Physiological and Biochemical Changes during Moisture Stress in Banana

Present investigation was carried out to study the physiological and biochemical changes during moisture stress by identifying two contrasting genotypes from earliar studies i.e. M. acuminata. ssp burmaniceoides commonly recognised as 'Calcutta-4' belonging to AA genomic group and 'Bee hee kela' belonging to BB genomic group were used. The per cent reduction in photosynthetic rate (P_N) between control and stressed plants was 45.28 (%) for 'Calcutta-4' and 36.01(%) for 'Bee hee kela', Transpiration rate (E) was 30.24 (%) for 'Calcutta-4' and 22.36 (%) for 'Bee hee kela' and Stomatal conductance (gs) was 60.30 (%) for Calcutta-4 and 56.10 (%) for 'Bee hee kela', indicating BB genotypes are tolerant to water deficit conditions. Leaf water potential (Ø) was higher in 'Bee hee kela' (BB) both in watered (-0.913 MPa) and under stress (-1.518 MPa) situations when compared with 'Calcutta-4' (AA) control (-1.35 Mpa) and stressed (-1.824 MPa) plants. Malondialdehyde content was estimated to be high in 'Calcutta-4' than that of 'Bee hee kela' indicating higher degree of membrane damage in Calcutta-4. The two antioxidant enzymes namely Super oxide dismutase (SOD) and Catalase activities were found to be higher in Bee hee kela stressed samples than 'Calcutta- 4' indicating better oxidative damage withstanding capacity. 'Bee hee kela' (BB) showed higher Ø, gs, and antioxidant enzyme (SOD and Catalase) activities. 'Bee hee kela' genotype is more drought tolerant than 'Calcutta-4'. Identified drought tolerant genotype can be further used as a donor for drought tolerance.