been demonstrated in laboratory trials, but despite Bt crops being grown on more than 15 million ha worldwide, an in­crease in the frequency of resistance caused by exposure to Bt crops in the field has not yet been reported (Fox et al., 2003; Tabashnik et al., 2003). Resistance has been slowed in pest populations through high doses of Bt toxin expressed in plant tissues. This decreases the likelihood of survivorship, ensuring that insects are not exposed to sublethal doses that might promote development of resistance. This high dose strategy has been combined with the use of refugia which serve to maintain susceptible insect populations that delay resistance (Roush, 1994; Tabashnik, 1994).

5.3.4.1  Impact
In 347 Chinese rice fields farmers growing non-transgenic rice, small and poor farm households benefited from 6-9% higher transgenic rice yields and reduced pesticide use by 80% (Huang et al., 2005). The negative impacts of insecti­cide use on the environment and on the control of pests by beneficial insects have been extensively documented (Way and Heong, 1994; Pingali and Roger, 1995). Recent reports on several farming systems incorporating these insect resis­tant (IR) crops confirm increases in beneficial insects and a return of songbirds (FAO, 2004; Morse et al., 2004). IR crop growers are likely to also see savings in fuel consump­tion and decreased greenhouse gas emissions (Phipps and Park, 2002).
     Micronutrient-enriched crops can do much to improve human health in the region. While the consumption of green-leafy vegetables and unpolished or brown rice can mitigate the effects of vitamin A deficiency which is com­mon throughout the ESAP region and causes over 1 million deaths and partial or complete blindness in 0.25-0.5 million of the poorest children each year (Conway and Toennissen, 1999; Hunter, 2000), these are not always consumed in the region for a variety of reasons including lack of irrigation, poverty and lack of knowledge (Mishra, 1996; Pee et al., 1998; Khadka, 2001; Faruk et al., 2003). Rice, chosen be­cause it is a staple in the ESAP region and engineered to overproduce pro-vitamin A or beta-carotene can greatly reduce Vitamin A deficiency (Ye et al., 2000). Rice is also being targeted to address iron deficiency, identified as a contributing factor in over 20% of post-partum maternal deaths in Asia and Africa (Conway, 1999; Goto et al., 1999; Lucca, 1999). Transgenic crops can potentially have direct positive effects on health and nutrition through the elimi­nation of toxins, e.g., cassava (Siritunga et al., 2003) and increases in nutrients or antioxidants (Regierer et al., 2002; Bovy et al., 2002).

5.3.4.2   Challenges
Transgenic technologies can increase crop yields and lower pesticide use, but can also threaten livelihoods and cropping systems if biodiversity is reduced and farmers do not profit after committing scarce resources to these expensive agricul­tural packages. In many ESAP countries where seed saving is common practice, farmers can save traditional seeds and other public varieties, but would have to expend resources in the purchase of transgenic seed. While economic loss from the inability to save seed may be recouped by gains from in­creased yield and reduced input costs, transgenic crops have

the potential to confer an economic advantage only in the presence of the stress they are engineered against. If the risk and debts incurred by growers of transgenic crops are to be minimized, access to low-interest loans needs to be greatly improved and market and infrastructure instabilities effec­tively minimized.
     Most regulatory frameworks dictate that transgenic crops not be grown in areas where wild relatives are en­demic and often advocate a high dose strategy and the use of refugia. These precautions are considered to limit gene flow and delay resistance development in target insect popu­lations and will need to be enforced. This is likely to be a challenge in many ESAP countries that do not have strong regulatory and monitoring infrastructures. Thus, the risk of out-crossing is likely to be increased in these countries. A case in point is the "stealth seeds" phenomenon in India, which involved farmers multiplying, crossing and selling Bt cotton seed which was viewed as desirable but expensive to legally obtain. Although conventional breeding has already led to significant reductions in biodiversity via the replace­ment of land races with hybrids, such a result is of at least equal concern for transgenic crops. ESAP countries urgently need to invest in and enforce stringent biosafety protocols to assess the risk of gene flow and mitigate the cultural and biodiversity implications of "genetic pollution"  and the potential ecological consequences accompanying the cre­ation of "superweeds". To be effective, these protocols will need to include local agronomic, socioeconomic and ethical considerations.

5.3.5     Nanotechnology
Nanotechnology is defined as the "the design, characteriza­tion, production and application of structures, devices and systems by controlling shape and size at nanometer scale." (UK Royal Society and Royal Academy of Engineering, 2004). There are growing concerns regarding the safety and the long-term impacts of nanotechnology on food and agri­culture and its long-term prospects in large-scale replication and production of biological material such as proteins. The specific genetic modification of life-forms through nano­technology to give enhanced properties is also a subject of heated debate (ETC Group, 2004; UK Royal Society and Royal Academy of Engineering, 2004). International civil society groups monitoring developments in nanotech proj­ect that the impacts of nanobiotechnology in food and agri­culture will surpass that of the Green Revolution and farm mechanization in a couple of decades.
     The agricultural application of nanotechnologies is pri­marily focused on the seed and pesticide industries. In the area of seed development, researchers are experimenting on techniques that use nanoparticles to manipulate native DNA or insert foreign DNA into plant cells without being passed on the next generations, thus avoiding cross-polli­nation concerns (Dalke, 2003). Thai researchers at Chiang Mai University drilled a hole through the membrane of a rice cell to insert a nitrogen atom that would stimulate a rearrangement of DNA, resulting in grain color change and potentially other characteristics such as maturity period (Ranjana, 2004). The world's major agrochemical com­panies have already started commercially marketing pesti­cides formulated at the nanoscale, which are claimed to be