Changing How Plants Grow
Mar 29, 2018
Agricultural scientists have been studying how plants grow and reproduce for hundreds of years, with the first systematic insights on the genetics of plants coming from Gregor Mendel, an Augustinian monk from Brno in the Austro-Hungarian Empire (now part of the Czech Republic). Mendel described the basic principles of genetic inheritance based on his study of pea plants in the mid-19th century. Dr. Norman Borlaug took that work to a higher level in the 1960’s with his use of shuttle breeding across different climatic zones to accelerate his efforts to develop higher-yielding wheat varieties as a scientist for the International Wheat and Maize Research Center (CIMMYT) in Mexico. Borlaug was awarded the Nobel Peace Prize for his work in spurring the Green Revolution in 1970.
Plant breeding took another quantum leap with the emergence of genetic engineering techniques in the mid-1990’s, with the first commercial GM crop being released, the Flavr Savr tomato, in 1994. This fresh tomato was designed to have a longer shelf life than its conventional counterparts, but unfortunately, its developers forgot to pay attention to whether or not the tomato tasted good. It was withdrawn from the market within a few years.
The first successful GM product was BT corn released in 1996. This product was developed by inserting genetic material into corn seed designed to create resistance to specific pests that were economically harmful to corn farmers, such as the European corn borer. This trait is still available in corn seeds planted across the world, though now it is most commonly sold in seed that incorporate mutliple GM traits such as resistance to various kinds of herbicides such as glyphosate (commercial name Roundup). There are currently 16 different crops with GM traits available for cultivation around the world, although the largest in terms of total acreage are corn, soybeans, and cotton.
Utilizing the extensive knowledge of plant genetics that emerged from mapping the genomes of major crops for agricultural biotechnology efforts, conventional plant breeders have been able to more precisely target the traits they want to emphasize, a process called marker assisted breeding. Scientists developing crops using both genetic engineering and conventional breeding techniques have both benefited by the explosion of available data and computer technology capable of handling large quantities of data in modeling their new ideas long before a single seed is planted in the ground.
In the last few years, a more targeted way of developing new traits in crops and animals has become widely utilized, known as gene editing. These techniques allow scientists to turn on or off genes that already exist within a given organism, rather than inserting a gene from an outside source (such as from the bacillus thuringensis (BT) bacterium to create a novel trait. On March 28th, USDA announced its determination that gene-edited crops would not be subjected to the requirements of its biotech regulations, unless the trait being added deals with pest resistance.
All these new tools have enabled scientists to start looking at ways to improve the fundamental efficiency of how plants grow. For example, a team of scientists at the University of Illinois began working in 2012, seeking ways to improve the photosynthesis process in plants, ie.,the conversion of sunlight, water, and nutrients into plant matter. The early work on tobacco plants was funded by a $25 million grant from the Bill and Melinda Gates Foundation, followed up last year with a new grant, funded by the Foundation for Food and Agriculture Research, the U.K. Department for International Development (DFID), as well as the Gates Foundation. In addition to the University of Illinois, scientists from two U.K. universities (Essex and Lancaster), one Australian university (Australian National University), the Commonwealth Science and Industrial Research Organization (CSIRO) in Australia, the Chinese Academy of Sciences, two other U.S. universities (U.C.-Berkeley and Louisiana State University), and USDA’s Agricultural Research Service are involved in the research. The new funding has allowed expansion of the research into food crops such as soybeans, cassava, and cowpeas, the latter two especially important for smallholder farmers in developing countries.
Similarly, scientists at the Danforth Plant Science Center in St. Louis and collaborators at Louisiana State, USDA, and the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) in India late last year announced a breakthrough in their work to suppress emergence of the aflatoxin fungus in peanuts, or groundnuts as they are known outside the United States.
Last month, scientists at the Cold Spring Harbor Laboratory in upstate New York announced advancement in work to modify the sorghum plant to produce more flowers as it matures, thus potentially tripling the grain yield from the plant at harvest.
With the need to produce between 50 and 70 percent more food by 2050 to feed a projected global population of 9.7 billion people, in an environment with constrained availability of arable land and water, all this work improving crop productivity will be needed, and then some.