Very simply, crop yield is the amount of crops produced per unit space (usually hectare). It is a measure of agricultural productivity.
Crop Yields: An Ongoing Struggle
The human race has obsessed over yields throughout history, and a diverse range of methods have been employed to improve yields. The Ancient Greeks and Romans worshiped deities. The Tiahuanaco culture in Peru created patterned arrays of beds and canals (waru waru) to improve irrigation. Western scientific methods gave us cross-pollination, disease resistant varieties and concepts such as heterosis.
The Four Horsemen of the Apocalypse is a Christian story. One of the horsemen, Famine, threatens to increase the price of grain so that it is unaffordable for the majority. A not-so-unfamiliar worry in the present day. With the world population projected to reach 8.1 billion in the next 8 years, producing enough food for everyone seems like an insurmountable challenge. Currently, we are cultivating approximately 40% of the world’s land. According to the Food and Agriculture Organization of the United Nations (FAO), the agricultural land area will remain relatively unchanged. Therefore, yield improvements from the same amount of land will need to account for 80% of the increase in productivity.
In this article, we will explore some of the innovations that will help us to yield more crops from the same land and, hopefully, to feed the world. `
Out With the Tractors, in With the Drones…
It is fair to say that drones in agriculture have garnered a lot of interest over the past 5 years. PwC values drone-powered solutions in agriculture at $32.4 billion.
Drones give an otherwise inaccessible view of crops from above. With this perspective, infrared imaging can be used to visualize the density of the biomass. This data gives an idea of how healthy the crops are. Agribiotix, a drone-enabled agricultural software company, has put this concept into practice. Drone-acquired images are provided every 3 days by Jamie Dumalski, a Canadian farm operator who manages 35,000 acres of peas, lentils, canola, wheat, barley and soy. Agribiotix then converts these images into a normalized differentiation vegetation index (NDVI).
Last year, the data was used to identify localized aphid outbreaks. Treatment could then be targeted to the problem areas. Dumalski estimated that he saved 17% of his pea crop due to this intervention. This is a nice example of how precision farming can directly prevent yield losses.
Rise of the Robots
You’re probably familiar with the term ‘automation’. It has become a common theme across all labor-intensive industries in recent years. Goldman Sachs predict that the digital agricultural technology market will rise to $240 Billion over the next 5 years. You can see why: automation saves in labor costs, frees the farmer from antisocial hours of work, and potentially increases yields through precision farming.
There are several pilot examples of this move towards automation. Sensors have already been installed at numerous facilities to measure air and soil properties and livestock biometrics. The next stage is to convert this influx of data into actionable instructions. For instance, if the soil is too dry, this information could trigger a water sprayer. This allows precision management of crops; something that cannot be achieved on a large scale by the farmer alone.
SwarmFarm Robotics have developed a robotic machine, the size of a small SUV, which is designed to manage planting, weed and pest control, fertilizer application and harvesting autonomously. These robots are intended to replace tractors, with collision-avoiding and accurate spraying technology. The idea being to create a swarm of robots that can manage large areas of crops in a precise, but thorough way.
A Kyoto-based firm called Spread announced at the start of 2016 that they are developing a fully automated lettuce farm. Seed planting was still to be performed by a person, but everything else was to be automated. Through vertical farming methods, the company currently grows 20,000 lettuce heads per day. With the construction of a new, 4,800 square meter, fully autonomous facility, they are aiming for yields of 80,000 lettuce heads per day. Could vertical farming be part of the solution to creating higher yields from the same land area?
High Throughput Phenotyping
Aside from environmental management, the crops themselves can also be altered to produce higher yields. Plant breeding has been used extensively to develop higher yielding varieties of crops. By measuring the high yielding phenotypes, or the plants with the greatest yields, and connecting this data to the plant genetics, it is possible to significantly increase productivity by growing only the highest yielding varieties.
Phenotyping has historically been a very labor-intensive and slow process, requiring individual measurements of metrics such as plant height. However, this is due to change with the invention of high-throughput phenotyping (HTP) methods. HTP employs sensors to monitor the progress of crops. This provides real-time data on crop growth, over time and across large areas. This is important because many aspects of crop performance and genomics are tied to their environment. For instance, certain alleles or genotypes may perform well in one environment, but not in another. With HTP, the breeder can monitor the environmental conditions, soil conditions, and plant performance, and then correlate these with the genotype of the plant.
Such HTP platforms have already been deployed in wheat. For instance, Senix ToughSonic sensors were used by the Biological Systems Engineering Group at the University of Nebraska in Lincoln. The sensors measured crop canopy height, normalized difference vegetation index (NDVI), temperature, reflectance and RGB color. The researchers found a significant correlation between the use of sensors and crop yields at the end of the season. This means that the sensors could be used effectively for phenotypic selection in plant breeding. In other words, the sensor data could be used to select the highest yielding plants.
Will the Grass Be Greener by 2025?
Agricultural productivity is predicted to increase. The current estimates implicate an increase of 2.6% per annum in global production. The FAO states that production will need to increase by 60% before 2050 in order to meet demand. If we bear in mind that production has already increased by 170% between the 1960s and mid 2000s, this target doesn’t seem so out of reach. As we have discussed here, there are many new technologies that aim to increase crop yields without the need to cultivate more land. In addition to this, actual yields are much lower than the theoretically calculated yields. In the case of cereals, potential production could be increased by 170% over several years.
Although the problem of agricultural production is a long-lived one, it is certainly not a thing of the past. As we enter the age of precision farming and high throughput phenotyping, the outlook is optimistic for increasing crop yields. It is the distribution of these advances to the fast-increasing, developing populations that is likely to be the greatest barrier to feeding the world.
