Photoperiod sensitivity of local millet and sorghum varieties in West Africa

Abstract

• Millet and sorghum grown in West Africa showed a strong response to daylength and photoperiod.• The photoperiod response was not only related to the latitude of origin but also the capability of lowlands to maintain soil moisture.• The critical photoperiod for millet and sorghum ranged from 13 to 13.35 hrs.• The photoperiod sensitivity for millet and sorghum ranged from 142 to 6,184 growing degree days (GDD h−1) per hour of photoperiod extension