Fungus attacks strawberries in Lam Dong, Vietnam

Fungal infections have wiped out 60 per cent of strawberry plantations around Da Lat City in the Tay Nguyen (Central Highlands) province of Lam Dong.

During the last two months, the total area under strawberries have fallen from 100ha to 40ha.

This has led to a 50 per cent drop in productivity – from 40kg per 360sq.m every two days to 20kg.

The symptoms of the disease include infected roots, withered plants and yellow leaves, said the director of the Department of Plant Protection, Nguyen Van Son.

According to tests run by the related Institute of Plant Protection in November, the fungi causing the disease are Pythium spp and Gloeosporium sp.
Pythium spp fungi live in the soil and infect the roots, preventing them from taking up water and nutrition. Gloeosporium sp fungus can proliferate in wet weather, said Son.

He also blamed the farming practices of local farmers, claiming they often used too much fertiliser and plant protection chemicals. He said this hardened the soil and increased the amount of salt in the soil.

The strawberry roots cannot go deep into the soil to take nutritional substance and then die.

"The disease decrease the strawberry areas sharply, thus the fruit prices soared," he said.

At present, strawberry price reaches VND90,000 (US$4.5) per kilo, three times higher than last year.

"Even though prices are high for the fruit, many farmers do not have enough strawberries for sale," said Son.

Nguyen Quang Thanh who lives in Ward 8 in Da Lat City owns a strawberry garden of more than 1,000m, but half have died.

"I have planted strawberries for 10 years, but this is the first time they have been hit by the disease," he said.

Now Thanh is switching to growing flowers and vegetables. His neighbours have started to grow pumpkin buds and cauliflowers.

Meanwhile, Son said his department planned to train farmers proper techniques for growing strawberry in co-operation with the Lam Dong Agricultural Technology Centre.

Farmers will be shown when and how to use fertiliser and advice on proper drainage.

After the course, the farmers will be given substances to kill the fungii in soil.