Aug. 9, 2019
Representing National Seed Associations and Companies in 75 countries, the International Seed Federation (ISF) is the voice of the global seed sector and stands for a world where the best quality seed is accessible to all, supporting sustainable agriculture and food security. ISF’s mission is to create the best environment for the global movement of seed and to promote plant breeding and innovation.
In view to meet the global challenges like climate change, a growing world population and the need for resource efficient farming systems, plant breeding innovation will definitely need to play a role (Fig. 1). New plant varieties that can better stand pests and diseases with fewer inputs, plants that have stabile yield despite a changing climate and plants with increased productivity, by maximizing resource use efficiency in regard of water, land and nutrients can contribute to meet these goals (Pereira 2016).
The role of plant breeding in meeting global challenges
The plant breeding innovation tradition
Plant breeding has a history of innovation (Fig. 2). Since the discovery of the laws of genetic by Gregory Mendel plant breeders have developed improved breeding methods to make the two major steps in breeding a) increasing genetic diversity, and b) selecting the best performing plants, more targeted and efficient.
Milestones in Plant Breeding
Starting with intentional cross breeding beginning of the 20th century, the first concepts for hybrid breeding were introduced during the 1920’s. One major goal of breeding is to continuously make use of or increase genetic diversity. First attempts to increase genetic diversity by technical means started in the 1930’s with using radiation to induce random mutations in the plant’s genome followed by intense selection procedures to find valuable new traits.
Since the 1960’s new methods for tissue culture improved clonal breeding and wide crosses through embryo rescue technologies as well as speeding up breeding cycles by using microspore cultures by inducing double haploid plants and with that save additional steps in backcross breeding to get homozygous plants were used.
With the new technologies of genome sequencing and the elucidation of gene functions it was possible to introduce SMART breeding methods that improve the selection process by assigning genetic markers to specific traits to more efficiently select for these traits or by using genetic markers to genetically fingerprint plants and select those plants that best combine in cross- or hybrid breeding. Also, the first transgenic plants were developed.
Precision breeding as an integral part of the wholistic breeding approach
New molecular tools of precision breeding help breeders to do their job in an even more precise manner compared to the past. Especially the new tools for genome editing, like ODM (oligonucleotide mutagenesis) or Crispr–Cas provide mechanisms to not only randomly increase genetic variation as it was done by radiation or chemical mutagenesis but also to precisely introduce mutations in genes of known functions to either impair or improve their function. With this, these precision breeding tools can create plants that might also have been produced by conventional breeding methods like chemical or radiation mutagenesis. These plants would in most cases not be distinguishable with respect to the breeding methods that have been used to create these plants (Scientific Advice Mechanism (SAM) 2018). The only difference lies in the efficiency of the process.
All these molecular precision breeding tools can help to improve specific traits, but they need to be integrated into the breeding cycle (Fig. 3). Plant breeding always takes a wholistic approach by looking at all relevant agronomic characteristics. A plant that has an improved pest resistance, but does not perform in yield characteristics or quality, is of no value to the breeder and farmer. This is why -despite the increased efficiency and speed of improving single characteristics by precision breeding methods- it will not release the breeder from testing his candidate varieties in the field over several years and locations to check the overall agricultural performance of a potential new variety.
The Plant Breeding Innovation Cycle
Read more in the original article, The global need for plant breeding innovation
, Jorasch, P. Transgenic Res
(2019) 28(Suppl 2): 81. https://doi.org/10.1007/s11248-019-00138-1