DISTRIBUCIÓN DE BIOMASA Y ACUMULACIÓN DE PLOMO EN CALABACITA (Cucurbita pepo L.) CULTIVADA EN SUELO CONTAMINADO

Abstract

The effect of lead-contaminated soil in hybrid squash “Termo” (<em>Cucurbita pepo</em> L.) was studied. The hybrid was grown in blackpolyethylene bags in the field. The variables evaluated were distribution of biomass production, plant height, chlorophyll content and lead accu¬mulation in root, stem, leaf, flowers and fruits. The treatments were 0, 65, 300 and 1000 ppm lead applied to soil through Pb(NO3)2. The randomized complete blockdesign with six replicates was used, and the experimental unit was a blackpolyethylene bag with two plants. Plant height and chlorophyll content evaluations were performed 50 days after transplantation, and fresh weight, dry weight and lead accumulation 52 days after transplantation. It was observed that plant height was significantly lower when lead was applied at any dose. The highest biomass accumulation in root and stem was produced with 300 ppm and in fruit with 65 ppm lead, while total biomass and SPAD units (chlorophyll) were not affected. In the case of edible structures, flowers had higher metal accumulation than fruits. Flowers showed the highest lead accumulation when lead doses were low. This suggests that it is appropriate to assess the content of heavy metals in agricultural products for human consumption, even when they come, supposedly, from uncontaminated soils.