A team of researchers from Virginia Tech and Pennsylvania State University recently discovered some species of parasitic plants, such as the dodder, manage to steal genetic material as well when they establish a direct connection with their hosts.

1. Parasitic Plants Steal Genes
from Hosts to Weaken
Their Defenses
U.S. Lawns

2. Parasitic plants cannot produce energy on their own through photosynthesis. Thus, they
latch onto other plant species using a structure called haustorium to siphon nutrients and
water from the host, affecting entire lawns.
A team of researchers from Virginia Tech and Pennsylvania State University recently
discovered some species of parasitic plants, such as the dodder, manage to steal genetic
material as well when they establish a direct connection with their hosts.
Horizontal Gene Transfer in Parasitic Plants
Horizonal gene transfer (HGT) is a common occurrence in plants. However, the receiving
plant typically does not use the transferred genetic materials. The researchers used
genome-scale datasets to determine whether the parasitic dodder uses the large amounts
of genetic material it taps.
They identified 108 genes stolen from the host plant that are now functional in the parasite.
The dodder has managed to incorporate the stolen genetic material into its own genome
and these now contribute to its haustoria structure, amino acid metabolism, and defense
responses. The dodder also steals one type of gene that produces micro RNAs, which it
sends back to the host as a weapon to weaken its defenses.

3. For the material to become functional in the parasite, the genes have to be full length,
contain the vital parts of a gene, transcribed into an RNA sequence that can build proteins,
and expressed in relevant structures.
Horizontal Gene Transfer as Part of Natural Selection
The researchers suspect that parasitic plants cannot control the type of gene they siphon
because not all of the transferred material are functional. However, natural selection
filters the useless genes over time while retaining the useful ones.
As evidence, the research team found 18 genes in the dodder plant that have been
present in the common ancestor of all dodder species. These genes that have been passed
down through generations may have contributed to the dodder species’ successful spread.
The researchers say that this discovery can propel more studies about HGT. Some of the
explorable topics are whether HGT is a two-way process, if it occurs in other species of
parasitic plants, and if it is possible in non-parasitic plants.

4. Sources:
https://www.sciencedaily.com/releases/2019/07/190722182130.htm
https://uslawns.com/locations/ms/jackson/
https://www.earth.com/news/parasitic-plants-steal-genetic-material/
https://www.nature.com/articles/s41477-019-0458-0