Crescimento e desenvolvimento de arroz (Oryza sativa L.) em solo salino-sódico submetido a diversos tratamentos de recuperação.

Abstract

In order to study the effects of the application of saline water in small volume and its successive dilutions in the recovery of a saline - sodium soils from the Irrigated Perimeter of Sumé (Sumé - PB), and its effects on rice culture (Ofiyza ÁatZva L .), an experiment was conducted under greenhouse conditions, with pots containing 6 kg of soil. A completely randomized design was used in a 4x4 factorial arrangement with 3 replicates, in which 4 treatments with water were studied: T1 - sanitation water, T2, T3 and T4 saline water in 2, 4 and 6 dilutions respectively; (20 t / ha), C3 - gypsum (10 t / ha) plus corral manure (20 t / ha) and C4 - - control (without gypsum without manure). Daily washes were carried out, the first one with 2500 ml of water and the others with 900 ml, recording the applied and percolated volumes. For daily washes with salt water in successive dilutions, the same concentration levels were applied only for two consecutive days. After the process was completed, washes were done with sanitation water for 4 consecutive days. After the washes, it was planted in the seedlings of rice of the cultivar BR IRGA - 409, for later evaluation of the following parameters: plant height, number of tillers and panicles per plant, shoot weight, yield and average grain weight. The use of saline waters markedly favored soil permeability, which was influenced by this parameter, when associated with the incorporation of gypsum. Corrective and saline water treatments did not show significant effects on average plant height at harvest, although the latter had a significant influence on the number of tillers and panicles per plant, with treatments T1 and T3 having the highest and lowest mean , respectively. For the production of paddy rice, the use of gypsum and saline water treatments showed significant effects, and the highest average was obtained with sanitation water treatment. The percentage of exchangeable sodium in the soil after the experiment and the yield of rice obtained showed a significant correlation (r = - 0.8 2). Rice acculturation and the treatments studied did not influence soil pH, but there was a reduction in the electrical conductivity of the saturation extract and the percentage of exchangeable sodium, and for the latter parameter the effects were significant for saline water treatments, especially when in the presence of plaster.