GM MUSTARD

• Hybridisation involves crossing two genetically dissimilar plant varieties that can be from the same species.
• The first generation (F1) offspring from such crosses tend to have higher yields than that of parents.
• Such hybridisation is not easy in mustard, as its flowers are bisexual and make the plants largely self-pollinating.
• Since the eggs of one plant cannot be fertilised by the pollen grains from another, it limits the scope for developing hybrids unlike cotton, maize, and tomato, where this can be done through simple emasculation/physical removal of anthers.
• By Genetic Modification, scientists have developed the hybrid mustard DMH-11 containing two alien genes isolated from a soil bacterium called Bacillus amyloliquefaciens.
• The first gene codes for a protein that impairs pollen production & makes the plant into male-sterile.
• This plant is then crossed with a fertile parental line containing in turn, the second gene that blocks the action of the first gene.
• The resultant F1 progeny is both high-yielding & capable of producing seed/grain.
• The scientists have deployed the barnase-barstar (1st & 2nd genes), GM technology to create a robust & viable hybridisation system in mustard.
• This system was used to develop DMH-11 by crossing a popular Indian mustard variety 'Varuna' with an East European 'Early Heera-2' mutant.
• DMH-11 is claimed to have shown an average 28% yield increase over Varuna in contained field trials carried out by ICAR.

• GEAC is a responsible body for the appraisal of proposals relating to the release of GM organisms into the environment.
• It has recommended the release of DMH-11 for its seed production & testing, before commercial release.
• It has given the green signal for commercial cultivation by farmers, with the production of seeds being the first step.
• GEAC recommended the environmental release of DMH-11's parental lines to develop new hybrids, which can give higher yields than DMH-11.
• Mustard varieties in India have a narrow genetic base.
• The barnase-barstar system enables the breeding of hybrids from a wider range of mustards, including those of East European origin like Heera, and Donskaja.
• There were two specific concerns about GM mustard.
• The first is the presence of a third 'bar' gene, which makes GM mustard plants tolerant to the spraying of glufosinate ammonium, a chemical used for killing weeds.
• DMH-11 developers say that the bar gene is only a marker gene.
• It is used to identify those plants that were GM, the non-GM ones that cannot withstand the application of herbicide & necessary for large-scale seed production.
• GEAC recommended the usage of any formulation of herbicide, exclusively for hybrid seed production.
• The second concern is over GM mustard threatening / undermining the population of honeybees.
• Mustard flowers are a source of nectar for honeybees & many other pollinator insects.
• Based on the examination of scientific evidence available, it seems that the bar, barnase, and barstar system will pose an adverse impact on honey bees & other pollinators.