Geoscience Reference
In-Depth Information
based on the expression of specific stress-related genes. Such
trait-based approaches to crop genetic enhancement have led to
genetic manipulations (through transgenic approaches), thereby
resulting in desired genotypes. Hence, research efforts in genetic
engineering are advancing so as to keep pace with predicted
environmental changes that will be more variable and stress-
ful. Climate change will also be associated with increased water
stresses in many regions due to changes in rainfall distribution
and because increased temperatures under low relative humid-
ity will result in a greater evaporative demand, thereby reducing
water use efficiency, particularly in drought-prone environments.
Bennett (2003) summarises options for water productivity
enhancement through crop breeding and biotechnology (Bt),
whereas Ortiz et al. (2007) provides an overview of transgenic
research for drought-prone environments. Innovations in crop
genetic enhancement have provided some of the best options for
farmers, especially in the developing world, to combat against
global warming, water scarcity, flooding and salinity. Genetic
enhancement of crops brings innovations to farming systems as
a result of new findings and ensuing knowledge from research.
Crop improvement has been accelerated by the genetic engi-
neering of new traits, particularly those that are not amenable to
conventional breeding. Farmers grew about 114.3 million ha of
transgenic crops in 2007 (with a growth rate of 12% vis-à-vis the
previous year).
5.5
the Indian scenario
GE crops promise to make a great, possibly indispensable,
contribution to reducing mass hunger even in adverse climatic
conditions. Yet, the development of GM (genetically modified)
crops has recently caused widespread unease in many coun-
tries. Controversies over GM crops and GM food in India have
summed up many of the issues. Maharashtra, Karnataka and
Tamil Nadu had an average of 42% increase in yield with GM
cotton in 2002, the first year of commercial GM cotton plant-
ing, but due to a severe drought in Andhra Pradesh that year,
the parental cotton plant used in the genetic-engineered vari-
ant was not well suited to the extreme drought, and hence, no
increase in yield. Drought-resistant variants were developed
with substantially reduced losses to insect predation. By 2011,
88% of Indian cotton was made GM. However, recently, the
cotton bollworm has been developing a resistance to Bt cot-
ton and the Indian Agriculture Ministry linked farmers'
