By 2015 the world population had passed the seven billion mark – and the latest UN forecasts suggest it will exceed nine billion by 2050. While obesity is a very real issue particularly in the richest countries, the need to raise global crop productivity, especially on small-scale farms in developing countries, is evident and urgent.
This need is made more acute by three factors:
The limited or zero availability of new farmland, especially if further deforestation is to be avoided or, better, reversed.
The negative impact of global warming on crop yields, excacerbating desertification and, in some regions, reducing water availability.
The trend towards higher consumption of meat in developing countries as incomes rise.
More controversial is the scope for some types of biofuels to contribute to the struggle against global climate change. Innovative crops that can grow on land too arid for food production are one important possibility.
In recent years the dramatic improvements in crop yields seen over the past 100 years seem to have reached a ceiling. Yet according to both FAO and the World Bank we will need to near double average yields by 2050. Only advanced breeding methods based on the appropriate use of biotechnology offer the prospect of achieving this, alongside other innovative technologies – better biological pest control for field crops, the development of safe and effective plant growth regulators and biostimulants, and precision cultivation methods.
SHL recognises the severe social and political constraints that impede small-scale farmers in most developing countries. Land rights, improved women’s education and legal position, and better rural infrastructure and communications are all essential. The need to develop and make available better crop varieties on fair terms must be seem and pursed in this wider context.
Crop focus
Examples of the crops that SHL is engaged with include:
White lupins: The decline in mixed crop and livestock farming (chiefly because of the technical and economic benefits of specialisation) created a need for new ‘break’ crops in cereal rotations. Suitable break crops can help to maintain soil fertility and curb soil-borne diseases and pests. This explains the rise of oilseed rape (OSR) which can be grown and harvested using the same equipment as for cereals. But OSR is a non-legume and provides low quality protein with a limited market (40% of the UK OSR crop goes for subsidised biodiesel production). Field beans are disease-prone, yield poorly and their feed value is limited. White lupins, in contrast, are excellent for both human and animal nutrition, as good if not better than soya which needs a warmer climate to perform well. And white lupins as a legume fix nitrogen, reducing the need for fertiliser with following crops. But improved ‘sweet’ varieties are needed – with consistent low alkaloids, robust anthracnose resistance and earlier ripening. There is a huge natural diversity of white lupins that could be incorporated into precision breeding programmes and bring benefit to farmers worldwide.
Bananas: This crop is virtually seedless so is near impossible to breed using conventional methods. Large plantations are sprayed by air up to 70 times a year to control devastating fungal diseases such as black sigatoka, typically achieving yields of 45 tonnes/ha or more. Small-scale growers who produce 80 percent of the global crop mostly cannot use sprays effectively and their yields are commonly only a quarter or less of those on plantations. Introducing genes conferring resistance to some of these diseases could drastically improve smallholder yields and subsequent profits while reducing the environmental impact of widespread pesticide use. Advances in tissue culture techniques (enabling combination of different banana germplasms) and transgenic techniques may both have a role to play in producing the varieties with traits so urgently needed.
Potatoes: This is another major crop with severe disease and pest problems usually controlled by heavy pesticide use. The recent widespread bans on the use of nematicides mean that large areas of the best potato-growing soils can no longer be used for the crop because their nematode populations are too high. Conventional breeding methods have developed varieties with good resistance to some diseases such as scab and some resistance to early and late blight – but progress has been slow. Innovative transgenic varieties have robust resistance to late blight and nematodes, offering the opportunity to rapidly incorporate other traits such as drought tolerance, reduced storage losses, better cooking characteristics and improved nutritional content into the most favoured varieties. See www.biopotatoes.com