true that in certain cases, pesticides have reduced the effect on nontarget organisms, biodiversity, evolution of resistance and genetic contamination are some of the concerns.
     In Bt crops, if insects developed resistance to the en­gineered Bt toxin, conventional farmers would revert to chemical insecticides, while organic farmers would have lost one of their most valuable pest control agents. In ad­dition superbugs could emerge—insects that have adapted their behavior and genetics in unpredictable ways to survive in the constant presence of toxins (Stone, 2002). In certain cases, effects on nontarget organisms have been observed (Hilbeck et al., 1998).
     Some studies indicate the presence of transformation-induced mutation in commercial crops poses a potentially large biosafety risk (Wilson et al., 2006). This has led to a call for a transparent manner for testing for each individual product before market introduction (Pryme and Lembcke, 2003).
     The difference in approach is wide between farmers acting on their traditional knowledge and the new biotech-nologists. The first take a broad and holistic approach to a specific agronomic and socioeconomic situation; the latter tend to look for universal, deep-down, molecular solutions. They offer widely differing solutions for problems dealing with pests, diseases, weeds, water, plant nutrients, soil deg­radation and yield (Table 2-9).
     Genetic modification for disease or pest resistance can­not solve the problem of disease or pest attack because in­tensive agriculture created the conditions for new pathogens (Ho, 1998). For example, a variety of rice hybrid, IR-36, created to be resistant to eight major diseases and pests in­cluding bacterial blight and tungro, was attacked by two new viruses, ragged stunt and wilted stunt.

2.4.1.4 Agricultural sustainability
The idea of agricultural sustainability centers on the need to develop technology and practices that do not have ad-

verse effects on the environment and human health and at the same time lead to improvement in food and productiv­ity. Sustainable agriculture approaches come under many names: agroecology, organic farming, low external input farming, ecological agriculture, biodynamic agriculture and permaculture (Ho and Ching, 2003). Sustainability in agri­culture has been defined as having two dimensions: natural resource sustainability and socioeconomic sustainability.
     Sustainable agriculture requires site-specific technology. For example, organic farms vary in complexity and diver­sity. Studies show that a particular technology can be suc­cessful in one site but not in another (Niggli and Ogorzalek, 2007). Evidence from many grassroots development proj­ects also has shown that increasing agricultural productivity with agroecological practices, including organic agriculture, increases not only food supplies but also incomes, thus re­ducing poverty, increasing access to food, reducing malnu­trition and improving livelihoods of the poor.
     The question that arises is whether sustainable agricul­tural practices such as organic farming can be the solution for the future. The debate on the merits and disadvantages of organic versus conventional agriculture continues to in­fluence decision makers. The benefits of organic agriculture are several:
•   There is a thriving demand for organically grown food in urban centers of many Asian countries. The premi­ums paid for organic food offer an opportunity for poor farmers to increase their income (IFAD, 2002). Organic agriculture has the potential to improve house­hold food security and meet the goals of poverty allevia­tion and environmental sustainability in ESAP (ESCAP, 2002).
•   There may be employment effects: Some organic sys­tems may require more labor, which can be negative or positive. The crop diversification that generally happens on organic farms distributes labor throughout the sea­son. This can contribute to stabilizing employment, re-