Pulsed electric field studies of bio-dielectrics

Chemical weed control accounts for oyer /spl Bscr/ in costs to the American farmer. Non-chemical alternatives offer many advantages such as protecting the environment and safety for applicators. Studies have shown that high voltage, pulsed electric field (PEF) treatment of biodielectrics is an effective method to inactivate micro-organisms and bacteria. Therefore, the PEF technology might be used as an effective alternative to chemical weed control. In this work, we have studied the breakdown characteristics of weed seeds using single and repetitive pulsed electric fields. Breakdown of seeds as a function of various parameters of the pulsed system such as its duration, rise/fall time, repetition rate, and field strength, are studied. Two types of weed seeds, namely yellow foxtail and smallflower morningglory, were used in the experiment. Preliminary results suggest that the PEF method can reduce the percent germination of the yellow foxtail. Conversely, the smallflower morningglory had increased percent germination. This trend is most likely due to the presence or absence of a hardened seed coat of which the smallflower morninglory possesses.