Germinative energy of Eucalyptus obliqua seed.  A. Ashton.  April 2004.  10pp. (unpubl.)

SUMMARY

This experiment was conducted to determine if Eucalyptus obliqua seed with low germinative energy, as determined in the laboratory, performed as well in both the glasshouse and field as seed with a high germinative energy. This work follows on from previous inconclusive studies in Eucalyptus regnans.

The results from this study are summarised as follows:

• In the glasshouse the lower germinative energy seed lot was much slower to germinate than the other seed lots. This corresponded well with the laboratory testing result.
• In the field however, the low germinative energy seed lot performed as well as the other seed lots, with similar germination patterns found for all seed lots, regardless of the germinative energy found in the routine laboratory testing.

Problems were again experienced with obtaining a consistent germinative energy measure in the laboratory. Until such time as this variation can be minimised it will be difficult to quantify the field performance of seed in relation to its laboratory performance.

It is possible that other measures of seed vigour, such as electrical conductivity or chlorophyll fluorescence which have been successfully used in other species, may be more effective predictors of field performance in eucalypts than the germinative energy measure currently used.