Oct. 25, 2016
To meet the food supply needs of the world's growing population, global food production will need to roughly double by 2050. Every day, the world population increases by ~200,000 people. We need to increase crop yields even as we face new environmental challenges, like weather extremes.
Scientists are battling the threat of climate change, which causes erratic weather patterns and global warming, projecting that for each 1° Celsius increase in global mean temperature, wheat yields may decline by 6 percent. Cereal production is increasing worldwide but current rates of yield growth are not sufficient to satisfy future demand, even without climate change factored in. We can’t create more land or strong arm the weather, so how are we going to accomplish the huge task of feeding everyone?
World-wide, crop yields are affected by several abiotic and biotic stress factors leading to yield gaps. Innovation in plant science and agriculture is the key to closing the yield gap, and I get excited seeing all the progress that’s been made in agronomic, engineering and chemical technologies to improve yields in conjunction with genetic technologies.
Longer term genetic advances must be anticipated and enabled by other crop enhancement technologies, so that potential synergies are properly developed and exploited. For me, this is how we will realize the potential yield of every seed – but this will require some ‘joined-up’ thinking.
Major possibilities in wheat… 15t/ha by 2050?
The basic plant physiological processes involved in crop production are very similar in all the staple crops – rice, wheat, maize, potato, etc. – which are short-term mono and dicot annuals, or have C3 or C4 photosynthesis. Here, for simplicity and its importance as a food source, wheat is taken as an example.
Physiological analysis shows that wheat yields could potentially double to ~15 t/ha, from the current UK farm average of 8 t/ha. While plant breeders continue to improve wheat yields by 0.5 t/ha/decade, there has been no on-farm yield improvement beyond 8 t/ha for the last 15 years. Hence there is an immediate need to realize existing genetic potential.
The rate of wheat yield progress will depend on innovations to: (i) prolong the crop’s yield-forming period, (ii) optimize its water and nutrient use efficiency, (iii) mitigate the effects of heat stress, (iv) improve its photosynthetic efficiency and carbon allocation and (v) protect yield-formation from disease, pest and weed pressure. However, yields could actually decline if the rate of evolution of resistant pests, pathogens and weeds outstrips the rate of introduction of new genetic, agronomic and chemical technologies.
With year-on-year genetic gains beginning to peter out, the race is on to find step-change technologies to realize the genetic potential of each seed. Sophisticated methods, like molecular breeding, seed chipping, the use of seed and foliar applied crop enhancement treatments and emerging powerful techniques like gene editing can offer a lot of improvements to the crops farmers grow and the downstream benefits to all of us as consumers.
Technologies such as seed chipping and whole genome sequencing are enabling plant breeders to look closely at the DNA of each plant and predict performance before the seed even gets planted in the ground. Using location-specific information about soil nutrients, moisture and productivity of the previous year, new tools known as “variable rate application” can put fertilizer only on those areas of the field that need it. We’re at the cusp of this next wave of innovation in digital agriculture, as modern computer vision, precision sensors, and machine-learning technology help farmers use last century’s advances more efficiently and precisely to enhance productivity. And, by adopting integrated technologies, the inherent yield potential of each seed planted would be realized along the way.