Measurement of BPH weight gain and honeydew excretion
BPH weight gain and honeydew excretion measurements were conducted
according to the method described by Yang et al. (2020). Specifically,
one pre-weighed fourth to fifth instar female BPH was enclosed in a
pre-weighed rectangular parafilm bag (3.5 cm × 3 cm) with a pipette,
which was fastened to the shoots of test plants (30 days). Two bags for
each plant and eight bags for each line of OE, knockout, or NIP plants
were surveyed. After 48 h of BPH treatment, the bags were removed and
the total weight of the bag enclosing honeydew excretion was measured.
The BPH and bags with honeydew excretion were then weighed separately.
Finally, the weights of the BPH and honeydew excretion were calculated,
and the test was repeated three times.