An international study has raised the possibility of self-fertile kiwifruit cultivars, a move which could save the sector land and labour costs.
The paper "Two Y chromosome-encoded genes determine sex in kiwifruit" is has been published in the top plant journal Nature Plants.
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The paper outlines how Plant & Food Research scientists and their research partners in Japan and the US have discovered a sex determining gene in kiwifruit that could potentially lead to the breeding of hermaphrodite varieties.
Self-fertile kiwifruit cultivars could remove the current need for pollen supplementation, meaning less land and labour would be required for kiwifruit production.
The study has also validated the "two-mutation model" in sex acquisition of plants proposed forty years ago.
The gene called Friendly Boy (FrBy) is necessary for pollen production and is found naturally in Y chromosomes of male kiwifruit plants.
It is the second sex-determinant discovered in kiwifruit after Shy Girl(SyGI), which suppresses fruit production in male kiwifruit plants.
Plant & Food Research scientist Dr Sarah Pilkington said researchers overexpressed the FrBy gene identified by Japanese research partners in rapid-flowering kiwifruit plants.
"We found that expression of FrBy in female kiwifruit resulted in hermaphrodite plants, which means the female plants could both produce and receive pollen, making them capable of self-fertilisation," she said.
The study supports the "two-mutation model" of sex evolution in plants proposed by Deborah and Brian Charlesworth in 1978.
It suggests that at least two gene mutations, one affecting ovule (female) production and one affecting pollen (male) production, are necessary to transform a hermaphrodite species into one with separate sexes.
"The results of this study pave the way for the potential development of hermaphrodite kiwifruit," said Dr Pilkington.
Read the full study here.