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The aim of this research was to characterize the biochemical behavior of sorghum plants under saline stress using multivariate statistical analysis methods for efficient management of Sorghum bicolor [Moench.]). The experimental design was completely randomized design composed of three saline concentrations (0, 1.5 and 2.0 M) in 10 replications. In the multivariate analysis (hierarchical method), there were distinct and sub-groups in the sorghum plant treatments. Group 1 consisted of the root parts and under this group there were two subgroups: 1.5 to 2.0 concentration (Group 1) and 2 concentration (Group 2). The increase of NaCl concentration in the roots and leaves has inverse correlation with decrease of nitrate reductase, amino acids, protein and starch. The amounts of amino acids, carbohydrates, sucrose and proline in the roots and carbohydrates, sucrose and proline in the leaves of sorghum plants are reliable biological indicators of saline stress conditions in the soil. The nitrate compound differed (p ≤ 0.05) in the sorghum plant roots; it had an average value of 0.04 μmol kg-1 of nitrate in the control treatment dry matter. The nitrate average was between 0.04 and 0.06 μmol kg-1, but without statistical difference for all concentrations.Key words: Multivariate statistics, salt concentration, proline, carbohydrate.

Made available in DSpace on 2022-04-28T19:02:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01 The crabwood has high phenotypic plasticity due to its adaptability to different environments. The aim of this work was to evaluate the content of nitrate, free ammonium, nitrate reductase activity (Nra), and the levels of total soluble amino acids, proline, glycine betaine in young plants of crabwood (Carapa guianensis Aubl.) under to three water regimes and subsequent recovery process through the stresses suspension. The experiment was carried out on a greenhouse from Universidade Federal Rural da Amazônia, Capitão Poço city, PA State. A completely randomized design on factorial scheme 3×5 was used (three water conditions: irrigated control, water deficit and flooding; and five evaluation times: 0 day, 10 days, 20 days, 30 days and suspension of water stress after 72 hours from the 30th day) with five repetitions, totalizing 75 experimental units. The results showed that the water potential, nitrate concentration and the Nra decreased significantly in plants under water stress, as well as in plants under flooding, with average of -3.46 MPa, 0.6 NO3-/kg DM, 0.1294 μmoles of NO2-/g FM/h (water potential, nitrate and Nra, respectively). The ammonium (NH4+) levels increased in the plant under water stress. The increasing level was more significant in the plants under water deficit, averaging 4.0 of mmol of NH4+/kg of DM. The amino acids levels, proline and glycine betaine had a significant increase in plants with water stress, especially in the plants under water deficit. The plants subjected to flooding did not show any significant result. After the suspension of the water stress, only the contents of free ammonium and levels and total soluble amino acids recovered to their initial values. To others variables, the stress suspension period was not enough for plant's total recovering. The young plants of crabwood subjected to water stress promoted changes in nitrogen metabolic pathways. These changes showed a bigger tolerance of the plants of crabwood to flooding. Engenheira Florestal estudante de Doutorado em Ciências Florestais UFRA- Universidade Federal Rural da Amazônia Engenheiro Florestal estudante de Mestrado em Ciências Florestais UFRA- Universidade Federal Rural da Amazônia Engenheiro Agrônomo estudante de Doutorado em Ciências Florestais UFRA- Universidade Federal Rural da Amazônia Estudante de Agronomia UFRA- Universidade Federal Rural da Amazônia Engenheira Agrônoma estudante de Mestrado em Ciências Florestais UFRA- Universidade Federal Rural da Amazônia Engenheira Agrônoma estudante de Doutorado em Agronomia (Ciência do Solo) Universidade Estadual Paulista Júlio de Mesquita Filho Biólogo Professor Doutor do Instituto de Ciências Agrárias UFRA- Universidade Federal Rural da Amazônia Engenheiro Agrônomo Professor Doutor do Instituto de Ciências Agrárias UFRA- Universidade Federal Rural da Amazônia Engenheira Agrônoma estudante de Doutorado em Agronomia (Ciência do Solo) Universidade Estadual Paulista Júlio de Mesquita Filho

A maioria dos solos agricultáveis da Amazônia tem alta acidez, capacidade de troca catiônica e fertilidade considerada baixa. Os solos de Terra Preta de Índio possuem altos teores de Ca, Mg, P, Zn, Mn, Cu e C orgânico. O objetivo deste trabalho é avaliar os teores de macronutrientes encontrados nas Terras Pretas de Índio e compara-los aos encontrado no solo adjacente. As coletas de solo foram realizadas no Sitio Arqueológico Jabuti. O solo pertence à Ordem dos Gleissolos. As coletas foram realizadas em três áreas do sitio E1S1, E1S2 e área adjacente a 5-10 cm de profundidade. Os valores médios de Ca+2 foram maiores nos solos de Terra Preta de Índio quando comparado com o solo adjacente. Enquanto os valores médios de Mg+2 foram de 4.20; 2.40 e 1.55 cmolc/dm3 E1S1, adjacente e E2S1 respectivamente. Os valores de P disponível na terra preta de índio foram superiores. Os valores médios de K+ nos solos estudados foram de 0.24; 0.18 e 0.17 cmolc/dm3 na adjacente, E1S1 e E2S1 respectivamente. Os maiores teores de carbono foram encontrados no ponto de coleta E2S1 e E1S1 do sítio de Terra Preta de Indio, com valor máximo de 59.45 g kg1 (E2S1) e 55.51 g kg1 (E1S1), sendo o valor mínimo encontrado na área adjacente ao sítio (37.57 g kg1).