Table 2.

Environmental risks and likelihood of risks on the use of candidate abiotic stress tolerance genes in transgenic plants.

Transgene/protein	Potential hazard/risk	Likelihood of risks
codA (encoded protein/Glycine betaine)	Confers selective advantage, fitness, better plant growth may increase competitive potential of crop plants Allelopathic effect on surrounding plant vegetation and soil microbe diversity and functions Changes in salt tolerance may affect structure and functions of soil microbes	Selective advantage is limited, only under stress condition No competitiveness, weediness in crop plants No known adverse/allelopathic effects Metabolic changes, allelochemicals may have effects Unknown effects on rhizosphere microbes through changed salt tolerance, water and nutrients
DREBs/transcription factor proteins	Confers selective advantage under stress condition May have cross tolerance May have unintended effects These all factors may increase plant fitness	DREBs have no direct effects on plant diversity Selective advantage is limited and only under stress condition Cross tolerance may involve physiological, metabolic burdens, reduced fitness Increased fitness or differences in fitness and weediness traits, may not affect biodiversity May affect microbe diversity through changed soil abiotic condition
Na+/H+ antiporters	May confer selective advantage, improved phenotype Increased fitness may increase persistence and competitive ability of crop plants Selective advantage and improved phenotype may affect rhizosphere microbes and their functions	These genes and the encoded proteins are native to plants Selective advantage is limited that may not change persistence and volunteer potential Changed salt tolerance may have effects on soil microbes through changed water and nutrients