杏吧原创

PLANT breeders are hoping to prevent famine in war-ravaged Congo by stemming
the advance of a deadly new virus that attacks its staple crop, cassava.

The people of the Democratic Republic of Congo (DRC) have relied on cassava
to avoid starvation during years of civil war and misrule. Its roots are packed
with carbohydrate and its leaves are the main green vegetable eaten by the
country鈥檚 45 million people.

But the plant鈥檚 survival is threatened by a virulent new strain of the
cassava mosaic virus. The strain evolved in Uganda, where it destroyed most of
the country鈥檚 harvest, and has now entered the DRC on plants carried by
refugees.

Now Alfred Dixon of the International Institute of Tropical Agriculture in
Ibadan, Nigeria, has bred new varieties of the plant that are resistant.
Thousands of tiny plants are being shipped to the DRC this month, where they
will be distributed to farmers in a bid to halt the spread of the mosaic virus.
Dixon hopes his new varieties will be growing in 11 provinces by the end of this
year.

Cassava yields have been declining in Africa because of disease. Plant
breeders have ignored the problem because it is so difficult to grow new
varieties of cassava, says Dixon. The plant has to be bred by vegetative
propagation, which takes a long time. But it is an ideal crop for countries
racked by war. Dixon鈥檚 famine relief unit in Ibadan has successfully distributed
improved varieties to stave off hunger in Sierra Leone, Liberia and Angola.

鈥淚t will grow virtually in the bush, needs little tending and can be
harvested at any time,鈥� he says. But he warns that without continued work on
better varieties, the crop鈥攐ne of Africa鈥檚 key life supports鈥攎ay be
doomed.