Abstract
A drip irrigation experiment was established 17 December 1983 at Fortuna Substation, Juana Díaz, P. R., to evaluate effects of various fertigation rates (T1 = 13.8, T2 = 8.3 and T3 = 4.1 g of N per plant in 10 weekly applications), fertilization (T4 = 6.9 g of N per plant on day 6 and 56); and no fertilization on root distribution at 0-11, 11-22, 22-33 and 33-44 soil depth. Effect of silver coated plastic mulch was also evaluated. Fresh root weight and percent distribution values at four depths were not statistically different at P=0.05 among all treatments. In all fertigation treatments under mulching, the root values were significantly higher at P = 0.05 for 00-11 cm soil depth than values for other soil depths. More than 80% of the roots were within 00-22 cm soil depth in all plots; this depth corresponds to wetting zone under a dripper.