SOIL IMPEDANCE AND ITS EFFECT ON CALABRESE EMERGENCE

The level and rate of seedling emergence of calabrese were found to be negatively correlated with the work done in penetrating the top 15 mm of a sandy loam soil, using a load transducer penetrometer to measure the work done.
The effect was recorded whether impedance was caused by rainfall or mechanical compaction.
When a crust was present, emergence level showed negative correlation with peak penetration force.
Light compaction of moist soil reduced emergence and heavier compaction reduced emergence even when the soil was dry.
In a fine sandy soil, 5 mm of simulated rainfall caused delayed emergence of calabrese sown at 22mm and reduced emergence when sown at 27mm.
The results indicate that soil impedance may be of wider importance than generally recognised in affecting level, rate and uniformity of emergence.

Symposium on the Timing of Field vegetable Production

Shiela M. Royle, T.W. Hegarty

https://doi.org/10.17660/ActaHortic.1978.72.28