Yield benefit and underlying cost of insect-resistance transgenic rice: Implication
in breeding and deploying transgenic crops
The rapid development of transgenic biotechnology has greatly promoted the commercialization of
genetically modified (GM) crops including the insect-resistant crops worldwide. Apart from the enormous
yield benefits brought by the GM crops, the cryptic fitness cost associated with transgenes has
also been detected under experimental conditions although it is considered to be rare. To estimate the
yield benefit and cost of insect-resistant GM rice, we studied field performances of three insect-resistant
GM rice lines, involving their non-GM parental variety as comparison. Great benefits as estimated by
the yield-related traits were observed in the GM rice lines when high insect pressure was recorded, but
a cryptic yield loss was detected when the level of insect pressure was extremely low. Given the fact
that cryptic yield loss presented in the GM rice lines under the low insect pressure, a strategic field
deployment should be required when insect-resistant GM rice are commercialized to circumvent the
unnecessary yield losses. This is probably true for other insect-resistant GM crops. Effective biotechnology
and breeding measures are also needed to particularly minimize the potential underlying cost of an
insect-resistance transgene before commercial production of the GM crops.