By Jacob P. Koshy
June 22, 2009
The marker-assisted selection method is a faster way to improve crop quality to help raise yields
New Delhi: Prepare for a bouquet of super crops—genetically improved rice, wheat, soya bean, mustard and chickpea—over the next three years. The government, concerned at falling agricultural growth, launched a project in May to develop naturally improved crop varieties mainly to boost yields, said R.R. Sinha, an adviser at the department of biotechnology.
Unlike their genetically modified (GM) cousins, which are in various stages of field and lab trials in the country, these crops employ a middle-of-the-road approach called the marker-assisted selection (MAS) method.
In GM crops, foreign genes from a different species are artificially inserted into a crop. MAS, on the other hand, is a fast-forwarded version of the traditional method of improving crop quality, which involves selecting a few ideal specimen of a crop and repeatedly crossing these till they yield crops with the desired characteristics.
The traditional approach is time-consuming and, in some cases, a trait can be suitably expressed only after hundreds of crossings. In MAS, scientists use a technique called gene sequencing, by which they have been able to identify all the genes that make up certain crops, and importantly the markers—stray pieces of DNA—that tag along.
It’s easier looking for a marker than a gene. “We just look for the markers and with that we can achieve desired traits within 10 crossings at times,” said Sinha.
Last year, the government announced the creation of the first indigenously developed seed variety using MAS: a hybrid maize called FQH 4567 that has 40% higher protein content than other varieties.
Buoyed by its success, the government has extended this approach to other crops, say scientists. “That, and there are still reservations even among some people in the government of the effects of genetically engineered food products,” said a scientist at the department of biotechnology. He didn’t want to be identified.
The government also plans to use MAS to improve yields of crops, which includes inducing pest-resistant qualities. A government document, viewed by Mint, that lists the crops to be improved states that except for wheat and maize, the other projects deal with imparting resistance to insects, blights, temperature, stress and flooding.
MAS doesn’t involve isolating and inserting genes from other organisms into crops and thus obviates the need for time-consuming ethical clearances and “fears surrounding inserting genes into crops,” said Sinha. “Of course, in situations where there’s no way out but to insert a gene, we will use it,” he added.
Experts say that increasing yield was top priority, whether the route was genetic engineering or marker-assisted breeding. “Since the 1980s our yields have been at an all-time low. With the effects of climate change and fluctuating rainfall patterns already making themselves apparent, we need any environmentally sound method to push yields,” said M.S. Swaminathan, an agricultural scientist credited with the Green Revolution of the 1970s in the country.
India aims to double agricultural growth from 2% in the Ninth Plan and early years of the 10th Plan to 4% in the 11th Plan (2007-12). The projected allocation for agriculture and irrigation in this period is pegged at Rs1.21 trillion, more than double the sum spent for these between 2002 and 2007.