The Contribution of Varietal Tolerance for Problem Soils to Yield Stability in Rice

摘要

The erratic performance of modern rice varieties in many countries has been attributed to physical and biological environmental stresses to which the plants are not adapted. This paper compares the field performance of different rice varieties in soils with common mineral stresses--phosphorus deficiency, zinc deficiency, or iron toxicity in wetland rice fields and iron deficiency in dryland rice fields. Genotypes of comparable high yield potential but different tolerance to mineral stresses were selected on the basis of greenhouse tests and tested for field performance (growth, yield, and mineral absorption) in mineral-stressed soils during the 1978 dry and wet seasons and the 1979 dry season in the Philippines.