Subtropical Fruit Crops Research & Education
University of California
Subtropical Fruit Crops Research & Education

Posts Tagged: citrus varieties

Citrus Day Coming Up at UC Riverside


Photo shows Mikeal Roose.

Mikeal Roose, a professor of genetics at UC Riverside.Photo credit: L. Duka.

RIVERSIDE, Calif. ( — The University of California, Riverside will host the 5th annual citrus field day for citrus growers and citrus industry professionals on Jan. 27 at the university's agricultural operations fields.

The event, which will includes a mix of presentations and field tours, is scheduled from 8 a.m. to 3 p.m. Advance registration, which is $25, is required. The deadline is Jan. 22. There will be no day-of-event registration available.

To register visit: For more information call 951-827-5906.

The following is a tentative schedule for the event:

  • 8 a.m. – Introductions by Peggy Mauk, director of agricultural operations at UC Riverside and a subtropical horticulture extension specialist, and Tracy Kahn, curators of UC Riverside's Citrus Variety Collection.
  • 8:10 a.m. – Welcomes from Kathryn Uhrich, dean of UC Riverside's College of Natural and Agricultural Sciences and Michael Anderson, a divisional dean for agriculture and natural resources.
  • 8:30 a.m. – Minimizing the potential for nurseries to contribute to Asian citrus psyllid spread in California – Matt Daugherty, a cooperative extension specialist, entomology. To minimize the potential for nurseries to contribute to Asian citrus psyllid and huanglongbing spread, as occurred in Florida, regulations are in place in California that restrict movement of containerized citrus and require specific insecticide treatments. Daughterty's is evaluating how well such steps reduce the risk of human-mediated Asian citrus psyllid spread. He is using a combination of monitoring in nurseries, field experiments on chemical control efficacy, and characterization of the effects of nursery practices on psyllid management.
  • 9:15 a.m. – Microbiota-based approach to citrus tree health – Philippe Rolshausen, cooperative extension specialist, subtropical horticulture. He will talk about how bacteria, fungi and viruses associated with the plant, either on its surface or inside, can affect plant health and productivity. He will demonstrate how these organisms can be used for disease control. He will use Pierce's Disease found in grapevines as an example and also draw a comparison with Huanglongbing found in citrus.
  • 9:45 a.m. – Low seeded citrus – variation in seed content and its causes – Mikeal Roose, professor, botany and plant sciences. Roose specializes in plant breeding, particularly with citrus.
  • 10:30 a.m. – Break
  • 11 a.m. – Novel detection methods for Huanglongbing – Wenbo Ma, associate professor, plant pathology. Her research is focused on developing methods that detect Huanglongbing by monitoring so-called “effectors” secreted from the bacterial pathogens causing the disease.
  • 12 p.m. – Lunch (catered by Anchos Southwest Grill)
  • 1 p.m. – Pesticide safety training – Vince Samons, UC Riverside agricultural operations.
  • 1:45 p.m. – Walk-thru of the Citrus Variety Collection, Rootstock Trial and Phytophthora root rot trial.

To make a tax-deductible contribution to the Citrus Variety Collection Endowment fund or the Citrus Research Center & Agricultural Experiment Station support fund go to the following link and select College of Natural and Agricultural Sciences then select the specific fund:

citrus cornucopia
citrus cornucopia

Posted on Tuesday, January 10, 2017 at 4:55 PM
  • Author: Sean Nealon
Tags: citrus varieties (2), grapefruit (27), kumquat (2), lemon (100), mandarin (68), orange (69), tasting (2)

'Valentine' - a new pummelo hybrid

In the last two decades, many distinctive citrus selections have become available at retail markets in the US.  These include cultivars such as 'Cara Cara' navel orange, 'Cocktail' pummelo-mandarin hybrid, 'Variegated Pink' lemon, 'Seedless Kishu' mandarin and 'Buddha's Hand' citron.  Among specialty ctirus growers, there is intense interesst in acquiring  nev varieties with novel or unusual chracteristics of appearance, coloration, flavor, size and functional properties.

The newly released pummelo hybrid 'Valentine', combines the large size and low acidity from its pummelo parent, complex, floral taste from 'Dancy' mandarin and juicy red pulp from 'Ruby hybrid.  It matures in mid-February near the Valentine's holiday and when it is cut lengthwise and turned upside down, the flesh of the fruit resembles a vibrant red heart.  It is unique in being a grapefruit-like fruit with anthocyanin pigmentation, which is a potential marketing advantage at a time when many anitoxidant-rich fruits, such as pomegranate, bleuberry and blackberry, have seen sales increase because of their percieved health benefits.

Learn more about this new fruit and other citrus in the UC Variety Collection at:

Valentine pummelo
Valentine pummelo

Posted on Friday, May 24, 2013 at 7:27 AM
  • Author: Toni Siebert, Ottillia Bier, David Karp, Georgios Vidalakis and Tracy Kahn
Webmaster Email: