Abstract
Four different media: matrix culture, sa~d culture: hydroponic culture (N?-~ubbling) and h~~roponic culture (surface sealing) .were used to study the effect of hYPOXiaand salinity on two wheat vaneties (Pb.-85, salinity and waterlogging tolerant; 7- Cerros. salinity and waterlogging sensitive), In matrix and sand culture, hypoxia was induced by water standing continuously ,;Hup to the surface of pot, whereas in case of hydroponic culture, hypoxia was induced by: (a) continuous bubbling of N 2 gas .lr into the solution (b) surface sealing through effective covering of solution with foam sheet by sealing it from all sides using . packing tape. Sprouted seeds of wheat varieties were transplanted to fibre glass pots in the case of matrix and sand culture. while in hydroponic culture 10-day old seedlings ofthe varieties, raised in silica gravel, were transplanted to foam plugged holes in polystyrene sheet suspended over 25 litres of half strength Hoagland nutrient solution contained in plastic tanks. In matrix and sand culture, salinity stress was imposed at two leaf stage, whereas in hydroponic culture salt was added three days after transplanting of seedlings. Total salinity (* 100 mol m" NaCI + 10 mol m" CaCI2 ) was developed in tour equal increments in all the media. After 8 weeks of growth period harvesting was carried out. Results revealed that all the techniques used to create hypoxic environment were positively correlated with each other, Although there was a positive correlation among techniques, growth data (shoot and root fresh weight) showed more pronounced adverse effects of hypoxia only in the case of matrix culture indicating that matrix culture is the appropriate medium for such studies
