Map of North East India showing sample collection site. 

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Context 1

... thereby killing all the beneficial microorganisms from the soil. Due to continuous use of chemical pesticides the pathogens become resistant to a wide spectrum of fungicides applied in the soil. The use of microbial biocontrol agents is an alternative approach for reducing the use of chemicals in agriculture because it is ecofriendly in nature and safe to use in agricultural system to increase crop productivity since the action of such bacteria is highly specific and cost effective. It has been sug- gested that these bacteria might interact more closely with the host plants and act as effective biocontrol agents in sustainable crop production. Several species of bacteria are known to have beneficial effect on plant growth promotion and disease suppression through production of plant growth promoting regulators and secondary metabolite substances. Organisms such as Burkholderia cepacia have shown effective in suppressing many plant diseases and also promote plant growth [3]. Recently, Burkholderia species has been classified into 10 geno- typically distinct but phenotypically similar species (genomovars) referring to the Burkholderia cepacia complex (Bcc) [4]. In this study, isolation and characterization of potential indigenous biocontrol bacteria IBSD-LKBI was reported from NE India for the control of two pathogens which caused wilt and damping-off diseases in French bean. The production of different hydrolytic enzymes and production of growth hormone and iron sequestering from soil has been studied. Moreover, this strain played significant functions in promoting growth on beans and this can further lead to the development of a potential bio-inoculants against soil borne fungal pathogens and also to study its ecological role and interactions with plant which can further lead to the development of a potential biocontrol packages/bioinoculants against soil borne fungal pathogens and also to study its ecological role and interaction with plants. Twenty five French bean field sites were selected from different locations representing the entire Imphal East and Imphal West valley zone of Manipur, which falls in the Indian region of Indo-Burma diversity hotspot of the world and part of other NE region, for the collection of rhizosphere sample. From each sites, 4 - 5 French bean roots along with the rhizosphere soils from both healthy and infected plants were randomly selected and uprooted during the winter seasons of 2006-2007. The collected samples were carried to the laboratory and stored in the freeze (4 ̊ C) prior to isolation of rhizosphere bacteria. The sampling site is given in Figure 1 . Northeast India has humid sub-tropical climate, ranging from hot to humid summers, severe monsoons with an average rainfall recorded around 10,000 mm and above and mild to chilled winter. Therefore, the variation in weather condition adds on to the exploration of indigenous microbes that which could adapt to changes in various environmental conditions and weather being one of the factors for varied applications. Ten grams of the root sample along with the rhizosphere soils were transferred to conical flasks with 90 ml of sterile physiological saline water and homogenized by shaking at 120 rpm for 30 mins Suspensions from the collected samples were serially diluted up to 10 –5 . One ml of the homogenates were spread over plates of King’s B agar medium, and Luria Bertani agar and incubated at 30 ̊ C for 24 - 48 h. Subsequently, the colonies of different colony characteristics and also with microscopi- cally different morphology were selected and purified by dilution streaks. The purified isolates were maintained at –80 ̊ C in 30% glycerol stock for further biochemical ...

Context 2

... collected samples were carried to the laboratory and stored in the freeze (4˚C) prior to isolation of rhizosphere bacteria. The sampling site is given in Figure 1. ...