Featured Research

from universities, journals, and other organizations

Genes Passed From Crops To Weeds Persist For Generations

Date:
August 13, 2001
Source:
Ohio State University
Summary:
Genetic traits passed from crops to their weedy relatives can persist for at least six generations, and probably much longer, according to an Ohio State University study conducted with radishes. This means genetic traits that are developed in crops - such as resistance to insect pests - can become a permanent part of the weed population, in turn posing possible risks to crops.

MADISON, Wisc. - Genetic traits passed from crops to their weedy relatives can persist for at least six generations, and probably much longer, according to an Ohio State University study conducted with radishes.

Related Articles


This means genetic traits that are developed in crops - such as resistance to insect pests - can become a permanent part of the weed population, in turn posing possible risks to crops.

These results suggest that biotech companies should steer clear of developing transgenic radish varieties with beneficial traits that could be passed on to weeds, said Allison Snow, a study co-author and a professor of ecology at Ohio State University.

Transgenic crops are crops engineered with specialized traits such as resistance to viral diseases, insect pests and herbicides.

While the new hybrid weeds may not be as fit at first as their wild parents, they seem to regain reproductive fitness quickly, Snow said.

"It's inevitable that these and other fitness-related traits will make their way into weed populations," Snow said. "The result may be very hardy, hard-to-kill weeds."

In California, the crop itself has become a highly successful and very damaging weed. Scientists suspect that this transition was aided by genes from the wild radish. In fact, wild radish is considered one of the 100 most economically damaging weeds worldwide.

"Gene movement from crops to their wild relatives is an ongoing process that can spur rapid evolutionary adaptation in weeds that will be ultimately harmful to crops," Snow said.

Snow presented the findings August 9 in Madison, Wisc. at the annual Ecological Society of America meeting.

The researchers studied four populations of hybrid and wild radish for six years in Michigan. At the outset, each field consisted of 100 first-generation crop-wild radish hybrids and 100 wild radishes. To monitor the continuation of crop radish genes in the populations, the researchers looked for four genetic traits: two enzymes, flower color and pollen fertility.

On average, the wild radishes reached peak flowering one month before the hybrid plants. The hybrids also produced fewer seeds per fruit than wild plants and fewer viable pollen grains. A large portion of hybrids never produced fruits (60 to 78 percent), while 92 to 97 percent of the wild plants did.

Even so, traits from the original crop - such as white flower color - persisted in subsequent generations of hybrid radishes.

"Even though the effects of delayed flowering and reduced fertility inhibited the movement of certain crop traits to later generations, we did find evidence of crop genes in every generation," Snow said.

In order to compare the lifetime fertility of wild and hybrid varieties, the researchers also grew one population of potted radishes.

Viable pollen averaged 63 percent in the potted hybrids, as compared to 92 percent in wild plants. The hybrids produced only half as many seeds per fruit as wild plants. Although the potted hybrid plants flowered on average half a month later than the potted wild ones, the hybrid radishes still produced enough viable pollen with enough time left in the growing season for pollination to occur.

"The hybrids were capable of ecologically significant levels of reproduction," Snow said. "The second hybrid generation was still at a fitness disadvantage, but to a lesser extent than the first hybrid generation. This indicated that their reproductive fitness was increasing."

The next step is to figure out if crop genes benefit weed populations and also to gauge how easily crops can become wild.

"The constant gene flow between crops and weeds is a subtle process that no one may notice, but evolution can happen very quickly," Snow said.

Snow conducted her research with Kristen Uthus, a graduate student in Ohio State's Evolution, Ecology, and Organismal Biology graduate program and Theresa Culley, a researcher at the University of California, Irvine.

Snow's research was supported by a grant from the National Science Foundation, Ohio State University and the University of Michigan Biological Station.


Story Source:

The above story is based on materials provided by Ohio State University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio State University. "Genes Passed From Crops To Weeds Persist For Generations." ScienceDaily. ScienceDaily, 13 August 2001. <www.sciencedaily.com/releases/2001/08/010810065737.htm>.
Ohio State University. (2001, August 13). Genes Passed From Crops To Weeds Persist For Generations. ScienceDaily. Retrieved December 17, 2014 from www.sciencedaily.com/releases/2001/08/010810065737.htm
Ohio State University. "Genes Passed From Crops To Weeds Persist For Generations." ScienceDaily. www.sciencedaily.com/releases/2001/08/010810065737.htm (accessed December 17, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Wednesday, December 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

When You Lose Weight, This Is Where The Fat Goes

When You Lose Weight, This Is Where The Fat Goes

Newsy (Dec. 17, 2014) Can fat disappear into thin air? New research finds that during weight loss, over 80 percent of a person's fat molecules escape through the lungs. Video provided by Newsy
Powered by NewsLook.com
The Hottest Food Trends for 2015

The Hottest Food Trends for 2015

Buzz60 (Dec. 17, 2014) Urbanspoon predicts whicg food trends will dominate the culinary scene in 2015. Mara Montalbano (@maramontalbano) has the story. Video provided by Buzz60
Powered by NewsLook.com
Rover Finds More Clues About Possible Life On Mars

Rover Finds More Clues About Possible Life On Mars

Newsy (Dec. 17, 2014) NASA's Curiosity rover detected methane on Mars and organic compounds on the surface, but it doesn't quite prove there was life ... yet. Video provided by Newsy
Powered by NewsLook.com
Ivory Trade Boom Swamps Law Efforts

Ivory Trade Boom Swamps Law Efforts

Reuters - Business Video Online (Dec. 17, 2014) Demand for ivory has claimed the lives of tens of thousands of African elephants and now a conservation report says the illegal trade is overwhelming efforts to enforce the law. Amy Pollock reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins