The development of NPT rice at IRRI was inspired by Donald’s (1968) ideotype breeding approach.
The goal was to develop NPT cultivars with a yield potential 20 to 25% higher than current existing semidwarf rice cultivars under a tropical environment during the dry season.
The NPT was designed based on the results of simulation modeling and the new traits were mostly morphological since they are easier to select than physiological traits in breeding programs.
The proposed NPT has a low tillering capacity (three to four tillers when direct seeded), few unproductive tillers, 200 to 250 grains per panicle,a plant height of 90 to 100 cm, thick and sturdy stems, dark green and erect leaves, a vigorous root system, 100-to 130-d growth duration, and increased harvest index .