Crescimento e nutrição de clones de Hevea brasiliensis sob diferentes doses de nitrogênio, fósforo e potássio

Abstract

The assessment of nutritional status of plants such as rubber is important, as it needs, at all stages of its development of a proper fertilization program, which combined with the correct choice of genetic material, will generate significant productivity gains by avoiding the use unnecessary nutrients. There is a growing demand for natural rubber in the world, and the state of Rio de Janeiro land with favorable conditions for the development of the culture of rubber. Combined with social, economic and environmental importance, rubber cultivation is an alternative economic value to degraded areas and rugged state. The hypothesis is that the adaptation of rubber tree clones is related to genetic material and nutritional demand, reflecting productivity. The objectives of this study were to evaluate the growth of the clones RRIM 600 and PR 255 of Hevea brasiliensis in relation to different levels of nitrogen, potassium and phosphorus. They were tested 28 combinations of nitrogen, phosphorus and potassium for each of the clones, and data were collected from height, diameter and dry weight of plants. Crossing the information, the best results overall were obtained with the treatments 2 (40-50-40), 5 (40-100-40) grams of nitrogen, phosphorus and potassium per plant respectively. Both clones use on average, the same amount of nutrients, but clone RRIM 600 develops more at first, indicating less efficient use of nutrients by clone PR 255, which should not be used on poor soils when compared to the RRIM 600