Fertilization of rootstocks of rubber tree in nursery suspended

Abstract

The production of rootstocks in nurseries rubber tree suspended prevents contamination by soil pathogens, however, little information exists about system this fertilization. This study aimed to determine the dosage of nitrogen, phosphorus and potassium in nutrient solution, over growth rubber tree rootstocks. The following concentrations were adopted: 0, 35, 70, 105 and 140 mg plant^-1 week^-1. The experimental design was randomized blocks, with 4 repetitions. Fertilizers were applied since October 2012 into January 2013. The plot consisted of 10 rootstocks rubber (unknown clone), sustained in the nursery suspended for PET. At 30, 45, 60, 75 and 90 days after application, were evaluated: stalk diameter, plants height, number of leaflets and color index. At 100th day, the final evaluation was carried out measuring the dry weight, foliar area and physiological indices. The dose of 140 mg plant^-1 fertigation is the most appropriate for the production of rootstocks nursery suspended. However, the full potential of plant growth was not achieved with the doses tested. To obtain satisfactory results is recommended to use high quality rubber rootstock seeds.