Production of streptomycete inoculum in sterilized rice

Abstract

Actinomycetes are important plant disease control and growth promotion agents, which makes it necessary to develop technology to produce large quantities of inoculum for green-house and field work. The present study had the objective of evaluating the growth of several isolates of Streptomyces in sterile rice for inoculum production. The sterile rice was inoculated with isolates of S. thermotolerans, S. griseus subsp. griseus, Streptomyces sp. N0035, S. purpurascens, and Streptomyces sp., and incubated at 28 ± 2ºC. Five days after its inoculation, mycelial growth and sporulation was observed for all Streptomyces isolates on the rice grains. Twelve days after incubation, the colonized rice was transferred to envelopes of dark brown paper and let to dry in an incubator at 30ºC for three days. After drying, 1g of colonized rice was added to 200 mL of sterile distilled water and the number of spores was counted under a microscope with a Newbauer counting chamber. Spore production varied from 0.14 × 10 9 to 1.47 × 10 9 spores per gram of rice and differed among the Streptomyces species. Sterile rice can be an alternative substrate for low cost mass production of Streptomyces inoculum.

Evaluation of the biocontrol efficacy of a Serratia marcescens strain indigenous to tea rhizosphere for the management of root rot disease in tea

“…Pathogen inoculum was prepared following the method of Soares et al [ 61 ]. For this, 300 g of rice grains were soaked in 500 mLof distilled water at room temperature for one hour for proper hydration.…”

From Isolation of Phosphate Solubilizing Microbes to Their Formulation and Use as Biofertilizers: Status and Needs

“…In order to reduce the use of chemicals for mass production, several cost-effective substrates have been tested successfully. For instance, Soares et al (2007) and Diraviyam et al (2011), have shown that sterile moistened rice, rice bran, wheat bran and sugarcane residues can be viable methods for inoculum mass production of Actinobacteria. Despite of this innovation, research must be continued to test natural, inexpensive and available products for microbial biomass production.…”

Antagonistic Actinomycetes Mediated Resistance in Solanum lycopersicon Mill. Against Rhizoctonia solani Kühn

“…The culture was centrifuged at 60009g for 5 min. The cell pellet was suspended in 0.85 % saline and the cell density was adjusted to 1.0 9 10 8 CFU mL -1 using spectrophotometer at 610 nm [19]. For mass production of pathogen, inoculum was prepared by growing R. solani in wheat bran (700 g in capacity flask; moisture level 50 %) and incubated for two weeks in the dark with proper mixing at regular intervals for uniform distribution of fungal mycelia.…”