Respiration and activity of respiratory enzymes in okra (Abelmoschus esculentus ) under seasonal environmental conditions of West Bengal, India

Abelmoschus esculentus var. Parbani Kranti (okra) was studied in summer, rainy and winter seasons in pot culture and 28 and 58 day old leaves were collected to study the seasonal environmental empact on their respiratory metabolism. The rate of respiration along with the activity of three respiratory enzymes viz. fructose 1,6- bisphosphate aldolase, succinate dehydrogenase, glucose-6-phosphate dehydrogenase was highest in the summer season. Rainy and winter seasons showed comparatively low respiration rate and enzyme activity. Respiration rate and activity of the three above enzymes were also higher in the younger leaf samples, 28 days after sowing (DAS) as compared to the older leaf samples, 58 DAS in all the three seasons in the order of summer> rainy> winter. Since respiratory metabolism is an index of energy demand, summer is therefore a season of higher physiological activity as compared to rainy and winter. The present study indicates the alteration in respiratory activity in different seasons and developmental stages in okra, basides giving an idea of the energy demand under these changing environmental conditions, which can in turn, by correlated with the physiological behaviour of the plant.