Resumo O objetivo deste trabalho foi avaliar o desempenho agronômico de milho (Zea mays) solteiro e consorciado com Urochloa ruziziensis em sucessão à soja (Glycine max) inoculada com Bradyrhizobium japonicum, bem com a inoculação e a reinoculação do milho com Azospirillum brasilense, em dois solos contrastantes. O experimento foi realizado em duas safras, em delineamento de blocos ao acaso, em arranjo fatorial 2x2x3, com cinco repetições. O primeiro fator avaliado foi composto pelos dois solos contrastantes: Latossolo Vermelho eutrófico argiloso e Latossolo Vermelho distrófico arenoso. O segundo fator foi o cultivo de milho: solteiro e consorciado com U. ruziziensis. Já o terceiro fator consistiu na inoculação em soja e milho em sucessão, como a seguir: sem inoculação nos dois cultivos, inoculação com Bradyrhizobium japonicum em soja e com A. brasilense em milho, e reinoculação com B. japonicum + A. brasilense em soja e com A. brasilense em milho. Nos dois anos de cultivo, as maiores produtividades de milho são observadas no solo argiloso com sementes reinoculadas com A. brasilense. A reinoculação anual com A. brasilense resulta em maior produtividade de grãos de milho no consórcio com U. ruziziensis no solo argiloso. A inoculação e a reinoculação reduzem as perdas de produtividade do milho causadas pela competição com U. ruziziensis no consórcio.

Abstract The objective of this work was to evaluate the agronomic performance of corn (Zea mays) grown single and intercropped with Urochloa ruziziensis in succession to soybean (Glycine max) inoculated with Bradyrhizobium japonicum, as well as the inoculation and reinoculation of corn with Azospirillum brasilense, in two contrasting soils. The experiment was carried out in two crop years, in a randomized complete block design, in a 2x2x3 factorial arrangement, with five replicates. The first evalauted factor was composed of the two constrasting soils: a clayey Rhodic Eutrustox and a sandy Rhodic Haplustox. The second factor was corn cultivation: single and intercropped with U. ruziziensis. The third factor consisted of the inoculation onto soybean and corn in succession, as follows: no inoculation in both crops, inoculation with B. japonicum onto soybean and with A. brasilense onto corn, and reinoculation with B. japonicum + A. brasilense onto soybean and with A. brasilense onto corn. In both crop years, the highest corn yields are observed in clayey soil with seeds reinoculated with A. brasilense. The annual reinoculation with A. brasilense results in a higher corn grain yield in the intercropping with U. ruziziensis in the clayey soil. Inoculation and reinoculation reduce corn yield losses caused by the competition with U. ruziziensis in intercropping.

ABSTRACT Abiotic factors, such as saline stress, can happen in agricultural areas and can harm the metabolism of the plants. Studies that seek to evaluate the acting of P. peruviana L. under stress conditions are still incipient. Therefore, the objective was to evaluate the tolerance to salinity in plants of P. peruviana L. under different saline levels of irrigation water. The work was developed in the experimental farm of the Universidade Federal de Campina Grande, Campus Pombal, PB, from January to March 2017. Four saline concentrations of irrigation water were used (0.3; 1.2; 2.1; and 3.0 dS m-1) with five repetitions. At 60 days after the transplant, were evaluated the leaf area, intercellular CO2 concentration, stomatal conductance, transpiration, photosynthetic rate, intrinsic water use efficiency, instantaneous carboxylation efficiency, electrolyte extravasation, chlorophyll a, b and carotenoids. The results show that saline levels of irrigation water up to 3.0 dS m-1 did not provide physiological damages in plants of P. peruviana L. until 60 DAT, except for extravasation of electrolytes and chlorophyll a and b, characterizing the plant as tolerant to salinity until the studied level.

Abstract Moringa oleifera Lam., is a tree species that has several purposes of use, standing out in the recovery of degraded areas and the use of seeds as biodsorbents in water clarification. However, ony a little is known about the behavior of seed germination under saline conditions, common in soils and water in the Brazilian Northeast. Thus, the objective was to evaluate the increment of water during the soaking and seed germination of M. oleífera that were submitted to different electrical conductivity of the irrigation water. The work was developed following a completely randomized design, with stress simulation employing saline solutions at the concentrations of 0.0; 3.0; 6.0 and 9.0 dS m-1. To determine the soaking curve, the water increment of the soaked seeds in the different saline solutions was monitored at regular intervals with four replications per treatment. To characterize the physiological quality of the seeds, the percentage, first count, speed index, average time and average germination speed were evaluated. The M. oleífera is tolerant to the effect of salinity during the germination phase, however seed vigor is reduced as a function of increased salinity. Soaking the seeds makes begin the phase II of the germination process around 10 hours and extends for up to 50 hours, when phase III begins, they absorb approximately 0.2 g of water and require 86 hours for germination. Salinity reduces the absorption and increase of water in the seeds.