Researchers in Australia first began looking at a new technique called speed breeding eight years ago, and U.S. researchers have followed suit with their own trial projects in recent years.
The concept involves exposing plants to an inordinate amount of light in a close greenhouse environment in an effort to speed up the growing process and produce new generations of seeds in a much quicker fashion. The initial research in Australia involved wheat but there have also been some efforts to apply the new technique to vegetables and other crops.
Stephanie Sjoberg, a PhD candidate in plant breeding in the Crop & Soil Science Department at Washington State University, is one U.S. researcher working on the idea. She is currently working on wheat and came to WSU in 2016 to pursue this line of research. Previously she was in the vegetable seed industry with Bayer for a half a dozen years and also worked for H.M. Clause and Monsanto. Her career is in plant breeding and admits that her current work with wheat revolves around the fact that it is a major agronomic crop and there is available funding for such crops.
She said the speed breeding work in Australia is very interesting, the concept is well known among the plant breeding community, and she believes there is applicability for a variety of crops, noting that work has been done on wheat, barley, canola, chickpeas and brassicas among others. Sjoberg believes the tomato would be a good candidate as well. She explained that the concept involves exposing a plant to 22 hours of artificial light and two hours of dark. “That technique has significantly sped up the life cycle of production,” she said.
In Australia, researchers have been able to produce six generations of wheat plants per year as opposed to one annual crop in the field and two or three under normal greenhouse conditions. This technique allows for much quicker development of new varieties with positive traits being bred into the plants in a much quicker fashion. Sjoberg said the research has shown that the speeding of the plants production has no adverse effect on the development of the seeds being produced about every six weeks or so. She did say that this technique would not work when actually trying to produce a fruit or a vegetable as the passage of a time in a plant’s normal growth is needed to grow a crop to fruition, but harvesting seeds has proven to be a different matter.
The importance cannot be overstated as it typically takes five or six generations of plant breeding to develop new parental lines to produce seeds with the new positive traits that a producer would be looking for. If those parental lines can be produced in one year rather than five or six the advantages are obvious. Sjoberg said the development of the speed breeding work across many different plant lines will have a “huge impact” on the industry. She said it has the promise of cutting new variety development time in half or less.
Of course, speeding up the development of new varieties has been an elusive goal of plant breeders for many, many years. Biotechnology and work at the gene level has promise and has led to the use of “markers” to identify and transfer positive traits easier and more quickly. Sjoberg said genetic sequencing allows researcher to detect genes linked to markers and transfer these traits between varieties without going through the entire time-consuming, plant-breeding process. For example, there is a determinate and indeterminate gene in tomatoes that are utilized for production of varieties based on whether they are developed for fresh or processed production. A bush or processed tomato variety will have the determinate gene, which means it will grow to a specific size for the goal of achieving a uniform, one time harvest. A fresh market tomato variety will include the indeterminate gene, which allows it to continue to grow and produce marketable tomatoes over a long period of time. Researchers have the ability to identify those traits by utilizing gene markers during the breeding process.
Sjoberg briefly discussed a couple of other breeding techniques being utilized that also can speed up the process. One is the use of a technique called double haploid or dihaploid. It is a tissue culture technique that allows breeders to develop uniform lines from a population of plants in one generation. Copies can be made without going back to the traditional method of combining parent 1 and parent 2. The WSU researcher said it is another way to shave time off of the original breeding timeline.
Of course, speeding the breeding process is great for seed companies and growers who are always looking for varieties with improved traits, be it disease resistance, increased shelf life, more flavor, easier to harvest, more uniform and a host of other positive characteristics. But the Australian breeders pulled no punches in discussing their motivation for speed breeding. In a video report found online, researcher Lee Hickey of the University of Queensland said: “Nine billion people…nine billion mouths to feed by 2050, and our crops that we are growing today aren’t good enough to get the job done. So we need breakthroughs in genetics. We need to build these crops to be more productive under warmer climates, (and) more variable droughts. Not to mention rapidly evolving pests and pathogens.”
The research has been going on for eight years with several articles published in scholarly journals explaining the effort more thoroughly, available on the internet.