A new report commissioned by the British Society of Plant Breeders (BSPB) demonstrates the contribution that the plant breeding sector has made to agricultural sustainability over the last 50 years, and points to its future objectives.
The report is the third commissioned by the Society in recent years. It funded a NIAB study in 2009 that showed how genetic improvement is the primary source of increasing yield in the major arable crops. This was followed in 2010 with an economic analysis by the DTZ consultancy that concluded investment into plant breeding delivers a 40 fold return across the food chain and into the wider British economy.
The latest report, prepared by James Clarke and his ADAS colleagues Rebecca Carter and Steven Tompkins, reviews the contribution of plant breeding to the sustainable intensification process called for by former government chief scientist Sir John Beddington in his influential Foresight Report of 2011.
The Foresight report led the government to review the way it funds food and farming research, leading to the AgriTech Strategy designed to encourage future food security, economic growth and sustainable development. The ADAS review set out to assess the extent to which the objectives of plant breeding for the major UK combinable crops, forage maize and sugar beet are commensurate with the sustainability goals.
Yield and crop quality have increased over recent years. ADAS data measures a 0.5tonne/ha increase per decade in Recommended List work since 1970. Although the gap between trial and actual farm yields has widened in the last 15 years for a number of reasons, the trial yields show this level of output is possible and can be aimed for on-farm, comments Mr Clarke.
Similarly, RL work over the years shows increases in quality attributes such as wheat protein contents; cereal disease resistance – particularly fusarium, eyespot and yellow rust - and resistance to pests - notably Orange Wheat Blossom Midge. Commercially, pests are less of a problem in the Northern Hemisphere than plant disease, and this factor, coupled with relatively cheap insecticides, means there has been less investment in insect resistance through plant breeding.
Turning to plant nutrition, the increase in wheat yields over the last 35 years has been faster that the rate of N fertiliser applications which have remained stable in the same period, showing a rise in the efficiency of resource use and less harmful emissions. Genomic progress has identified genes with a link to nitrogen efficiency, and these traits can be further exploited by plant breeders as knowledge in this area advances.
When it comes to reducing environmental impact, plant breeding can help with more efficient water use, and in protecting soil health by encouraging rooting development in crop plants to enable lower input applications, which in turn reduces potential for water contamination, while better rooting improves soil structure and health.
In conclusion, plant breeders have proved adept at increasing yield (with the exception perhaps of pulse crops), quality attributes and plant disease resistance over the last 50 years, says Mr Clarke. However, there is more development work required in developing pest resistance and in breeding crop varieties that are adapted to the more extreme environments that are predicted as a result of climate change.
Plant breeding has therefore been a major contributor to meeting the goals of sustainability across multiple objectives, he states. The focus on raising yield through better genetics also delivers measurable benefits to resource efficiency and the environment by reducing unit demand and resource wastage.
For the future, the plant breeding sector can continue to deliver commercial varieties with an emphasis on better nutrient and water use, higher photosynthetic efficiency and more robust climate resilience.