CUU LONG DELTA — Rice-shrimp farmers in the Cuu Long (Mekong) Delta, who have begun planting the rice crop, are facing the usual shortage of saline-resistant rice varieties.
Farmers choose them since farming shrimp in between rice crops turns their fields saline.
In Kien Giang, Ca Mau, and Bac Lieu provinces, which have the largest areas of rice fields where shrimp is also farmed, the paddies have been drained off the salt water and farmers are waiting for rains to flush the residual salinity.
Nguyen Huy Thong, a farmer in Ca Mau's Thoi Binh District, said: "This area has adopted rice-shrimp farming for the last 10 years, so farmers have to plant saline-resistant rice."
"But the supply of these varieties is still limited, and farmers often face a shortage.
"Farmers sometimes have to deposit money with seed shops to get saline-resistant rice varieties."
Tran Van Dung, deputy director of the Thoi Binh District People's Committee, said farmers here have sown more than 800ha of seedlings for transplant in the district's 25,000ha of rice fields.
This year besides long-term rice varieties such as Tep Hanh, Mot Bui Do, farmers have also opted for new short-term varieties that can tolerate salinity rates of 0.4-0.6 per cent, he said.
Long-term varieties – which are tastier, and, hence, fetch more money – have a maturity period of up to six months, and short-term varieties mature in around half that period.
In Kien Giang Province's U Minh Thuong area, which has the largest rice-shrimp farming area in the province, many farmers have switched to short-term varieties this year.
Le Van Hien, who owns 3ha in An Minh District's Dong Hoa Commune, said: "Previously I grew long-term rice varieties, but in the last two years I switched to the short-term ST5 strain."
Cultivating short-term varieties requires less labour compared to long-term ones which require seedlings to be transplanted, he explained.
"Besides the ability to resist salinity, the ST5 variety offers high yields and is delicious and easy to sell.
"However, it is difficult to get this seed for this crop."
The strain was created in Soc Trang Province.
Trong, who has a seeds shop in Kien Giang's U Minh Thuong District, said his supplier has had no ST5 for about a month, and its harvest is only just beginning in Soc Trang.
Many farmers have also planted hybrids like B-TE1, PAC 807, HR 182, which are also suitable for growing in rice-shrimp fields.
Nguyen Trung Dien, director of the Kien Giang Agriculture Fisheries and Forestry Breeding Centre, said the centre has researched and created saline-resistant rice varieties in the past few years.
Its GKG 1, for instance, can tolerate more than 0.4 per cent salinity, he said.
The Kien Giang Department of Agriculture and Rural Development has warned farmers to thoroughly flush their fields of salinity after harvesting shrimp, using both rainwater and water from the canal to wash them two or three times over a period of at least one month before planting.
It has also encouraged farmers to switch from some long-term varieties that are of low quality and yield and disease-prone to short-term varieties of high quality and yield. — VNS