Crescimento de porta-enxerto de goiabeira sob águas salinizadas e doses de nitrogênio.

Salt stress suffered by plants due to concentration of irrigation water salts reduces the ability of exploitation of cultures especially in arid and semiarid regions. Thus, the aim of this study was to evaluate the effect of salinity of irrigation water on the growth of rootstock of guava 'Crioula' associated with increasing doses of nitrogen fertilizer. The experiment was conducted in plastic pots under greenhouse conditions in the CCTA / UFCG. We used the experimental randomized block design, with the treatments in a factorial 5 × 4, corresponding to five levels of electrical conductivity of the water - CEa (0.3; 1.1; 1.9; 2.7 and 3.5 dS m-1) and four nitrogen rates (70, 100, 130 and 160% of the recommended dose N for guava cultivation seedlings cv. Paluma) with 4 replications and 5 plants per plot. The dose of 70 % of N- ( 541.1 mg N dm-1 of soil ) provides greater production plant leaf area, height 145 DAE, but to stem diameter was significant in both periods studied the rootstock guava cv. Crioula. Irrigation CEa above 0.3 dS m-1 negatively affect the number of leaves, leaf area, stem diameter, leaf area ratio and absolute growth rate of stem diameter. There was interaction between the factors salinity of irrigation water and nitrogen fertilization for variable number of leaves at 145 DAE rootstock of guava "Crioula". [ABSTRACT FROM AUTHOR]