Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sweet Citrus Varieties with Deep Orange Rind Released by UC Riverside

21.06.2002


Three new varieties of tangerines - the TDE2, TDE3, and TDE4 - are the University of California’s most recent citrus varieties to be released for commercial production. The tangerines, which are complex hybrids, are siblings since they share the same parents. The varieties will be patented and eventually be given trademarked names. The three tangerines are large fruited compared to other varieties, have a sweet taste, and bear fruit with a deep orange rind.

"While the new tangerines share many similarities, they also differ from each other in their characteristics," said Mikeal Roose, professor of genetics at UC Riverside. "They do have one outstanding attribute however: all three are very low seeded, less than one seed per fruit, even when the trees are planted with other varieties. This is a highly-sought attribute for the fresh fruit market."

Although the crosses were made in 1973, it was not until the 1980s that now-retired UC Riverside Professors Robert K. Soost and James W. Cameron recognized the potential of these individual seedlings for commercial development.



Each seedling produced from a cross between two citrus varieties has a unique genetic makeup. "You can think of citrus genetics as similar to human genetics," said Roose, who was assisted in developing the new tangerines by UC Riverside staff scientist Tim Williams. "When you cross a mother and a father, the children may have some similarities but they are different from one another."

The TDE2, TDE3, and TDE4 are now being released for commercialization in California under non-exclusive licensing agreements with the University of California. Licensed growers and wholesale nurseries in California can obtain budwood, propagate the varieties and freely market the resulting trees and fruit. The University of California does not produce trees for sale to the public. It will take a year or two before trees become available for planting, and another two or three years before the young trees produce much fruit.

"The tangerines also hold very well on the trees," said Roose. "In Riverside, the TDE2 is good-tasting when picked from the tree anytime between February and May; the TDE3 is good-tasting when picked from the tree anytime between January and March; for the TDE4, the range is February to April."

There are, however, some unknowns associated with the new tangerines. For example, it is not clear how well the trees will yield when isolated from other citrus plants. "Some citrus require pollination or need stimuli like plant hormone sprays to set good crops," said Roose. "We hope to find out in the next two years how our new varieties perform." Like many tangerines, the new varieties also have ’alternate bearing’ - a big crop one year followed by a much lower yield the next year(s). When the crops are very light, fruit size tends to get large and the rind gets rough and bumpy, Roose noted.

"The three new varieties are also quite thorny," said Roose. "This is a common characteristic of new hybrids. Moreover, the tree size for all three varieties is large for tangerines. All three new varieties grow more like orange trees, we’ve found." Characteristics of fruit of the three new varieties are listed in Table 1.

  TDE2 TDE3 TDE4
Average fruit size
for a tangerine
large medium-large large
Mean width 2.95 in (75 mm) 2.60 in (66 mm) 2.95 in (75 mm)
Mean height 2.32 in (59 mm) 2.20 in (56 mm) 2.30 in (58 mm)
Mean weight 6.5 oz (185 g) 4.75 oz (135 g) 6.0 oz (175 g)
Avg. juice content (%) 49 48 42


Table 1. Characteristics of the TDE2, the TDE3, and the TDE4. All three tangerines have an attractive deep orange rind color, have a rich fruit flavor and are marked by the virtual absence of seeds even in mixed plantings.

"We are very excited about the new tangerines," said Roose. "Besides having considerable potential as commercial varieties, all three should be of great interest to backyard citrus growers looking to add interesting new tangerines to their collections."

UC Riverside scientists have a long tradition in citrus research. In 1907, the University of California established the Citrus Experiment Station in Riverside to support Southern California’s growing citrus industry with scientific data to improve production. In 1917, the station moved to its present site, which would also become a new University of California campus in 1954.

Now known as the Citrus Research Center-Agricultural Experiment Station, the work of the center has grown to include all aspects of agricultural production in arid and semi-arid subtropical lands. Research on citrus production and development of new varieties remains a major focus of UC Riverside agricultural research.

UC Riverside is also home to the University of California Citrus Variety Collection of some 900 varieties that have been used extensively to solve citrus disease problems and improve commercial varieties.


The University of California, Riverside, established in 1954, offers undergraduate and graduate education to nearly 15,000 students. It is a member of the 10-campus UC system, which is the largest public research university system in the world. The picturesque 1,200-acre UC Riverside campus is located at the foot of the Box Springs Mountains near downtown Riverside, California.

Contact: melissa.freed@ucop.edu
Contact: anne@citrusresearch.org

News Media Contact: Iqbal Pittalwala
909-787-2645
e-mail: iqbal@citrus.ucr.edu

Iqbal Pittalwala | EurekAlert!
Further information:
http://www.ucr.edu

More articles from Agricultural and Forestry Science:

nachricht Kakao in Monokultur verträgt Trockenheit besser als Kakao in Mischsystemen
18.09.2017 | Georg-August-Universität Göttingen

nachricht Ultrasound sensors make forage harvesters more reliable
28.08.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>