237 KB0 KB200420252007Assefa, FasilHiskias, YaynuKuarabachew, Henokštevilka:2letnik:90str. 125-135ISSN:1581-9175COBISSID:2216840URN:URN:NBN:SI:doc-8IPVM0E2enUniverza v Ljubljani, Biotehniška fakultetaActa agriculturae Slovenicabiološka kontrolafitofarmacevtska sredstvakrompirkrompirjeva ovelostmikrobiologijaEvaluation of Ethiopian isolates of Pseudomonas fluorescens as biocontrol agent against potato bacterial wilt caused by Ralstonia (Pseudomonas) solanacearum| Ocena etiopskih izolatov Pseudomonas fluorescens kot sredstva za biološko zatiranje krompirjeve ovelosti, ki jo povzroča Ralstonia (Pseudomonas) solanacearum|A total of 50 fluorescent pseudomonas were collected from different potato growing areas in Ethiopia isolated and characterized, and evaluated on king's B medium for their antibiosis towards Ralstonia solanacearum the pathogen of bacterial wilt of potato. Out of the 50 isolates only three i.e., Pf S2, Pf Wt3 and PfW1 showed inhibition against the growth of the pathogen. To test their antagonistic effect under greenhouse condition an experiment was conducted using sterilized soil. Tubers of bacterial wilt susceptible potato clone CIP 383031.15 were used. The potato tubers were dipped into 48 hrs old culture suspension of the three isolates i.e., Pf S2, Pf Wt3, PfW1 and Pfri (Indian reference strain) for 1 hr and planted in pots containing sterilized soil. Bacterization of tubers with isolates Pf S2, Pf Wt3, and PfW1, significantly reduced by 59.83% the incidence of bacterial wilt compared to the pathogen-inoculated control and increased plant growth (plant height and dry weight) by 59.83%, 76.89% and 28.44%, respectively. This suggests the importance of the studied isolates as plant growth-promoting rhizobacteriaZbrali in opisali smo 50 fluorescentnih pseudomonad z različnih področij v Etiopiji, kjer pridelujejo krompir in na KB gojišču ocenili njihov antibiotični učinek na povzročitelja krompirjeve ovelosti, Ralstonio solanaceum. Od 50 izolatov so samo trije, Pf S2, Pf Wt3 in PfW1 inhibirali rast patogena. Da bi ocenili njihovo agonistično delovanje pod pogoji v rastlinjaku, smo naredili poskus s sterilizirano zemljo. Uporabili smo gomoljena ovelost občutljivega klona krompirja CIP 383031.15. Krompirjeve gomolje smo potopili v 48 ur staro kulturo treh izolatov Pf S2, Pf Wt3, PfW1 in Pfri (indijski referenčni sev) ya eno uro in posadili v lončke s sterilno zemljo. Okužba gomoljev z izolati Pf S2, Pf Wt3 in PfW1 je značilno znižala pogostnost baketrijske ovelosti za 59,83 % v primerjavi s kontrolno okuženimi rastlinami in izboljšala rast rastlin (višina rastlin in suha snov) za 59,83 %, 76,89 % oziroma 28,44 %. To nakazuje pomen proučevanih izolatov kot rast spodbujajočih rizobakterijTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Biotehniška fakulteta