Common Wild Rice (Oryza rufipogon Griff.) and Some Tropical Rice (Oryza sativa, L.) Varieties Response to Inorganic Phosphorus Application

This study aimed to evaluate the effect of phosphorus on the shoot and root morphology of common wild rice (Oryza rufipogon Griff.) and tropical cultivated rice varieties (O. sativa L.) as upland rice (Sew Mae Jan) and lowland rice (KDML105, RD7 and IR68144) under 2 levels of inorganic phosphorus application (0 ppm Pi and 10 ppm Pi) 45 days after planting.It was revealed that phosphorus availability clearly affected both rice shoot and root system excepted the primary root length. The rice varieties had different numbers of leaves/plant and senescing leaves/plant, plant height, dry shoot weight and root length. Pi-dependency value showed RD 7 and O. rufipogon had responded to Pi application when leaf number and dry shoot weight accumulation were assessed. Sew Mae Jan had higher dry shoot weight than other rice varieties, but it had low tillering and responded to Pi-application compared with those varieties.