Horticulturist Tracie Matsumoto collects a sample
from a longan tree to isolate the genes involved in flowering. Click the
image for more information about it.
and Longan Harvests Predictable
By Marcia Wood
September 22, 2004
Beneath the thin, crisp peel of an
exotic tropical lychee, sweet, delicious fruit is ready to eat. To growers in
Hawaii, however, lychee and its smaller cousin, longan, present a problem.
Harvests are unpredictable, yielding too much fruit one year and too little the
Studies led by Agricultural Research
Service horticulturist Tracie Matsumoto at the agency's U.S.
Pacific Basin Agricultural
Research Center in Hilo, on Hawaii Island, may resolve the problem. That
would be a boon not only for Hawaii's growers, but also for shoppers in Hawaii
and elsewhere who simply can't get enough of these delectable fruits.
Matsumoto's research is a fusion of old and new. Research elsewhere has
shown that a compound in Chinese firecrackers, which have been used for
hundreds of years at religious ceremonies or other special events, triggers
longan trees to flower and bear fruit. That happens--even out of season--to
trees growing where these events take place, such as at a temple.
In Matsumoto's research, the firecracker finding fits neatly with new
discoveries from plant geneticists. Those scientists, who are investigating the
genetic makeup of thale cress, or Arabidopsis thaliana--the "lab
rat" of contemporary plant genetic research--have discovered that a gene
called FLC can block flowering, but is typically suppressed by other
Matsumoto wants to see if lychee or longan have an anti-flowering gene, or
genes, similar to FLC. If they do, she'll next determine if the culprit
genes can be squelched by applying a less-explosive version of the firecracker
Matsumoto estimates that the first phase of the research--in which she'll
determine if lychee or longan has an FLC-like anti-flowering gene--could
be completed in about three to four years.
ARS is the chief scientific research agency of the
U.S. Department of Agriculture.