昼长 meaning in English

daylength

In summer the days are long
夏季昼长。
The promotion effects is stronger with the increase of number of photoperiods , which suggests that the flowering process in salicornia bigelovii torr . is not a " all or none " process . treated with 13 - 18 photoperiods and then transposed to long - daylength ( 17h light / d ) , some of the inflorescences of the plants reversed to vegetative condition , which means flowering reversion occurred ( which belongs to inflorescence reversion type )
毕氏海蓬子开花的临界日长为15小时，济南地区最大昼长在6月23日，为14小时40分，并没有超过其临界日长，但处于自然日照条件下的毕氏海蓬子直至7月25日才形成花序，在此之前一直处于营养生长状态，可能这个阶段是成花物质积累的阶段，当成花物质数量积累足够多时，才可促进花序形成和导致开花。