NZ scientists in 'game-changing' plant cloning discovery

Kiwi scientists have helped discover a new gene described as a potential game-changer for cloning in global agriculture. Photo / 123RF

Kiwi scientists have helped discover a new gene described as a potential game-changer for cloning in global agriculture.

The gene allows natural reproduction by cloning in plants, enabling highly desirable traits to be carried through to the next generation rather than lost when the plants reproduce through pollination.

Named PAR, the new gene has been found to control parthenogenesis, a process whereby plant egg cells spontaneously grow into embryos without fertilisation.

Normally, the PAR gene is triggered by fertilisation, but in plants that reproduce by apomixis – which does not require fertilisation - the PAR gene switches on spontaneously, so the egg cells are triggered to start dividing into a new embryo.

Scientists in New Zealand have been working with scientists in the Netherlands – at research company KeyGene and Wageningen University & Research (WUR) – and Japan, at breeding company Takii, to identify ways to produce plant seeds that are genetically identical to the parent plant.

"Being able to reproduce annual crops by apomixis would be a game-changer for farmers worldwide," said Plant of Food Research scientist Dr Ross Bicknell, who has been involved in the research.

"For subsistence farmers in particular this would be revolutionary. Instead of always having to buy seed they would now be able to save their own and use it to grow plants with the same elite characteristics year on year without losing quality.

"That's why this has the potential to be a truly empowering technology, giving autonomy to people who have the least."

Creating seed for an annual plant, such as wheat or rice, required pollination, and as each seed combined genetic characteristics from two parent plants, no two seedlings were the same.

"Or to put it another way, only a very small number of plants in a field of wheat are the very, very best," Bicknell said.

"Now imagine being able to produce a whole crop made up of just those elite individuals. Cloning is not an unusual idea, we already use it for things like fruit trees, grapes and strawberries, but this will bring the advantages of cloning to the crops that support humanity – and that really would be a game-changer for agriculture."

Plants that naturally reproduce by apomixis were found to have a transposon - a small piece of DNA that can jump around the plant DNA - in the promoter of the PAR gene.

The promoter regulates that gene's activity.

"It is very interesting to see a transposon involved in such a key process in two independent species," Lincoln University's Associate Professor Chris Winefield said.

"Transposons are often proposed to be involved in evolution of plants and animals so to see a transposon driving a key process such as apomixis is very exciting."

Researchers at KeyGene have already started researching whether the PAR gene can cause parthenogenesis in plants that do not normally reproduce by apomixis, such as lettuce and sunflower, to further understand how the gene could be used in crop plant breeding.

The new findings have been published in the prestigious journal Nature Genetics.