Crescimento, fisiologia e rendimento de genótipos de mamoneira sob lâminas de irrigação.

Abstract

The castor bean (Ricinus comiunis L.) is an oilseed crop of outstanding importante in Brazil and the world. since it can be used in different áreas of industry, and it is also very resistant to drought, and an alternative for planting in áreas of the Brazilian semi-arid however, it is of great importante to identify materiais with greater economic potential and requiring lower water demand. The objective was offhis work to analyze the growth, gas exchange and the yield of six castor bean genotypes under different irrigation leveis. The field experiment was conducted in Sousa, PB, with drip irrigation system. The treatment compreses four rrigation leved (25,50,75 and 100) as six castor bean genotipes BRS-ENERGY, Gen CNPAM 2001-42, Gen CNPAM 2001-49, Gen CNPAM 2001-5, Gen CNPAM 2001-50, Gen CNPAM 2009-7. The was analyses growth variables, gas exchange and feed. The data were subjected to analysis of variance with the 'F' test, following regression analysis for irrigation levei in each genotype evaluated. The irrigation leveis corresponding to 50% and 75% ETc are the most recommended for the growth of castor bean in the semiarid region of Paraíba, regardless of genotype. Among the genotypes the BRS Energy the most recommended for growth in semiarid region, being abre to use the estimated 64% of ETc. The CNPAM 2009-7 showed the lowest yield between the genotypes evaluated. The CNPAM 2001-49 is the genotype showed greater tolerance to water stress and is recommended to compose breeding programs.