Healthy soil and sustainable growing

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On 9/14/2004 at 12:46 PM press-release@i-sis.org.uk 
<press-release@i-sis.org.uk> wrote:

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>ISIS Press Release 14/09/04
>
>Non-GM Iron Rice a Solution?
>*********************
>
>
>Is genetic engineering necessary to develop rice rich in
>iron? Lim Li Ching reports on successes achieved with
>conventional breeding.
>
>
>Sources http://www.i-sis.org.uk/full/NGMIRASFull.php
>for this article are posted on ISIS members' website.
>Details here http://www.i-sis.org.uk/membership.php.
>
>Iron deficieny
>
>Iron deficiency is the most common of all nutritional
>deficiencies. Approximately 3.7 billion people suffer from
>this condition, and it is most widespread in children and
>lactating mothers. Iron deficiency leads to anaemia;
>overall, 39% of pre-school children and 52% of pregnant
>women are anaemic, of whom more than 90% live in developing
>countries.
>
>Anaemia is bad for health and development. In infants and
>young children, it impairs growth, cognitive development and
>immunity; at school age it affects school performance and
>reduces activity levels; at adulthood it reduces work
>capacity and lowers resistance to fatigue. In pregnant
>women, it is linked with an increased risk of maternal
>mortality and illness, as well as an increased risk of pre-
>term delivery, retarded foetal growth, low birth weight and
>foetal death soon after birth.
>
>Iron tablets are a possible solution, but require a
>continuous supply and can cause side effects. In the long
>term, ensuring adequate iron intake through food is viewed
>as the best option. For most populations, the best sources
>of iron are meat products, but these are relatively
>expensive and little consumed by the poor.
>
>Conventionally bred 'biofortified' rice
>
>Rice, the staple diet of millions in the developing world,
>is a poor source of micronutrients. Where rice is the
>staple, about two billion people suffer from iron-deficiency
>anaemia. Efforts have thus focussed on 'biofortifying' rice
>to make it nutritionally better. Genetically engineering
>rice to increase its iron content has been one course of
>action (see "Rice in Asia: Too little iron, too much
>arsenic", this series
>http://www.i-sis.org.uk/RIATLITMA.php).
>
>But is genetic engineering needed to develop iron-rich rice?
>There are already successes reported in naturally breeding
>and selecting rice with high iron content, which would not
>carry the risks associated with genetic engineering.
>
>Plant breeders at the Philippines-based International Rice
>Research Institute (IRRI) have identified rice varieties
>that are naturally high in iron. They screened nearly 7 000
>samples of rice germplasm stored in the IRRI gene bank, for
>high iron and zinc content. Of these, 1 138 samples were
>grown. They found that aromatic grains were usually higher
>in iron concentration and often also higher in zinc,
>compared to non-aromatic varieties. Data from various
>studies demonstrated that high iron and high zinc traits
>were generally expressed in all rice environments tested.
>
>IRRI at the same time was trying to grow, by conventional
>breeding, new varieties that could thrive in poor soils and
>cold temperatures. "Quite by chance, it was discovered that
>one of the varieties designed to tolerate low temperatures
>had also inherited a richness in iron and zinc from one of
>its parents," explains IRRI scientist Dr. Glenn Gregorio.
>
>This aromatic variety is a cross between a high-yielding
>variety and a traditional variety from India, from which
>IRRI identified an improved line (IR68144-3B-2-2-3) with
>high iron concentration. The grain has 21 parts per million
>(mg/kg) of iron, about double the normal content in rice,
>and also about 34 parts per million of zinc.
>
>Research has shown that high zinc and iron densities are
>positively correlated. Zinc may enhance the body's capacity
>to absorb iron. It is essential for a healthy immune system.
>Zinc deficiency in children is also associated with poor
>growth, reduced motor and cognitive development, and
>increased infectious diseases. It is linked to pregnancy and
>childbirth complications, lower birth weight and other
>foetal effects lasting through childhood. Moreover, high
>zinc density is good for seedling vigour, improving plant
>yields. IR68144 is also reported to have a high content of
>Vitamin A.
>
>"Almost as a bonus, it had good flavour, texture, and
>cooking qualities. And, to please the farmers, it was also
>high-yielding." This bodes well, for adding new traits can
>sometimes have a general negative effect on yield. The rice
>also has good tolerance to rice tungro virus and to mineral-
>deficient soils. All these factors are important for
>maintaining crop productivity and consumer acceptance,
>crucial to ensure that new varieties sustain farmers'
>incomes.
>
>Trials establish that iron is absorbed
>
>Does the increased iron content translate into improved iron
>status in the consumer? After 15 minutes of polishing,
>scientists found that IR68144 had approximately 80% more
>iron than a popular but low-iron commercial variety.
>Research conducted at Cornell University showed that the
>iron in IR68144 polished rice was absorbed by laboratory
>rats, and by human colon cells in culture.
>
>"Then we fed some other high-iron varieties experimentally
>to a family of two parents and four children living near
>IRRI's headquarters in the Philippine province of Laguna,"
>Dr. Gregorio said. "All but the father were mildly anaemic.
>After the family members ate the enriched rice for two
>months, however, their serum ferritin levels rose
>dramatically, to the point where the lowest of them was
>double the level recommended for good health."
>
>In 1999, a trial was carried out on 27 women in the
>Philippines, who ate IR68144 exclusively over six months.
>The volunteers - sisters at a Roman Catholic convent - had
>their food measured, their activity monitored and body
>weight noted. Once a month, their blood was tested. The
>sisters were selected because they represent a sex and age
>segment of the population at high risk of iron deficiency.
>
>Most of the sisters, aged between 20 and 30 years old, were
>mildly anaemic while on their normal diet of rice purchased
>from the market. 74% were anaemic (haemoglobin <120 g/L) and
>48% were iron-deficient (serum ferritin <12 µg/L). But,
>after eating IR68144, the serum ferritin (an iron storage
>protein) levels in their blood increased - in many instances
>two or three times higher. In some cases, this was
>sufficient to raise their iron levels from deficient to
>above average.
>
>A much larger and carefully structured clinical trial,
>involving 300 sisters from eight convents around Manila
>concluded in September 2003. In one of the largest human
>feeding trials of a staple food, each sister was randomly
>assigned to receive either regular (low-iron) rice or the
>high-iron variety. The sisters and the research team were
>not told what they were receiving during the trial. The food
>was cooked in a common kitchen and consumed in a common
>dining room, so the distribution and consumption of
>different rice varieties could be carefully monitored.
>
>The sisters' iron status, as shown by haemoglobin and other
>biochemical indicators, was measured before the trial began,
>halfway (4.5 months) and at the conclusion (9 months). Women
>remaining - or newly - iron-deficient at the end of the
>trial were given iron supplements to ensure this deficiency
>was corrected. The trial also examined the interplay of
>minerals and nutrients within the body to look at their
>interactions, and observed the sisters' cognitive functions
>and capacity to concentrate.
>
>Preliminary analysis of the data indicates positive results.
>There was modest improvement in blood iron levels, showing
>that iron in rice endosperm is absorbed by the body. Among
>the women who were iron-deficient but not yet anaemic at the
>start of the trial, total body iron reserves improved
>significantly. The women who consumed high-iron rice took in
>about 20% more iron per day than those who ate regular rice,
>and increased their body iron by 10%, while the women
>consuming control rice actually lost 6% of their body iron.
>The greatest increases in body iron were seen in the women
>who consumed the most iron from biofortified rice. The
>results of the study are being published.
>
>Future scenarios
>
>The next step would be to conduct trials on the effect and
>use of high-iron rice in a community setting and on the
>effect on children's iron status. A study is planned in
>Bangladesh in 2004-2005. If successful, IR68144 seeds will
>be given to agricultural research organizations in various
>countries for adaptability testing and to begin
>crossbreeding for pest and disease resistance as well as
>hardiness for local conditions.
>
>IR68144 or its offspring could then be released to farmers
>in developing countries, for free, in two or three years.
>Meanwhile, IRRI's search continues, among the 26 000 samples
>of rice varieties it holds in trust for humankind. Dr.
>Gregorio is sure that a new variety could be bred with even
>higher iron content. IR68144 could be the first of several
>traditional rice varieties found to be nutritionally richer
>than previously thought.
>
>Already, recent reports indicate that Thailand's Department
>of Agriculture has identified two rice strains - selected
>from 45 strains of Thai rice - that can accumulate iron.
>Korkhor 23 has an iron content of 36.67 parts per million
>(ppm) when unpolished, reduced to 22.5ppm when polished.
>Unpolished Khao Hom Phitsanulok 1 rice has an iron content
>of 25ppm, compared with 22.5ppm in it polished state. Rice
>grown in different areas have different rates of iron
>accumulation. Research continues to find better iron-
>accumulating strains, and to determine the best growing and
>milling techniques to preserve iron in the rice. However,
>Dr. Laddawal Kannanut of the Rice Research Institute was
>quoted as saying that genetic engineering would be used to
>improve the strains' ability to accumulate iron.
>
>This is unnecessary, for as the IRRI research shows,
>conventional breeding can successfully develop high-iron
>rice that is both high yielding and disease resistant.
>Conventional breeding works because iron occurs naturally in
>rice grains and the high variability in the grain iron
>content allows selection of high-iron parents for
>crossbreeding. Moreover, farmers will grow the iron-dense
>rice because its high-yielding characteristic makes it
>profitable to do so. And, trace minerals such as iron are
>undetected by the human eye and thus do not affect
>consumer's preference.
>
>In future, it won't be just rice that is targeted for
>biofortification. Significant funding has been committed to
>develop biofortified crops. The IR68144 research is now part
>of a larger initiative by the Consultative Group on
>International Agricultural Research (CGIAR) and its research
>centres worldwide, coordinated by the International Food
>Policy Research Institute (IPFRI). In October 2003, the
>Gates Foundation committed $25 million to this initiative,
>HarvestPlus, which aims to develop crops with enhanced
>nutrient status: not just with iron but also with vitamin A
>and zinc and in other key staple crops important to the poor
>(wheat, maize, beans, cassava, and sweet potato).
>
>The danger is that the efforts will focus on genetic
>engineering, at the expense of safer alternatives. For
>example, IRRI claims that for vitamin A enhancement, genetic
>engineering is needed, as vitamin A does not occur naturally
>in rice grains. In 1999, Swiss scientists successfully
>expressed vitamin A in transgenic rice grains - the so-
>called 'Golden Rice'. IRRI is now incorporating the vitamin
>A genes into high yielding varieties.
>
>Biofortifying food crops, even by means of conventional
>breeding, must not replace other interventions such as
>diversifying diets, conventional fortification and
>supplementation. Efforts to enhance the iron content of rice
>must also be mindful of the interaction between iron and
>arsenic, a particular problem for the arsenic-contaminated
>paddy fields of Asia (see "Rice in Asia: Too little iron,
>too much arsenic", this series
>http://www.i-sis.org.uk/RIATLITMA.php).
>In addition, in areas where iron intake is high, iron
>overload can become a real problem.
>
>The need for biofortification today is largely due to the
>mistakes of the past. For example Green Revolution methods
>have mined the soil of nutrients and monocultures have
>resulted in the loss of diverse traditional varieties.
>Alternative food sources rich in iron should be promoted, as
>should diverse cropping and sustainable agriculture. This
>could prove to be a much more sustainable strategy in
>addressing iron deficiency.
>
>
>========================================================
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