Effect of Accelerated Aging Process on Seed Quality and Biochemical Changes in Sweet Pepper (Capsicum annuum Linn.) Seeds

Seed deterioration during storage is a complex physiological and biochemical process leading to loss of germination ability. This study focuses on seed germination and biochemical changes during an artificially accelerated aging process in sweet pepper (Capsicum annuum Linn.) seeds. The sweet pepper seeds were incubated at 42C and 100% relative humidity for 0, 5, 10, 15, 20, 25 and 30 days. The results showed that germination ability in terms of percentage of Emergence Radical (ER%) decreased and exhibited significantly different levels (p<0.01) with in all different accelerated aging times. The critical period for rapid decrease in percentage of ER is 20 days of aging time. The electrolytes leaked K+, Na+, Ca2+ and Mg2+, including Electrical Conductivity (EC) were determined in 24 h soaked seed solution with distilled water. The EC, K+, Na+, Ca2+ and Mg2+ concentrations were decreased during 5 to 10 days of aging time and increased in soaked seed solution during 10-30 days of aging time. The decrease in germination ability was well correlated with increase in membrane deterioration, as assayed by electrical conductivity and electrolyte leakage in soaked seed. Malondialdehyde (MDA) was the major product of lipid peroxidation which its concentration was rapidly increased in sweet pepper seed from 0 to 75 mg g-1 within 10 days of accelerated aging time. This phenomenon was associated with an increase in total antioxidant activity when aging was carried on 0-10 days. The peroxidation reaction of fatty acid in the cell impact in germination ability and some biochemical parameters related to membrane deterioration and loss of membrane integrity.