Effect of a switch in photoperiod on the reproductive development of temperate hybrids of maize.

The reaction of maize to a switch in light phase was investigated in 3 phytotron experiments. Number of leaves was increased by a long-day phase (20 h) before tassel initiation but was not affected thereafter. Reproductive development was delayed by long days before tassel initiation and slowed down by long days after tassel initiation but ear development was affected more than tassel development. The time lag between anthesis and silking increased when short days (12 h) were followed by long days and the opposite was true when long days were followed by short days. Direct responses to photoperiod such as number of leaves and tassel branches occurred over a rather short time. Indirect effects such as area of leaves, ht. of plant and length of the ear shoot were max. when daylength no longer affected the number of leaves. (Abstract retrieved from CAB Abstracts by CABI’s permission