Data/hora: 03/06/2024 18:37:31

Provedor de dados: 	Electronic Journal of Biotechnology	
País: 	Chile	
Título: 	Effects of 5-aminolevulinic acid (ALA)-containing supernatants from selected Rhodopseudomonas palustris strains on rice growth under NaCl stress, with mediating effects on chlorophyll, photosynthetic electron transport and antioxidative enzymes	
Autores: 	Nunkaew,Tomorn; Kantachote,Duangporn; Kanzaki,Hiroshi; Nitoda,Teruhiko; Ritchie,Raymond J.	
Data: 	2014-01-01	
Ano: 	2014	
Palavras-chave: 	5-Aminolevulinic acid (ALA); Antioxidative enzymes; Chlorophyll fluorescence; Rhodopseudomonas palustris; Rice; Salinity.	
Resumo: 	Background: Rice is globally one of the most important food crops, and NaCl stress is a key factor reducing rice yield. Amelioration of NaCl stress was assessed by determining the growth of rice seedlings treated with culture supernatants containing 5-aminolevulinic acid (ALA) secreted by strains of Rhodopseudomonas palustris (TN114 and PP803) and compared to the effects of synthetic ALA (positive control) and no ALA content (negative control). Results: The relative root growth of rice seedlings was determined under NaCl stress (50 mM NaCl), after 21 d of pretreatment. Pretreatments with 1 &amp;#956;M commercial ALA and 10X diluted culture supernatant of strain TN114 (2.57 &amp;#956;M ALA) gave significantly better growth than 10X diluted PP803 supernatant (2.11 &amp;#956;M ALA). Rice growth measured by dry weight under NaCl stress ordered the pretreatments as: commercial ALA N TN114 N PP803 N negative control. NaCl stress strongly decreased total chlorophyll of the plants that correlated with non-photochemical quenching of fluorescence (NPQ). The salt stress also strongly increased hydrogen peroxide (H2O2) concentration in NaCl-stressed plants. The pretreatments were ordered by reduction in H2O2 content under NaCl stress as: commercial ALA N TN114 N PP803 N negative control. The ALA pretreatments incurred remarkable increases of total chlorophyll and antioxidative activities of catalase (CAT), ascorbate peroxide (APx), glutathione reductase (GR) and superoxide dismutase (SOD); under NaCl stress commercial ALA and TN114 had generally stronger effects than PP803. Conclusions: The strain TN114 has potential as a plant growth stimulating bacterium that might enhance rice growth in saline paddy fields at a lower cost than commercial ALA.	
Tipo: 	Journal article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100004	
Editor: 	Pontificia Universidad Católica de Valparaíso	
Formato: 	text/html	
Fonte: 	Electronic Journal of Biotechnology  v.17 n.1 2014