TRACE ELEMENTS DISTRIBUTION IN HEIRLOOM PADDY PANDASAN CULTIVATED UNDER FIELD CONDITIONS OF DRY AND WET SOIL

Abstract

Trace elements phytoavailability depends on the physical and chemical propertiesof soil. At the Crocker range of West Coast Sabah, Malaysia, the Pandasan paddyvariety can be cultivated as flooded rice paddies or upland rice on acidic soil.Pandasan paddy samples were collected in Kiulu subdistrict from traditionalfarmer at two different locations. Available sources of trace elements were fromweathering, fertilizers and pesticides. Soil and plant samples were collected aftertwo months of seed sowing and during harvest season which was five months oldfor heavy metal analysis by inductively coupled plasma optical emissionspectrometry (ICP-OES). Translocation factor of arsenic from root to grainindicated this trace element was very mobile in Pandasan paddy cultivated at drysoil compared to wet soil followed by zinc. Although, cadmium was not detected inpaddy cultivated at flooded field for both, soil and plant, cadmium was detected insoil and plant roots cultivated in dry condition. Enrichment factor results suggestedthat Pandasan plant cultivated on dry soil was only a good bioindicator for leadand zinc. Pandasan grain was rich with iron followed by zinc. Selected heavymetals accumulation in Pandasan grain cultivated in flooded field did not exceededthe permissible limit of Malaysia Food Regulation 1985. However arsenic andplumbum concentration in Pandasan grain harvested from dry soil exceeded thepermissible limit of Malaysia Food Regulation 1985. Health risk of heavy metalstoxicity can be reduced if Pandasan paddy is cultivated in flooded field comparedto dry soil.