Half of the world will die!

That’s roughly what Reverend Thomas Malthus predicted some 200 years ago in his Essay on the Principle of Population. Malthus thought war or pestilence would decimate the population from time to time, and if that didn’t happen ‘gigantic inevitable famine stalks’. That’s right; we’re going to starve to death.

Malthus wasn’t a very cheery chap. The good news is that technology made a fool of him. The Rev. Malthus simply didn’t envisage the age of industrial agriculture, when a farmer can harness 60 willing horses with the turn of a key. And he didn’t see the development of Mendelian genetics that has allowed plant breeders to select more productive varieties.

Paul Paynter and Maria-Rosario Germino

They still talk about Malthus in economic classes the world over, on the basis that while his timing was off, his theory could well be right. There must be a limit to the carrying capacity of the earth.

Maybe that limit isn’t that far off. UN estimates we must produce about 40% more food by 2030 or millions will face starvation. Before starvation we’ll likely see food riots and maybe even wars as some consumers get priced out of the market.

At the height of the economic bust in 2008, the price spikes for staple foods caused riots in 17 countries.

It may be that the risk of food shortages is a temporary phenomenon. The rate of population growth is already falling. By 2050 population trends may well level out. As societies in the emerging world become more affluent, couples buy TVs and cut down on the monkey business. Why would any man get a vasectomy when watching golf on TV has the same effect?

In the interim there is a challenge and an enormous opportunity for the farmers of Hawke’s Bay. There is a compelling incentive for us to improve the levels of productivity and sustainability.

Apples, for example

Many pundits expound their visions for farming in woolly and idealistic terms. The truth is you don’t really get to the crux of these issues without examining the issues that confront a specific crop. I’m well positioned to do that for apples, but I’m sure I won’t be popular for ‘lifting the veil’. “Best not talk about these things in public” is the view of many. I disagree. Sunlight is the best disinfectant.

The good news is that apple production has never been as safe and sustainable as it is today. In the latter part of the 1990s the NZ apple industry implemented a system called ‘integrated fruit production’ or IFP. This system is the new ‘conventional production’; a moniker that many growers loath as it grossly undersells their achievements. IFP emphasises, amongst other things, working with nature, monitoring pest life cycles, using pheromone mating disruption and encouraging populations of predator insects.

After a decade of development of IFP, Plant and Food Research revealed that the use of nasty organophosphates was down 98%, fungicides down 42% and herbicides down 50%. Sadly the industry did a terrible job of telling the consumer what had been achieved. ‘We’re spraying much less’ isn’t much of a marketing pitch.

At the same time we saw the rise of organic apple production. I love organics as they captured the imagination of the consumer and ignited environmental consciousness across the growing community.

IFP and organics mostly have pest problems in check. 80% plus of spraying today targets a single disease; the stylishly named Venturia inaequalis, or black spot. This overwhelming dominance of one disease is also seen in other produce like potatoes (Late Blight) or bananas (Black Sigatoka). If only we could overcome black spot we could reduce spraying in apples by that 80% plus.

The only flaw in organics is that it believes that everything natural is good, and everything man-made is bad. On that basis you must approach your car thinking ‘rubber tires … good; plastic steering wheel … bad’. Organic devotees should be much more comfortable with a wooden steering wheel, which is not without its appeal. The truth is that some natural things are lethal and some man-made things are harmless. Fungicides in agriculture were once exclusively organic compounds based on copper, sulphur and, brace yourself, arsenic and mercury.

As things stand today, organics is not the solution. The copper and sulphur compounds still widely used in organics are toxic to many beneficial insects, fungi and bacteria. The sulphur products are the lesser of two evils, but still quite toxic and not very effective. This causes most organic growers to spray 2-3 as often as IFP growers and yields are about 25% less. The organic carbon footprint and level of soil compaction is substantially higher as a result.

The broader environmental effects are also worth considering. Organic compounds mostly come from unsightly open cast mines and are required by growers in much greater quantities. Worst of all, some of these compounds can be quite persistent in the soil. In Britain, organics is managed by the Soil Association and at its core, soil health is the foundation of the organic movement. Current organic apple production methods do not deliver on these values.

Now I’m not saying we shouldn’t grow organically. Organics is well suited to many crops, but for apples it’s a hard road. Our relatively wet and mild climate means Hawke’s Bay has high levels of disease pressure.

Beating black spot

The greatest asset in organics is the dedicated and sincere producers it has. As a sector they recognise the challenges they face and they’re working hard on solutions. For black spot they are experimenting with yucca extracts, antagonistic fungi, and many other strategies. Organics will conquer their challenges eventually. There is no silver bullet though.

The solution to black spot will probably come from plant breeders; in fact it already has. Breeders found that the Japanese flowering crabapple didn’t get black spot and they identified the Vf gene that caused this resistance. A few crosses later and out popped a range of black spot resistant apples. They aren’t world beaters, but decent apples none the less.

The problem was that the Vf gene only created simple, single gene resistance. Over a decade or two new strains of the black spot fungus developed. Basically some black spot became resistant to the resistance.

The war against disease doesn’t have to be a tit for tat battle like this. Breeders these days talk about gene pyramiding and polygenetic resistance – that is the use of multiple genes to create durable resistance to the disease. This isn’t just another pipedream theory.

The spiritual home of apples is the wild apple forests of Kazakhstan. Here in remote and inhospitable mountains 20,000 years of natural selection has occurred and there are varieties that appear entirely resistant to black spot. Over time breeders will manage to incorporate these genes in commercial apple varieties. The only problem is that it will take millions of crosses to achieve the desired combination of both disease-resistant genes and delicious apple genes. I think 30-50 years is a reasonable timeframe for success. Malthusian outcomes are still in play.

There is one other alternative. While you might be terrified about scientists putting a frog gene in your potatoes, how do you feel about them putting the disease-resistant genes from one apple into another? And would it change your perspective if GM could deliver an 80% reduction in organic or IFP fungicide sprays?

The only two options with GM technology are to ban it or proceed with caution. Is limiting GM to within a genus, the ‘proceed with caution’ model? There are 170,000,000 hectares of GM crops now grown and so far the technology looks safer than cars, organ transplants or Coke.

So, now you’re armed with the facts, which strategy should growers pursue? IFP, Organic, or GM?

And which strategy is most likely to keep the apocalyptic theories of Rev. Malthus at bay for another century?

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