Down-Regulation of Carbohydrate Metabolic Pathway Genes Lowers Sucrose and Starch Content in Chickpea Leaves Under High Temperature Stress

High temperature (HT) lowers carbohydrate content in leaves but no information is available on HT-induced reprogramming of transcription of carbohydrate metabolism genes in chickpea. Impact of HT (35 °C) on plant growth, starch content and transcription of sucrose and starch metabolism genes were studied in leaves of chickpea. HT caused leaf chlorosis, flower abortion, reduced seed filling and lowered starch content. The short-term (2 h) as well as long-term (72 h) HT exposure down-regulated all the sucrose and starch metabolism genes except isoamylase 3 and β-amylase 1 . The study suggested that HT-induced disruption of sucrose and starch metabolism resulted from down-regulation of carbohydrate metabolic pathway genes. Over-expression of β-amylase 1 and no change in expression of isoamylase 3 suggested increased accumulation of maltose under prolonged heat stress.