Acclimation of clusterbean cotyledon to UV-B radiation in the presence of UV-A: partial restoration of photosynthetic energy balance and redox homeostasis

作者：Joshi Padmanava^*; Gartia Sasmita; Pradhan Manoj Kumar; Panigrahi Srikanta; Nayak Lalitendu; Biswal Basanti

来源：Acta Physiologiae Plantarum, 2013, 35(7): 2323-2328.

DOI：10.1007/s11738-013-1245-6

• Chlorophyll fluorescence induction
• Photosystem II
• Photostasis
• Redox homeostasis
• Thermoluminescence
• Thylakoid

The photosynthetic responses of clusterbean (Cyamopsis tetraganoloba) cotyledons exposed to UV-A, UV-B or UV-A + UV-B radiation for 1 h daily until day 10 have been compared. The loss in the rate of O-2 evolution and CO2 assimilation (P (n)) are incommensurate with each other in both UV-A and UV-B exposed samples indicating the occurrence of loss in photostasis of photosynthesis by these two radiation bands. The alteration in redox status of Q (A) further suggests about a loss in redox homeostasis in the photosynthetic electron transport chain. However, both photochemical efficiency of PS II and P (n) are well maintained in UV-A + UV-B exposed cotyledons in spite of reduction in water-use efficiency. The acclimatization of clusterbean cotyledon to UV-B radiation in the presence of UV-A has been attributed to accumulation of flavonoids, increase in stomatal conductance (g (s)) and reduction in functional size of PS II.

• 出版日期2013-7