Oceanospirillum nioense sp. nov., a marine bacterium isolated from sediment sample of Palk bay, India

A novel Gram-negative, spiral shaped, motile bacterium, designated strain NIO-S6^T, was isolated from a sediment sample collected from Off-shore Rameswaram, Tamilnadu, India. Strain NIO-S6^T was found to be positive for oxidase, DNase and lysine decarboxylase activities and negative for catalase, gelatinase, lipase, ornithine decarboxylase, nitrate reductase, aesculinase, amylase and urease activities. The fatty acids were determined to be dominated by C_10:0 3OH, C_16:0, C_16:1 and C_18:1. Strain NIO-S6^T contains Q-8 as the major respiratory quinone. The DNA G+C content of the strain NIO-S6^T was determined to be 49.5 ± 0.6 mol %. Phylogenetic analysis based on 16S rRNA gene sequence of strain NIO-S6^T indicated Oceanospirillum linum and Oceanospirillum maris of the family Oceanospirillaceae (phylum Proteobacteria) are the closest related species with sequence similarities of 98.4 and 97.8 % respectively. Other members of the family showed sequence similarities <96.4 %. However, DNA–DNA hybridization with Oceanospirillum linum LMG 5214^T and Oceanospirillum maris LMG 5213^T showed a relatedness of 31.5 and 46.9 % with respect to strain NIO-S6^T. Based on the phenotypic characteristics and on phylogenetic inference, strain NIO-S6^T is proposed as a novel species of the genus Oceanospirillum as Oceanospirillum nioense sp. nov. and the type strain is NIO-S6^T (=MTCC 11154^T = KCTC 32008^T).     

Drip Irrigation as a Delivery System for Infestation of Field Plots with Nematodes

A drip irrigation delivery system was used to infest field sites with the plant-parasitic root-knot nematodes, Meloidogyne incognita. Juvenile or egg inocula passed through the system without blockage of emitters or harm to the nematodes. Field sites so infested were available for experimentation. Delivery of approximately 5 x 10⁴ to 10⁵ juveniles or 10⁵ to 3 x 10⁵ eggs per emitter through the drip system resulted in heavy root galling of tomatoes planted next to the drip emitters. Nematodes feeding on bacteria (Acrobeloides sp.) and on fungi (Deladenus durus) also were successfully applied through the drip system. This method has potential for uniformly infesting experimental sites with plant-parasitic or entomogenous nematodes and for manipulation of nematode community structure for soil ecological studies.