Differences in rice cultivars for growth and phosphorus acquisition from rock phosphate and mono-ammonium phosphate sources

Exploitation of genetic variations among crop species and genotypes for increased phosphorus (P) efficiency can sustain crop yields in soils low in available P. Five rice cultivars (viz. Basmati-385, Basmati-370, Super Basmati, Shaheen Basmati & NIAB-IR9) were evaluated for their growth response and P uptake from phosphate rock (PR) and mono-ammonium phosphate (MAP) in hydroponics. Shoot and root dry matter production, P concentration differed significantly (p<0.01) among cultivars grown either with PR and MAP. However, plants grown with MAP accumulated higher biomass and P contents than grown with PR. Phosphorus contents in plants grown with PR ranged between 2.20 to 5.14 mg per plant and it ranged between 19.51 and 34.82 mg per plant grown with MAP. Phosphorus utilization efficiency was maximum in NIAB-IR9, Basmati-370 and Basmati-385 when grown with PR, while in plants grown with MAP, Super Basmati, Basmati-385 and NIAB-IR9 exhibited maximum P use efficiency. Cultivars Basmati-385 and Basmati-370 produced higher biomass as well as P uptake. Further studies on P efficiency traits of these cultivars such as root morphological and physiological processes may improve our knowledge on P use efficiency in rice.