Tag: Rice

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Asweddumized

As designated rice-editor at the Agricultural Biodiversity Weblog, this clipping from The Nation, a Sri Lankan newspaper, landed on my desk. But I am not sure what to make of it.

Researchers (or farmers?) have discovered a (new?) type of rice that can be vegetatively propagated:

The long Mavee rice plant can be cut in pieces and sown to grow as any normal rice. It took the researchers nearly six years to find the specific qualities in the Mavee cultivation, and those plants that contained this quality were later named as Maha Mavee.

Mavee is a variety, maha means wet season (as opposed to yala, the dry season). And as it grows up to “10 feet during flash floods” (that’s quick!) I suppose it is a ‘deep-water’ or ‘floating’ rice type.

So what? Well, the newspaper calls them miracle plants. According to “attorney-at-law and a renowned environmentalist,” Jagath Gunawardane, this is a big deal:

The discovery of this new method of vegetative propagation is likely to revolutionise the entire industry. The Government now needs to help the farmers maintain this cultivation technique, and also prevent companies from claiming patent rights for this ground breaking breakthrough in the agricultural field.

Presumably because of savings in seed cost. Interesting. But then again there are four or five “miracle rices” discovered every year…

To briefly go off on a tangent in an area that I am not a total dummy about, I recently learned the word “asweddumized.” I came across it in the (English language) agricultural statistics of Sri Lanka. I was told that the word was first introduced in 1958 by S.W.R.D. Bandaranayaike, then the Sri Lankan Prime Minister. It stems from the Sinhala word “aswaddanawa,” meaning converting forest land into cultivatable land that has bunds for retaining either irrigation or rainwater, mainly for rice.

But back to the subject at hand. What do you think the prospects are for Maha Mavee? Are there examples of normally seed propagated crops that become vegetatively propagated? Fruit trees through grafting is one example, but that is for a different reason: the propagation of a particular genotype, rather than saving seeds.

People have tried the opposite with potatoes. It seems obvious: ‘true’ (botanical) potato seed is much cheaper than seed tubers, carries fewer diseases, can be stored, etc. But this has not been very successful. Potato was too variable from seed (which makes it so much fun to try this at home), as quality (uniformity and size) is important in the market, and yields were lower. The International Potato Center (CIP) has worked on these issues, and Hubert Zandstra (a former director of CIP) remains optimistic about these seeds, and particularly about their benefits to poor farmers. He thinks that early ‘bulking’ (the formation of tubers) and apomixis may save the day for true potato seed.

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Biodiversity and rice pests

How should farmers deal with rice pests? Spray? Use resistant varieties? Or rely on bio-control ecosystem services?

Brown Plant Hopper Spraying is what many farmers do, to the detriment of their health and environment. It also makes the pest problem worse. Why? Because pesticides also kill the pests’ natural enemies, such as spiders. So you need to spray again, and again. Until the pests are pesticide resistant. This has led to huge outbreaks of brown plant hopper, like in Indonesia in the 1980s, which only stopped after most pesticides were banned. ((Brown plant hopper image from CSIRO.))

Use host plant resistance is what many researchers say. Sounds simple enough, and now there are GMO approaches to get that in different forms. Nature magazine recently had a piece ((Apologies for a post with many references to articles behind a paywall.)) about GM approaches to get insect resistant rice in China. ((Also see this paper by Huang et al. in Science and the critical responses.))

But not everybody agrees. The problem is that some of the major pests occur in large numbers and rely entirely on rice for their life cycle. Strong evolutionary pressure means that these species tend to quickly overcome host plant resistance. In the Nature article, KL Heong calls pest-resistant GM crops a short-term fix for long-term problems caused by crop monoculture and overuse of broad-spectrum pesticides. “Pests thrive where biodiversity is at peril, instead of genetic engineering, why don’t we engineer the ecology by increasing biodiversity?”

This week, in a letter to the editor of Nature, Settele, Biesmeijer and Bommarco also make a case for ecological engineering: the design and construction of ecosystems.

The nice thing about tropical rice is that there is not that much engineering needed to keep pests under control. This is my understanding of how it works:

  • Rule #1: do not kill the beneficial insects (avoid pesticides).
  • Rule #2: help the beneficial insects. For example, by providing ample organic matter to fields, you increase the population of harmless insects and with that the population of generalist predators (see below).
  • Rule #3, maintain a diverse landscape around the rice fields to support useful insects, such as parasitoids that, as adults, need nectar from flowering plants.

William Settle and colleagues studied rice bugs in Indonesia and summed their findings up like this:

By increasing organic matter in test plots we could boost populations of detritivores and plankton-feeders, and in turn significantly boost the abundance of generalist predators. We also demonstrated the link between early-season natural enemy populations and later-season pest populations by experimentally reducing early-season predator populations with insecticide applications, causing pest populations to resurge later in the season.

Irrigated rice systems support high levels of natural biological control that depends on season long successional processes and interactions among a wide array of species. Our results support the conservation of existing natural biological control through a major reduction in insecticide use, and an increase in habitat heterogeneity.

While it seems obvious that relying on and strengthening ecosystem services is the way to go, this is not what is happening. The brown plant hopper is coming back as a major problem, particularly in Vietnam and China. The response? Breeding & Spray, baby, spray.

It is tricky to generalize about agriculture and pests. There are always exceptions and special circumstances. And what if someone can make a rice plant that is truly immune to stem borers and plant hoppers. Well, some other insects would go after the available resources, but it could certainly be beneficial. Also, the biodiversity of insects in tropical rice fields, such as in Indonesia, is much higher than in China (probably largely because of the general relation between latitude and diversity, but perhaps also because of excessive pesticide use in China). So perhaps biocontrol ecosystem services are not as effective in China as in more tropical areas. We should find out.

And we should get serious about ecological engineering.

And not just in rice. Take this article that appeared in this week’s PNAS. It describes the need for maintaining landscape diversity in the USA, to support aphid control in soybeans by ladybugs.

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SRI: does it work or what?

The System of Rice Intensification (SRI) strikes again, now on Java and Bali:

Farmers across Indonesia have bumper rice harvests thanks to a revolutionary method: 50 percent increase in yield with just one 10th of the seed, virtually no chemical fertilizers and little water.

SRI is a system which consists of transplanting widely spaced very young individual rice plants, using organic fertilizers, and not permanently saturating the fields with water. The method was developed — on the basis of existing farmer practices — by a priest in Madagascar in the 1980s, and it has since found a prophet in Norman Uphoff. It is still used in Madagascar, but mainly by larger farmers, as it is too labor intensive for the smaller farmers (who do the work for the large farmers). Or so I was told when I visited there earlier this year.

The BBC reported a doubling of yields in Nepal. George Bush was briefed about it during his visit to India. Luigi wrote about it a year ago. And now the reports of bumper crops in Indonesia.

All is for the best then? Not really: the whole thing is rather controversial. Tom Sinclair said this about it in 2004:

SRI appears to be only the latest in a family of unconfirmed field observations (UFOs) (…). While there is an abundance of “sightings,” they are anecdotal and reported by people who have minimum understanding of the basic scientific principles being challenged by such reports. In many cases, mysterious circumstances are invoked to explain the miraculous.

In a rather thorough review, in 2006, McDonald, Hobbs and Riha found that it sometimes works (in Madagascar), but that generally yields are 11% lower with SRI, not higher.

What is one to think then? Do newspapers blindly follow NGOs, and do farmers say what is scripted? Another case of overselling? Or is this a true farmer/priest led breakthrough, which scientist at fancy universities and research institutes just do not get?

There certainly has been overselling, with claims of unrealistically high rice yields (e.g., 15 tons per hectare). However, there could be circumstances where SRI does have benefits, for example on some problem soils (with iron toxicity), and perhaps in other low potential situations as well.

When SRI ‘works’, it is hard to know what farmers really did. Perhaps planting density was not quite that low, and organic fertilizer were applied at very high. What is SRI being compared with anyway? A degenerate farm, or a fully optimized ‘modern’ farm?

More field trials are planned. I am not optimisitic, but let’s hope that they will provide some clarity about the conditions under which SRI increases yields (or not). The dispute would be settled, and we’d have more rice for less resources.

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Hybrid rice going south

Hybrid rice has been the dominant form of rice seed in China for a while. It has also been spreading to Vietnam, India, Bangladesh, the Philippines and other places. As you know, seed companies like hybrids because farmers who use them need to buy new seed every year. Farmers like the higher yields. It seems that multinational seed companies are increasing their investments in rice hybrids for Asia. Bayer just announced that is has opened up shop in Suphanburi, a rice growing region north of Bangkok. Thailand is a country hitherto better known for rice quality and exports, than for the use of high yielding varieties. Photo credit: Bayer

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Discourse for dinner

This is not just any blog. It is a local blog. Or at least you could pretend I live in your street, and shop in your mall. Does that makes this post more palatable?

It seems to work that way with food. At least where I come from, a dish that is “from our own garden” is supposed to be of high quality, not a sign of poverty. Chad Nilep, in an elegant post on the Linguistic Anthropology blog reflects on the Japanese preference for “naichimai”, Japanese grown rice ((Ed.: Coincidentally, there’s more on Japanese crops over at Vaviblog today.)):

Thus (I thought to myself this afternoon), while consuming naichimai, Japanese consumers enjoy not only the material element of the rice itself, but also the melancholic discourses of national nostalgia, imagined though they may be.

But you could also imagine that I live in a far and exotic place where we produce and eat food that you can only envy. Europe is full of that tradition: ham and cheese from Parma, bubbly wine from Champagne. You name it.

Ask for the main discourse the next time you are eating out.