The effect of various pre-treatments and their interaction with temperature on cumulative percentage and the
rate of germination were evaluated for Digitaria nuda. Stored and fresh seeds were pre-treated with either
0.02 M KNO3, soaked in water for 24 h (priming), sterilized with 0.5% NaOCl or heat treated at 60 °C. Seeds
were germinated at constant temperatures of 25 and 30 °C and fluctuating temperature regimes of 25/10 and
30/15 °C. The effect of pre-chilling on germination of stored and fresh seed was evaluated at 30/15 °C, and
seed emergence in two soil types at different burial depths (0, 0.5, 1, 2, 3, 4, 5 and 6 cm) was also determined.
The pre-treatment of stored seed with KNO3 resulted in the highest germination percentage (100%), whereas
the pre-treatment of fresh seed with water for 24 h gave the best germination (99%), at constant temperatures
of 25 and 30 °C. Pre-chilling of seed increased germination by more than 30%. Emergence from clay loam soil
was greater compared with the emergence from sandy loamsoil. Total seedling emergence decreased exponentially
with increasing burial depths with only 5% of seed germinating from a burial depth of 6 cm. Results from
this study showed that germination requirements are species specific and knowledge of factors influencing
germination and emergence of grassweed seed can assist in predicting flushes in emergence allowing producers
to implement control practices more effectively.