Deepak Pental is Professor of Genetics at the University of Delhi. A former vice-chancellor, he’s at the centre of a scientific storm over transgenic mustard, the first such food crop that’s been cleared by the Environment Ministry’s technical committee for release into the fields. Dr. Pental’s group has used two genes from soil bacterium (Bacillus amyloliquefaciens), called barnase and barstar, that make mustard, a self-pollinating plant, amenable to hybridisation. Hybrid plants are generally considered higher yielding than pure, native parental cultivars. Activists opposed to GM technology, however, allege that Dr. Pental’s claims on yield are inflated, and that along with barnase and barstar he employs another gene, called bar, that make the mustard herbicide-tolerant, locking farmers into certain brands of weedicides. In a wide-ranging conversation, Dr. Pental explained why such allegations are baseless and why GM technology is vital to the future of Indian agriculture. Excerpts:
You have been working on the genetic transformation of mustard for many years now and had already developed a way to make mustard hybrids without using foreign genes in 2002. Why have a new transgenic technology now?
That was DMH-1 (Dhara Mustard Hybrid-1), the only hybrid released by the Indian Council for Agricultural Research (ICAR) after extensive field trials. That employed a different technique, called cytoplasmic male sterility (CMS). It’s effective but large-scale seed production isn’t possible in this system. It has problems with stability and cannot be used in many mustard lines. If we need hybrid seeds of high purity and improved production, we need a robust pollination control mechanism. A flower has male and female parts. [Mustard self pollinates] and so to make hybrids using different parental lines you need to first make the male plant sterile and in the other parent, you need to put something to restore it, so that the farmer gets fully-fertile seeds. The other aspect is how good the parental lines are. [The controversy over GM mustard] is that we are confusing the two. With the barnase-barstar system (BB system) we can keep on making newer hybrids for traits such as disease resistance and productivity, but the system is basic. Without a good system you can’t have a good hybrid seed production. We started with the observation that combining Indian and East European hybrids are more productive.
What is the difference between a CMS system and a bar-barnase-barstar system?
CMS system is a mutation that occurs naturally in plants or can be induced. It is in the mitochondria (the part of the cell that provides energy) and changes in it can induce sterility. During reproduction the plant needs more energy and the mitochondria (in CMS mutants) tends to fail, during that critical period, in the male part. However for a viable seed generation system this should only work for male sterility, and not affect other parts of the plant. Such mutants are very rare but typically they tend to have side-effects. CMS systems have been worked upon in cotton, chickpea and rice but have had mixed results. China has wonderfully exploited the CMS system for rice but that rice could never grow properly in India. I spent many years (as a scientist at The Energy Resources Institute) trying to improve CMS systems and DMH-1 was a result of that. Sometimes it wasn’t possible to restore the plant’s fecundity; sometimes it would make plants more susceptible to fungus. Finding a perfect CMS is a back breaking job and isn’t like going to a shop and buying it off.
So we thought why not try a barnase-barstar (BB) system. Here genes from soil bacterium (or ‘trans genes’ that don’t naturally occur in a species) are used to induce sterility, and later restore it.
Why is a CMS system more sought after than a BB system?
Because it doesn’t involve trans-genes. For some reason mutations (within a plant), when you don’t know which genes are affected, are considered kosher. But were you to (manually) introduce a gene, even if it’s from a natural plant source, it invites suspicion. That is the mindset under which we are working. The BB system is extremely well understood. It is one of the most brilliant pieces of R&D in plant biotechnology. We thought we should adopt it for our purposes. We know that combining particular cultivars (Indian with East European ones) could give high yielding seeds, we have a method for transforming these genes, and we knew that these genes aren’t patented in India. Our aim was that farmers should benefit from this approach. We have over the years improved this basic science and got European and American patents on aspects such as improving the male sterile lines, restoring them, etc. The patents were not for selling but just to see if the world recognises this technology upgradation. And it has. The basis of this idea has been used to improve European rapeseed and now we have upgraded it to work on mustard.
But groups say that there are already mustard lines that outyield DMH-11?
Complete lies. Why don’t they give a graph? Publish a peer-reviewed paper? All work done in ICAR is recorded and reported, and if it’s good enough, published in peer-reviewed journals. The first trials of DMH-11 were done in 2010. That time Varuna (one of its parental lines) was the national check (a standard practice in India’s agriculture system whereby certain cultivars are designated regional benchmarks). Later on, a variety called Kranti was discovered to yield more, and became the national check. We had started with Varuna and so stuck with it. The suggestion to use Varuna came from the ICAR system itself. To get an understanding of a seed’s yield from independent trials you must compare their trends, or their year-on-year profile. What we have to see is whether the hybrids are consistently yielding more than their parents. Like, for instance, is DMH-11 yielding more than Varuna? DMH-11 has the same male parent as DMH-1 (an East-European line called EH2). Only the female parent is different. DMH-11 uses transgenic technology, DMH-1 uses CMS, and for DMH-11 we used Varuna as the female. The fundamental insight is that you will get heterosis (or high-yielding hybrids) only if you cross an East European line with an Indian pure (cultivar) line. Indian-Indian crossings won’t have that effect irrespective of what technology you use.
DMH-1, that you made in 2002 and made with non-transgenic methods, out-yielded the Kranti and Varuna benchmarks. So why can’t we stick with it?
As scientists, we know DMH-1 won’t go far. Eventually [over generations] sterility breaks down, hybrid seed production is difficult. DMH-11 (that uses transgenic technology) is better to help us have a system to march forward (while producing different varieties of mustard). If people fail to understand this logic, there is nothing much I can do. Activists have gone to such a crude extent of combining the data of different, incomparable trials. That’s not done and is like the earlier instance of comparing the yield of Canadian rapeseed variety with the European ones. Both Europeans and Canadians have done wonderful breeding in rapeseed. We are the ones lagging behind. That somehow doesn’t seem to concern critics.
But are the yields of the European lines higher than our Indian mustard varieties?
They are. Indian mustard [which is in the same taxonomic family as rapeseed] is a 135-day winter crop and grown in a completely different ecology. If you grow European rapeseed here, you will get nothing. Rapeseed has a very narrow genetic base but, as far as mustard goes, we are fortunate to have a wide variety of cultivars. East European, Chinese… in fact [in our lab] we have crossed the Indian and Chinese types and it’s given us new variations that are mind-boggling. But before we utilise it and make new hybrids, there is no point in my claiming them to be wonders. We need to get at this small wonder (DMH-11) first. In general, DMH-11 generally yields 20%-30% more than its parents. Hybrids are more productive than their pure-line parents. That’s what really matters and that’s all that we claim. BB systems are stable and CMS-based systems are a scientific dead-end.
But all the European rapeseeds are based on CMS systems. Is it a global, scientific consensus that an excellent CMS system is better than a stable BB system?
The European hybrids have been developed over 30 years and they have perfected it. Moreover, it’s a choice that Europe has decided not to grow transgenics. It may be a political decision based on public sentiment. Europe is a huge importer of food. Europe doesn’t follow organic agriculture but precision agriculture. They prescribe around 10 different herbicide-combinations that farmers need to spray for those high yields [in rapeseed]. Europe excels in agrochemicals… Bayer, Syngenta, BASF are the top companies in chemistry and making molecules for pesticides, fungicides. They have chosen that path.
Are transgenic seed systems avoidable?
My point is simple. What exactly bothers critics of genetic engineering? Is it because it appears unnatural? Is it because someone is paying you to campaign against it or, is it because you believe agriculture ought to be done the way it was before the 1900s? Before nitrogenous fertilisers all agriculture was organic. This mindset bothers me a lot because it’s misleading and irrational. Every country ought follow its own, rational path. Europe doesn’t need transgenics because they don’t want to increase their area for cultivation. They don’t want to export food. They don’t have 48% of their population dependent on farming. There is, for instance, no organic cultivation in Germany. Are any of their prescribed herbicidal chemicals any less toxic? They are not desperate but India has to be because our yields are stagnating, farm incomes are not growing and we are importing ₹65,000 crore worth of edible oil.
Several European agrochemical companies have bought American seed companies. Bayer’s recent acquisition of Monsanto, for instance.
Very audacious move. China has bought Syngenta, and in one go, they have all of Syngenta’s germplasm as well as agrochemical expertise. China, like India, has been making agriculture-chemicals through generics. New molecule discovery doesn’t exist in India. We don’t want to find new, more benign agrochemicals, we don’t want genetic engineering and we slam our plant breeders. So what exactly is Indian agriculture aiming for?
Why does your plant have a third gene ‘bar’ that’s known to promote herbicide tolerance?
It’s not designed for that. That gene is required to mark out the seeds that have all the desired characteristics after the hybrid crosses are done. This is done at the lab level and doesn’t need to be sprayed by farmers in the field.
Do you think there is a false opposition between GM seeds and organic agriculture, given that the aims of both are to use minimal, chemical pesticide?
Absolutely. There’s a vested interest though I don’t know whose. Take DMH-11. It yields 25% more than the best varieties. If you want to grow it using organic practices, go ahead. There’s nothing inherently contradictory but then you must also evaluate the yields of plants grown this way. There are barely 0.6 million hectares of organic agriculture in the world. Europe might use fungicides for its own purposes but tells India, “Give us organic tea and coffee. We’ll pay you a little more money.” But they wouldn’t themselves grow anything organic. In 2010, according to the Food and Agricultural Organisation, Germany had 11.8 million ha under crops, India had 165.5 million ha, though that may be a slight underestimate. Now look at the insecticide use: Germany [uses] about 1,243.79 tonnes and India about 20,000 tonnes. Fungicides: Germany 9,670 tonnes, India 13,000 tonnes. But Germany’s per-unit consumption of the latter dwarfs India’s.
Can mindsets be easily changed? Many believe that Europe pays a premium for organic food and Indian farmers would do well cultivating it?
And in the process starve our own children? Organic farming is flawed because it’s low-yielding and may not be a problem for us urban folk but will massively hurt our average farmer. If our government says no to technology, it will be a disastrous decision and history will not forgive us for it.
GM Mustard is now in a similar situation to what Bt Brinjal was, about a decade ago. It’s been cleared by scientific groups but awaits a nod from the Environment Minister. Are you worried mustard may go the Bt Brinjal way?
I didn’t closely follow what was happening then. But the fact is that it was a good material and brinjal requires several toxic sprays. I believe it should’ve been taken through. However, every development has its own context, positives and negatives. In mustard, we’ve taken it slow. I don’t see what the environmental problem is anyway. The mustard oil doesn’t contain any protein. The barnase and barstar genes don’t express in the seed, only the bar gene does, to some extent but it poses no threat. There are, naturally, 80,000 proteins in mustard. Some expressed in abnormal quantities may be toxic but we don’t need to go as far as that. There are recommended tests and we’ve done them. That should be the end of it. I do get the sense that higher political class is committed to research and innovation. So let’s see.
There’s another concern. That once GM mustard is cleared it will open the way for other GM seeds that are protected by patents of multinational seed companies. The Indian farmer will thus be beholden to MNCs.
This is the most defeatist attitude one can have. These were the arguments during the Green Revolution, that we are opening the door to international fertiliser companies but we have subsequently built our own fertiliser companies. We have 102 agricultural institutes, 76 agricultural universities. Why have you created them? Shut them down, or recharge some of them and back the good horses.
We have been able to do our mustard work because we were backed by the National Dairy Development Board and the Department of Biotechnology. This, in spite of being based in a liberal university. That shows you the possibilities. When people say that GM seeds could breed monopolies, what is your response? Fight them or keep your farmers stuck to low-yielding varieties and have them importing [oil]. Either way, your money is going to go… What greater crisis do you want in our agriculture? Yields are stagnant, climate change will give you more insect attacks, and we are importing crores worth of edible oil. How will you go about doubling farmers’ income? And all we talk about is GM, GM, GM.
Why do you think transgenic technology evokes such apprehension?
There is certainly a fear. We understand technology as long as it deals with objects of pleasure such as cellphones and cars. We understand health tech but don’t always understand the extent of scientific work underlying it. However, the knowledge of how the world feeds itself is, somehow, extremely limited. Else these paranoid questions wouldn’t be asked. Just as people have health problems, crops have diseases and manipulating genes is necessary to address them.
You say that your BB system is a platform technology and not, on its own, responsible for increasing yields. How do you explain that to farmers?
These mustard plants we have made will spread in no time. Farmers don’t care about underlying technology, and historically it’s seen that hybrids have always done well. I don’t see this as being any different. However, it will do best in ecologies where it has been tested. There may be differences in output in Rajasthan and Bihar. There is no question of blindly promoting DMH-11 all over the country. Right now we hope to release it in parts of Punjab, Haryana, Rajasthan. We are sure it will do very well in these climates.
Wouldn’t farmers in the east, in Bihar and Jharkhand, hear about DMH-11 and want it for their farms?
They would need different hybrids. Varieties are suited for different climates and disseminating proper information about these aspects is where management comes into play. That is where agricultural extension and honesty is required. With dishonesty, anything will crash. The only thing with science and technology is you can’t b******* for too long and you will be found out.
Source: The Hindu, 7-06-2017
