Answer to Question 1
Environmental conditions, crop type, stage of development, dose
concentration, method of application, volume of application, and coverage.
Answer to Question 2
Graphical tracking is used to determine when and to what extent to use
DIF for plant height control. Two curves are plotted on a graph, one showing the
minimum and the other the maximum acceptable heights for a crop over the
cropping time. Twice a week the height of the current crop is measured and also
plotted on this same graph. When the crop becomes too tall, day and night
temperatures are adjusted to give a lower DIF value which in turn lowers the rate
of increase in height. If crop height is too low the DIF value is increased until crop
height comes in line with the desired level.