"Perfect Flowers" in the Grapes

"Perfect Flowers" in the Grapes

"Perfect flowers" from grapes "Perfect flowers" from grapes

Today’s breeders try to breed new varieties and produce grapes with better exportability and stronger disease resistance.
It often takes 2 to 4 years to know whether they have the genetic components of "perfect flowers"
.

In the history of grape domestication, the evolution of hermaphrodite flowers is a key feature
.

Most cultivated grapes are now hermaphrodite, while all members of the wild Vitis have only male or female flowers

The female flower sets fruit but produces sterile pollen; the male flower has pollen but no fruit
.

The "perfect flower" carries both sex genes and can self-pollinate

Now, scientists from Cornell University and the University of California, Davis, have collaborated to identify DNA markers that determine the sex of grape flowers
.

In this process, the research team also determined the genetic origin of the "perfect flower"

"This is the first genomic evidence showing that grape flower sex has multiple independent origins,
" said Jason Londo, a geneticist at the Agricultural Research Service of the United States Department of Agriculture and the corresponding author of the study
.

He said: "This research is very important for breeding and production, because we have designed genetic markers that can tell the exact sex characteristics of each vine
.

This way, breeders can only choose the combinations they want in the future

As breeders try to incorporate disease resistance genes from wild species into new breeding lines, the ability to screen the sex of seedlings has become increasingly important
.

Since the sex of grapes cannot be determined solely from the seeds, breeders spent a lot of time and resources to grow grapes, but only a few years later did they know that they were single-sexed, so they had to abandon them

In this study, the research team examined the DNA sequences of hundreds of wild and cultivated grape genomes to determine the unique sex determining regions of male, female, and hermaphrodite varieties
.

They traced the existing male and female DNA back to two separate recombination events that occurred sometime between 6 million and 8000 years ago

Londo’s theory is that ancient grape growers stumbled upon some high-yielding grape vines and collected seeds or cuttings for their own needs—"freezing" the hermaphrodite flower characteristics of cultivated grapes used today
.

The existence of wine grapes and table grapes benefits from a very rare gene exchange
.

In the past 6 million years, this exchange has only occurred twice in nature

Chardonnay and Riesling are unique in that they carry genes from the gene pool of the two events
.

According to Londo, this shows that ancient viticulturalists crossed these two gene pools and bred some of the most important varieties today

Recording the genetic markers that identify male, female, and "perfect flowers" will ultimately help accelerate variety development and reduce breeding costs
.

"The more grape DNA markers are identified, the more breeders will use them to promote the development of the wine and grape industry
.
" said Bruce Reisch, co-author of the paper and professor of horticulture and plant breeding genetics at Cornell University.
Sequencing technology and multi-institutional research cooperation are the key to enabling growers and consumers to obtain better grapes
.
” (Source: Wang Fang, China Science News)

Related paper information: https://doi.
org/10.
1073/pnas.
2023548118

https://doi.
org/10.
1073/pnas.
2023548118