Produção de porta-enxerto de goiabeira crioula irrigado com águas salinizadas e doses de nitrogênio.

Abstract

The culture of guava has Increasingly demonstrating your agricultural importance arousing the interest of small, medium and large producers both paragraph export as domestic consumption. As arid and semiarid have a low availability of good quality para Irrigation water, where, many times, Becomes Necessary the use of saline waters, is usinag such in May Technical Development Dependency become possible employment of these Pará Water Production agricultural. With the objective is to isto é with this work to evaluate the effects of using different nitrogen levels combined with Distinguished Saline Water levels in seedlings grown paragraph rootstock of guava. The experiment was developed in greenhouse (protected environment) Science and Technology Center of Agrifood Federal University of Campina Grande (CCTA / UFCG), located any municipality of Pombal-PB. The experimental design was randomized blocks in a factorial scheme 5 x 4 with OS Treatments related to the five levels of electrical conductivity of irrigation water (CEA) 0.3; 1.1; 1.9; 2.7 and 3.5 dS m-1 in interaction with four nitrogen (N): 70, 100, 130 and 160% of the Recommended N dose paragraph guava plants. Four replications were used, with two plants per experimental unit for assessment cv. Crioula. It began treatment application from 25 days after seedling emergence (DAE). The stem diameter variables were assessed, number of leaves and leaf area to 190 DAE, and physiological related to the absolute growth rate and relative plant height and stem diameter in periods of 25-190 DAE. The variables of fresh weight and dry stem, leaves and shoots, dry matter of root, total dry and the Dickson quality index were evaluated at 190 DAE. The greatest growth and quality to the rootstock of guava 'Creole' is obtained with electrical conductivity of water 0.3 dSm-1 and fertilization with 541.1 mg of N dm-3 of soil. increasing doses of N did not reduce the deleterious effect of irrigation water salinity on the growth of rootstocks of guava 'Creole'. CEA irrigation water up to 1.75 dS m-1 in the production of guava rootstock promotes acceptable reduction in growth and quality of plants 10%. The dose of 70% of N (541.1 mg N dm-3 of soil) stimulates growth, dry matter accumulation in the shoot and the quality of guava cv rootstock. Creole. Nitrogen fertilization at doses of 70 and 100% of N reduces the effect of irrigation water salinity on the relative growth rate of the diameter of guava rootstocks stem. The increase in nitrogen fertilization did not reduce the effects of salinity on the variables studied.