Evaluating different artificial ageing techniques and variability in tolerance to ageing of seeds of Brassica spp. and Eruca sativa

Abstract

The seeds of B. juncea, B. napus, B. rapa and Eruca sativa, a related genus of Brassica sp., were
subjected to different ageing treatments including rapid ageing through immersion into hot water at 58±2oC,
controlled deterioration by raising the seed moisture content to 15% at 40±2oC, and subjecting the seeds to
higher relative humidity of 95% using saturated solution of Potassium nitrate at 40±2oC. Each of the
accession was studied for physiological factors like germination percentage, mean germination time, and
vigour index which declined with all the ageing treatments. Maximum decline was shown by accessions of
B. napus and E. sativa. The accessions of B. juncea and B. rapa were found to be better performers as
compared to the accessions of B. napus and E. sativa. The biochemical assays like electrical conductivity
and lipid peroxidation, increased with the progress of deterioration. Decline in enzyme activity of peroxidase
and catalases were observed, and these enzymes become non-functional when the seeds were dead. All the
accessions showed a coherent response to ageing treatments irrespective of the species under study. Hot
water ageing was a rapid method of ageing but controlled deterioration by equilibrating the seed moisture to
a higher level (15%) and subjecting to elevated temperature of 40±2oC (controlled deterioration) was more
reliable method of accelerated ageing technique for predicting the storability of seeds of Brassica and related
genera.