Plant Biotechnology and Genetics: Principles, Techniques and Applications

(Brent) #1

to Bt pollen, risk of Bt pollen to monarch butterflies was determined to be negligible
(Sears et al. 2001) (ERA step 4). Again, the amount of Bt maize pollen force-fed to
monarch butterfly larvae was much higher than in field exposures, therefore indicating over-
estimation of risks. It is interesting to note here that the degree of hazard would not change


Figure 13.3.Weed strip of white mustard (Sinapis alba) in a cornfield for collection of butterfly
larvae on top of weed leaves.


Figure 13.4.Collection of butterfly larvae was done by dislodging them into a cotton tray.
Taxonomic knowledge and experience is needed for identifying the right caterpillar species
because of the small size of the larvae.


318 FIELD TESTING OF TRANSGENIC PLANTS
Free download pdf