Growth and yield of guava irrigated with saline water and addition of farmyard manure

Abstract

The guava production in northeast of Brazil has rapidly increased and moderately saline waters are commonly used in its irrigation. Considering that the use of marginal waters may be harmful to saltsensitive crops, an experiment was carried out in a greenhouse to evaluate the effects of electrical conductivity of the irrigation water (ECw – 0, 2, 4, 6 and 8 dS m-1) and addition of farmyard manure (0 and 3 kg 100kg^-1 of substrate) in development and yield of guava, cv. ‘Paluma’. Irrigation waters were prepared with 70% of NaCl and 30% of CaCl₂ on equivalent basis, and plants were irrigated three times a week and leaching was applied every 30 days to avoid excessive accumulation of salts in soil. Plants were cultivated in plastic containers of 15 cm diameter and 40 cm height with 13 kg of substrate and were harvested at 200 days after transplanting. Plant height, dry matter of all plant parts, leaf area, root/shoot ratio and water consumed were reduced by increase in ECw, while the presence of organic matter allowed higher values for most variables. Toxicity symptoms were observed even for the lowest saline water treatment (2 dS m^-1), and dry matter was more partitioned to leaves than to root in saline
conditions, contrary to observed in treatment irrigated with distilled water.