Desenvolvimento de mudas de goiabeira irrigadas com água salina.

Abstract

The production of guava for the commercialization natura' is growing and constitutes an important economic activity in the Brasilian Northeast with the help of irrigation. Use of saline waters in irrigation is common in this region. Considering that the irrigation under these conditions may affect the plants, this study was conducted in a completely randomized design in a greenhouse, adopting a factorial (5 x 2) scheme. The effect of five levels of salinity of irrigation water (0,0,2,0,4,0,6,0 and 8,0 dS m"1 at 25° C) were tested using a soil with and without organic matter on the development of guava plants, obtained from cuttings of the cv. 'Paluma'. In the preparation of irrigation waters, 7:3 equivalent proportion was used, respectively for Na:Ca. The growth and development of plants were appraised up to 200 days after the transplanting. According to results obtained, the 'Paluma' is sensitive to the salinity o f irrigation water; the growth and development of the plants, in terms of height and leaf area were more affected above 2,0 dS m"1 and in higher levels plants died. The use of waters of electrical conductivy starting from 2,0 dS mf1 reduced the phytomass of leaves, stem and fruits drastically; the organic matter favored the growth and development of the guava plant; the root system was more affected by the salinity than the aerial part; the increase in water salinity decreased the evapotranspiration of the plants. In the leaves, toxicity symptoms of the salts appeared and were registered through photographs.