Bottlegourd Gene May Curb Cucurbit Virus
By Ann Perry
October 3, 2007
Bottlegourds have been used around
the world for food, bottles, bowls, spoons, musical instruments and even bird
houses. Now a "genetic" genie in the versatile bottlegourd may be
used to reduce virus infestation in watermelons.
Agricultural Research Service (ARS)
Ling and geneticist
Levi conduct research on plant diseases at the
Vegetable Laboratory in Charleston, S.C. They are looking for tools to
fight zucchini yellow mosaic virus (ZYMV), which infects cucurbit crops:
cucumbers, melons, pumpkins, squash, bottlegourds and watermelons.
Throughout North America, several viruses transmitted by insects, including
ZYMV, are especially troublesome to watermelons and other cucurbit crops.
Producers are anxious to find new ways of suppressing these viruses. Previous
research by other scientists suggested that bottlegourd (Lagenaria
siceraria) had some genetic resistance to ZYMV, but this research needed
Ling and Levi obtained seeds for 190 bottlegourd accessions that were
collected from different parts of the world and kept at the
Plant Genetic Resources Conservation Unit in Griffin, Ga. They raised the
seeds in their Charleston greenhouses, and then inoculated the bottlegourd
plants with ZYMV and evaluated how well they resisted the virus.
To their surprise, 36 accessions of the 190 screened33 from India
alonewere completely resistant to ZYMV infection, and another 64
accessions were partially resistant. They also found that ZYMV resistance is
heritable in crosses between different bottlegourd accessions, enabling the
development of bottlegourd varieties with enhanced virus resistance.
Popular watermelon cultivars could be grafted onto bottlegourd rootstocks
with enhanced resistance to bolster the watermelons ability to resist
ZYMV. Some watermelon growers have already been experimenting with grafting
watermelon on bottlegourd rootstocks to control soilborne diseases and to
enhance fruit production and quality.
Ling and Levis success in identifying disease-resistant bottlegourd
accessions will further efforts to find environmentally friendly ways of
controlling watermelon pathogens and pests. For producers of a U.S. commodity
worth $435 million in 2006, that would be a wish come true.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.