Germination and initial growth of two cultivars of castor bean under saline stress

Abstract

Two castor bean cultivars (Ricinus communis L.), BRS-188 Paraguaçu (C₁) and CSRN-367 (C₂), were irrigated with five waters of different electrical conductivity levels (0.7, 2.7, 4.7, 6.7 and 8.7 dS m^-1) in a radomized design with 3 replications and 5 x 2 factorial treatments distributions. Germination percentage, time and emergence speed index, plant height stem diameter, number of leaves and leaf area at 20, 40 and 60 days after planting were evaluated. Number of leaves and leaf area was higher in the cultivar C₁ and a higher germination percentage and faster emergence were observed in the cultivar C₂. Increasing salinity reduced germination percentage, made the emergence slower and diminished all the growth characteristics analyzed.

Key words:
Ricinus communis; BRS-188 Paraguaçu e CSRN-367 cultivars; tolerance.