KLANG: A salty threat is slowly making its way into some of the nation’s padi fields, which may create food security issues in future if not properly addressed.
Researchers say seawater seepage into padi fields has so far been detected in coastal areas and rice granaries in Kerian and Kuala Kedah in Kedah; some areas in Kelantan; Rompin in Pahang; and Sabak Bernam in Selangor.
Penang Institute’s Heritage and Urban Studies head Prof Datuk Dr Zulfigar Yasin said saline intrusion into padi fields would adversely affect the growth of the plant and reduce yield.
“Higher concentrations will lead to plant death, with young plants being more susceptible to increasing salt in the water,” said Prof Zulfigar, who is a marine environmental scientist.
He said seawater contains a high amount of salt and it takes a mere 0.3% concentration of seawater to kill padi plants.
He added that seawater usually makes its way into padi fields through seepage that occurs in coastal areas.
“Most padi growing areas are on the coastal lowland next to the sea. When there are tidal flows at river entrances, as well as during high tide, seawater may intrude significantly into the hinterland,” he said.
He also said coastal erosion which damages barriers that separate sea from land, as well as the destruction of coastal vegetation due to unplanned development, would also result in seawater seepage into padi fields.
“These risks are expected to increase in the future as storms rise in intensity and frequency on our coasts.
“Greater intrusion of saltwater into many coastal areas on a bigger scale is anticipated with the rising levels of the sea as a result of climate change.
“This rise will overcome coastal barriers and as such, breaches will result in larger amounts of seawater entering padi growing areas.
“That is why it is crucial for sea-facing barriers to be regularly inspected to detect seawater intrusion,” he added.
Prof Zulfigar said what was needed to battle seawater damage to padi fields were the construction of sea walls and embankments, as well as protection or improvement of natural vegetation such as mangroves, among others.
Universiti Putra Malaysia Agriculture Faculty’s Prof Dr Mohd Rafii Yusop said efforts were underway by relevant agencies and academic institutions to develop a saltwater-resistant variety of padi.
“I believe this new saltwater- resistant variety will be ready for cultivation in about two years,” he said.
According to Prof Mohd Rafii, a saltwater-resistant variety was already available in China but there was a lot of red tape if the padi seeds were to be imported for local cultivation.
“Our regulations require the seeds to be quarantined for two planting seasons, and tests have to be carried out to determine that the imported variety will not bring in any diseases,” he said, adding that it would take about two years to get the green light.
Dr Noraziyah Abd Aziz, who is with Universiti Kebangsaan Malaysia’s (UKM) Department of Biological Sciences and Biotechnology, said most of the modern rice varieties in Malaysia were susceptible to salinity and other “abiotic” (non-living or non-organic) stress.
“Researchers here and around the world are focusing on identifying salinity-tolerant rice varieties.
“Previous studies have indicated that traditional varieties such as Pokkali and Nona Bokra were salinity tolerant, but these have low yield,” she said.
Noraziyah also said extensive work was being carried out locally to identify padi genes that were salinity tolerant and so far, several have been identified.
“Efforts are being made to transfer these genes into salinity- susceptible mega-varieties via conventional or marker-assisted breeding,” she said, adding that other methods such as mutational and genetic engineering were also being used.
“Researchers from UKM, the Malaysia Nuclear Agency and International Islamic University have successfully developed salinity-tolerant rice breeding lines through marker assisted breeding and mutational breeding,” she added.
