Comparative transcriptome analysis provides insight into the molecular mechanisms of long-day photoperiod in .

Unlabelled: , is commonly cultivated as a vegetable in tropical and subtropical regions because of nutritional and medicinal benefits of its fruits, immature pods, leaves, and flowers. Flowering at the right time is one of the important traits for crop yield in . Under normal conditions, photoperiod is one of the key factors in determining when plant flower. However, the molecular mechanism underlying the effects of a long-day photoperiod on is not clearly understood. In the present study, deep RNA sequencing and sugar metabolome were conducted of leaves under long-day photoperiod. As a result, differentially expressed genes were significantly associated with starch and sucrose pathway and the circadian rhythm-plant pathway. In starch and sucrose pathway, sucrose, fructose, trehalose, glucose, and maltose exhibited pronounced rhythmicity over 24 h, and (trehalose-6-phosphate synthase) genes constituted key regulatory genes. In an overexpression line hosting the or genes, flowering occurred earlier under a short-day photoperiod. These results will support molecular breeding of and may help clarify to genetic architecture of long-day photoperiod related traits.

Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01186-4.