Trends in Plant Science
ReviewOpportunities for Products of New Plant Breeding Techniques
Section snippets
New Plant Breeding Techniques Facilitate Breeding of Improved Crop Varieties
Crop improvement is an important endeavor if we are to meet the demands of a growing population (a worldwide population of 9 billion people is projected for 2050), for which food production needs to be increased, while at the same time the environmental impact of food production needs to be reduced. To respond adequately, we should optimally apply all existing tools to breed improved crops and maximize any potential future applications for increasingly sustainable food production.
Plant breeding
NPBTs Produce Three Types of Improved Plant
Products from NPBTs may be grouped into three classes: (i) improved plants that contain a new DNA fragment (usually a new gene); (ii) improved plants that do not contain a new DNA fragment, but have a mutation or modification in their own DNA; and (iii) improved plants that do not contain a new DNA fragment or any modification of their DNA (Figure 1, Key Figure). Below, we describe these different product classes.
NPBT Products that Contain New DNA Fragments
Products made with cisgenesis, intragenesis and specific cases of genome editing using SSN3 technology contain new DNA fragments (Table 1, Improved plant 1). Both cisgenesis and intragenesis are concepts relevant to genetic transformation technology and concern the origin of the inserted DNA. For cisgenesis, a copy of a complete natural gene, including the promoter and terminator sequences, from the sexual compatible gene pool is introduced. This is often an allele with beneficial
NPBT Products that Contain (Small) Modifications of Their Own DNA
This class includes products made with one of the SSN technologies (an explanation of SSN-technology variants is given in Box 2) or with oligo-directed mutagenesis (ODM) (Table 1, Improved plant 2). These technologies aim to induce small modifications to existing genes in the plant genome. This may result in knockout mutations (by SSN-1 through the induction of deletions leading to reading frame-shift mutations or by SSN-2 through editing an amino acid codon into a stop codon), modified gene
NPBT Products that Do Not Contain Altered DNA
Some of this third class of products of NPBT facilitate breeding, such as by introducing recombinant genes that change the expression of one or more endogenous genes with the aim of speeding up breeding processes (reverse breeding or induced early flowering). Others aim at prolonged gene silencing (RNA-directed DNA methylation; RdDM), to replace alleles by more beneficial ones (SSN-3 for gene replacement) or is used to test the effect of novel genes (Agroinfiltration). In the absence of an
Concluding Remarks and Perspectives
The rapid developments in the field of NPBTs continuously add new and valuable tools to the plant breeder's toolbox. This enables the faster and more efficient creation of new crop varieties to meet the demand for sustainably improving agricultural productivity. All NPBTs have a similar aim, namely to enable crop improvements that are difficult (in terms of time and effort) to obtain through traditional breeding methods. The variety of approaches that are known as NPBTs complicates a comparison
Acknowledgement
This work was funded by the Ministry of Economic Affairs of The Netherlands as part of the programme ‘Sustainable plant production systems’ (BO-20-003-006).
Glossary†
- Agroinfiltration
- a technique using Agrobacterium as a tool to achieve temporary and local expression of genes in plant tissue. Agroinfiltration is applied for testing the reaction of target plants to transgenic proteins, or for functional gene analysis in plants.
- Cisgenesis
- the production of plants by genetic modification using only genes from the species itself or from a species that can be crossed with this species using traditional methods (for overview of these traditional methods, see iv).
References (48)
Caution required for handling genome editing technology
Trends Biotechnol.
(2014)- et al.
Towards social acceptance of plant breeding by genome editing
Trends Plant Sci.
(2015) The development of a cisgenic apple plant
J. Biotechnol.
(2011)- et al.
Comparative regulatory approaches for groups of new plant breeding techniques
New Biotechnol.
(2013) Silencing the major apple allergen Mal d 1 by using the RNA interference approach
J. Allergy Clin. Immunol.
(2005)Reducing the incidence of allergy and intolerance to cereals
J. Cereal Sci.
(2014)Consumer attitudes towards hypoallergenic apples that alleviate mild apple allergy
Food Qual. Prefer.
(2011)Are we ready for back-to-nature crop breeding?
Trends Plant Sci.
(2015)Transient expression of virally delivered meganuclease in planta generates inherited genomic deletions
Mol. Plant
(2015)Deployment of new biotechnologies in plant breeding
Nat. Biotechnol.
(2012)