Figure 3. Summary of the effects of heat on yield traits of rice during different reproductive stages.

R0: panicle development has initiated; R1: panicle branches have formed; R2: the flag leaf collar has formed; R3: the panicle has emerged from the boot; R4: one or more florets on the main stem panicle has reached anthesis; R5: at least one caryopsis on the main stem panicle has elongation to the end of the hull; R6: at least one caryopsis on the main stem panicle has elongated to the end of the hull; R7: at least one grain on the main stem panicle has a yellow hull; R8: at least one grain on the main stem panicle has a brown hull; and R9: all grains that reached R6 have brown hulls. The illustrations of the reproductive stages with morphological markers are adapted from those by Counce, Keisling & Mitchell (2000).