Agriculture Reference
In-Depth Information
effectively achieved reduced oxidation by silencing the endogenous PPO gene (Carter
2012). The second improved quality product was a potato submitted by JR Simplot.
Their potato with three specific modifications for quality improvement, was submit-
ted for petition for determination of nonregulated status in 2013. It uses what it terms
innate technology , basically utilizing RNA interference (RNAi) to silence genes related
to black-spot bruising and to reduce asparagine and sugars in tubers.
One example of widespread success in the use of biotechnology to reduce the impact
of biotic stress and enhance sustainability is India's experience with Bt cotton. The
Maharashtra Seed Company (Mahyco) developed transgenic hybrids in partnership
with Monsanto, utilizing a Cry1Ac transgene to produce hybrids expressing a protein
lethal to the major pest of cotton:  the bollworm. The number of approved cultivars
expanded from three in 2002 to over a thousand by 2012. Farmer-bred illegal varieties
have proliferated underground as well. Adoption has increased to over 90% of cotton
acreage by 2012, with an increasing share of the market going to stacked gene technology
(Herring and Rao 2012). Between 2002 and 2008, Bt cotton generated economic benefits
for farmers valued at US$5.1 billion, halved insecticide requirements, contributed to the
doubling of yield, and transformed India from a cotton importer to a major exporter
(Choudhary and Gaur 2008, 2010). India has become the number one exporter of cot-
ton globally as well as the second largest cotton producer in the world. A number of
multi-institutional projects have been launched in India, including the development of
transgenics for resistance to geminiviruses in cotton, mungbean, and tomato; resistance
to rice tungro disease; development of a nutritionally enhanced potato with a balanced
amino acid composition; and development of molecular methods for heterosis breed-
ing. Other transgenic crops await approval for commercial cultivation, such as trans-
genic herbicide-tolerant mustard hybrids and nutritionally enhanced potato varieties.
Despite the success of Bt cotton, further implementation of the Government of India's
strategy for biotechnology has been restricted, however, by factors considered in the
final section of this chapter (Bricknel 2010).
Work on biotic stress tolerance is expanding to multitiered control systems. This in
theory serves a double advantage, primarily expanding the effectiveness of the broad
based resistance events but also allowing more effective management of the resistance
trait since there is less selective pressure when genes are stacked. Focus on biotic stress,
especially in pest control, will continue, but interest in abiotic stress tolerance is gaining
prominence as external pressures from climate change become manifest.
Climate Change and
Agriculture: Green Biotechnology
The meta-issue of climate change overlays many of the emergent individual plant breed-
ing efforts. It poses significant challenges in terms of available agricultural land and
 
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