Crop genetic improvement to enhance
responses to insect attack
Introgression lines of wild species into crop germplasm
provide a powerful resource for bringing in the traits
required [30]. However, it is often difficult to cross crops
with wild relatives when they are distantly related and
there is the problem of ‘linkage drag’ during which
undesirable genes near the desired ones on the chromosome
are brought across [30]. GM techniques could help
solve this problem [12
,31,32
] but are not used as much
asthey could be by crop breeders due to marketing issues,
influence of pressure groups and regulatory restrictions
that make what could be an efficient process slow and
expensive.