Response of vegetable pads of two cactus cultivars to ...

Response of vegetable pads of two cactus cultivars to the presence of Salmonella strains ǤǤ †‡ Žƒ ‹˜ƒǦƵ Ž˜ƒ”‡œͳǡ ǤǤ ‡”ƒƴ †‡œǦ‰—‹ƒ‘ͳǡƒǡ ǤǤƒ˜ƒŽ‡–ƒǦƒ…‡”ƒ͵ǡǤ‘–‘Ǧ‡”ƒƴ †‡œ͵ƒ† Ǥƒ–‡ŽͶ

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‘””ƒŽ‡•Ǧ ƒ”…Çƴƒʹǡ

ͳ‘•–‰”ƒ†‘

‡ ‹–‘•ƒ‹†ƒ†Ǧ ‹–‘’ƒ–‘Ž‘‰Çƴƒ ‘Ž‡‰‹‘ †‡ ‘•–‰”ƒ†—ƒ†‘•ǡ ‘–‡…‹ŽŽ‘ǡ †‘ †‡ ‡š‹…‘ǡ ‡š‹…‘Ǣ †‡ †—•–”‹ƒ• ‰”Çƴ…‘Žƒ•ǡ ‹˜Ǥ —–‘ƴ ‘ƒ Šƒ’‹‰‘ǡ †‘ †‡ ‡š‹…‘ǡ ‡š‹…‘Ǣ ͵‘•–‰”ƒ†‘ ‡ ‘–ƒƴ ‹…ƒǡ ‘Ž‡‰‹‘ †‡ ‘•–‰”ƒ†—ƒ†‘•Ǧ‘–‡…‹ŽŽ‘ǡ †‘ †‡ ‡š‹…‘ǡ ‡š‹…‘Ǣ Ͷ ‡’ƒ”–‡– ‘ˆ ‰”‹…—Ž–—”‡ǡ ‰”‹…—Ž–—”ƒŽ‡•‡ƒ”…Š‡”˜‹…‡ǡ‡Ž–•˜‹ŽŽ‡ǡǡǤ ʹ‡’ƒ”–ƒ‡–‘

Abstract Tender cactus pads (cladodes) or nopalitos (Opuntia ficusǦindica) are an important vegetable in Mexico. They are often preǦtrimmed, cut and packaged, and whileusuallyconsumedcooked,theymayalsobeeatenrawinsalads.Salmonellaisan enteropathogenic bacterium that can adapt to adverse environmental conditions. Although it has been reported that SalmonellaǦinfected plants are asymptomatic, wilting, yellowing, biomass loss and a hypersensitive response (HR) have been demonstrated in plant tissues. The aim of this study was to investigate plant tissue responsetodifferentstrainsofSalmonellaentericaintwocultivarsofcactusaswellas the persistence of Salmonella strains in the tissue. The top of pads (20Ǧ25 cm) of greenhouseǦgrown (20°C, 51.2% RH) ‘Milpa Alta’ and ‘Atlixco’ cultivars were inoculatedwithwater(control)or1mL8.0logCFUofstrainsSalmonellatyphimurium (N4), Salmonella javiana (N7) isolated from nopalitos, and laboratory strain S.typhimurium ATCC 23564 (Sal 4). Cladodes (n=20) from each cactus cultivar were sampledandevaluatedevery24hfor4daysstarting6hafterinoculationforvisual symptoms,colorchangeandSalmonellapersistenceinthetissue.Dataweresubjected toanalysisofvariancewithmeanseparationbyTtest(Ƚ=0.05).Colorandappearance changedinlongitudinalsectionsofpadsofbothcultivarsonlyintheareawherethe bacteriawereinfiltratedandthiscouldbeconsideredtobeahypersensitiveresponse. AllthreeSalmonellastrainspersisted48horlonger. Keywords: Opuntia ficusǦindicaǡ ‘’ƒŽ‹–‘•ǡ Salmonella entericaǡ Salmonella typhimuriumǡ Salmonellajaviana INTRODUCTION ‡†‡” …ƒ…–—• ’ƒ†• ȋ…Žƒ†‘†‡•Ȍ ‘” Ǯ‘’ƒŽ‹–‘•ǯ ƒ”‡ ƒ ‹’‘”–ƒ– ƒ† –”ƒ†‹–‹‘ƒŽ ˜‡‰‡–ƒ„Ž‡‹‡š‹…‘ƒ†ƒ•’‡…‹ƒŽ–›˜‡‰‡–ƒ„Ž‡‹ƒ†‡Ž•‡™Š‡”‡ǤŠ‡›ƒ”‡‘ˆ–‡…—–ƒ† ’ƒ…ƒ‰‡†ǡ ƒ† ™Š‹Ž‡ —•—ƒŽŽ› …‘•—‡† …‘‘‡†ǡ –Š‡› ƒ› ƒŽ•‘ „‡ ‡ƒ–‡ ‹ •ƒŽƒ†•Ǥ ‘‡ ’Žƒ–• †‡˜‡Ž‘’ •›’–‘• •—…Š ƒ• ™‹Ž–‹‰ǡ ›‡ŽŽ‘™‹‰ ƒ† Ž‘•• ‘ˆ „‹‘ƒ•• ‹ ”‡•’‘•‡ –‘ ‡–‡”‘’ƒ–Š‘‰‡‹… „ƒ…–‡”‹ƒ ȋ…Š‹‘”ƒ ‡– ƒŽǤǡ ʹͲͲͺȌǤ Ǯ‹Ž’ƒ Ž–ƒǯ ’ƒ†• ‹ ’Žƒ– ”‡…‘”†‡† †ƒ”‡‹‰ƒ†”‡†—…–‹‘‹„ƒ…–‡”‹ƒŽ’‘’—Žƒ–‹‘†—”‹‰–Š‡ˆ‹”•–ͶͺŠƒˆ–‡”‹ˆ‹Ž–”ƒ–‹‘™‹–Š Salmonellaȋƒ†ƒƒŽ‰ƒ†‘‡–ƒŽǤǡʹͲͳ͵ȌǤŠ‡•’‡‡†ƒ†”‡•’‘•‡…Šƒ”ƒ…–‡”‹•–‹…•ǡƒ•™‡ŽŽƒ• –Š‡ †‡Ž‹‡ƒ–‹‘ ‘ˆ –Š‡ Ž‡•‹‘ •‹–‡ ‘ˆ ‹‘…—Žƒ–‹‘ ”ƒ‹•‡† –Š‡ Š›’‘–Š‡•‹• –Šƒ– Salmonella ƒ…–‹˜ƒ–‡••‹‰ƒŽ•–Šƒ–‹†—…‡ƒŠ›’‡”•‡•‹–‹˜‡”‡•’‘•‡ȋȌ‹‘’ƒŽ’Žƒ–•ȋ…Š‹‘”ƒ‡–ƒŽǤǡ ʹͲͲͺȌǤ Š‡”‡ˆ‘”‡ǡ–Š‹••–—†›ƒ‹‡†–‘ǣͳȌ”‡…‘”†…Šƒ‰‡•‹–‹••—‡…‘Ž‘”ƒ–‹‘ƒ†ƒ’’‡ƒ”ƒ…‡ †—‡–‘†‹ˆˆ‡”‡–•–”ƒ‹•‘ˆSalmonellaentericaǢʹȌ…‘’ƒ”‡–Š‡”‡•’‘•‡„‡–™‡‡…—Ž–‹˜ƒ”•‘ˆ …ƒ…–—•Ǣ ƒ†ǡ ͵Ȍ –‡•– –Š‡ ƒ„‹Ž‹–› ‘ˆ Salmonella •–”ƒ‹• –‘ ’‡”•‹•– ‹–‘ –Š‡ –‹••—‡Ǥ • •—…Šǡ ‘—” Š›’‘–Š‡•‡•™‡”‡ƒ•ˆ‘ŽŽ‘™•ǣ ͳȌ Š‡…Šƒ‰‡‹–‹••—‡…‘Ž‘”ƒ–‹‘‹”‡•’‘•‡–‘Salmonella•–”ƒ‹•‹••‹‹Žƒ”„‡–™‡‡ 

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ͲŵĂŝů͗ĂŚĞƌŶĂŶĚĞnjΛĐŽůƉŽƐ͘ŵdž

 

ĐƚĂ,ŽƌƚŝĐ͘ϭϭϰϭ͘/^,^ϮϬϭϲ͘K/ϭϬ͘ϭϳϲϲϬͬĐƚĂ,ŽƌƚŝĐ͘ϮϬϭϲ͘ϭϭϰϭ͘Ϯϰ WƌŽĐ͘////Ŷƚ͘ŽŶĨ͘ŽŶ&ƌĞƐŚͲƵƚWƌŽĚƵĐĞ͗DĂŝŶƚĂŝŶŝŶŐYƵĂůŝƚLJĂŶĚ^ĂĨĞƚLJ Ě͗͘D͘/͘ĂŶƚǁĞůů

ϮϬϳ

‘’ƒŽ…—Ž–‹˜ƒ”•ǡƒ† ʹȌ Salmonella•–”ƒ‹•Šƒ˜‡–Š‡ƒ„‹Ž‹–›–‘’‡”•‹•–‹–‘–Š‡‘’ƒŽ…—Ž–‹˜ƒ”•ǯ–‹••—‡Ǥ Š‹••–—†›…‘–”‹„—–‡•–‘–Š‡‘™Ž‡†‰‡‘ˆ‘‡‘ˆ–Š‡…ŠƒŽŽ‡‰‡•ˆƒ…‹‰–Š‡ˆ”‡•Š…—– ƒ”‡ƒǣ™Š‡–Š‡”•‘‡’Žƒ–…—Ž–‹˜ƒ”•ƒ”‡‘”‡”‡•‹•–ƒ––‘Š—ƒ’ƒ–Š‘‰‡•–Šƒ‘–Š‡”•ǤŠ‡ ‹…”‡ƒ•‡ ‹ ’‡” …ƒ’‹–ƒ …‘•—’–‹‘ ‘ˆ ”ƒ™ ‘” ‹‹ƒŽŽ› ’”‘…‡••‡† ˆ”—‹– ƒ† ˜‡‰‡–ƒ„Ž‡• ‹• ƒ‘‰–Š‡ƒ‹ˆƒ…–‘”•…‘–”‹„—–‹‰–‘‘—–„”‡ƒ•‘ˆŠ—ƒ‹ˆ‡…–‹‘•Ǥ MATERIALSANDMETHODS Plantmaterial Š‡ ‡š’‡”‹‡– ™ƒ• …ƒ””‹‡† ‘—– ‘ …ƒ…–—• ȋOpuntia ficusǦindica ǤȌ …—Ž–‹˜ƒ”• Ǯ‹Ž’ƒ Ž–ƒǯ ƒ† Ǯ–Ž‹š…‘ǯǡ ‰”‘™ ‹ ’‘Ž›‡–Š›Ž‡‡ ’‘–• ™‹–Š ƒ ‹š–—”‡ ‘ˆ ‰”‘—†Ǧ˜‡”‹…‘’‘•– ȋ͵ǤͷǣͳǤͷȌ™‹–Šƒ•ƒ†›ǦŽ‘ƒ–‡š–—”‡ȋ•ƒ†͸ʹΨǡ•‹Ž–͵ͳǤ͵Ψƒ†…Žƒ›͸Ǥ͹ΨȌ‹ƒ‰”‡‡Š‘—•‡ƒ– ͳ͹Ǥ͵ιȋ–‡’”ƒ‰‡ͳ͵Ǥ͵ǦʹʹǤͻιȌƒ†ͷͳǤʹΨȋ”ƒ‰‡͵ͺǤͳǦͳͲͲΨȌǡ†—”‹‰™‹–‡”ʹͲͳͶǤ Bacterialstrains ‹Ž†Ǧ–›’‡„ƒ…–‡”‹ƒŽ…‡ŽŽ•‘ˆSalmonellatyphimuriumȋͶȌƒ†S.javianaȋ͹Ȍǡ‹•‘Žƒ–‡† ˆ”‘…ƒ…–—•’ƒ†•ǡƒ†Žƒ„‘”ƒ–‘”›•–”ƒ‹S.typhimuriumʹ͵ͷ͸ͶȋƒŽͶȌ’”‘˜‹†‡†„›–Š‡ ‡–”‘ †‡ ˜‡•–‹‰ƒ…‹‘ƴ  ‡ Ž‹‡–ƒ…‹‘ƴ  › ‡•ƒ””‘ŽŽ‘ Ǥ Ǥ ™‡”‡ ƒ†‡ ”‡•‹•–ƒ– –‘ ƒƒ›…‹„›•’‘–ƒ‡‘—•—–ƒ–‹‘ǤŠ‡•‡•–”ƒ‹•™‡”‡‰”‘™‹–”›’–‘‡•‘›ƒ‰ƒ”ȋȌ ƒ–͵͹ιˆ‘”ͶͺŠˆ‘”’Žƒ–‹‘…—Žƒ–‹‘Ǥ ”‘œ‡•–‘……—Ž–—”‡•™‡”‡•–”‡ƒ‡†‘–”›’–‘‡•‘› „”‘–Š ‡†‹— ˆ‘” ƒ ‘˜‡”‹‰Š– ‹…—„ƒ–‹‘ ƒ† –Š‡ ‹–‘  ˆ‘” •—„•‡“—‡– ‹‘…—Ž— ’”‡’ƒ”ƒ–‹‘Ǥ ‡†‹— ™ƒ• •—’’Ž‡‡–‡† ™‹–Š ƒƒ›…‹ ȋǡ ͷͲ ρ‰ ǦͳȌ ˆ‘” •‡Ž‡…–‹˜‡ ‡—‡”ƒ–‹‘‘ˆǦ”‡•‹•–ƒ–Ͷǡ͹ƒ†ƒŽͶ•–”ƒ‹•Ǥ Plantinoculation ƒ…–‡”‹ƒŽ …‡ŽŽ• ™‡”‡ …‘ŽŽ‡…–‡† „› Ž‘‘’ ˆ”‘ ƒ ͶͺǦŠǦ‘Ž† …—Ž–—”‡ ƒ† –”ƒ•ˆ‡””‡† ‹–‘ ƒ –—„‡…‘–ƒ‹‹‰•–‡”‹Ž‡†‹•–‹ŽŽ‡†™ƒ–‡”—–‹Žƒ‘’–‹…ƒŽ†‡•‹–›ȋͷ͸Ͳ Ȍ‘ˆͲǤͷ™ƒ•”‡ƒ…Š‡† –‘ ‰‡– ͺ Ž‘‰   ǦͳǤ ‡  ‘ˆ „ƒ…–‡”‹ƒŽ •—•’‡•‹‘ ‘” ™ƒ–‡” ™ƒ• ‹ˆ‹Ž–”ƒ–‡† ƒ– –Š‡ –‘’ ƒ”‰‹‘ˆƒ…Žƒ†‘†‡ȋʹͲǦʹͷ…Ž‘‰ȌǤŠ‡”‡™‡”‡ʹͲ…Žƒ†‘†‡•’‡”…ƒ…–—•…—Ž–‹˜ƒ”‡˜ƒŽ—ƒ–‡† ‡˜‡”›ʹͶŠˆ‘”Ͷ†•–ƒ”–‹‰͸Šƒˆ–‡”‹‘…—Žƒ–‹‘ˆ‘”˜‹•—ƒŽ•›’–‘•ǡ…‘Ž‘”‡ƒ•—”‡‡–ƒ† ’‡”•‹•–‡…‡ ‹ –Š‡ –‹••—‡ ƒ……‘”†‹‰ –‘ ”‘›‡…–‘ ǦͳͲͻǦͳǦͳͻͻͶ ȋ‘Ǥǡ ͳͻͻͶȌ ƒ† ƒ†‹‰ƒ‡–ƒŽǤȋʹͲͲͳȌǤ Colormeasurement –‡”ƒŽ –‹••—‡ …‘Ž‘” ȋ‡…”‘•‹•Ȍ ƒ† ƒ’’‡ƒ”ƒ…‡ ‘ –Š‡ …Žƒ†‘†‡ ‹ˆ‹Ž–”ƒ–‹‘ •‹–‡ ™‡”‡ ”‡‰‹•–‡”‡†ƒ†‡ƒ•—”‡†™‹–Šƒ‹‹…ƒ…‘Ž‘”‹‡–‡”ȋŽ—•ǡ‘ǤͶͷȀǦȌ—•‹‰–Š‡ȗǡƒȗ ƒ† „ȗ …‘Ž‘” …Žƒ••‹ˆ‹…ƒ–‹‘ •›•–‡ ȋ… —‹”‡ǡ ͳͻͻʹȌǤ ™‘ …‘Ž‘” ‡ƒ•—”‡‡–• ’‡” …Žƒ†‘†‡ ™‡”‡–ƒ‡Ǥ Bacterialanalysis ‘…—Žƒ–‡† ‘’ƒŽ …Žƒ†‘†‡• ™‡”‡ Šƒ”˜‡•–‡† ƒ•‡’–‹…ƒŽŽ› „› …—––‹‰ –Š‡ …Žƒ†‘†‡ ™‹–Š ƒ •–‡”‹Ž‡ ‹ˆ‡ ƒ– –Š‡ –”ƒ•‹–‹‘ ’‘‹– „‡–™‡‡ –Š‡ ‹‡†‹ƒ–‡ „‡Ž‘™ …Žƒ†‘†‡Ǥ Žƒ†‘†‡• ™‡”‡ –”ƒ•’‘”–‡†–‘–Š‡Žƒ„‘”ƒ–‘”›‹•–‡”‹Ž‡ƒŽ—‹—ˆ‘‹Žƒ†‡’–‹ƒ…‘–ƒ‹‡”Ž‹‡†™‹–Š‹…‡ –‘„‡ƒƒŽ›œ‡†™‹–Š‹–Š‡ͶŠˆ‘ŽŽ‘™‹‰Šƒ”˜‡•–Ǥ ƒ…Š …Žƒ†‘†‡ ™ƒ• ™ƒ•Š‡† ™‹–Š •–‡”‹Ž‡ –ƒ’ ™ƒ–‡” –‘ ”‡‘˜‡ Ž‘‘•‡Ž› ƒ––ƒ…Š‡† •—”ˆƒ…‡ „ƒ…–‡”‹ƒǤ•‡…–‹‘ȋͶǤͷ…†‹ƒ‡–‡”Ȍ‘ˆ–Š‡‹ˆ‹Ž–”ƒ–‡†–‹••—‡™ƒ•’Žƒ…‡†‹ƒ•–‘ƒ…Š‡”„ƒ‰ …‘–ƒ‹‹‰ ͶͲǤͷ  ‘ˆ ͲǤͳΨ •–‡”‹Ž‡ ’‡’–‘‡ ™ƒ–‡” ƒ† –Š‡ ƒ…‡”ƒ–‡† ‹ ƒ –‘ƒ…Š‡” ȋͶͲͲ…‹”…—Žƒ–‘”Ȍƒ–͵ͲͲ•–”‘‡•‹Ǧͳˆ‘”ͳʹͲ•ǤSalmonella…‡ŽŽ•™‡”‡†‡–‡”‹‡† „› ’Žƒ–‹‰ •‡”‹ƒŽ †‹Ž—–‹‘• ‘–‘ ‡–‘‡ ‡†‹— •—’’Ž‡‡–‡† ™‹–Š ͷͲ ‰  ǦͳǤ Žƒ–‡• ™‡”‡‹…—„ƒ–‡†ƒ–͵͹ιˆ‘”ͶͺŠ„‡ˆ‘”‡‡šƒ‹ƒ–‹‘ˆ‘”’”‡•—’–‹˜‡…‘Ž‘‹‡•‘ˆSalmonellaǤ Statisticalanalysis ƒ–ƒ™‡”‡•—„Œ‡…–‡†–‘ƒƒŽ›•‹•‘ˆ˜ƒ”‹ƒ…‡™‹–Š‡ƒ•‡’ƒ”ƒ–‹‘„›–‡•–ȋȽαͲǤͲͷȌǤ Š‡ ‡ˆˆ‡…– ‘ˆ •–”ƒ‹ǡ …ƒ…–—• …—Ž–‹˜ƒ”ǡ ƒ† ‹…—„ƒ–‹‘ ’‡”‹‘† ‘ Salmonella ’‡”•‹•–‡…‡ ™ƒ• ϮϬϴ

ƒƒŽ›œ‡†ǤŠ‡”‡•—Ž–•™‡”‡…‘•‹†‡”‡†•–ƒ–‹•–‹…ƒŽŽ›•‹‰‹ˆ‹…ƒ–ƒ–PδͲǤͲͷǤ RESULTSANDDISCUSSION Colorchanges ‹••—‡…‘Ž‘”ƒ†ƒ’’‡ƒ”ƒ…‡…Šƒ‰‡†‘’ƒ†•‘ˆ„‘–Š…ƒ…–—•…—Ž–‹˜ƒ”•„—–‘Ž›‹–Š‡ ƒ”‡ƒ™Š‡”‡–Š‡„ƒ…–‡”‹ƒ™‡”‡‹ˆ‹Ž–”ƒ–‡†ǤŽ–Š‘—‰Š–Š‡ƒˆˆ‡…–‡†ƒ”‡ƒ••–ƒ”–‡†–‘•Š‘™–Š‡ˆ‹”•– •‹‰•‘ˆ‡…”‘•‹•ƒˆ–‡”–Š‡‹ˆ‹Ž–”ƒ–‹‘‘ˆͶƒ†͹ǡ‘…Šƒ”ƒ…–‡”‹•–‹…†‹ˆˆ‡”‡…‡•™‡”‡ˆ‘—† „‡–™‡‡•›’–‘•‹†—…‡†„›Salmonella•–”ƒ‹•Ǥ‹–Š–Š‡‡š…‡’–‹‘‘ˆƒ͹ʹŠǮ‹Ž’ƒŽ–ƒǯ ’ƒ†ǡ‘’ƒ†•‹ˆ‹Ž–”ƒ–‡†™‹–Š™ƒ–‡”†‡˜‡Ž‘’‡†‡…”‘•‹•ȋ ‹‰—”‡ͳȌǤ ”‘ƒ͹ʹŠǮ‹Ž’ƒŽ–ƒǯ ’ƒ†ǡ‘Salmonella…‡ŽŽ•™‡”‡”‡…‘˜‡”‡†‘‡–‘‡•—’’Ž‡‡–‡†‡†‹—Ǥ

 ‹‰—”‡ͳǤ –‡”ƒŽŽ‘‰‹–—†‹ƒŽ•‡…–‹‘•‘ˆ…ƒ…–—•’ƒ†•ƒˆ–‡”‹ˆ‹Ž–”ƒ–‹‘™‹–Š™ƒ–‡”ȋ‘–”‘ŽȌ ‘” Salmonella …‡ŽŽ• ȋƒŽͶǡ Ͷ ƒ† ͹ȌǤ Š‡ ƒ””‘™• •Š‘™ –Š‡ †ƒ” Ž‡•‹‘• ȋ‡…”‘•‹•Ȍ†‡˜‡Ž‘’‡†‘’ƒ†•ƒˆ–‡”‹‘…—Žƒ–‹‘Ǥ ‘–Š …—Ž–‹˜ƒ”• ’”‡•‡–‡† …Šƒ‰‡• ‹ ‹–‡”ƒŽ …‘Ž‘” ‹ –‹••—‡ ‹ˆ‹Ž–”ƒ–‡† ™‹–Š „ƒ…–‡”‹ƒǤ Š‡ȗ˜ƒŽ—‡•ˆ‘”–Š‡–™‘‘’ƒŽ…—Ž–‹˜ƒ”•™‹–Šƒ†™‹–Š‘—–„ƒ…–‡”‹ƒ™‡”‡•‹‹Žƒ”Ǥ …‘–”ƒ•–ǡ ƒȗ ˜ƒŽ—‡• ™‡”‡ †‹ˆˆ‡”‡– „‡–™‡‡ ’ƒ†• ™Š‡”‡ ƒ ‹…”‡ƒ•‡ ™ƒ• ‘„•‡”˜‡† ‹ ’ƒ†• ‹ˆ‹Ž–”ƒ–‡† ™‹–ŠͶǡ͹ƒ†ƒŽͶȋ ‹‰—”‡ʹȌǤ‡ƒ”Ž›‹…”‡ƒ•‡‹ƒȗ‹†‹…ƒ–‡††‡˜‡Ž‘’‡–‘ˆ‡…”‘•‹•ǡ •—‰‰‡•–‹‰ƒSalmonellaǦ‹†—…‡†”‡•’‘•‡‹–Š‡…ƒ…–—•’ƒ†•Ǥ



 

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 ‹‰—”‡ʹǤ ‘Ž‘” …Šƒ‰‡• ȋȗ ƒ† ƒȗ ˜ƒŽ—‡•Ȍ ‹ ‹–‡”ƒŽ Ž‘‰‹–—†‹ƒŽ •‡…–‹‘• ‘ˆ …ƒ…–—• ’ƒ†• ƒˆ–‡” ‹ˆ‹Ž–”ƒ–‹‘ ™‹–Š ™ƒ–‡” ȋ‘–”‘Žǡ †ƒ•Š‡† Ž‹‡Ȍ ‘” Salmonella …‡ŽŽ• ȋƒŽͶǡ Ͷ ƒ†͹ȌǤƒ–ƒƒ”‡‡ƒ•‘ˆ–™‘”‡’Ž‹…ƒ–‡•άȋPζͲǤͲͷȌǤ PersistenceofSalmonella ƒ’‹† –‹••—‡ …‘Ž‘” …Šƒ‰‡ ‘ˆ …ƒ…–—• ’ƒ†• …‘—Ž† „‡ ƒ••‘…‹ƒ–‡† ™‹–Š ‹Š‹„‹–‹‘ ‘ˆ Salmonella‹„‘–Š‘’ƒŽ…—Ž–‹˜ƒ”•ǤŠ‡—„‡”‘ˆŽ‹˜‹‰Salmonella…‡ŽŽ•‹ˆ‹Ž–”ƒ–‡†‹–‘–Š‡ …ƒ…–—• –‹••—‡ †‡…”‡ƒ•‡† ”ƒ’‹†Ž› †—”‹‰ –Š‡ ˆ‹”•– Ͷͺ ŠǤ Š‡”‡ ™‡”‡ •–ƒ–‹•–‹…ƒŽ †‹ˆˆ‡”‡…‡• ‹ Salmonella’‡”•‹•–‡…‡„‡–™‡‡‘’ƒŽ…—Ž–‹˜ƒ”•Ǣ†—”‹‰–Š‡ˆ‹”•–ͶͺŠ‘—”•–Š‡’‡”•‹•–‡…‡‘ˆ –Š‡„ƒ…–‡”‹ƒŽ•–”ƒ‹•™ƒ••‹‰‹ˆ‹…ƒ–Ž›Ž‘™‡”‹Ǯ‹Ž’ƒŽ–ƒǯ–Šƒ‹Ǯ–Ž‹š…‘ǯȋƒ„Ž‡•ͳƒ†ʹȌǤ ‘™‡˜‡”ǡ†‹ˆˆ‡”‡…‡•‹’‡”•‹•–‡…‡†—‡–‘Salmonella•–”ƒ‹•™‡”‡‘–•‹‰‹ˆ‹…ƒ–ǤŠ‡”ƒ’‹† …‘Ž‘”…Šƒ‰‡‘ˆ–Š‡–‹••—‡ƒ†‡ƒ”Ž›†‡…”‡ƒ•‡‹•–”ƒ‹’‘’—Žƒ–‹‘•—‰‰‡•–‡†ƒŠ›’‡”•‡•‹–‹˜‡ ”‡•’‘•‡‹‘’ƒŽ–‘Salmonellaƒ……‘”†‹‰–‘…Š‹‘”ƒ‡–ƒŽǤȋʹͲͳͳȌǤ ƒ„Ž‡ͳǤ ‡”•‹•–‡…‡‘ˆSalmonella‹…ƒ…–—•’ƒ†•Ǥ Log CFU g-1 fresh tissue Treatment Control Sal4 N4 N7

6 h 0.0 7.7* 7.7* 8.4*

24 h 0.0 6.2* 5.6* 3.5*

Atlixco 48 h 0.0 3.3* 4.3* 1.3*

72 h 0.0 1.7 0.1 1.7

96 h 0.0 0.8* 0.5 0.8

6h 0.0 5.9 6.1 6.6

24 h 0.0 3.0 2.6 1.2

Milpa Alta 48 h 0.0 1.0 0.8 2.1

*Data in the same column of ‘Atlixco’ are statistically different (P”0.05) from their counterparts in ‘Milpa Alta’.

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72 h 0.0 1.2 0.0 1.2

96 h 0.0 0.3 0.0 1.1

ƒ„Ž‡ʹǤ ˜‡”ƒ‰‡˜ƒŽ—‡•ƒ†‡ƒ…‘’ƒ”‹•‘‘ˆSalmonella’‡”•‹•–‡…‡‹…ƒ…–—•’ƒ†•Ǥ Time after infiltration (h) 6 24 48 72 96 HSD1 1T

Log CFU g-1 fresh tissue Milpa Alta Atlixco 6.0 a 8.1 a 2.9 b 4.9 b 2.0 bc 3.1 c 2.0 bc 1.9 cd 1.5 c 1.5 d 1.3 1.3

test (P=0.05).

Numbers in the same column with the same letters are not statistically different (Pİ0.05).

Salmonella ‹• ƒ Š—ƒ ’ƒ–Š‘‰‡ –Šƒ– Šƒ• „‡‡ ”‡’‘”–‡† –‘ …‘–ƒ‹ƒ–‡ ”ƒ™ …ƒ…–—• ’ƒ†•‘”‘’ƒŽȋ‡”ƒƴ †‡œǦ‰—‹ƒ‘‡–ƒŽǤǡʹͲͲͻȌƒ†‹†—…‡’Žƒ–†‡ˆ‡•‡•ȋ ‹‰—‡œ‡–ƒŽǤǡ ʹͲͲͷȌǤ ”‡˜‹‘—•Ž›ǡ ƒ†ƒ ƒŽ‰ƒ†‘ ‡– ƒŽǤ ȋʹͲͳ͵Ȍ ”‡’‘”–‡† –Šƒ– Salmonella typhimurium ™ƒ• …ƒ’ƒ„Ž‡ ‘ˆ ‹†—…‹‰ ƒ †‡ˆ‡•‡ ”‡•’‘•‡ ‹ …Žƒ†‘†‡• ‘ ’Žƒ–•ǡ ƒ ”‡•’‘•‡ –Šƒ– ƒˆˆ‡…–‡† –Š‡ „ƒ…–‡”‹ƒŽ ’‘’—Žƒ–‹‘Ǥ Š‡› ƒŽ•‘ ”‡’‘”–‡† –Šƒ– •—…Š ƒ ”‡•’‘•‡ ™ƒ• ‘– ‡˜‹†‡– ‹ ˆ”‡•ŠǦ…—– …Žƒ†‘†‡• ƒ† „ƒ…–‡”‹ƒŽ ’‘’—Žƒ–‹‘ ‹…”‡ƒ•‡† ™‹–Š –‹‡Ǥ Š‡ ”‡•‡ƒ”…Š ‘ˆ …Š‹‘”ƒ ‡– ƒŽǤ ȋʹͲͲͺȌ ‘ Arabidopsis —–ƒ–• ™‹–Š †‡ˆ‡…–‹˜‡ •›•–‡‹… ƒ…“—‹”‡† ”‡•‹•–ƒ…‡ ȋȌ †‡ˆ‡•‡ •Š‘™‡† –Šƒ–  ƒŽ‘‰ ™‹–Š –Š‡ Š›’‡”•‡•‹–‹˜‡ ”‡•’‘•‡ ȋȌ ™‡”‡ ƒ…–‹˜ƒ–‡† „› •—”ˆƒ…‡ •–”—…–—”‡•’”‡•‡–‘Salmonella”‡…‘‰‹œ‡†„›–Š‡’Žƒ–ƒ†–Šƒ–Salmonella…‘—Ž†…‘Ž‘‹œ‡ ‡š–‡•‹˜‡Ž›–Š‡—–ƒ–’Žƒ–•–‘ƒŠ‹‰Š‡”Ž‡˜‡Ž…‘’ƒ”‡†–‘’Žƒ–•™‹–Šƒƒ…–‹˜‡†‡ˆ‡•‡Ǥ  –Š‹• •–—†›ǡ ™‡ …‘’ƒ”‡† –Š‡ ”‡•’‘•‡ ‘ˆ –™‘ …ƒ…–—• …—Ž–‹˜ƒ”• ‹ –Š‡ ’”‡•‡…‡ ‘ˆ –Š”‡‡ Salmonella •–”ƒ‹•ǡ –™‘ ‹•‘Žƒ–‡• ˆ”‘ ‘’ƒŽ …Žƒ†‘†‡• ȋͶ ƒ† ͹Ȍ ƒ† ‘‡ …‘‡”…‹ƒŽŽ› ƒ˜ƒ‹Žƒ„Ž‡ •–”ƒ‹ ȋƒŽͶȌ –‘ ‹˜‡•–‹‰ƒ–‡ –Š‡ †‡ˆ‡•‡ ”‡•’‘•‡ ƒ† –Š‡ ƒ„‹Ž‹–› ‘ˆ Salmonella •–”ƒ‹• –‘ ’‡”•‹•– ‹–‘ –Š‡ –‹••—‡Ǥ —” ”‡•—Ž–• ƒ”‡ …‘•‹•–‡– ™‹–Š –Š‡ ’”‡˜‹‘—• •–—†‹‡•ȋ ‹‰—‡œ‡–ƒŽǤǡʹͲͲͷǢƒ†ƒƒŽ‰ƒ†‘‡–ƒŽǤǡʹͲͳ͵Ǣ…Š‹‘”ƒ‡–ƒŽǤǡʹͲͲͺȌƒ†…‘ˆ‹” –Šƒ–SalmonellaŠƒ•–Š‡ƒ„‹Ž‹–›–‘ƒ…–‹˜ƒ–‡•‹‰ƒŽ•–Šƒ–‹†—…‡ƒ‹‘’ƒŽ’Žƒ–•ƒ†…‘—Ž† •—‰‰‡•– –Šƒ– –Š‡”‡ ‹• ‘– ƒ •’‡…‹ˆ‹… ’Žƒ–Ǧ„ƒ…–‡”‹— ‹–‡”ƒ…–‹‘ „‡…ƒ—•‡ ‘ …Šƒ”ƒ…–‡”‹•–‹… †‹ˆˆ‡”‡…‡•™‡”‡ˆ‘—†„‡–™‡‡•›’–‘•‹†—…‡†„›Salmonella•–”ƒ‹•‹‘’ƒŽ…—Ž–‹˜ƒ”•Ǥ CONCLUSIONS ‡‰‡–ƒ„Ž‡’ƒ†•‘ˆ…ƒ…–—•…—Ž–‹˜ƒ”•Ǯ‹Ž’ƒŽ–ƒǯƒ†Ǯ–Ž‹š…‘ǯ”‡•’‘†‡†–‘Salmonella‹ ƒ •‹‹Žƒ” ™ƒ›ǡ ƒ ”‡•’‘•‡ …Šƒ”ƒ…–‡”‹œ‡† „› ƒ ”ƒ’‹† ‡…”‘•‹• ‘ˆ –Š‡ –‹••—‡ǡ ƒ† ƒ ‡ƒ”Ž› †‡…”‡ƒ•‡ ‹ –Š‡ „ƒ…–‡”‹ƒŽ ’‘’—Žƒ–‹‘Ǥ Š‹• ”‡•’‘•‡ …‘—Ž† „‡ …‘•‹†‡”‡† ƒ Š›’‡”•‡•‹–‹˜‡ ”‡•’‘•‡ǤSalmonellaŠƒ•–Š‡ƒ„‹Ž‹–›–‘’‡”•‹•–‹–Š‡…ƒ…–—•–‹••—‡ˆ‘”ͶͺŠ‘”Ž‘‰‡”Ǥ ACKNOWLEDGEMENTS ‡–Šƒ–Š‡ƒ–‹‘ƒŽ‘—…‹Ž‘ˆ…‹‡…‡ƒ†‡…Š‘Ž‘‰›ȋȌˆ‘”•…Š‘Žƒ”•Š‹’ ͳ͸Ͷͻ͸ͷ‰”ƒ–‡†–‘–Š‡ˆ‹”•–ƒ—–Š‘”Ǥ‡ƒŽ•‘–Šƒƒ–‡‘ƒ”‰ƒ•‡”ƒƴ †‡œˆ‘”Š‹•ƒ••‹•–ƒ…‡ ™‹–Š–Š‡•–ƒ–‹•–‹…ƒŽƒƒŽ›•‹•Ǥ Literaturecited ‘ǤȋͳͻͻͶȌǤ”‘›‡…–‘ǦͳͲͻǦͳǦͳͻͻͶǤ”‘…‡†‹‹‡–‘•’ƒ”ƒŽƒ–‘ƒǡƒ‡Œ‘›”ƒ•’‘”–‡†‡—‡•–”ƒ•†‡ Ž‹‡–‘•’ƒ”ƒ•—ƒƴ Ž‹•‹•‹…”‘„‹‘Ž‘ƴ ‰‹…‘Ǥ‹ƒ”‹‘ˆ‹…‹ƒŽ†‡Žƒ ‡†‡”ƒ…‹‘ƴ Ǥ‡ƴ š‹…‘ǡǤ Ǥȋ‡š‹…‘‹–›ǡ‡š‹…‘ȌǤ ‡”ƒƴ †‡œǦ‰—‹ƒ‘ǡǤǤǡƒ†ƒǦƒŽ‰ƒ†‘ǡǤǡ‘”ƒǦ‰—‹Ž‡”ƒǡ Ǥǡ•Žƒ˜ƒǦƒ’‘•ǡǤǤǡƒŽŽǡ ǤǤǡ‘”–‘Ǧ ‡––ǡǤǤǤǡ ƒ†—…Šƒ•›ǡ ǤǤȋʹͲͲͻȌǤŠƒ”ƒ…–‡”‹œƒ–‹‘‘ˆSalmonella•’’Ǥˆ”‘‘’ƒŽŽ‡ƒ˜‡•ƒ†ƒ••‘…‹ƒ–‡†•‘‹Žƒ†™ƒ–‡” •ƒ’Ž‡• ‹ ‘”‡Ž‘•ǡ ‡š‹…‘Ǥ ƒ’‡” ’”‡•‡–‡† ƒ–ǣ —ƒŽ ‡‡–‹‰ ‘ˆ –Š‡ –‡”ƒ–‹‘ƒŽ ••‘…‹ƒ–‹‘ ‘ˆ ‘‘† ”‘–‡…–‹‘Ǥ ‹‰—‡œǡ ǤǤǡ ‘‰ǡ Ǥǡ ƒ”–‡”ǡ ǤǤǡ Š‡”ǡ ǤǤǤǡ –‘‡ǡ ǤǤǡ ƒ† ”‹’Ž‡––ǡ ǤǤ ȋʹͲͲͷȌǤ ‡‰—Žƒ–‹‘ ‘ˆ ‡–‡”‹… ‡†‘’Š›–‹… „ƒ…–‡”‹ƒŽ …‘Ž‘‹œƒ–‹‘ „› ’Žƒ– †‡ˆ‡•‡•Ǥ ‘ŽǤ Žƒ– ‹…”‘„‡ –‡”ƒ…–Ǥ 18 ȋ2Ȍǡ ͳ͸ͻȂͳ͹ͺ Š––’ǣȀȀ†šǤ†‘‹Ǥ‘”‰ȀͳͲǤͳͲͻͶȀ ǦͳͺǦͲͳ͸ͻǤ—„‡†



 

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ƒ†ƒƒŽ‰ƒ†‘ǡǤǡ‡”ƒƴ †‡œǦ‰—‹ƒ‘ǡǤǤǡƒ”‰ƒ•‡”ƒƴ †‡œǡǤǡ•Žƒ˜ƒƒ’‘•ǡǤǤǡŠƒ‹†‡œ—‹”‘œǡǤǡƒ† ƒ–‡Žǡ Ǥ ȋʹͲͳ͵ȌǤ ‡”•‹•–‡…‹ƒ †‡ Salmonella ›’Š‹—”‹— ‡ ‘’ƒŽ ˜‡”†—”ƒ ȋOpuntia ficusǦindicaȌǤ ‡˜Ǥ ‹–‘–‡…Ǥ ‡šǤ36ǡͳͶ͹Ȃͳͷ͵Ǥ ƒ†‹‰ƒǡǤǤǡƒ”–‹‘ǡ ǤǤǡƒ†ƒ”‡”ǡ ǤǤȋʹͲͲͳȌǤ‹‘Ž‘‰Çƴƒ†‡Ž‘•‹…”‘‘”‰ƒ‹•‘•ǡͺ–Š”‡˜Ǥ‡†ȋ‡š‹…‘‹–›ǡ ‡š‹…‘ǣ”‡–‹…‡ƒŽŽȌǡ’’Ǥͻͺ͸Ǥ … —‹”‡ǡǤ ǤȋͳͻͻʹȌǤ‡’‘”–‹‰‘ˆ‘„Œ‡…–‹˜‡…‘Ž‘”‡ƒ•—”‡‡–•Ǥ‘”–…‹‡…‡27ǡͳʹͷͶȂͳʹͷͷǤ …Š‹‘”ƒǡǤǡƒ””‡”‹ǡǤǡŠƒ”’‡–‹‡”ǡǤǡƒ†‹”–ǡǤȋʹͲͲͺȌǤŠ‡†ƒ”•‹†‡‘ˆ–Š‡•ƒŽƒ†ǣSalmonellatyphimurium ‘˜‡”…‘‡• –Š‡ ‹ƒ–‡ ‹—‡ ”‡•’‘•‡ ‘ˆ Arabidopsis thaliana ƒ† •Š‘™• ƒ ‡†‘’ƒ–Š‘‰‡‹… Ž‹ˆ‡•–›Ž‡Ǥ ‘ 3ȋ5Ȍǡ‡ʹʹ͹ͻŠ––’ǣȀȀ†šǤ†‘‹Ǥ‘”‰ȀͳͲǤͳ͵͹ͳȀŒ‘—”ƒŽǤ’‘‡ǤͲͲͲʹʹ͹ͻǤ—„‡† …Š‹‘”ƒǡǤǡ‹”Ž‘‰‡—šǦƒ›ƒ–ǡ Ǥǡ—‡•‘ǡǤǡ ƒ”…‹ƒǡǤǤǡ‹Žƒ—ǡǤǡŠƒ””‹‡”ǡǤǡ‡ŽŽ‡–‹‡”ǡǤǡ‡ƒ–‡ƒ—ǡǤǡƒ……ƒ”‹‹ǡ Ǥǡ‡Ž‰‡ǡǤǡƒ†‹”–ǡǤȋʹͲͳͳȌǤ‘•‡”˜ƒ–‹‘‘ˆƒŽ‘‡ŽŽƒ‹ˆ‡…–‹‘‡…Šƒ‹••‹’Žƒ–•ƒ†ƒ‹ƒŽ•Ǥ‘ 6ȋ9Ȍǡ‡ʹͶͳͳʹŠ––’ǣȀȀ†šǤ†‘‹Ǥ‘”‰ȀͳͲǤͳ͵͹ͳȀŒ‘—”ƒŽǤ’‘‡ǤͲͲʹͶͳͳʹǤ—„‡†

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