Rice institute introduces salt-tolerant variety
Wednesday, April 17, 2013
LAHORE: Farmers are set to reclaim salt-ravaged land, thanks to a single rice plant born of two unlikely parents that is spawning a new generation of rice that has double the salinity tolerance, International Rice Research Institute (IRRI) said on Tuesday.
“This will make saline-stricken rice farms in coastal areas usable,” said lead scientist Dr Kshirod Jena of the Irri. “These farmlands are usually abandoned by coastal farmers because the encroaching seawater.” Unlike regular rice, the new rice line can expel salt it takes from the soil into the air through salt glands on its leaves, he said.
The new rice was bred through successful crossing of two different rice parents – the exotic wild rice species Oryza coarctata and rice variety IR56 of the cultivated rice species O. sativa. What is extra-special about this breakthrough is that O. coarctata is extremely difficult to cross with cultivated rice varieties. “When we cross two types of rice with genomes so far off from each other in the genome sequence, the resulting embryo tends to abort itself,” Dr Jena said. “We’ve been trying to backcross these types of inter-specific hybrids since the mid-1990s.”
Dr Jena’s team successfully rescued three embryos out of 34,000 crosses. Out of these three, one plant survived to give scientists enough material to backcross and make sure that only the desired trait — double salt-tolerance — is acquired from the wild species.
The reason scientists did not give up on crossing the two types of rice was because O. coarctata is a special type of rice that grows in brackish, salty water – which makes it highly resistant to saltiness in the soil. According to Dr Jena, O. coarctata can tolerate a higher salinity concentration (similar to that of seawater), whereas current salinity-tolerant rice varieties can cope with only half that concentration. However, O. coarctata is unsuitable for the production of edible rice. Source The NEWS