NIAB - National Institute of Agricultural Botany

Orson's Oracle


Posted on 22/01/2013 by Jim Orson

A blog I wrote last May was titled “Infamy” after the great line for Kenneth Williams in Carry on Cleopatra, “Infamy, infamy, they have all got it in for me”. The blog was about the persecution of glyphosate by the anti-GM movement.

Well, the persecution is unremitting. Perhaps in many ways this could be good news. The protesters have thrown all they can at GM glyphosate tolerant crops and yet the worldwide adoption (excluding Europe!) of this technology increases significantly with each passing year. So now those who oppose it have fixed their sights upon the non-GM part of the issue, the herbicide glyphosate.

It reminds me of the advice given out to Americans and Australians during their gold rushes: the only sure way to make money out of a gold rush is to sell pickaxes.

The constant stream of negative statements appears to be having some effect. Some leading farmers are saying that they want to cut down the use of glyphosate because it reduces soil health and affects biodiversity: both aspects feature strongly in the anti-glyphosate literature.

Personally, I have no objection to cutting down on the reliance on glyphosate, particularly when direct drilling is adopted. This is the arable situation where we would expect herbicide resistance to develop most rapidly, because there is no seed shed in previous years being returned to the soil surface layers by cultivations. Hence, there is no slow down in the process of selecting for resistance.

However, to reduce glyphosate usage based on the evidence presented by the anti-GM movement is another thing. The protesters may be quoting scientific papers, but some of these have been authored by those who appear to share the same view. The recent scandal about GM maize apparently causing cancer seems to come into this category.

The protesters may also be quoting results of experiments done by objective scientists but who espouse their own personal interpretation of the results. An example of the latter is a paper published by a researcher from Rothamsted in the 1970s. In this experiment, a very large population of common couch was treated or not treated with glyphosate shortly before winter wheat was established. The winter wheat got more Take-all where glyphosate was used. The simplistic interpretation is that the glyphosate use was the cause of the additional Take-all. In reality, the researcher proved that the glyphosate killed the couch rhizomes but not the Take-all on the rhizomes so it moved to the wheat.

Finally, the anti-GM lobby may well be quoting the results of good experiments but the treatments are not directly related to what will occur in commercial practice. They may be laboratory based experiments or field experiments that use far higher doses than those used in practice.

Due to the charges made by the protesters, there have been reviews of all the available data on glyphosate. One was written for the US Department of Agriculture which concluded “scientific accounts about increased plant disease and mineral nutrition problems in GR [glyphosate resistant] crops are based on publications from a limited number of researchers. In the context of the entire body of relevant science, the significance of these reports is questionable.”

Another review paper concludes “although some laboratory tests have shown effects on nitrogen-fixing bacteria and soil fungi, effects are typically observed only under artificial laboratory conditions and at glyphosate concentrations well above normal field application rates”.

Finally, a review on the impact of glyphosate on biodiversity concludes “In summary, the literature supports the conclusion that non-target arthropods are at minimal risk from glyphosate and its formulations in offsite areas. Within treated areas, applications of the herbicide can produce changes in species diversity and in population size and structure for beneficial insects through modifications of available food sources and habitat.” 

So, the major impact of glyphosate on biodiversity is that it kills vegetation, i.e. what we use it for in Europe.  When used in GM glyphosate tolerant crops its extra efficacy may have some effect on biodiversity. However, sympathetically managed the opposite could well be true.

The associated issue is, if not glyphosate use in order to kill annual weeds prior to drilling...what do we use? Adopting additional cultivations may have a much more negative impact on the environment and the soil. In Europe the only alternative non-selective herbicides are diquat and glufosinate but neither is as effective as glyphosate on grass weeds. In addition, glufosinate is under risk of withdrawal in Europe because it may exceed some of the hazard criteria that are now being used in the registration process.

Although I will stand accused by some of being a ‘Monsatan lackey' or following my own agenda, I would rather back the views of mainstream science.

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Across the pond

Posted on 22/01/2013 by Patrick Stephenson

Northern Regional Agronomist Patrick Stephenson guest blogs from the US

Patrick StephensonLast week I was in the company of Blaine Viator at the Association of Independent Crop Consultants (AICC) annual conference. Blaine is an independent crop consultant from Louisiana specialising in sugar cane and is the current president of the National Alliance of Independent Crop Consultants (NAICC) in the USA. This week it was my turn to fly to the States to their national meeting. Leaving behind 25 cm of snow and flying to 20°C in Jacksonville Florida was, I must admit, appealing.

I now know a good number of their members so it’s really nice to get back up to speed with farming events in the US. Firstly we dealt with the drought, which in the mid-west was very bad for the second year in a row; however many growers had crop insurance.

On quizzing them about crop insurance I was given an hour long lecture on how this worked which, in short, is private and subsidised central government insurance based on achieving historic yields. Most growers take this out and as a consequence did reasonably well.  America, being huge, had a huge variation in weather last year; Louisiana has an annual average rainfall of 2,470mm (100 inches) but this year that figure was passed by September! Add to this - last week 430mm (17 inches) fell and you start to grasp the variations within the country.

Cotton and sugar have taken big price drops which is bad news for us in the UK as growers are turning to wheat as an alternative crop. The south eastern states below Virginia can grow winter wheat and soya in one year. Winter wheat, which is seen as a cheap crop to grow, is drilled in October harvested in June and then soya is planted for harvest in October. Although yields seldom exceed 5t/ha prices exceeding £200/tonne mean that double cropping with soya bring greater and easier returns than cotton and maize.

US agriculture

Genetically modified (GM) crops cannot be avoided as a topic; largely as I look with envy at the thought of glyphosate-tolerant wheat for black-grass control. Unfortunately that horse has bolted in the States and widespread resistance is common. Multi-stacking genes is the next approach combining 2,4-D resistance with glyphosate resistance. This does have a high cost and many growers believe pre-emergence sprays are a more cost effective option. Sugar cane growers turned down the opportunity to use GM to ensure that European markets remained open. Blaine believes this was certainly the best thing they have done.

Potato production is dominated by McCain, Frito Ley and a huge Canadian starch producing company. They have blocked all GM development due to public perception. This is all well and good, but the Bt Colorado beetle resistant crops required no insecticide in a season compared to weekly sprays in the non-Bt crops. Are the public aware of this? I think not! Blight resistance is a much more difficult beast and although genes are available the consensus is that these will only have a brief shelf life as resistance will develop very quickly.

Sorry but it is back to the conference our American cousins love 7.00 am starts.


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Wrong assumptions?

Posted on 16/01/2013 by Jim Orson

Once the New Year is over, farmers’ thoughts turn to nitrogen applications (amongst many other things). NIAB TAG has become particularly interested in nitrogen dose since the introduction of NVZs, increased nitrogen costs and the full realisation of its environmental impact.

In the first couple of years of cross compliance there were many queries from members on the dose of nitrogen for wheat following oilseed rape. The then RB 209 (7th edition) stated that the dose should be as low as 100 kg N/ha following a dry winter and this was the value used by The Environment Agency inspectors to check compliance with the NVZ regulations.

It was clear to everyone that this recommendation was far too low and that following it would lead to sub-optimal crops and margins. To give The Environment Agency credit, they also soon realised that this recommendation was far too low and their inspectors accepted higher doses where justified.

The most recent (8th) edition of Defra’s RB 209 significantly increased the recommendations for wheat following oilseed rape but the issue rankles with advisers and farmers who still consider them to be too low.

One basic assumption in RB 209 is that 100% of Soil Nitrogen Supply (SNS = Soil Mineral Nitrogen plus N in the crop in February plus any allowance for mineralisation) is used by the crop but only around 60% of the applied fertiliser nitrogen is utilised. There are historical reasons for assuming 100% efficiency of use of SNS. In former years, there was more organic material in soils that would release nitrogen during the season, but those days are long gone. Nowadays the majority of arable land has lower organic matter levels and does not receive organic amendments and manures.

This assumption means that for every additional kg/ha of SNS, the recommended dose of applied nitrogen is reduced by around 1.5 kg/ha. Hence, after crops that may leave higher nitrogen residues, as assumed after oilseed rape, the recommended optimum applied dose for feed wheat is reduced disproportionately.

NIAB TAG approached HGCA with its concerns and they financed two projects on the subject (HGCA Project Report 490 - establishing best practiced for estimation of SNS and HGCA Research Review 58 - SNS testing: practice and intepretation). The field studies concluded that the efficiency of use of SNS is typically much less than 100%. In fact, my analysis of the data generated in the field studies suggests that it is below 50% for long term arable soils that do not receive organic manures or amendments.

This means that instead of reducing the applied N dose by around 1.5 kg/ha for every additional unit of SNS the figure may well be around 0.75 kg/ha. I’ve tried this with a retrospective look at around 70 NIAB TAG nitrogen dose trials in wheat that have taken place over the past 10 years or so. These were all carried out on long-term arable soils where no organic manures or amendments were used.Spreading fertiliser

The conclusions are firstly that the Field Assessment Method in RB 209 provides a more accurate prediction of the economic optimum for feed wheat than using the SNS measurement method. Secondly, the accuracy of predicting the optimum is improved by changing the recommendation tables on the basis of an assumed efficiency of use of SNS of 50% rather than 100%. However, this is still no more accurate than using one fixed amount of nitrogen in all the trials!

The most disturbing element is how bad all the recommendation systems are, only predicting within 50 kg N/ha of the optimum in around 60% of the trials. Obviously, we’re a long way from an accurate prediction system. There may be many explanations for this and perhaps this is a subject for a future blog.

At the moment, we have to be content that progress has been made and I hope that the results of the two HGCA funded projects are incorporated into the next version of RB 209. At least it will allow us to catch up with, amongst others, the Australians and the New Zealanders who have for sometime been assuming an efficiency of use of Soil Mineral Nitrogen of between 30-60%.

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A golden future

Posted on 08/01/2013 by Jim Orson

End of year publications often contain facts and figures to sum up progress (or otherwise) over the previous 12 months. One such figure really surprised me; there has been a 30% fall in fruit and vegetable consumption by lower income families in the UK since 2006, attributed to the recession and rising food prices. This is a shocking figure, especially given the Government’s huge ‘5-a-day’ publicity campaign encouraging the consumption of at least five portions of fruit and veg a day, and let’s hope that this fall can soon be reversed.

I suppose that reduction in a good diet highlights the huge challenge to improve the diet of the world’s population. There are very differing views on how this can be achieved. Greenpeace suggests that the way forward is to change farming by universally adopting small scale ‘ecological’ farming (I assume that this is their description of organic farming). On the other hand, agricultural technologists say that we can increase the dietary value of food through plant breeding and genetic modification.

The clash between these two contrasting views is exemplified by the issue of Golden Rice. This is rice that has been genetically modified to have enhanced vitamin A content, an essential nutrient needed for the visual system, growth, development and a healthy immune system. Everybody needs vitamin A to grow and thrive, particularly mothers and young children. Deficiency can cause blindness and impairs immune system function, increasing the risk of death.Golden Rice

Each year, it’s estimated that 670,000 children under the age of five die from vitamin A deficiency.  It is the number one cause of preventable blindness among children in developing countries – as many as 350,000 go blind every year. The main areas where vitamin A deficiency occurs are the parts of Asia where rice dominates the diet, particularly the Philippines and Bangladesh.

Enhancing the vitamin A content of locally produced rice seems a logical, practical and humane way forward. The anti-GM lobby maintains that this is far too simplistic and the problem can be solved by other means, such as more ecologically-based farming, food supplements and better advice. However, they’ve been saying this since Golden Rice was first bred in 1999 and things don’t seem to be getting any better. 

The fall in fresh fruit and vegetable consumption by low income families in the UK, despite widely promulgated advice to the contrary, only emphasises the problems associated with trying to improve diets. It also seems that many of those who are opposed to Golden Rice have been satisfied with stalling its introduction and have subsequently walked away from the issue.

I am not saying that Golden Rice is the complete answer to vitamin A deficiency in rice-dominated diets but it could make a significant contribution to enhancing such diets. My hope is that those who oppose GM and Golden Rice either accept that the technology may make a real contribution to reducing this huge humanitarian tragedy or that they roll up their sleeves and open their wallets to find a realistic alternative way forward.

Field trials on Golden Rice are now being carried out in Asia by the International Rice Research Institute and the trait is going through the regulatory system. I personally hope that it meets the regulatory requirements and is introduced as soon as possible to see if it can contribute to a reduction in such a preventable form of human misery.

By the way, the reason it is called Golden Rice is that the rice is yellow rather than white. This is because the enhanced vitamin A content is achieved by increasing the beta-carotene content, which is also where carrots get their colour from - hence, the association with carrots and good eyesight.

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I don’t believe it!

Posted on 20/12/2012 by Jim Orson

Jim reaches his half century - the 50th Orson's Oracle

I don’t want to sound like Victor Meldrew but I don’t believe it!  We’d travelled halfway round the world and taken several internal flights around New Zealand and it had all gone like clockwork.  We get back exhausted to King’s Cross and the overhead lines are down in the Hitchin area, arriving back in Cambridge two hours later than we should have.

I went to the very south of NZ’s South Island on one of the internal flights, meeting a farmer with exceptionally high wheat yields but only average yields of oilseed rape. Rape has only been grown there over recent years to supply a bio-diesel plant. The plant is only used to crush oilseeds.

The discrepancy between wheat yields and oilseed rape yields in different countries is intriguing.  The poorer the wheat yields, seemingly the higher the relative yield of oilseed rape. I became aware of this issue when I visited Eastern Europe a few years ago.

In Poland, between 2006 and 2010, the average oilseed rape yield was only 29% lower than that of wheat, with wheat averaging less than 4 t/ha. In the UK and Ireland, we have high average wheat yields with rape yielding around 60% lower. In Germany, wheat yields are not as high as here, averaging 7.5 t/ha, and rape yields are about 50% lower. In the more extreme climates of Canada and Australia, rape yields are only around 30% lower than those of wheat.Oilseed rape

I’m not going to pretend to know all the reasons for this. However, lower wheat yields are often because of drought and/or heat during grain fill. Oilseed rape is earlier maturing and its key yield determining growth stages are earlier in the summer when it is likely to be less hot and dry. I recognise that this is rather simplistic and there could be other explanations.

Whilst flying around New Zealand, I was rather horrified to see the amount of land devoted to so-called lifestyle plots. These comprise a few acres and a very nice modern house. The land is used for horses or trees and does not seem to contribute much to food production. The local farmers are generally against lifestyle plots, unless, of course, they get planning permission for them. I agree that they’re difficult to justify at a time when there is concern over future food supplies.

However, this issue is not confined to New Zealand. Our Peterborough Council wants to cover 99 acres of prime fenland with solar panels. Gone are the days when the Soil Survey graded land ostensibly to ensure that the best land is not used for development. I’d better sign off before the Victor Meldrew part of me comes to the fore.

Best wishes for Christmas and 2013.

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