The peanut crop, owing to its microbiological and nutritional aspects, is of great economic importance for agriculture and the food industry. However, salt stress can negatively affect nutrient uptake and plant growth. The objective of this study was to evaluate the growth and foliar nutrient concentrations of peanut plants subjected to irrigation with saline water and different forms of organomineral fertilization. The experiment was conducted in a greenhouse in a completely randomized design (5 × 2 factorial scheme) with five forms of fertilization (F1 = 100% mineral; F2 = 100% bovine biofertilizer; F3 = 100% vegetal ash; F4 = 50% mineral + 50% bovine biofertilizer; and F5 = 50% mineral + 50% vegetal ash), two levels of electrical conductivity of the irrigation water (ECw) (1.0 and 5.0 dS m-1), and five replicates. Salt stress inhibited plant growth and the number of leaves, but increased the average stem diameter with the use of 100% bovine biofertilizer and higher salinity water. When ECw of 5.0 dS m-1 was used along with the bovine biofertilizer (100%), the P concentration in plants increased. The K concentration was reduced in plants fertilized with bovine biofertilizer (100%) and vegetal ash (100%), while Mg concertation was reduced in plants fertilized with bovine biofertilizer (100%) or mineral fertilizer (50%) + bovine biofertilizer (50%) with irrigation water of 5.0 dS m-1.

Irrigation with saline water affects the agronomic performance of the maize crop; however, the use of vegetal mulch may mitigate salt stress and promote an increase in yield. In this way, this study aimed to evaluate the grain yield of the maize plants submitted to different water salinity levels in the presence and absence of mulch. The experiment was conducted in a randomized block design arranged in a 2 × 2 factorial scheme. The first factor was the salinity of the irrigation water (1.0 and 4.0 dS m-1) and the second, with and without mulch, and five replicates. The variables analyzed were: unhusked ear mass, husked ear mass, cob mass, straw mass, husked ear diameter, husked ear length, and yield. The irrigation water with higher electrical conductivity affects negatively the ear mass with and without straw, ear diameter and ear length. The use of vegetation cover on the soil increased the unhusked ear mass with and without straw, ear diameter and length. The water with higher salinity (4.0 dS m-1) reduces the maize grain yield but with less intensity in the presence of mulch.

The objective of this study was to evaluate the production of watermelon seedlings irrigated with saline waters and cultivated in different types of environments and substrates. The experimental design was completely randomized with split-split plots, in which the plot corresponded to two growing environments (EN1 = full sun and EN2 = 50% shade black net), the subplot to two types of irrigation water (IW1 = 0.8 and IW2 = 2.5 dS m-1) and the sub-subplot to four types of substrates (SB1 = vermiculite + coconut fiber, SB2 = manure + soil, SB3 = carbonized rice husk + soil, SB4 = biochar + soil), with four replicates of twenty-five seeds. The variables analyzed were: emergence percentage (EP), emergence speed index (ESI), mean time of emergence (MTE), number of leaves (NL), stem diameter (SD), seedling height (SH) and root length (RL), shoot dry mass (SDM), root dry mass (RDM) and total dry mass (TDM). The EN2 treatment provided better conditions for emergence and initial growth, and EN1 was also favorable to the emergence and initial growth of watermelon seedlings, when the substrates SB1 and SB2 were used.

The excess of salts may compromise the growth and physiological functions of plants, but the use of bovine organic fertilizer can mitigate these effects. It was intended was to evaluate the saline stress in soil with and without bovine organic fertilizer on the initial growth, the accumulation of biomass and the gas exchanges of the okra culture. The test was conducted at the UNILAB’s experimental farm, in Piroás, in Redenção – CE city. The treatments were distributed in a completely randomized design with five replications, in a 5 x 2 factorial concerning five irrigation water salinity levels (1.0; 2.0; 3.0; 4.0 and 5.0 dS m-1), in the presence and absence of bovine organic fertilizer. Plant height, stem diameter, root length, a dry mass of shoot, photosynthesis, transpiration and stomatal conductance were evaluated. The bovine organic fertilizer promoted better means in initial growth and biomass in okra plants compared to the control treatment, thus showing efficiency in the attenuation of the salts present in irrigation water. The increase in the saline concentration of the irrigation water reduced the gas exchange (photosynthesis, stomatal conductance and transpiration) in okra plants. Nonetheless, in smaller proportions in the soil with the bovine organic fertilizer.

The use of organo-mineral fertilizer is an alternative measure to mitigate salt stress in semiarid regions. Thus, the objective of this work was to evaluate the physiological indexes of peanut crops under irrigations with fresh and brackish waters and applications of organo-mineral fertilizers. The experiment was conducted from June to September, 2019, at the Universidade da Integração Internacional da Lusofonia Afro-Brasileira (UNILAB), in Redenção, state of Ceará, Brazil, using a completely randomized experimental design in a 5 × 2 factorial arrangement, with four replications. The treatments consisted of five soil fertilizers (F1= 100% NPK mineral fertilizer at the recommended rate; F2= 100% bovine manure-based biofertilizer; F3= 100% plant ash; F4= 50% mineral fertilizer and 50% bovine manure-based biofertilizer; and F5= 50% mineral fertilizer and 50% plant ash); and two salinity levels (electrical conductivities) of the irrigation water (1.0 and 5.0 dS m-1). Photosynthetic rate, transpiration, stomatal conductance, leaf temperature, internal CO2 concentration, water use efficiency, and chlorophyll index of the plants were evaluated at 40 and 54 days after sowing (DAS). Plants irrigated with fresh water presented higher stomatal conductance, photosynthetic rate, and transpiration, regardless of the fertilizer used. The use of 100% bovine manure-based biofertilizer resulted in decreases in salt stress and increases in water use efficiency at 40 DAS, and decreases in leaf temperature and increases in relative chlorophyll content at 54 DAS.

O objetivo deste trabalho foi avaliar o efeito da irrigação com água de alta e baixa salinidade em diferentes turnos de rega e cobertura morta, na cultura do sorgo. O experimento foi conduzido na área experimental da Unidade de Produção de Mudas Auroras (UPMA) da Universidade da Integração Internacional da Lusofonia Afro-Brasileira (UNILAB), com o delineamento inteiramente casualizado, em arranjo fatorial 2 x 2 x 2, sendo dois níveis de condutividade elétrica (A1 - água de abastecimento 0,8 dS m^-1 e A2 – solução salina 4,0 dS m^-1), dois turnos de rega (T1 - turno de rega diário e T2 – turno de rega a cada 4 dias) e, dois tipos de cobertura (Cc – com cobertura morta e Sc - sem cobertura). Foram avaliadas as seguintes variáveis: área foliar (AF), diâmetro do caule (DC), altura da planta (AP), matéria seca da parte aérea (MSPA), potencial hidrogeniônico (pH) e Condutividade elétrica do extrato de saturação (CEes). A cobertura ajuda a minimizar os efeitos da irrigação com água de baixa e alta salinidade, para todas as variáveis analisadas. A água salina reduz o diâmetro do caule, mesmo na presença de cobertura morta. Os turnos de rega apresentam maiores valores de área foliar, altura de planta e diâmetro do caule, quando utilizados com cobertura morta.