The correlation between biomass and drainage line was behaved by the effect of water on root growth. The result showed that a ratio of aeration part over the drainage line up to 0.6 kept more than 60 percent of roots being in a good aeration condition for a long duration, resulted in the increasing of the CTK and IAA concentration and decreasing of the GA and ABA concentration in roots, and promoted the emergence of new roots and branches. Regression analysis of biomass showed that there was a production peak when the drainage line was near to the golden section. The theory of The Golden Drain...
