Posts Tagged: Mikeal Roose
Three citrus trees that produce inedible fruit at the UC Lindcove Research and Extension Center in Visalia may be a game-changer for the citrus industry, reported Ezra David Romero on Valley Public Radio.
The trees are thought to be resistant to huanglongbing, a severe disease of citrus that has devastated the Florida industry and could become a serious problem in California. The citrus-saving potential of the three 34-year-old trees was outlined in an article by UC Agriculture and Natural Resources writer Hazel White in the most recent issue of California Agriculture journal.
UC Riverside citrus breeder Mikeal Roose collected seed from the trees and will test seedlings as soon as they are large enough.
"So what (breeders) have to do is cross this with some edible varieties and eventually create something that has the gene for resistance, but also the genes for good fruit," said Beth Grafton-Cardwell, Lindcove director and research entomologist.
Huanglongbing disease has cut citrus production in Florida by more than half. It's been found in residential citrus trees in Southern California, but hasn't reached the state's vast commercial orchards yet. Grafton-Cardwell said she expects the disease will arrive in 4 or 5 years.
The story recounts how plant geneticist Mikeal Roose used irradiation on W. Murcott budwood to induce mutations that improve the fruit.
“Farmers have long selected citrus varieties that are low-seed, that have the same kinds of chromosomal rearrangements stimulated by the same thing—there’s natural radiation around all the time and it can affect the trees at any time.”
The advantage of inducing mutations, Roose explained, rather than waiting for the sun to trigger genetic variation, is that it can be targeted toward manipulating one particular feature—a kind of rapid prototyping for agriculture. The radiation accelerates the output of new genetic compositions. Each is then cultivated, screened and tested with the hope that at least one offspring will be reliably superior to its antecedent.
'Doom the Broom' demo is scheduled Thursday in Paradise
A live fire demonstration will help illustrate the need to clear growth from around structures and to be aware of the growth of Scotch, Spanish and French broom Thursday in the parking lot at 5400 Clark Road, Paradise, Calif. Glenn Nader, UC Cooperative Extension advisor for Sutter-Yuba counties, an expert in livestock and natural resources, will talk about spraying herbicides to control the weeds.
The event will go from 10:30-11:45 a.m., rain or shine. The fire demonstration will be at 11:05 a.m./span>
A new, virtually seed-free mandarin will for the first time be sold in California grocery stores, but consumers may not even notice, according to an AP story by Jeff Nachtigal published late last week. Google News reports that the article made its way into about 200 news outlets.
The story was also written up by reporter Mark Muckenfuss of the Riverside Press-Enterprise in mid-January.
UC Riverside began releasing budwood for Tango mandarins in 2006; more than a million trees are now growing in California. Their first commercial crop is being harvested this month.
Tango is the result of a mutation induced by irradiating budwood of W. Murcott mandarin in UC Riverside genetics professor Mikeal Roose's lab. It has all the good qualities of W. Murcott, but doesn't produce seeds even if bees visit the blossoms covered in pollen from other citrus trees.
Roose told Nachtigal the new mandarin is "like a new car with all the details of the previous year's model, but one that gets 10 miles more to the gallon."
"It's probably the best piece of fruit that's come along for years for citrus growers," Roose was quoted.
Roose said Tango will most likely be marketed as Cuties and Delites. Some may be sold under the Tango name at grocery stores and farmers markets.
W. Murcott mandarin (left) and Tango (right).