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The growing need to increase food production constitutes a serious scientific-technological challenge, requiring the expansion of cultivated sites also with the utilization of degraded areas, such as soils affected by salts. In order to achieve that, alternatives to mitigate such limitations have been pursued, such as the use of biofertilizers in the formation process of neem seedlings. In the pursuit for alternative and ecological control methods considered healthy and sustainable, the use of the neem tree (Azadirachta indica) associated with organic inputs in semiarid regions is highlighted, since this species possesses azadirachtin as the main bioactive compound, capable of acting against more than 418 plague species due to its insecticidal properties. An experiment was conducted in a screened plant nursery in the municipality of Areia – PB, in the period from January to July 2016, to evaluate the effects of the supplemental irrigation with saline waters on the absolute growth of neem seedlings in soil with biofertilizer. The substrate was a Dystrophic Red- Yellow Latosol. The experimental design was in randomized blocks, in a 5x2x3 factorial scheme, with four replications. The treatments were irrigated with five levels of water salinity (0.5; 1.5; 3.0; 4.5; 6.0 dS m-1), in the soil without and with common fermented bovine biofertilizer, and evaluated after three periods: 30, 60, and 90 days after the emergence of the plantlets, for the determination of the absolute growth in AP, DC, IAF, MSR, MSPA, and MST. The liquid fermented biofertilizer, after diluted, was applied a single time in a 1:3 proportion, two days before sowing, at the level of 10% the volume of the substrate. The treatments with fermented bovine biofertilizer provided better conditions for the growth and development of the neem through osmotic effect than in the soil without the input as a function of the time.

The salinity is considered the major constraint to agriculture worldwide, constituting a limiting factor to growth, plant development, agricultural productivity and soil deterioration. In this direction an experiment was carried out during the period October/2009 to February/2010, in greenhouse conditions in Areia county, Paraiba State, PB, Brazil, in order to evaluate the effects of water saline on initial growth of papaya Hawaii in non-saline substrate with bovine rich biofertilizer. The substrate was material of the first 0.10 m of a Regolitic Entisol non saline. The treatments were distributed in completely randomized in six replication using the factorial design 5 x 2, corresponding to levels of irrigation water saline: 0.5; 1.0; 2.0; 3.0 and 4.0 dS m-1, in soil without and with rich biofertilizer applied to soil in liquid form one time two days before seed sowing, at level of 10% of the substrate volume. The increment of salinity water irrigation inhibited alls variables studied in papaya’s plants, but with less range in treatments with bovine biofertilizer.A salinidade é considerada um dos principais entraves para agricultura em todo mundo, constituindose num dos fatores limitantes ao crescimento, desenvolvimento das plantas, produtividade agrícola e depauperamento do solo. Nesse sentido, um experimento foi desenvolvido no período de Outubro de 2009 a Fevereiro de 2010, em ambiente telado, no município de Areia – PB, para avaliar a influência da salinidade da água de irrigação no crescimento do mamão Havaí em substrato não salino com biofertilizante rico. O substrato utilizado foi o material dos primeiros 0,10 m de um NEOSSOLO REGOLITICO não salino. O delineamento experimental foi inteiramente casualizado em esquema fatorial 5 x 2, referente aos valores de condutividade elétrica da água de irrigação: 0,5; 1,0; 2,0; 3,0 e 4,0 dS m-1, em solo sem e com biofertilizante líquido, com seis repetições. O biofertilizante rico, depois de diluído em água não salina (0,5 dS m-1) na razão de 1:1 foi aplicado uma única vez, dois dias antes da semeadura, em nível de 10% do volume do substrato. O aumento da salinidade da água de irrigação provocou perdas sobre todas as variáveis avaliadas nas plantas, mas com menor intensidade nos tratamentos com biofertilizante.

The agricultural use of wastewater generated in the processing of cashew nuts enables the rationalization of water use, as well as the minimization of pollution and environmental degradation. The study aimed to analyze the effect of service pressures in the distribution uniformity of drip irrigation units applying treated wastewater from cashew nut industry. The experiment was conducted in split-split plots scheme having the service pressures (70, 140, 210 and 280 kPa) on parcels, the emitters models (G1, G2 and G3) on subplots and the evaluation periods (0, 20, 40, 60, 80, 100, 120, 140 and 160 h of operation of the irrigation units) on subsubplots. The treatments were distributed in a completely randomized design with three replications. The coefficient of uniformity of distribution of irrigation units, as well as the physical, chemical and microbiological characteristics of the effluent were determined every 20 hours of operation the irrigation units to totalize 160 h. The combination of dripper G3 and service pressure of 140 kPa provided excellent levels of distribution uniformity of effluent on irrigation units operating with treated wastewater of cashew nut industry. For application of treated wastewater from cashew nut it is not recommended the use of drippers with low flow rate (? 1.6 L h-1) and labyrinth of greater length (? 58 mm).

Water is a basic natural resource for the maintenance of life and is indispensable in all human activities. Since it is a limited natural resource, concern on the conservation of its quality is high, coupled with efficacious mechanisms that may diminish negative environmental impacts. Current analysis applies the Water Quality Index (WQI) for hydraulic barriers in the urban stretch of Mossoro RN Brazil and verifies the water body conditions according to usage classes, with special reference to predominant factors and previous classification of the water body. Collection of water for analysis of WQI parameters was undertaken in July 2010 in three barriers within the urban stretch and geo-referenced for the indication of critical sites. Possible exploratory activities linked to the contamination of the water body were listed. An evaluation of rates was undertaken and compared with current legislation guidelines. According to CONAMA n. 357/2005, results showed that analyses during the dry period referred to the salinity of the water body when related to preponderant usage indexes, or Class 1. Total phosphorus failed to comply with rates when parameters were analyzed one by one and compared to standards established by CONAMA n. 357/2005. Water was of good quality at the first barrier and fair in the others from the entrance of the city and downstream, due to the great load of home effluents, agro-industrial wastes and surface runoff.