Crescimento e componentes de produção de girassol com água salinizada e adubação nitrogenada.

Abstract

The sunflower ( Helianthus annuus L. ) has enormous potential as oilseed plant and currently , the major motivation for the production of sunflower oil is the production of biodiesel in Brazil . The study was conducted in order to evaluate the growth variables of EMBRAPA 122- V2000 Sunflower in the period April-July 2012 , submitted to irrigation with increasing water salinity and nitrogen fertilization . The research was conducted in the greenhouse of the Federal University of Campina Grande , in a completely randomized design using the 5 x 5 factorial, related to salinity levels of irrigation water expressed by electrical conductivity : 0.7 , 1.7, 2 , 7 , 3.7 and 4.7 dS m - 1 (25 ° C ) and nitrogen levels : 50, 75 , 100, 125 and 150 ppm , in three replicates , totaling 75 experimental units . The variables assessed during the crop cycle were : plant height , stem diameter , number of leaves , leaf area , beginning of bloom , full flower opening and chlorophyll content . We observed that the variables evaluated were affected significantly with the electrical conductivity of 0.7 dS m - 1 in a linear and decreasing manner. On the other hand, it appears that these variables , except for plant height at 15 DAS which took a significant effect in the interaction , have not changed between the salinity interaction of water versus nitrogen fertilization. The initial and full phases of flowers were delayed by the increase in the salinity of irrigation water and chlorophyll content decreased by increasing the levels of salinity irrigation .