ABSTRACT
Breaking of seed dormancy of wild oat (Avena fatua L.) with ammonia did not influence the activity of the pentose phosphate pathway enzymes glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH). Alpha-amylase synthesis in de-embryonated endosperm halves which had been treated with ammonia and subsequently washed under tap water for 48h, increased five-fold. Washing did not influence alpha-amylase production of untreated endosperm halves.
Ammonia treatment led to an 81% increase in respiration in incubating seeds. This increase in respiration was partially inhibited by salicylic hydroxamic acid (SHAM). It is postulated that loss of dormancy induced by treatment with ammonia is associated with the induction of increased respiratory activity. There is, however, no conclusive evidence that this increased respiratory activity is via the alternative respiratory pathway.
