d><p>a numeric vector</p>
</dd>
<dt>ct</dt><dd><p>concentration-time</p>
</dd>
<dt>Cultivar</dt><dd><p>a factor with levels <code>Pacific Rose</code> <code>BRAEBURN</code> <code>Fuji</code> <code>GRANNY</code> <code>Gala</code> <code>ROYAL</code> <code>Red Delicious</code> <code>Splendour</code></p>
</dd>
<dt>Dose</dt><dd><p>injected dose of methyl bromide</p>
</dd>
<dt>rep</dt><dd><p>replicate number, within Cultivar and year</p>
</dd>
<dt>year</dt><dd><p>a factor with levels <code>1988</code> <code>1989</