Big differences found in male and female jojoba plant sex genes

Date:
October 14, 2021
Source:
University of Queensland
Summary:
Hot desert sex has resulted in major genetic differences between
male and female jojoba plants -- one of only 6 percent of plants
that require a male and female plant to reproduce. New research
suggests male and female jojoba plants have diverged so much, that
the jojoba plant has more novel sex genes than any other known
living organism. The discovery may help researchers develop a DNA
test to identify male and female jojoba plants, which cannot be
distinguished from each other as seedlings - and shed light on
how plants adapt to environmental stress.



FULL STORY ==========================================================================
The hot and dry desert environment has led to big genetic differences
between male and female jojoba plants, a discovery which could boost
jojoba production and shed light on how plants adapt to environmental
stress.


==========================================================================
A team of researchers in a collaboration between King Faisal University
and The University of Queensland have identified a wide divergence of
sex chromosomes in jojoba.

UQ's Queensland Alliance for Agriculture and Food Innovation research
leader Professor Robert Henry said that most plants were hermaphrodites
and contained both male and female parts.

"Just six percent are dioecious, like jojoba, requiring both a male
plant and female plant to reproduce.

"Jojoba plants reproduce through sexual reproduction, the way humans
do, but male and female genomes in humans are 99.9 per cent the same,
whereas in jojoba, there is something like a 15 per cent difference.

"People say men are from Mars and women from Venus when there is a 0.1
genetic difference between the sexes, but male and female jojoba plants
have diverged so much more genetically -- the harsh environments in which
they grow have resulted in the plant having more novel sex genes than
any other known living organism." The discovery may help researchers
develop a DNA test to identify male and female jojoba plants, which
cannot be distinguished from each other as seedlings.



========================================================================== Jojoba oil is derived from liquid wax from the seed of female Simmondsia chinensis plants, a shrub native to the deserts of North America.

The plant is known for its high-temperature and high-salinity tolerance,
and its oil is used in skin care and pharmaceuticals, with applications
for medical and industrial-related products.

Only female plants carry seed.

"As mature plants, the male and female are very different," Professor
Henry said.

"The females are bigger, the males tend to be smaller plants and a
different shape.



==========================================================================
"The females have much deeper root systems." Professor Henry said a
problem for jojoba famers was that although in the wild the male-female
jojoba plant growth ratio was similar, in cultivation systems, five
times more males were produced than females.

"Growers don't want to plant males -- they have to dig out the male
plants and replant," he said.

"It's not a good use of resources in a harsh growing environment."
Professor Henry said male and female jojoba plants may have evolved
in response to differing reproductive resource allocation requirements
under the stress of the desert environment.

"Male specific regions included many flowering-related and stress response genes," he said.

Female plants devote resources to seed production, and greater root
growth allows the female plants to establish for the longer growth phase required to support seed production.

The global jojoba oil market is growing at a rate of 8.4 per cent
per annum.

Key production regions for jojoba in Australia are the central western
plains of New South Wales and southern Queensland.

The United States of America accounted for 39 per cent of jojoba
production in 2019 -- Mexico, Israel, Chile and Argentina are other
major producers.

Jojoba is also being planted in Saudi Arabia at the campus of King Faisal University with plans for large-scale plantings.

========================================================================== Story Source: Materials provided by University_of_Queensland. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. Othman Al‐Dossary, Bader Alsubaie, Ardashir
Kharabian‐Masouleh, Ibrahim Al‐Mssallem, Agnelo Furtado,
Robert J. Henry. The jojoba genome reveals wide divergence of the
sex chromosomes in a dioecious plant. The Plant Journal, 2021;
DOI: 10.1111/ tpj.15509 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/10/211014142007.htm

--- up 6 weeks, 8 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)