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The use of saline waters in agriculture has become an alternative for the expansion of irrigated agriculture in the semiarid regions. However, it is necessary to develop techniques capable of mitigating the effects of stress caused by excess salts on plants. In this context, the objective of present study was to evaluate the growth and production of cotton cv. BRS Jady irrigated with waters of increasing levels of salinities and doses of organic fertilization. The experiment was conducted using a Regolith Neosol of a sandy-loamy texture in a greenhouse in the municipality of Campina Grande – PB. The experimental design was a randomized block design, in a 4 x 4 factorial scheme, with three replications, being the treatments composed of four levels of electrical conductivity of water (ECw, 1.7, 3.4, 5.1 and 6, 8 dS m-1) and four doses of organic fertilization (0, 2.5, 3.5 and 4.5% on the basis of soil volume). Water salinity of up to 6.8 dS m- 1 reduces relative growth rates, specific leaf area, leaf area ratio and harvest index of cotton cv. BRS Jady. Organic fertilization attenuates the effects of irrigation water salts on the net assimilation rate and total dry mass of cotton cv. BRS Jady, with a dose of 4.5% MO showing the best results. [ABSTRACT FROM AUTHOR]

Salt stress suffered by plants due to concentration of irrigation water salts reduces the ability of exploitation of cultures especially in arid and semiarid regions. Thus, the aim of this study was to evaluate the effect of salinity of irrigation water on the growth of rootstock of guava 'Crioula' associated with increasing doses of nitrogen fertilizer. The experiment was conducted in plastic pots under greenhouse conditions in the CCTA / UFCG. We used the experimental randomized block design, with the treatments in a factorial 5 × 4, corresponding to five levels of electrical conductivity of the water - CEa (0.3; 1.1; 1.9; 2.7 and 3.5 dS m-1) and four nitrogen rates (70, 100, 130 and 160% of the recommended dose N for guava cultivation seedlings cv. Paluma) with 4 replications and 5 plants per plot. The dose of 70 % of N- ( 541.1 mg N dm-1 of soil ) provides greater production plant leaf area, height 145 DAE, but to stem diameter was significant in both periods studied the rootstock guava cv. Crioula. Irrigation CEa above 0.3 dS m-1 negatively affect the number of leaves, leaf area, stem diameter, leaf area ratio and absolute growth rate of stem diameter. There was interaction between the factors salinity of irrigation water and nitrogen fertilization for variable number of leaves at 145 DAE rootstock of guava "Crioula". [ABSTRACT FROM AUTHOR]

The effects of salts in the soil, causing variations in structure, permeability and aeration of the soil indirectly affect the growth of plants. Thus the increased nitrogen dosing as an isolated factor, can promote greater efficiency in the production of seedlings. In this sense, the aim of this work was to analyze the influence of irrigation water salinity associated with increasing doses of nitrogen on the development of rootstock of guava genotypes 'Crioula'. The experiment was conducted in plastic pots under greenhouse conditions in the CCTA / UFCG. We used the experimental randomized block design, with the treatments in a factorial 5 x 4, corresponding to five levels of electrical conductivity of the water - CEa (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four nitrogen rates (70, 100, 130 and 160% of the recommended dose N for guava cultivation seedlings cv. Paluma) with 4 replications and 5 plants per plot. There was no significant interaction between the factors salinity of irrigation water and nitrogen fertilization on growth rootstock genotype of guava "Crioula". Increased CEa from 0.3 dS m-1 affects negatively and linearly stem diameter (DC), number of leaves (NF), absolute growth rate (TCAAP) and relative plant height (TCRap), the height growth balance of plant / stem thickness and dry mass export of the sheet for the rest of the plant (RMF). The dose of 70% of N (541.1 mg N dm-1 soil) provides higher values of DC, NC, TCAap and TCRap rootstock of guava "Crioula". [ABSTRACT FROM AUTHOR]

Salinity has limited conventional vegetable cultivation, especially in semi-arid regions. In this regard, the use of elicitors that act to induce tolerance to salt stress, such as salicylic acid, has emerged as a promising alternative. This study evaluated the effects of foliar spraying with salicylic acid on the mitigation of salt stress on the morphophysiology and production of bell pepper cv. All Big. The study was conducted in a greenhouse in Campina Grande - PB, Brazil, adopting a completely randomized design, in a 4 x 4 factorial arrangement, corresponding to four levels of electrical conductivity of irrigation water (0.8; 1.6; 2.4; and 3.2 dS m-1) and four concentrations of salicylic acid (0; 1.2; 2.4 and 3.6 mM), with three replicates. The foliar application of salicylic acid at a concentration of 1.6 mM attenuated the effects of salt stress in gas exchange, growth, mean fruit weight, and total production per plant, and decreased the percentage of intercellular electrolyte leakage of sweet pepper cv. All Big plants, at 80 days after sowing. [ABSTRACT FROM AUTHOR]

The irrigation with saline water reduces crop growth and yield, resulting in the need of new techniques that enable the use of this natural resource in fruit growing. In this sense, the objective of this study was to evaluate the effect of saline irrigation water associated with different nitrogen doses on guava rootstock cv. Paluma morphophysiology. The experiment was carried out in a completely randomized blocks design, testing 5 electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four nitrogen doses for fertilization (541.1; 773.0; 1004.9 and 1236.8 mg dm-3), in a 5x4 factorial, with four repetitions. The increase in the ECw from 0.3 dS m-1 negatively affected the morphophysiology of guava rootstock cv. Paluma, especially during the younger phase of the crop. The N dose of 541 mg dm-3 stimulated the increase of most morphophysiological variables in guava rootstock during the period studied. The nitrogen fertilization did not reduced the salt stress effect on the evaluated variables. [ABSTRACT FROM AUTHOR]

Our planet isflooded withwater, butonly 0.3% 105 km3 is fresh waterand isstoredin rivers and lakes; And thatamount of waterwhich is usuallyused for human consumption, animal andagricultural.Todaydue to themisuse ofwaterthe planetlive theso-called water crisis. Faced with thecrisisof such an importantandvital resourcefor everyone, the UNdecided toaddress the issuethrough reports (on Development of Water Resources) to raise awarenessof the worldabout theneed to observethe issue ofwater security. Accordingly made worrying forecasts for 2050 highlightingthe growing globalwater demandin the sectors ofmanufacturingand agriculture.All this demandcan causea waterunprecedentedcollapsebeforeitbecomes necessaryplanning.A consciousand efficient managementofwater resourcesto ensureto all, especially the poorest, progress ineach of the threedimensions of sustainable development: social development, economic development andenvironmental development. Ensuring the development along these lines the water can be a decisive instrument in combating poverty and maintaining a more balanced and harmonious planet. [ABSTRACT FROM AUTHOR]

Fixing the man in the regions of the planet has happened in terms of availability of information required for their survival. In this sense, water has been the form of energy essential to life and the maintenance of ecosystems. Howeverits scarcity has becomea problemofglobalorder sothat governmentshavebecome increasinglyconcerned withmanagingthis resourceresponsibly.The growing demand forwater hasmadetheplannedreusea current topicof great importance.In this sense, it is considered thewater reuseas partof a broaderactivity that isrationalandefficient use of water, which also includesthecontrol of lossesand waste, and minimizingwaste productionandwater consumption.The use ofwastewaterforvarious purposesis already a realityinseveral countries.In Brazil, among the main factors thatcontributed to theincreasedinterest inirrigation withwastewater, are: water scarcity, technical and scientificadvancement, the most rigorousand activeenvironmental legislation, greater control ofenvironmental pollution,decreasetreatment costswithsoildue to the action, provisionand supply ofnutrientsand organic matterto plants, reducing the cost ofcommercialfertilizers.This makes itpossible to conclude thatwater reuseis importantrationalmanagement toolof water resources,with regardtowater reusefor agricultural purposes. [ABSTRACT FROM AUTHOR]

In addition to favoring the development and production of crops, the fertilizer has been considered a technique capable to reduce the effect of salinity on plants. The experiment was conducted in a greenhouse of the 'Centro de Ciências e Tecnologia Agroalimentar' of UFCG, Pombal, PB in a randomized block design a 5 x 4 factorial, with the treatments corresponding to the electrical conductivity of irrigation water (ECw) 0.3; 1.1; 1.9; 2.7 and 3.5 dS m-1 associated with doses of 70, 100, 130 and 160% of recommended nitrogen (N) for guava seedlings Paluma, with four replications, using five plants per experimental unit. At 180 days after emergence, the nitrogen fertilization at a dose of 773 mg N dm-3 reduces the effect of irrigation water salinity on the stem diameter of seedlings . The plants fertilized with doses ranging from 541 at 618.4 mg of the N dm-3 reach higher growth in plant height, leaf number and leaf area. The leaf area and total dry mass of guava seedlings reach higher values at the ECw level of 1.3 dS m-1. [ABSTRACT FROM AUTHOR]

The research was conducted in protected environment in the CCTA / UFCG which aimed to evaluate the growth of naturally colored hp fiber cotton plants. BRS Topaz, the second post-pruning production cycle in saline-sodic soils manure. It used the randomized block design in a factorial 5 x 4, with 3 repetitions and the treatments consisted of five percentages of exchangeable sodium - PST (13.6; 22.4; 30.1; 39.0 and 48.0 %) and four doses of cattle manure (0, 5, 10 and 15%). To cease production of cotton plants (first cycle) held a drastic pruning, where, after the shoots (second cycle) were evaluated after 51 and 91 days after pruning (DAP) variables: branch length (CR), branch diameter (DR), stem diameter (DC) and number of leaves (NF). Doses of 10% organic matter favored branch length and 15% of the diameter of the branch and cotton plants cv stem. BRS Topaz after 51 and 91 days after pruning. Exchangeable sodium in percentages of up to 48% did not influence the length and diameter of branches, the stem diameter and the number of cotton leaves at 51 and 91 days after pruning. The interaction between the factors (PST x MO) has promoted significant effect on stem diameter of cotton plants at 91 DAP. [ABSTRACT FROM AUTHOR]

Cashew is a fruit species of great economic importance in Brazil, especially in its Northeast region. However, abiotic factors such as water and soil salinity stand out as limiting parameters for this crop, affecting all phases of development as well as physiological and biochemical processes. In this scenario, the use of products to mitigate such damage becomes a necessary practice, with silicon and potassium being viable alternatives. From this perspective, the present study aimed to evaluate the photochemical efficiency of cashew rootstocks subjected to water salinity and foliar application of potassium silicate. A randomized block design arranged in a 5x5 factorial with four replications and two plants per plot was used in the experiment. Treatments consisted of different levels of irrigation water electrical conductivity - ECw (0.3, 1, 1.7, 2.4, and 3.1 dS m-1) and potassium silicate concentrations (0, 250, 500, 750, and 1000 mg L-1) supplied via foliar application. Irrigation water salinity levels from 2.1 dS m-1 reduce the photochemical efficiency of photosystem II by at least 10%, consequently affecting the photosynthetic apparatus of cashew plants 70 days after sowing. The potassium silicate concentration of 250 mg L-1 increases the quantum yield of cashew plants under salt stress conditions. [ABSTRACT FROM AUTHOR]

This research aimed to evaluate the physiological indices and the accumulation of phytomass in clones of precocious dwarf cashew under salt stress during rootstock formation. The experiment was conducted in greenhouse in the municipality of Pombal-PB. The experimental design was in randomized blocks, and the treatments were organized in a 5 x 3 factorial arrangement, constituting the levels of electrical conductivity of the irrigation water - ECw (0.4 -Control; 1.2; 2.0; 2.8, and 3.6 dS m-1) and the clones of precocious dwarf cashew (Faga 11, Embrapa 51, CCP 76), with three replications and two plants per plot. Water salinity higher than 0.4 dS m-1 resulted in a decrease of the relative growth in plant height, leaf area, and phytomass accumulation in the cashew plant. The cashew clones are sensitive to water salinity from 0.4 dS m-1. Among the physiological indicators, the leaf area ratio, the sclerophylly index, and the root/shoot ratio of the precocious dwarf cashew are highlighted as salt stress indicators. The use of water with 0.4 dS m-1 of electrical conductivity is recommended for the formation of cashew rootstocks. [ABSTRACT FROM AUTHOR]

Exogenous application of H2O2 has established efficiency in acclimatization of plants to biotic and abiotic stresses due to stimulate the activation of antioxidant defense system. In this context, it was aimed with this work evaluate the effect of application method of different concentrations of H2O2 on initial growth of maize plants irrigated saline water. The experiment was conducted in a greenhouse, with the treatments in a randomized completely design in a factorial 5 x 2 corresponding the hydrogen peroxide concentrations (H2O2) 0; 5; 10; 15:20 μmol L-1 applied in sowing by irrigation water and foliar spray at 15 days after sowing (DAS), with four repetitions and experimental unit consisting of vessel a 3 L containing two plants hybrid maize 4051. The plants were irrigated with EC water of 2.0 dS m-1. The 28 DAS it was found what the application H2O2 at sowing and foliar spraying promote acclimatization of maize plants at salinity irrigation water, increasing tolerance to salt stress. The more initial growth of maize is obtained in H2O2 concentrations ranging from 7 to 8 μmol L-1, being more efficient the application at sowing. The pretreatment of maize plants with H2O2 from 15 μmol L-1 increasing stress, promoting further damage to vegetative growth. [ABSTRACT FROM AUTHOR]