RESUMEN
In this study, a double-tube centrifuge method was employed to determine the effects of soil moisture on the bioactivity of cafenstrole, pretilachlor, benfuresate, oxyfluorfen and simetryn. In general, the available herbicide concentration in soil solution (ACSS) showed little change as soil moisture increased for herbicides. The total available herbicide in soil solution (TASS) typically increased as soil moisture increased for all herbicides. The relationship between TASS and % growth rate based on dry weight showed strong linear relationships for both cafenstrole and pretilachlor, with r2 values of 0.95 and 0.84, respectively. Increasing TASS values were consistent with increasing herbicide water solubility, with the exception of the ionizable herbicide simetryn. Plant absorption and % growth rate exhibited a strong linear relationship with TASS. According to the results suggested that TASS was a better predictor of herbicidal bioactivity than ACSS for all herbicides under unsaturated soil moisture conditions.
Asunto(s)
Herbicidas/análisis , Herbicidas/química , Suelo/química , Adsorción , Disponibilidad Biológica , Herbicidas/farmacocinética , Solubilidad , AguaRESUMEN
Strains JC15(T) and JC19 were isolated from samples collected from different locations in India, including a coal mine and a marine lagoon. Both strains were Gram-stain-negative rods, motile by means of a single polar flagellum, catalase- and oxidase-positive, and hydrolysed casein, produced H(2)S and showed beta-haemolysis. Strain JC15(T) grew optimally at pH 6 (range pH 5-8) while strain JC19 grew optimally at pH 7 (range pH 6-9) and both had a growth temperature optimum of 30-37 degrees C (range 22-40 degrees C). Both strains could grow chemo-organoheterotrophically and chemolithoautotrophically. Neither strain required NaCl for growth and both could tolerate up to 9 % (w/v) NaCl, with optimum growth at 5 % NaCl. Vitamin B(12) was required as a growth factor by both strains. The major fatty acids were iso-C(15 : 0), C(17 : 1)omega8c and iso-C(13 : 0) 3-OH. The DNA G+C contents of strains JC15(T) and JC19 were 53.6 and 54.3 mol%, respectively. A phylogenetic tree based on 16S rRNA gene sequence analysis showed that strains JC15(T) and JC19 were most closely related to Shewanella haliotis DW01(T) (approximately 94 % sequence similarity) and to other members of the genus Shewanella. Genomic relatedness (DNA-DNA hybridization) between strains JC15(T) and JC19 is 88 %. On the basis of phenotypic and molecular genetic evidence, strain JC15(T) represents a novel species of the genus Shewanella, for which the name Shewanella fodinae sp. nov. is proposed. The type strain is JC15(T) (=CCUG 57102(T) =NBRC 105216(T) =KCTC 22506(T)).
Asunto(s)
Agua de Mar/microbiología , Shewanella/clasificación , Composición de Base , Secuencia de Bases , Carbón Mineral , Minería , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Shewanella/genética , Shewanella/aislamiento & purificaciónRESUMEN
A Gram-negative, motile, rod-shaped, facultatively anaerobic bacterium was isolated from sediment of Chilika Lagoon, a brackish water lagoon in India. The strain, designated JC5(T), was able to grow in the presence of 0-8.0 % NaCl and at pH 7.0-10.0. The isolate was positive for oxidase and catalase and exhibited alpha-haemolysis. The major fatty acids were iso-C(15 : 0) (18.3 %), C(16 : 0) (11.3 %), C(17 : 1)omega8c (13.1 %) and a summed feature, C(16 : 1)omega7c and/or C(16 : 1)omega6c (15.1 %). The genomic DNA G+C content was 54.6 mol%. A phylogenetic tree based on the 16S rRNA gene sequences showed that strain JC5(T) forms a lineage within the genus Shewanella and is closely related to Shewanella haliotis DW01(T) (98.0 %), Shewanella algae ATCC 51192(T) (97.6 %) and Shewanella marina C4(T) (95.8 %). Further, genomic DNA-DNA hybridization of strain JC5(T) with S. haliotis DW01(T) and S. algae ATCC 51192(T) showed relatedness of only 42 and 23 %, respectively. On the basis of phenotypic and molecular genetic evidence, strain JC5(T) represents a novel species of the genus Shewanella, for which the name Shewanella chilikensis sp. nov. is proposed. The type strain is JC5(T) (=CCUG 57101(T) =NBRC 105217(T) =KCTC 22540(T)).
Asunto(s)
Álcalis/metabolismo , Sedimentos Geológicos/microbiología , Agua de Mar/microbiología , Shewanella/clasificación , Shewanella/aislamiento & purificación , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Shewanella/genética , Shewanella/metabolismoRESUMEN
A soil isolate, which had been assigned to the genus Nocardia, was shown to have properties consistent with its classification in the genus Amycolatopsis. An almost complete nucleotide sequence of the 16S rDNA of the strain was determined following cloning and sequencing of the amplified gene. The sequence was aligned with those available for members of the family Pseudonocardiaceae and related taxa and phylogenetic trees were inferred using three tree-making algorithms. The organism consistently formed a distinct monophyletic clade with the type strain of Amycolatopsis methanolica, but DNA-DNA relatedness data showed that the two strains belonged to distinct genomic species. The organism was also distinguished from the type strains of all validly described species of Amycolatopsis using a battery of phenotypic properties. The genotypic and phenotypic data show that the strain merits recognition as a new species of the genus Amycolatopsis. The name proposed for the new species is Amycolatopsis thermoflava sp. nov. The type strain is IFO 14333T.
Asunto(s)
Actinomycetales/clasificación , Actinomycetales/genética , ADN Ribosómico/genética , ARN Ribosómico 16S/genética , Microbiología del Suelo , Actinomycetales/fisiología , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADNRESUMEN
An actinomycete strain, 'Nocardai flavorosea' JCM 3332, was found to have properties consistent with its classification in the genus Nocardia. An almost complete gene sequence of the 16S rDNA of the strain was determined following cloning and sequencing of the amplified gene. The sequence was aligned with those available for nocardiae and phylogenetic trees were inferred using four tree-making algorithms. The organisms consistently formed a distinct clade with the type strain of Nocardia carnea. However, DNA relatedness experiments showed that the strain and N. carnea DSM 43397T belonged to two distinct genomic species. The organism was also distinguished from representative of all of the validly described species of Nocardia using a combination of phenotypic properties. These genotypic and phenotypic data show that the strain merits recognition as a new species of the genus Nocardia. The name proposed for the new species of is Nocardia flavorosea sp. nov. The type strain is JCM 3332T.