Natural Endophytic Occurrence of Acetobacter diazotrophicus in Pineapple Plants

Abstract

The presence of endophytic Acetobacter diazotrophicus was tested for pineapple plants (Ananas comosus [L.] Merr.) grown in the field. Diazotrophic bacteria were isolated from the inner tissues of surface sterilized roots, stems, and leaves of pineapple plants. Phenotypic tests permitted the selection of presumptive nitrogen-fixing A. diazotrophicus isolates. Restriction fragment length polymorphisms (RFLPs) of small subunit (SSU) rDNA using total DNA digested with endonuclease SphI and with endonuclease NcoI, hybridizations of RNA with an A. diazotrophicus large subunit (LSU) rRNA specific probe, as well as patterns in denaturing protein electrophoresis (SDS-PAGE) and multilocus enzyme tests allowed the identification of A. diazotrophicus isolates. High frequencies of isolation were obtained from propagative buds that had not been nitrogen-fertilized, and lower frequencies from 3-month-old plants that had been nitrogen-fertilized. No isolates were recovered from 5- to 7-month-old nitrogen-fertilized plants. All the A. diazotrophicus isolates recovered from pineapple plants belonged to the multilocus genotype which shows the most extensive distribution among all host species previously analyzed. </hea

History on the biological nitrogen fixation research in graminaceous plants: special emphasis on the Brazilian experience

“…Until quite recently, it was thought that G. diazotrophicus could only occur in plants that propagate vegetatively such as sugarcane, sweet potato (Paula et al 1990, Döbereiner et al 1993) and pineapple (Tapia-Hernandez et al 2000). However, it was detected in plants propagated by seeds such as the grass Eleusine coracana (Loganathan et al 1999) and in coffee (Fuentes-Ramirez et al 2001), although these observations refer to the new species mentioned above, G. johannae and G. azotocaptans.…”

Seleção de bactérias promotoras de crescimento no abacaxizeiro cultivar Vitória durante a aclimatização

“…Os mecanismos de promoção de crescimento pelas bactérias epifíticas e endofíticas incluem diferentes ações, como a fixação biológica de nitrogênio (KuKlinsky-Sobral et al, 2004), solubilização de fosfatos (Chabot et al, 1998;Verma et al, 2001), biossíntese de fito-hormônios (Lucangeli & Bottini, 1997), influência na atividade enzimática da 1-aminociclopropano 1-carboxilato (ACC) deaminase (Rothballer at al., 2008), controle biológico (Byrne et al, 2005), síntese de sideróforos (Lacava et al, 2008) e indução de resistência sistêmica a patógenos na planta hospedeira (Kloepper et al, 1999 Efeitos positivos da inoculação de bactérias promotoras de crescimento foram verificados na abacaxicultura, principalmente quando as bactérias inoculadas também são fixadoras de nitrogênio atmosférico (Weber et al, 2003). Já foram isoladas de abacaxizeiros bactérias diazotróficas pertencentes aos gêneros Burkholderia (Weber et al, 1999), Acetobacter (Tapia-Hernández et al, 2000) e Asaia (Weber et al, 2003). No entanto, dados sobre a real utilização desses microrganismos como inoculantes ou na formulação de biofertilizantes ainda são escassos.…”

Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

“…Notably, the N-fixing and phosphate-solubilizing bacteria promote plant growth and development. For pineapple diazotrophs were isolated of the genera Burkholderia, Herbaspirillum (Weber et al, 1999), Acetobacter (Tapia-Hernández et al, 2000) and Asaia (Weber et al, 2003), with the actual possibility of using these microorganisms as growth promoters of the host plant (Weber et al, 2010;Baldotto et al, 2010).…”