With the emergence of transgenic technologies, new ways to improve the agronomic performance of crops for food, feed, and processing applications have been devised. In addition, ability to express foreign genes using transgenic technologies has opened up options for producing large quantities of commercially important industrial or pharmaceutical products in plants. Despite this high adoption rate and future promises, there is a multitude of concerns about the impact of genetically modified (GM) crops on the environment. Potential contamination of the environment and food chains has prompted detailed consideration of how such crops and the molecules that they produce can be effectively isolated and contained. One of the reasonable steps after creating a transgenic plant is to evaluate its potential benefits and risks to the environment and these should be compared to those generated by traditional agricultural practices. The precautionary approach in risk management of GM plants may make it necessary to monitor significant wild and weed populations that might be affected by transgene escape. Effective risk assessment and monitoring mechanisms are the basic prerequisites of any legal framework to adequately address the risks and watch out for new risks. Several agencies in different countries monitor the release of GM organisms or frame guidelines for the appropriate application of recombinant organisms in agro-industries so as to assure the safe use of recombinant organisms and to achieve sound overall development. We feel that it is important to establish an internationally harmonized framework for the safe handling of recombinant DNA organisms within a few years.

Thirty seven bacterial cultures isolated from soil samples obtained from different locations were tested for their antagonistic activity against some fungal pathogens, viz., Sclerotium rolfsii, Fusarium oxysporum and Rhizoctonia solani, causal agents of collar rot of sunfl ower, wilts and root rots, respectively. Among them, 5 bacterial strains, viz., A1 6 (Bacillus sphaericus), K1 24 (Pseudomonas fl uorescens), M1 42 (Bacillus circulans), M1 66 (Bacillus brevis) and T1 22 (Bacillus brevis) showed positive antagonistic activity. M1 66 was the most effective in inhibiting mycelial growth of S. rolfsii in vitro followed by M1 42, T1 22, K1 24 and A1 6. Only one bacterial strain i.e. M1 42 exhibited antagonistic activity against F. oxysporum, and none of the bacterial strains gave positive activity against R. solani. Furthermore, antimicrobial activities of all the 5 strains were checked against different test organisms. It causes pre-and post-emergence damping off and collar rot of sunfl ower. The fungus spreads by mycelial contact with healthy plants and over-winters as sclerotia in soil. The sclerotia survive for a long period in soil and causes severe losses. The other fungal pathogen, F. oxysporum, an abundant and active saprophyte in soil and organic matter, has specifi c forms that are plant pathogenic 3 and cause wilts, root rots and damping off. Disease symptoms caused by R. solani, a very common soil borne pathogen with a great diversity of host plants, are referred to as damping-off, root rots and blights 4 . Due to high economic losses caused by fungal phytopathogens, biocontrol mechanisms are of great importance. In the present investigation, antagonistic effects of some bacterial strains have been examined against the above fungal pathogens with particular reference to antagonistic interaction. Also, the antimicrobial activities of these strains were checked against different test organisms.The 37 bacterial strains were isolated from soil samples by serial dilution agar plate technique. The bacterial strains were characterized according to Bergey's Manual of Systematic Bacteriology 5 . All the strains were purifi ed on Tryptic Soy Agar (TSA) and maintained as glycerol stock at -70°C. The fungal cultures used in the antagonistic studies were S. rolfsii (MTCC 288) (MTCC 277). These microorganisms were obtained from MTCC and Gene bank, IMTECH, Chandigarh, India. The fungal cultures were maintained in Potato Dextrose Agar (Hi-Media, Bombay, India) at 25ºC and the bacterial strains were maintained in Nutrient Agar (Hi-Media, Bombay, India) at 30ºC.Antagonistic properties of all bacterial strains were tested against S. rolfsii, R. solani and F. oxysporum on TSA plates using a dual culture technique 6 . Agar blocks (5 mm dia.) containing 5 days old mycelia were placed at the center of TSA plates. A loopful culture (24 h old) of bacterial strain was inoculated at 2 cm juxtaposed to the pathogen on each plate. The fungal pathogen was inoculated centrally on TSA plate. Uninoculated plates served as co...

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