Flood-tolerant paddy likely to debut in Karnataka

A new paddy variety that can withstand submergence for more than two weeks has completed a round of successful trial at the University of Agriculture Sciences in Bangalore in this kharif season. Promising results have buoyed the researchers hope that soon it will be in farmers’ field.

Samba Mahsuri-Sub1, dubbed as the best bet in flash floods in peninsular India, is same as the popular Samba Mahsuri barring for the presence of Sub1 gene, isolated from a wild flood-tolerant paddy in Orissa. Because of the gene, the paddy can tolerate flash flood up to two weeks, whereas normal Samba Mahsuri will die after four days of submergence. Still the yield would be comparable.

“Samba Mahsuri is the most popular paddy variety of Andhra Pradesh, Karnataka and Tamil Nadu. When released for the farmers, the price of the flood-tolerant version will be same as the regular one as no intellectual property rights issue are involved,” Umesh Singh, South Asia regional project coordinator of the International Rice Research Institute (IRRI) in Manila told Deccan Herald.

Using the standard back-crossing method, the Sub1 gene was earlier introduced in another popular paddy variety, Swarna, cultivated in the paddy zones of northern and eastern India. Released in August 2009, it is the first submergence-tolerant, high-yielding paddy variety in India.

And it was a runaway success with farmers in flood-prone areas cultivating it on 12 million hectares of land. The submergence tolerance of Swarna-Sub1 is better than Samba Mahsuri-Sub1.  Asked to compare between the two varieties, Singh said while Swarna-Sub1 has good grain quality, Samba Mahsuri-Sub1 has better parental lines. Swarna is higher yielding but Samba Mahsuri fetches higher market price.

Sub1 varieties are ideal for flash flood where water recedes after 14 to 17 days. If water-logged conditions (more than 30 cm of water) persists after 17 days these varieties will not perform well. Sub1 varieties stop growing and conserve their energy once they are under water. They survive longer than normal paddy and once water recedes, the regeneration in these varieties is very fast.

Seeds are now being multiplied by industry, institution and voluntary organisations. Close to 250 tonnes of seeds will be ready for Indian farmers as Samba Mahsuri-Sub1 is slated to be released in many states in 2011 along with Bangladesh and Nepal, where floods are a perennial problem.

IRRI’s submergence-tolerant rice varieties have better yields than Indian Council of Agriculture Research’s “deep water paddy” and “boat paddy”.

Deep water paddy has SNORKEL gene, which lets it grow along with rising water level up to or more than 3 metres. In this process they loose a lot of energy and ultimately become low yielding, explained Singh.