Genetic analysis of agricultural traits in rice related to phosphorus efficiency.

Relative tillering ability, available spike, biomass, and grain yield of P1, P2, F1, and F(2,3) were used to study the genetic development of rice related to phosphorus efficiency with a quantitative genetic model. The results indicated that under a low-P condition, the relative tillering ability and the relative available spike were apt to the additivity-dominance-epistasis model with two couples of major genes, between which additive, dominant and epistatic effects existed, and with multi-gene modifications. Their maximum major gene effect mostly indicated additivity, but sub-maximum major gene effect mostly indicated dominance.