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Researchers from Spain and U.S. discover 'seedless' cherimoya gene

Thanks to researchers in the United States and Spain, it may not be long before you find yourself packing a cherimoya, rather than an apple or banana, in your kids’ lunchboxes.

The researchers recently combined their expertise in an effort to show how to develop a seedless version of the Cherimoya – which Mark Twain called "the most delicious fruit known to man."

The cherimoya, also known as the custard apple, and the closely related sugar apple and soursop, all are known for having big, awkward seeds.  New seedless versions of these tasty fruits would undoubtedly be much more appealing to consumers.

"This could be the next banana — it would make it a lot more popular," said Charles Gasser, a professor of molecular and cellular biology at UC Davis.

He noted that, although all commercial banana varieties are seedless, bananas in their natural state have up to a hundred seeds.

The cherimoya project began in Spain, where researchers José Hormaza, Maria Herrero and graduate student Jorge Lora at the Consejo Superior de Investigaciones Cientificas labs in Malaga and Zaragoza, Spain, were studying the seedless variety of sugar apple. When they looked closely at the fruit, they noticed that the ovules, which would normally form seeds, lacked an outer coat.

They looked similar to the ovules of a mutant of the lab plant Arabidopsis that was discovered by Gasser's lab at UC Davis in the late 1990s. In Arabidopsis, the defective plants do not make seeds or fruit. But the mutant sugar apple produces full-sized fruit with white, soft flesh without the large, hard seeds.

The Spanish team contacted Gasser, and Lora came to UC Davis from Malaga to work on the project in Gasser's lab. He discovered that the same gene was responsible for uncoated ovules in both the Arabidopsis and sugar apple mutants.

"This is the first characterization of a gene for seedlessness in any crop plant," Gasser said.

Although there are seedless varieties of other commercial fruit crops in the grocery story, those are usually achieved by selective breeding. And – since the plants have no seeds – they are reproduced using plant cuttings or other methods of vegetative propagation.

Gasser is hopeful that discovery of this new gene could open the way to produce seedless varieties in sugar apple, cherimoya and perhaps other fruit crops.

In addition to its implication for commercial crops, the team’s research also sheds light on the evolution of flowering plants, Gasser said. Cherimoya and sugar apple belong to the magnolid family of plants, which branched off from the other flowering plants quite early in their evolution.

"It's a link all the way back to the beginning of the angiosperms," Gasser said, referring to the large group of plants and trees characterized by having flowers and seeds.

The researchers published a paper on describing their work in the March 14 issue of the scientific journal Proceedings of the National Academy of Sciences. Their research was funded by grants from the Spanish government, the European Union and the U.S. National Science Foundation.


Posted on Thursday, March 17, 2011 at 8:41 AM

Master Food Preserver Program returns to Los Angeles County

UC Cooperative Extension is pleased to announce the return of the Master Food Preserver (MFP) Program to Los Angeles County. After 10 years of being inactive, LA County residents have spurred on the revival of the Master Food Preserver Program through a renewed interest in home food preservation.

The classes, which are slated to begin on March 28, will be taught primarily by UC Master Food Preserver Ernest Miller. Miller, a formally trained chef, has years of experience with home food preservation and writes about food preservation in his blog PreserveNation.

Miller is currently the chef at The Farmer's Kitchen, a project of Sustainable Economic Enterprises of Los Angeles.  He earned his Master Food Preserver certificate by faithfully attending 13 weeks of classes in San Bernardino County. San Bernardino was the last remaining MFP program in Southern California, that is, until Orange County recently began an MFP program in February of this year.

“As the sole Master Food Preserver in Los Angeles for over a year, I know that there is a tremendous interest in traditional methods of food preservation,” said Miller. “The recent resurgence of gardening has definitely increased interest in food preservation. After all, there are only so many tomatoes you can eat fresh."

The program will run for 12 weeks, meeting in the LA County Cooperative Extension community demonstration kitchen. Eighteen enthusiastic LA County residents who were accepted into the program will learn everything preservation – from canning, fermenting, pickling and curing to smoking, dehydrating and brewing. MFPs will also learn about coping with emergencies and disasters. According to Miller, “Master Food Preservers do teach people how to can and dry food, but one of the lesser-known aspects of the MFP program is teaching people proper long-term and emergency food preparedness. Clearly, the immense tragedy currently taking place in Japan demonstrates the need for people to learn how to prepare for natural disasters, especially in earthquake-prone California.”

Once trained, LA County Master Food Preservers will begin conducting food preservation classes and workshops for the general public. The response to this program has been tremendous among LA County residents. Many food preservation enthusiasts are already looking forward to MFP-led workshops and demonstrations, and are hoping to one day become certified MFPs when future classes are held.

Support for the University of California Cooperative Extension Los Angeles County Master Food Preserver Program has been provided by the Metabolic Studio, a direct charitable activity of the Annenberg Foundation.

For more information about the MFP program in Los Angeles County, please contact LA County Nutrition, Family & Consumer Sciences Advisor Brenda Roche at, (323) 260-3299.

Posted on Tuesday, March 15, 2011 at 7:28 AM
  • Author: Brenda Roche

Eating right doesn’t have to break the budget

Even though dietitians have for decades strongly recommended eating lots of fruit and vegetables daily, very few Americans hit the mark. Food prices, taste, inconvenience, and a failure to understand the link between diet and health have been blamed for Americans’ poor food choices.

New research by the USDA Economic Research Service dispels one of those obstacles. The study determined that buying the recommended amount of fruits and vegetables costs on average only $2 to $2.50 per day.

“For those with access and the means to buy them, the assertion that fruits and vegetables are too expensive is not a good excuse,” said UC Cooperative Extension nutrition, family and consumer sciences advisor Cathi Lamp. “Consumers should be able to purchase a days’ worth of fruit and vegetables for less than it costs to buy a cheeseburger.”

The ERA researchers estimated the average retail prices of 153 fresh and processed fruits and vegetables. Processed fruits and vegetables included frozen, canned and dried plus 100 percent fruit juice.  They also estimated the average price per edible cup for each vegetable and fruit.

Costs in the study were defined as the average prices paid by all American households for a food over a one-year period, including purchases in different package sizes, under different brand names and at different types of retail outlets (including supercenters such as Wal-Mart, wholesale club stores like Costco, traditional grocery stores such as Safeway, Kroger and Albertsons, and convenience stores.)

The research indicated that:

  • Fruits and vegetables cost about 50 cents per edible cup.
  • The lowest average price for any of the 59 fruits in the study was for fresh watermelon, at 17 cents per cup. The highest average price was for fresh raspberries, at $2.06 per cup.
  • Among the 95 fresh and processed vegetables in the study, a cup of dry pinto beans was the least expensive at 13 cents. The most expensive was frozen asparagus cuts and tips at $2.07 per cup.
  • Processed fruits and vegetables were not consistently more or less expensive than fresh produce, but with certain types of produce, the prices varied quite a bit. Canned carrots, at 34 cents per cup, were more expensive than fresh carrots, at 25 cents per cup. However, canned peaches, at 58 cents per cup, were less expensive than fresh, at 66 cents per cup.

Lamp suggested smart shopping can also help consumers reduce the cost of their fruits and vegetables. For example, buy fresh fruit and vegetables in season, use canned and frozen fruit and vegetables when it is cheaper and stock up when items are on sale or when shopping at a supercenter or wholesale club.

Posted on Thursday, March 10, 2011 at 7:07 AM

Swaying both ways

Imagine if rice – yes, that semiaquatic species that is typically cultivated under partially flooded conditions – could be both flood- and drought-tolerant. Such a rice variety would benefit rice growers and consumers worldwide and would be less vulnerable to weather extremes that may result from global climate change.

Now UC Riverside experiments demonstrate that such rice is already here. Genetics professor Julia Bailey-Serres’ research group reports in a recent issue of The Plant Cell that flood-tolerant rice is also better able to recover from drought.

“Flood tolerance does not reduce drought tolerance in these rice plants, and appears to even benefit them when they encounter drought,” Bailey-Serres says.

She and her team – Takeshi Fukao, a senior researcher, and Elaine Yeung, an undergraduate student – focused on Sub1A, a gene responsible for flood or “submergence” tolerance in rice. Sub1A works by making the plant dormant during submergence, allowing it to conserve energy until the floodwaters recede. Indeed, rice with the Sub1A gene can survive more than two weeks of complete submergence.

Plant breeders have already profited farmers worldwide – especially in South Asia – by having transferred Sub1A into high-yielding rice varieties without compromising these varieties’ desirable traits — such as high yield, good grain quality, and pest and disease resistance.

Bailey-Serres’s lab found that in addition to providing robust submergence tolerance, Sub1A aids survival of drought. The researchers report that at the molecular level Sub1A serves as a convergence point between submergence and drought response pathways, allowing rice plants to survive and re-grow after both weather extremes.

“Sub1A properly coordinates physiological and molecular responses to cellular water deficit when this deficit occurs independently, as in a time of drought, or following ‘desubmergence,’ which takes place when flood waters recede,” says Bailey-Serres who was the lead recipient of the 2008 USDA National Research Initiative Discovery Award.

Next, her colleagues at the International Rice Research Institute in the Philippines will test the Sub1A rice for drought tolerance in the field. What are some other implications of this research? One that comes to mind is that the “Got Rice?” slogan might have to drop the question mark, and put in its place a solid period!

Posted on Tuesday, March 8, 2011 at 8:45 AM

National Nutrition Month®

March is National Nutrition Month®! Thirty-eight years ago a week long campaign to promote nutrition was launched by the American Dietetic Association. That same campaign gained public popularity and has since expanded to what is now known as National Nutrition Month®. This March the theme is “Eat Right with Color.” The American Dietetic Association (ADA) recommends:

Start with the basics. Use MyPyramid to build a healthy, balanced diet. Visit for your personalized food plan.

Nutrient-dense foods. The ADA also suggests focusing foods that are rich in vitamins and minerals and lower in calories and fat.  For example, whole grain toast with low-fat cheese, fruit, and a cup of coffee with low-fat milk will provide more nutrients than a muffin and a coffee drink filled with sugared syrup and whipped cream.  Try the yummy National Nutrition Month recipes, which will satisfy your taste buds and your body’s craving for nutrients!

Variety is important
. Varying the foods you consume will ensure you are getting all the nutrients that your body needs. Aim to build a rainbow on
your plate!

Make the most of family meal-time. The eating habits children learn today are the habits they will have tomorrow. Model healthy eating habits with children to help them make healthy choices.

Physical activity is important for “managing weight and overall health.” MyPyramid encourages at least 30 minutes per day.

These five key messages are at the core of all the events taking place during National Nutrition Month®. Activities in different venues are put on by the ADA to spread nutrition awareness. In schools and at community centers there are activities and/or events taking place to celebrate National Nutrition Month®. For more information about events or activities or information in about National Nutrition Month®, click here.

Blog contributors: Connie Schneider, Ph.D., R.D., Kathleen Burke, CSUF Dietetic Intern, & Shelby MacNab, Nutrition Program Manager

National Nutrition Month 2011 Recipes
National Nutrition Month 2011 Recipes

Posted on Thursday, March 3, 2011 at 9:49 AM
  • Author: Shelby MacNab

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