Blind graduate, Dr Ashley Subbiah, received a standing ovation after he was awarded his PhD in Biology at the Life Sciences graduation ceremony of the College of Agriculture, Engineering and Science.

Subbiah’s thesis quantified desiccation sensitivity in recalcitrant seeds and was supervised by Professor Norman Pammenter, Professor Sershen Naidoo, Dr Boby Varghese and the late Professor Pat Berjak.

Recalcitrant seeds are seeds that do not survive drying and freezing during ex-situ (off-site) conservation and vice-versa. By and large, these seeds cannot resist the effects of drying or temperatures less than 10°C; thus they cannot be stored for long periods like orthodox seeds because they can lose their viability.

‘Many plant species in the tropics and subtropics produce recalcitrant seeds, which unlike orthodox types are desiccation sensitive and cannot be stored using conventional methods,’ said his supervisors.

‘Subbiah’s study provided new insights into the physiological and evolutionary factors governing seed recalcitrance and offered valuable quantitative tools for seed conservation.

‘This multidisciplinary study represents a triumph not just for Ashley, but also for students with disabilities across South Africa.’

Words: Sally Frost

Photograph: Abhi Indrarajan