Page 2 of 4
There are two ways to solve the problems of raising crops. One is to adjust the conditions in which they grow, and the other is to alter the crops themselves, to make them more tolerant of the status quo. In practice, farmers and scientists contrive to do both. In hothouses the environment is adapted minutely to the tenderest plants while at the other extreme, drought-resistant, salt-tolerant, semi-wild fodder plants are expected to make the best of whatever nature may throws at them, on rocky hillsides or in fiercely mineralized desert. Most of the world’s farms and market gardens are a compromise: both the conditions and the crops are modified. But as the climate changes worldwide, soil and water are compromised en masse, and as humanity is obliged to make more and more use of marginal land, it will become less and less feasible to adjust environments on the grand scale. More and more, we will need crops that can thrive in whatever conditions happen to prevail. The world needs new varieties of crops at the best of times: all crops are capable of improvement, and all must adjust to evolving parasites. But in these most changeable and unpredictable times the need for novelty and versatility in all classes of field crops is more urgent than ever before.

Poor farmers will need to retain their tough varieties of sorghum and pigeon peas and will need others that are even tougher. The whole world will require new varieties of wheat and other universal staples that march to new environmental drums, whether that wheat is raised by small farmers a hectare at a time or on the industrial scale, horizon to horizon. We cannot, at this time, predict precisely what will be needed. All we can say for certain is that plant breeding has become one of the world’s outstanding priorities and that, to succeed, farmers and plant breeders at all levels will need all the help they can get. No one can escape the environmental and population pressures faced by the planet.

Individual farms and world agriculture as a whole can be designed in a thousand different ways, from the intensive greenhouse to the one-ox subsistence holding, to the cultivated prairies and factories of agribusiness. Some societies may contrive simply to feed themselves while others may aspire to be breadbaskets for the world (or the universal providers of spices or cut flowers). Whatever route they choose, in whatever economic climate, they all need a constant stream of new possibilities, which crop diversity can help to guarantee.

Though some were skeptical at first, few people now care to deny that the climate is changing and that this change could affect everything we do in a hundred different ways. The general effect is of warming and so, eventually, whole regions that are now cool will become mild, and what is merely warm will become tropical. In general, sea levels will rise and flood coastal plains that now provide some of the world’s most fertile and manageable land. Pests of all kinds will move into higher latitudes, taking their cargoes of plant viruses with them: Colorado beetles, aphids, what you will. It is not clear whether the newly warmed places will be wetter (tending to tropical rain forest) or drier (leaning to desert). There will also be eddies in the general climatic trend: some places will become colder, not least because ocean currents may change direction. The overall prediction is of unpredictability, as the Earth readjusts its balance of thermal energy over decades. Already we are seeing extremes of heat and cold, wind and flood.

For agriculture, the devil may well be in the climatic detail. Future climate may not simply be more extreme than ever before. It will be qualitatively unprecedented. Notably, the crops of higher latitudes gear their lives both to temperature but also to daylength: when the weather is cool, they expect the days to be short, and when it is hot they anticipate very short days, and start to produce their flowers and seed accordingly. When the rules change, our present-day crops could become hopelessly confused. Canada’s wheat is of global significance. How will it respond when faced with the customary northern day-lengths but with novel, Mediterranean temperatures? More dramatically, as the flash floods rise and fall and the hurricanes rage, entire systems of farming may be wiped out overnight.

<-- 1  2  3  4  -->