The effect of irrigation on the growth of rubber tree under nursery conditions

Abstract

An experiment aiming to evaluate the effects of irrigation and the irrigation x fertilizer interaction on rubber tree (Hevea spp) height and stem diameter was conducted under nursery conditions in a yellow latosol of the Rubber and Oil Palm Research Center/EMBRAPA, in Manaus, AM, Brazil. The experimental design was in randomized blocks, in factorial arrangement, including the following treatments: irrigated-fertilized (IF); irrigated-nonfertilized (INF); nonirrigated-fertilized (NIF); and, nonirrigated-nonfertilized (NINF). Irrigated treatment plots were watered up to field capacity to the depth of 25 cm whenever the soil matric potencial (Ψ m) reached -0.5 bar, while in the fertilized plots five NPKMg (12-10-17-3) applications were made every 30 days starting 60 days after planting. During the first two years, irrigated treatments showed better results than nonirrigated ones, particularly when irrigation was associated to fertilization. The results of the several treatments showed a decreasing sequence: IF> INF > NIF> NINF.