumentare lentamente il livello di umidità del suolo. </li><li> Posizionare circa 200 a 250 ml di terreno umido in un contenitore di plastica pulito con un coperchio. </li><li> Aggiungi esche insetti. Considerare 5 a 10 insetti alla superficie del suolo di ciascun campione (Figura 5). </li><li> Coprire il contenitore con un coperchio e girare contenitori a testa in giù. </li><li> Mantenere contenitori in un luogo buio a RT (solito, la 22 - 25 ° C). </li><li> Controllare contenitori ogni 2-3 giorni, e rimuovere gli insetti morti. NOTA: aggiungere altri insetti sani per ogni contenitore per un ulteriore adescamento del campione di terreno. </li><li> Rimuovere gli insetti morti dai contenitori. NOTA: Cadavers con un marrone o ocra colorazione di solito sono parassitati da steinernematids, mentre il rosso di cadaveri viola scuro mattoni sono parassitato da heterorhabditids. </li><li> Sciacquare cadaveri in acqua sterile. </li><li> Mettere cadaveri in una trappola bianco modificato per il recupero del nematode progenie (vedi procedura riportata di seguito). </li></ol> 3. Nematode Recovery da cadaveri infetti: Modificato Trappola bianca <ol><li> Posizionare la parte superiore di un diametro di 50 (o 60) mm. Capsula Petri all&#39;interno di una parabola più grande (100 mm). </li><li> Impostare un peccatocarta da filtro circolare gle (Whatman # 1) all&#39;interno del piatto più piccolo. </li><li> Posizionare cadaveri sulla carta da filtro del piatto più piccolo assicurandosi cadaveri non si toccano a vicenda per evitare qualsiasi contaminazione. </li><li> Riempire l&#39;esterno (grande) Scatola di Petri con ca. 20 ml di acqua distillata sterile. Non aggiungere acqua nel piatto che contiene i cadaveri. </li><li> Coprire il grande piatto Petri e il suo contenuto con il coperchio (Figura 6). </li><li> Etichettare i piatti di conseguenza. Aggiungere le seguenti informazioni: nome Nematode (specie / isolato), la data di infezione (infezione data è stata fissata) e quella trappola (questa è la data della trappola è impostato). </li><li> Tenere trappola a RT finché non si verifica emergere di stadi giovanili infettive (IJ). Questo processo può richiedere tra i 10 - 25 giorni a seconda delle specie e / o varietà considerata nematodi. </li><li> Acqua raccolta con IJs rimuovendo il più grande piatto della trappola e versando acqua con nematodi in un bicchiere. </li><li> Consentire nematodi decantare sul fondo della bEaker. Questo processo può richiedere alcuni minuti. </li><li> Versare acqua accuratamente, assicurandosi nematodi rimangono nel fondo del bicchiere. </li><li> Risciacquare nematodi con l&#39;aggiunta di più acqua e permettendo nematodi a decantare. Questa fase può essere ripetuta 2 - 3 volte finché l&#39;acqua è pulita. </li><li> Posizionare sospensione nematode in un pallone di coltura tissutale (250 ml). Mantenere la concentrazione della sospensione di 1.000 - 3.000 nematodi / ml. </li><li> Boccetta Store con sospensione nematode in una stanza fredda o in incubatrice tra i 10 - 20 ° C. NOTA: controllare boccette memorizzati periodicamente durata di EPN è variabile. Di solito steinernematids possono essere conservati per 6-12 mesi senza il bisogno di subcoltura, che heterorhabditids possono richiedere più controlli periodici. </li></ol>

<ol>
	<li>Bedding, R. A., Akhurst, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+technique+for+the+detection+of+insect+parasitic+rhabditid+nematodes+in+soil.">A simple technique for the detection of insect parasitic rhabditid nematodes in soil.</a> Nematologica. 21, 109-110 (1975).</li><li>Boemare, N. E., Akhurst, R. A., Dworkin, M., Falkow, S., Rosenberg, E., Schleifer, K. -. H., Stackebrandt, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Genera Photorhabdus and Xenorhabdus. In The Prokaryotes. , 473-488 (2007).</li><li>Gaugler, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Entomopathogenic Nematology. , (2002).</li><li>Gaugler, R., Kaya, H. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Entomopathogenic Nematode s in Biological Control. , (1990).</li><li>Hazir, S., Keskin, N., Stock, S. P., Kaya, H. K., &#214;zcan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diversity+and+distribution+of+entomopathogenic+nematodes+(Rhabditida:+Steinernematidae+and+Heterorhabditidae)+in+Turkey.">Diversity and distribution of entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) in Turkey.</a> Biodiversit., &amp; Conservation. 12, 375-386 (2003).</li><li>Kaya, H. K., Gaugler, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entomopathogenic+nematodes.">Entomopathogenic nematodes.</a> Annual Review of Entomology. 38, 181-206 (1993).</li><li>Kaya, H. K., Stock, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Techniques in insect nematology. In Manual of techniques in insect pathology. , 281-324 (1997).</li><li>Lacey, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Manual of techniques in invertebrate pathology. , (2012).</li><li>McCoy, C. W., Shapiro-Ilan, D., Duncan, L., Nguyen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entomopathogenic+nematodes+and+other+natural+enemies+as+mortality+factors+for+larvae+of+Diaprepes+abbreviatus+(Coleoptera:+Curculionidae).">Entomopathogenic nematodes and other natural enemies as mortality factors for larvae of Diaprepes abbreviatus (Coleoptera: Curculionidae).</a> Biological Control. 19, 182-190 (2000).</li><li>Meyling, N. V., Eilenberg, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Occurrence+and+distribution+of+soil+borne+entomopathogenic+fungi+within+a+single+organic+agroecosystem.">Occurrence and distribution of soil borne entomopathogenic fungi within a single organic agroecosystem.</a> Agriculture, ecosystem., &amp; environment. 113, 336-341 (2006).</li><li>Poinar, G. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Taxonomy and biology of Steinernematidae and Heterorhabditidae. In: Entomopathogenic Nemtaodes in Biological. , 23-61 (1990).</li><li>Stock, S. P., Gress, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diversity+and+phylogenetic+relationships+of+entomopathogenic+nematodes+(Steinernematidae+and+Heterorhabditidae)+from+the+Sky+Islands+of+southern+Arizona.">Diversity and phylogenetic relationships of entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) from the Sky Islands of southern Arizona.</a> Journal of invertebrate pathology. 92, 66-72 (2006).</li><li>Stock, S. P., Hunt, D. J., Grewal, P. S., Ehlers, R. U., Shapiro-Ilan, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nematode+morphology+and+systematics.">Nematode morphology and systematics.</a> Nematodes as biological control agents. CAB International Publishing. , 3-43 (2005).</li><li>Stock, S. P., Goodrich&#8211;Blair, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entomopathogenic+nematodes+and+their+bacterial+symbionts:+The+inside+out+of+a+mutualistic+association.">Entomopathogenic nematodes and their bacterial symbionts: The inside out of a mutualistic association.</a> Symbiosis. 46, 65-75 (2008).</li><li>Stuart, R. J., Gaugler, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patchiness+in+populations+of+entomopathogenic+nematodes.">Patchiness in populations of entomopathogenic nematodes.</a> Journal of Invertebrate Pathology. 64, 39-45 (1994).</li><li>White, G. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+obtaining+infective+nematode+larvae+from+cultures.">A method for obtaining infective nematode larvae from cultures.</a> Science. 66, 302-303 (1927).</li></ol>

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Questa manifestazione è la prima delle due presentazioni che descrivono una serie di tecniche che sono comunemente usati per lo studio EPN e dei loro batteri simbionti. Queste tecniche rappresentano passaggi fondamentali per la creazione di successo delle culture EPN in laboratorio e costituiscono anche la base per altri biotest che impiegano EPN come organismi modello per la ricerca. Vari sondaggi del terreno di EPN hanno dimostrato che la loro abbondanza e la distribuzione può variare tr...

Molti nematodi sono associati con gli insetti, e le loro interazioni ospite variano da vantaggioso per dannosa. Qui, ci concentriamo su un gruppo di nematodi che sono patogeni di insetti, noto anche come nematodi entomopatogeni (o EPN). Due famiglie di nematodi appartengono a questo gruppo di nematodi: Steinernematidae e Heterorhabditidae 11,13. Il loro effetto patogeno è infatti conferita dalla loro interazione con anaerobi facoltativi batteri enterici (batteri Xenorhabdus associano con steinernematids e batteri Photorhabdus associare a heterorhabditids) 2. I batteri sono vectored da un host ad un altro insetto da parte l&#39;unica tappa libero nematode vita, il giovane infettivo terzo stadio (noto anche come dauer giovanile, giovanile infettiva o IJ), che vive nel terreno. Una volta dentro l&#39;insetto, i nematodi rilasciano i batteri nella emolinfa dell&#39;insetto, che uccidono l&#39;insetto ospite da una massiccia setticemia. I batteri anchedegradare i tessuti dell&#39;insetto e diventano fonte di cibo dei nematodi &#39;, consentendo loro di maturare e moltiplicarsi. Di solito, una o due generazioni di nematodi adulti sono prodotte all&#39;interno del cadavere insetto. La progenie degli ultimi riassocia generazione adulta con poche cellule batteriche in più specializzarsi modo che il loro precedente rapporto nutrizionale, e coltivare queste cellule nei loro intestini mentre si muovono fuori dalla carcassa insetti nel terreno dove potranno attendere un altro insetto di parassitare 6,11,14 (Figura 1). Sin dalla loro scoperta nel 1927, EPN sono stati considerati importanti alternative ai pesticidi chimici in quanto possono parassitare una vasta gamma di insetti che sono parassiti agricoli 3,4,5. Tuttavia, negli ultimi due decenni, questi nematodi e dei loro batteri simbionti sono stati riconosciuti come sistema modello malleabile per studiare aspetti biologici, ecologici ed evolutivi di ospite-microbo interactions 14. L&#39;obiettivo di questa presentazione è quello di mostrare i metodi e le tecniche più comunemente utilizzate per il campionamento del suolo e l&#39;isolamento di EPN. Una varietà di strumenti è disponibile e può essere utilizzato per raccogliere campioni di terreno, tra cui: defittonatrici suolo, cazzuole, trivelle, trivelle, tubi di campionamento, pale a mano, tra gli altri (Figura 2). A seconda dello scopo dello studio, due strategie di campionamento possono essere considerati: a) stratificato, b) campionamento casuale (Figura 3). Il campionamento stratificato è solitamente utilizzato come parte di uno studio intensivo in una zona specifica o demarked in un determinato periodo di tempo. In generale, un transetto è demarked e campioni di suolo sono presi a intervalli stabiliti nel transetto per un periodo di tempo (Figura 3A) 15. Il campionamento casuale viene generalmente impiegato quando concentrandosi su una vasta area. Questa strategia di campionamento è stato utilizzato per studiare la diversità di EPN fROM una vasta area geografica o regione (Figura 3B) 12. Una serie di fattori può essere considerato in funzione del focus dello studio tra cui una vasta gamma di altezze, texture del suolo e degli habitat (ad es., Campi coltivati, boschi, pascoli, parchi, spiagge, aree ripariali, ecc.) Mostriamo la tecnica dell&#39;insetto adescamento, che è stato originariamente descritto da biancheria da letto e Akhurst 1 e rappresenta un semplice e selettivo alternativa per il recupero EPN da campioni di suolo. Questa è una procedura selettiva che si basa sul presupposto che i nematodi (fase IJ) saranno attratti a un host insetto e parassitano esso. Questa tecnica può anche essere considerato per l&#39;isolamento di altri patogeni insetti quali funghi e batteri 8,10. Abbiamo anche dimostrare la tecnica trappola bianco modificato, che viene utilizzato per il recupero nematode progenie di insetti infetti padroni di casa 7,14. Si tratta di un sforzo incontratohod che offre il vantaggio di recuperare un &#39;clean&#39; nematode progenie priva di detriti dai cadaveri di insetti degradanti. Infine, le tecniche descritte ed illustrate in questo articolo corrispondono a quelli concepiti e / o eseguite nel nostro laboratorio così come quelli descritti da vari colleghi e collaboratori.

<table border="0" cellpadding="0" cellspacing="0" width="1119">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Name of Reagent/ Equipment</td>
			<td style="width:309px;">Company</td>
			<td style="width:241px;">Catalog Number</td>
			<td style="width:299px;">Comments/Description</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:271px;">Galleria mellonella</td>
			<td style="width:309px;">Timberline</td>
			<td style="width:241px;">http://www.timberlinefisheries.com/ProductDetails.asp?ProductCode=WAXLG</td>
			<td>for insect baiting technique</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:271px;">Filter Paper, 55mm Grade 1 Cellulose</td>
			<td style="width:309px;">Whatman/VWR</td>
			<td>28450-048</td>
			<td>infection chamber and White trap assembly</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">60 x 15 mm Petri Dishes</td>
			<td style="width:309px;">VWR</td>
			<td>25384-092</td>
			<td>infection chamber and White trap assembly</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">100 x 15 Petri Dishes</td>
			<td style="width:309px;">VWR</td>
			<td style="width:241px;">25384-088</td>
			<td>infection chamber and White trap assembly</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:271px;">ZIPloc Plastic Bags</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td style="width:241px;">N/A</td>
			<td>soil sampling</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:271px;">Mechanical Pipettor P1000, P200 ml</td>
			<td style="width:309px;">VWR</td>
			<td>89130-562; 89130-566&#160;</td>
			<td>infection chamber and White trap assembly</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">pippetor tips 1000ml, 200 ml</td>
			<td style="width:309px;">VWR</td>
			<td style="width:241px;">16466-004 ; 53510</td>
			<td>infection chamber and White trap assembly</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Bleach</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td>N/A</td>
			<td>soil sampling , desisnfecting</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Sodium Hypochlorite</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td>N/A</td>
			<td>soil sampling , desisnfecting</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">70% Ethyl alochol</td>
			<td style="width:309px;">AAPER</td>
			<td>17212945</td>
			<td>soil sampling , desisnfecting</td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;width:271px;">Shovels</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td style="width:241px;">N/A</td>
			<td>soil sampling</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Tubular soil sampler</td>
			<td>Accuproducts</td>
			<td style="width:241px;">N/A</td>
			<td>soil sampling</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Soil Probe, long handle</td>
			<td>Nupla&#160;</td>
			<td style="width:241px;">PRB4T 69401 Classic</td>
			<td>soil sampling</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:271px;">Measuring tape</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td style="width:241px;">N/A</td>
			<td>soil sampling</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">Flagging tape, various colors</td>
			<td style="width:309px;">Ace Hardware or local hardware store</td>
			<td style="width:241px;">N/A</td>
			<td>soil sampling</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">tissue culture flasks</td>
			<td style="width:309px;">VWR</td>
			<td style="width:241px;">Falcon, 29185-304&#160;</td>
			<td>White trap, collection of EPN</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:271px;">wash bottles, Polyethylene, Wide Mouth</td>
			<td style="width:309px;">VWR</td>
			<td>16650-107</td>
			<td>White trap, collection of EPN</td>
		</tr>
	</tbody>
</table>

soil sampling and isolation of entomopathogenic nematodes (steinernematidae, heterorhabditidae)

Nematodi entomopatogeni (aka EPN) rappresentano un gruppo di nematodi del suolo abitare che parassitano una vasta gamma di insetti. Questi nematodi appartengono a due famiglie: Steinernematidae e Heterorhabditidae. Fino ad oggi, più di 70 specie sono state descritte nel Steinernematidae e ci sono circa 20 specie in Heterorhabditidae. I nematodi hanno una collaborazione mutualistica con i batteri Enterobacteriaceae e insieme agiscono come un complesso potente insetticida che uccide una vasta gamma di specie di insetti. Qui, ci concentriamo sulle tecniche più comuni considerati per la raccolta EPN dal suolo. La seconda parte di questa presentazione si concentra sulla tecnica insetti adescamento, un approccio ampiamente utilizzato per l&#39;isolamento di EPN dai campioni di suolo, e la tecnica trappola bianco modificato che viene utilizzato per il recupero di questi nematodi da insetti infetti. Questi metodi e le tecniche sono passaggi fondamentali per la creazione di successo di culto EPNUres in laboratorio e anche la base per altri testi biologici che considerano questi nematodi come organismi modello per la ricerca in altre discipline biologiche. Le tecniche mostrate in questa presentazione corrispondono a quelle eseguite e / o creazione di membri della SP Archivio laboratorio così come quelli descritti da vari autori.

Soil Sample Collection Terza fase larve infettive di EPN sono le uniche fasi di vita liberi nel ciclo di vita di questi nematodi &#39;, che risiedono nel terreno (Figura 1). Pertanto, la raccolta di campioni di suolo è un metodo molto efficace per il recupero di questi nematodi. Figura 4 mostra un profilo del terreno che indica la profondità alla quale devono essere prelevati campioni. Preservare l&#39;umidità di un campione è un fattore chiave per la so...

Watch this Scientific Journal Video about Soil Sampling and Isolation of Entomopathogenic Nematodes Steinernematidae, Heterorhabditidae at JoVE.com

Soil Sampling and Isolation of Entomopathogenic Nematodes Steinernematidae, Heterorhabditidae

Nematodi entomopatogeni sono nematodi del suolo abitare che parassitano una vasta gamma di insetti. Dimostriamo metodi di campionamento utilizzati per l&#39;isolamento di questi nematodi dal terreno utilizzando due tecniche: l&#39;adescamento insetto e la trappola bianco modificato, per il recupero dei nematodi dai campioni di suolo e cadaveri insetti infetti, rispettivamente.

Campionamento e Isolamento di Nematodi entomopatogeni Suolo (Steinernematidae, Heterorhabditidae)

Entomopathogenic nematodes (a.k.a. EPN) represent a group of soil-inhabiting nematodes that parasitize a wide range of insects. These nematodes belong to ...

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Soil Sampling and Isolation of Entomopathogenic Nematodes (Steinernematidae, Heterorhabditidae)

24.7K Views.  University of Arizona.  Nematodi entomopatogeni sono nematodi del suolo abitare che parassitano una vasta gamma di insetti. Dimostriamo metodi di campionamento utilizzati per l'isolamento di questi nematodi dal terreno utilizzando due tecniche: l'adescamento insetto e la trappola bianco modificato, per il recupero dei nematodi dai campioni di suolo e cadaveri insetti infetti, rispettivamente. 

Video: Soil Sampling and Isolation of Entomopathogenic Nematodes Steinernematidae, Heterorhabditidae

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes and soil organic matter formation to small-scale stable-isotope biomarker probing. Coupling multiple stable isotopes such as 13C with 15N, 18O or&#160;2H has the potential to reveal even more information about complex stoichiometric relationships during biogeochemical transformations. Isotope labeled plant material has been used in various studies of litter decomposition and soil organic matter formation1-4. From these and other studies, however, it has become apparent that structural components of plant material behave differently than metabolic components (i.e. leachable low molecular weight compounds) in terms of microbial utilization and long-term carbon storage5-7. The ability to study structural and metabolic components separately provides a powerful new tool for advancing the forefront of ecosystem biogeochemical studies. Here we describe a method for producing 13C and 15N labeled plant material that is either uniformly labeled throughout the plant or differentially labeled in structural and metabolic plant components.
Here, we present the construction and operation of a continuous 13C and 15N labeling chamber that can be modified to meet various research needs. Uniformly labeled plant material is produced by continuous labeling from seedling to harvest, while differential labeling is achieved by removing the growing plants from the chamber weeks prior to harvest. Representative results from growing Andropogon gerardii Kaw demonstrate the system&#39;s ability to efficiently label plant material at the targeted levels. Through this method we have produced plant material with a 4.4 atom%13C and 6.7 atom%15N uniform plant label, or material that is differentially labeled by up to 1.29 atom%13C and 0.56 atom%15N in its metabolic and structural components (hot water extractable and hot water residual components, respectively). Challenges lie in maintaining proper temperature, humidity, CO2 concentration,&#160;and light levels in an airtight 13C-CO2 atmosphere for successful plant production. This chamber description represents a useful research tool to effectively produce uniformly or differentially multi-isotope labeled plant material for use in experiments on ecosystem biogeochemical cycling.

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

This method explains how to build and operate a continuous 13C and 15N isotope labeling chamber for uniform or differential plant tissue labeling. Representative results from metabolic and structural labeling of Andropogon gerardii are discussed.

Progettazione e funzionamento di un continuo<sup&gt; 13</sup&gt; C e<sup&gt; 15</sup&gt; N Etichettatura Camera di Uniform o differenziale, metaboliche e strutturali, Flora Isotope Labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes ...

Ricerca

Ambiente

Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals is often not well understood. Here we demonstrate an integrated field lysimetry and porewater sampling method for evaluating the mobility of chemicals applied to soils and established vegetation. Lysimeters, open columns made of metal or plastic, are driven into bareground or vegetated soils. Porewater samplers, which are commercially available and use vacuum to collect percolating soil water, are installed at predetermined depths within the lysimeters. At prearranged times following chemical application to experimental plots, porewater is collected, and lysimeters, containing soil and vegetation, are exhumed. By analyzing chemical concentrations in the lysimeter soil, vegetation, and porewater, downward leaching rates, soil retention capacities, and plant uptake for the chemical of interest may be quantified. Because field lysimetry and porewater sampling are conducted under natural environmental conditions and with minimal soil disturbance, derived results project real-case scenarios and provide valuable information for chemical management. As chemicals are increasingly applied to land worldwide, the described techniques may be utilized to determine whether applied chemicals pose adverse effects to human health or the environment.

Field lysimetry and porewater sampling allow researchers to evaluate the fate of chemicals applied to soils and established vegetation. The goal of this protocol is to demonstrate how to install required instrumentation and collect samples for chemical analysis during integrated field lysimetry and porewater sampling experiments.

Integrato Campo Lysimetry e Porewater campionamento per la valutazione della chimica Mobilità nel suolo e alla vegetazione Fondata

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals ...

An Optimized Enrichment Technique for the Isolation of Arthrobacter Bacteriophage Species from Soil Sample Isolates

Bacteriophage isolation from environmental samples has been performed for decades using principles set forth by pioneers in microbiology. The isolation of phages infecting Arthrobacter hosts has been limited, perhaps due to the low success rate of many previous isolation techniques, resulting in an underrepresented group of Arthrobacter phages available for study. The enrichment technique described here, unlike many others, uses a filtered extract free of contaminating bacteria as the base for indicator bacteria growth, Arthrobactersp. KY3901, specifically. By first removing soil bacteria the target phages are not hindered by competition with native soil bacteria present in initial soil samples. This enrichment method has resulted in dozens of unique phages from several different soil types and even produced different types of phages from the same enriched soil sample isolate. The use of this procedure can be expanded to most nutrient rich aerobic media for the isolation of phages in a vast diversity of interesting host bacteria.

An Optimized Enrichment Technique for the Isolation of Arthrobacter Bacteriophage Species from Soil Sample Isolates

We present an enrichment protocol for the isolation of bacteriophages infecting bacteria in the Arthrobacter genus. This enrichment protocol produces fast and reproducible results for the isolation and amplification of Arthrobacter phages from soil isolates.

Una tecnica di arricchimento Ottimizzato per l&#39;isolamento di<em&gt; Arthrobacter</em&gt; Batteriofago Specie campione di terreno Isolati

Bacteriophage isolation from environmental samples has been performed for decades using principles set forth by pioneers in microbiology. The isolation of ...

Assaying Predatory Feeding Behaviors in Pristionchus and Other Nematodes

This protocol provides multiple methods for the analysis and quantification of predatory feeding behaviors in nematodes. Many nematode species including Pristionchus pacificus display complex behaviors, the most striking of which is the predation of other nematode larvae. However, as these behaviors are absent in the model organism Caenorhabditis elegans, they have thus far only recently been described in detail along with the development of reliable behavioral assays 1. These predatory behaviors are dependent upon phenotypically plastic but fixed mouth morphs making the correct identification and categorization of these animals essential. In P. pacificus there are two mouth types, the stenostomatous and eurystomatous morphs 2, with only the wide mouthed eurystomatous containing an extra tooth and being capable of killing other nematode larvae. Through the isolation of an abundance of size matched prey larvae and subsequent exposure to predatory nematodes, assays including both "corpse assays" and "bite assays" on correctly identified mouth morph nematodes are possible. These assays provide a means to rapidly quantify predation success rates and provide a detailed behavioral analysis of individual nematodes engaged in predatory feeding activities. In addition, with the use of a high-speed camera, visualization of changes in pharyngeal activity including tooth and pumping dynamics are also possible.

Assaying Predatory Feeding Behaviors in Pristionchus and Other Nematodes

Behavioral assays provide powerful tools for understanding neuronal function. Here we present several protocols for quantifying predatory feeding behavior found in the model nematode Pristionchus pacificus and its relatives. Additionally, we provide methods for analyzing predatory feeding adaptations including mouth structures and teeth.

Saggio comportamenti alimentari predatori in<em&gt; Pristionchus</em&gt; E altri nematodi

This protocol provides multiple methods for the analysis and quantification of predatory feeding behaviors in nematodes. Many nematode species including ...

A Gusseted Thermogradient Table to Control Soil Temperatures for Evaluating Plant Growth and Monitoring Soil Processes

Thermogradient tables were first developed in the 1950s primarily to test seed germination over a range of temperatures simultaneously without using a series of incubators. A temperature gradient is passively established across the surface of the table between the heated and cooled ends and is lost quickly at distances above the surface. Since temperature is only controlled on the table surface, experiments are restricted to shallow containers, such as Petri dishes, placed on the table. Welding continuous aluminum vertical strips or gussets perpendicular to the surface of a table enables temperature control in depth via convective heat flow. Soil in the channels between gussets was maintained across a gradient of temperatures allowing a greater diversity of experimentation. The gusseted design was evaluated by germinating oat, lettuce, tomato, and melon seeds. Soil temperatures were monitored using individual, battery-powered dataloggers positioned across the table. LED lights installed in the lids or along the sides of the gradient table create a controlled temperature chamber where seedlings can be grown over a range of temperatures. The gusseted design enabled accurate determination of optimum temperatures for fastest germination rate and the highest percentage germination for each species. Germination information from gradient table experiments can help predict seed germination and seedling growth under the adverse soil conditions often encountered during field crop production. Temperature effects on seed germination, seedling growth, and soil ecology can be tested under controlled conditions in a laboratory using a gusseted thermogradient table.

Traditional thermogradient tables create a range of temperatures across the surface. Welding gussets perpendicular to the surface of a thermogradient table will control temperature in depth increasing possible research applications.

Una tabella soffietto Thermogradient di controllo della temperatura del suolo per la valutazione di crescita delle piante e monitoraggio processi del suolo

Thermogradient tables were first developed in the 1950s primarily to test seed germination over a range of temperatures simultaneously without using a ...

Measuring and Mapping Patterns of Soil Erosion and Deposition Related to Soil Carbonate Concentrations Under Agricultural Management

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonate (CaCO3) profiles. The objective is to describe a simple conceptual model and detailed protocol for repeatable field and laboratory measurements of these quantities. Here, accurate elevation is measured using a ground-based differential global positioning system (GPS); other data acquisition methods could be applied to the same basic method. Soil samples are collected from prescribed depth intervals and analyzed in the lab using an efficient and precise modified pressure-calcimeter method for quantitative analysis of inorganic carbon concentration. Standard statistical methods are applied to point data, and representative results show significant correlations between changes in soil surface layer CaCO3 and changes in elevation consistent with the conceptual model; CaCO3 generally decreased in depositional areas and increased in erosional areas. Maps are derived from point measurements of elevation and soil CaCO3 to aid analyses. A map of erosional and depositional patterns at the study site, a rain-fed winter wheat field cropped in alternating wheat-fallow strips, shows the interacting effects of water and wind erosion affected by management and topography. Alternative sampling methods and depth intervals are discussed and recommended for future work relating soil erosion and deposition to soil CaCO3.

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonates. Repeatable methods for field and laboratory measurements of these quantities and data analysis methods are described here.

Misura e mappatura modelli di erosione e deposizione relazionati al suolo carbonato concentrazioni sotto gestione agricola

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes ...

Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

Since the early 1960s, an alternative wastewater discharge practice at The Pennsylvania State University has been researched and its impacts monitored. Rather than discharging treated wastewater to a stream, and thereby directly impacting the stream quality, the effluent is applied to forested and cropped land managed by the University. Concerns related to reductions in soil hydraulic conductivity occur when considering wastewater reuse. The methodology described in this manuscript, matching soil sample size with the size of the laboratory-based hydraulic conductivity measurement apparatus, provides the benefits of a relatively rapid collection of samples with the benefits of controlled laboratory boundary conditions. The results suggest that there may have been some impact of wastewater reuse on the soil&#39;s ability to transmit water at deeper depths in the depressional areas of the site. Most of the reductions in the soil hydraulic conductivity in the depressions appear to be related to the depth from which the sample was collected, and by inference, associated with the soil structural and textural differences.

Here we present a methodology which matches a soil sample size and a hydraulic conductivity measurement device to prevent the so-called wall flow along the inside of the soil container from being erroneously included in water flow measurements. Its use is demonstrated with samples collected from a wastewater irrigation site.

Gli impatti di irrigazione delle acque reflue su conducibilità idraulica del suolo: accoppiata campo campionamento e determinazione in laboratorio della conducibilità idraulica satura

Since the early 1960s, an alternative wastewater discharge practice at The Pennsylvania State University has been researched and its impacts monitored. ...

Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The purpose of this manuscript is to provide detail on how to rapidly sample soil, rhizosphere, and endosphere of replicated field trials and analyze changes that may occur in the microbial communities due to sample type, treatment, and plant genotype. The experiment used to demonstrate these methods consists of replicated field plots containing two, pure, warm-season grasses (Panicum virgatum and Andropogon gerardii) and a low-diversity grass mixture (A. gerardii, Sorghastrum nutans, and Bouteloua curtipendula). Briefly, plants are excavated, a variety of roots are cut and placed in phosphate buffer, and then shaken to collect the rhizosphere. Roots are brought to the laboratory on ice and surface sterilized with bleach and ethanol (EtOH). The rhizosphere is filtered and concentrated by centrifugation. Excavated soil from around the root ball is placed into plastic bags and brought to the lab where a small amount of soil is taken for DNA extractions. DNA is extracted from roots, soil, and rhizosphere and then amplified with primers for the V4 region of the 16S rRNA gene. Amplicons are sequenced, then analyzed with open access bioinformatics tools. These methods allow researchers to test how the microbial community diversity and composition varies due to sample type, treatment, and plant genotype. Using these methods along with statistical models, the representative results demonstrate there are significant differences in microbial communities of roots, rhizosphere, and soil. Methods presented here provide a complete set of steps for how to collect field samples, isolate, extract, quantify, amplify, and sequence DNA, and analyze microbial community diversity and composition in replicated field trials.

Excavation of plant roots from the field as well as processing of samples into endosphere, rhizosphere, and soil are described in detail, including DNA extraction and data analysis methods. This paper is designed to enable other laboratories to use these techniques for the study of soil, endosphere, and rhizosphere microbiomes.

Isolamento ed analisi di comunità microbiche nel suolo, rizosfera e radici negli esperimenti di erba perenne

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The ...

Use of Principal Components for Scaling Up Topographic Models to Map Soil Redistribution and Soil Organic Carbon

Landscape topography is a critical factor affecting soil formation and plays an important role in determining soil properties on the earth surface, as it regulates the gravity-driven soil movement induced by runoff and tillage activities. The recent application of Light Detection and Ranging (LiDAR) data holds promise for generating high spatial resolution topographic metrics that can be used to investigate soil property variability. In this study, fifteen topographic metrics derived from LiDAR data were used to investigate topographic impacts on redistribution of soil and spatial distribution of soil organic carbon (SOC). Specifically, we explored the use of topographic principal components (TPCs) for characterizing topography metrics and stepwise principal component regression (SPCR) to develop topography-based soil erosion and SOC models at site and watershed scales. Performance of SPCR models was evaluated against stepwise ordinary least square regression (SOLSR) models. Results showed that SPCR models outperformed SOLSR models in predicting soil redistribution rates and SOC density at different spatial scales. Use of TPCs removes potential collinearity between individual input variables, and dimensionality reduction by principal component analysis (PCA) diminishes the risk of overfitting the prediction models. This study proposes a new approach for modeling soil redistribution across various spatial scales. For one application, access to private lands is often limited, and the need to extrapolate findings from representative study sites to larger settings that include private lands can be important.

Landscape processes are critical components of soil formation and play important roles in determining soil properties and spatial structure in landscapes. We propose a new approach using stepwise principal component regression to predict soil redistribution and soil organic carbon across various spatial scales.

Utilizzo di componenti Principal per Scaling Up modelli topografici per mappare la ridistribuzione del suolo e del suolo di carbonio organico

Landscape topography is a critical factor affecting soil formation and plays an important role in determining soil properties on the earth surface, as it ...

Estimation of Crystalline Cellulose Content of Plant Biomass using the Updegraff Method

Cellulose is the most abundant polymer on Earth generated by photosynthesis and the main load-bearing component of cell walls. The cell wall plays a significant role in plant growth and development by providing strength, rigidity, rate and direction of cell growth, cell shape maintenance, and protection from biotic and abiotic stressors. The cell wall is primarily composed of cellulose, lignin, hemicellulose and pectin. Recently plant cell walls have been targeted for the second-generation biofuel and bioenergy production. Specifically, the cellulose component of the plant cell wall is used for the production of cellulosic ethanol. Estimation of cellulose content of biomass is critical for fundamental and applied cell wall research. The Updegraff method is simple, robust, and the most widely used method for the estimation of crystalline cellulose content of plant biomass. The alcohol insoluble crude cell wall fraction upon treatment with Updegraff reagent eliminates the hemicellulose and lignin fractions. Later, the Updegraff reagent resistant cellulose fraction is subjected to sulfuric acid treatment to hydrolyze the cellulose homopolymer into monomeric glucose units. A regression line is developed using various concentrations of glucose and used to estimate the amount of the glucose released upon cellulose hydrolysis in the experimental samples. Finally, the cellulose content is estimated based on the amount of glucose monomers by colorimetric anthrone assay.

The Updegraff method is the most widely used method for the cellulose estimation. The main purpose of this demonstration is to provide a detailed Updegraff protocol for estimation of cellulose content in plant biomass samples.

Stima del contenuto cristallino di cellulosa della biomassa vegetale utilizzando il metodo Updegraff

Cellulose is the most abundant polymer on Earth generated by photosynthesis and the main load-bearing component of cell walls. The cell wall plays a ...