(Press-News.org) This press release is available in Spanish.
U.S. Department of Agriculture (USDA) scientists in Fort Pierce, Fla. are helping citrus growers and juice processors address the threat posed by Huanglongbing (HLB), a disease that is costing the citrus industry millions of dollars each year.
Citrus trees infected with HLB, also called citrus greening, usually die within five to 10 years. Fruit on infected trees often falls to the ground before harvest, and fruit that remains on trees may become misshapen and sometimes only partially ripen.
Supervisory horticulturalist Elizabeth Baldwin with USDA's Agricultural Research Service (ARS) in Fort Pierce is investigating the effects of HLB on the taste of orange juice produced from diseased trees. Her goal is to provide help while a permanent solution is found.
She and her colleagues at the agency's U.S. Horticultural Research Laboratory evaluated fruit with or without HLB symptoms—produced over two growing seasons—for a number of fruit and juice characteristics. They compared Midsweet, Hamlin, and Valencia oranges, the three principal varieties harvested for processing, and used gas and liquid chromatography to analyze juice compounds.
They found that orange juice from the fruit with HLB symptoms was often higher in limonin and nomilin, compounds that can give the juice a bitter taste, but that the compounds were generally below levels that could be detected by human taste panels.
In another study, they investigated how HLB infection affects juice quality in the same three varieties of orange with respect to cultivar, maturity, and processing methods. The results showed tremendous variability, depending on the harvest date and variety of orange. In general, the researchers found more of a problem with off-flavored juice from diseased Hamlin orange trees than with diseased trees of the Valencia and Midsweet varieties.
But the researchers concluded that using some fruit that has HLB symptoms would not cause problems in commercial operations as long as fruit with and without symptoms, harvested from several varieties, locations, and seasons, was mixed together.
ARS is the USDA's principal intramural scientific research agency, and this research supports the USDA goal of promoting international food security.
Read more about the research in the January 2013 issue of Agricultural Research magazine.
USDA is an equal opportunity provider and employer. To file a complaint of discrimination, write: USDA, Office of the Assistant Secretary for Civil Rights, Office of Adjudication, 1400 Independence Ave., SW, Washington, DC 20250-9410 or call 866-632-9992 (Toll-free Customer Service), 800-877-8339 (Local or Federal relay), 866-377-8642 (Relay voice users). END
Fighting back against citrus greening
ELSE PRESS RELEASES FROM THIS DATE:
Diet, parental behavior, and preschool can boost children's IQ
Supplementing children's diets with fish oil, enrolling them in quality preschool, and engaging them in interactive reading all turn out to be effective ways to raise a young child's intelligence, according to a new report published in Perspectives on Psychological Science, a journal of the Association for Psychological Science. Using a technique called meta-analysis, a team led by John Protzko, a doctoral student at the NYU Steinhardt School of Culture, Education, and Human Development, combined the findings from existing studies to evaluate the overall effectiveness ...
Black silicon can take efficiency of solar cells to new levels
This press release is available in German. Scientists at Aalto University, Finland, have demonstrated results that show a huge improvement in the light absorption and the surface passivation on highly absorbing silicon nanostructures. This has been achieved by applying atomic layer coating. The results advance the development of devices that require high sensitivity light response such as high efficiency solar cells. This method provides extremely good surface passivation. Simultaneously, it reduces the reflectance further at all wavelengths. These results are ...
DNA and quantum dots: All that glitters is not gold
A team of researchers at the National Institute of Standards and Technology (NIST) has shown that by bringing gold nanoparticles close to the dots and using a DNA template to control the distances, the intensity of a quantum dot's fluorescence can be predictably increased or decreased.* This breakthrough opens a potential path to using quantum dots as a component in better photodetectors, chemical sensors and nanoscale lasers. Anyone who has tried to tune a radio knows that moving their hands toward or away from the antenna can improve or ruin the reception. Although ...
More than 1 brain behind E=mc2
Two American physicists outline the role played by Austrian physicist Friedrich Hasenöhrl in establishing the proportionality between the energy (E) of a quantity of matter with its mass (m) in a cavity filled with radiation. In a paper about to be published in EPJ H, Stephen Boughn from Haverford College in Pensylvannia and Tony Rothman from Princeton University in New Jersey argue how Hasenöhrl's work, for which he now receives little credit, may have contributed to the famous equation E=mc2. According to science philosopher Thomas Kuhn, the nature of scientific progress ...
National Cancer Centre Singapore scientists discover p53 mutation hinders cancer treatment response
Reducing the level of mutant p53 gene increases susceptibility to treatment Scientists from the National Cancer Centre Singapore (NCCS) have discovered the workings of the gene that has been hindering treatment response in cancer patients. This discovery was made after 5 years of studying the mutant form of the p53 gene, the major tumor suppressor in humans, which is generally found mutated in over 50% of all type of human cancers. The dominant-negative (DN) effect of the mutant p53 gene in cancers was found to affect the outcome of cancer treatment modalities. DN effect ...
Evolution inspires more efficient solar cell design
The sun's energy is virtually limitless, but harnessing its electricity with today's single-crystal silicon solar cells is extremely expensive — 10 times pricier than coal, according to some estimates. Organic solar cells — polymer solar cells that use organic materials to absorb light and convert it into electricity — could be a solution, but current designs suffer because polymers have less-than-optimal electrical properties. Researchers at Northwestern University have now developed a new design for organic solar cells that could lead to more efficient, less expensive ...
Quantum communication: Each photon counts
This press release is available in German. The detector combines near-unity detection efficiency with high timing resolution and has a very low error rate. The results have been published by Nature Communications (doi:10.1038/ncomms2307). Ultrafast, efficient, and reliable single-photon detectors are among the most sought-after components in photonics and quantum communication, which have not yet reached maturity for practical application. Physicist Dr. Wolfram Pernice of the Karlsruhe Institute of Technology (KIT), in cooperation with colleagues at Yale University, ...
NIST's 'nanotubes on a chip' may simplify optical power measurements
The National Institute of Standards and Technology (NIST) has demonstrated a novel chip-scale instrument made of carbon nanotubes that may simplify absolute measurements of laser power, especially the light signals transmitted by optical fibers in telecommunications networks. The prototype device, a miniature version of an instrument called a cryogenic radiometer, is a silicon chip topped with circular mats of carbon nanotubes standing on end.* The mini-radiometer builds on NIST's previous work using nanotubes, the world's darkest known substance, to make an ultraefficient, ...
Analysis of Greenland ice cores adds to historical record and provide glimpse into climate's future
A new study that provides surprising details on changes in Earth's climate from more than 100,000 years ago indicates that the last interglacial--the period between "ice ages"--was warmer than previously thought and may be a good analog for future climate, as greenhouse gases increase in the atmosphere and global temperatures rise. The research findings also indicate that melting of the massive West Antarctic ice sheet may have contributed more to sea-level rise at that time than melting of the Greenland ice sheet. The new results from the North Greenland Eemian Ice ...
Emotional stress reduces effectiveness of prostate cancer therapies in animal model
WINSTON-SALEM, N.C. – Jan. 25, 2013 – Not surprisingly, a cancer diagnosis creates stress. And patients with prostate cancer show higher levels of anxiety compared to other cancer patients. A new study by researchers at Wake Forest Baptist Medical Center indicates that stress is not just an emotional side effect of the diagnosis; it also can reduce the effectiveness of prostate cancer drugs and accelerate the development of prostate cancer. The findings are published in the February issue of the Journal of Clinical Investigation. The Wake Forest Baptist team, headed ...