The response of plants to salt stress is an extremely complex phenomenon that involves morphological, physiological and biochemical changes, modifying the leaf contents of chlorophyll and carotenoids, among others and affecting plant growth, development and production. An experiment was carried out from July 2010 to June 2011, in order to evaluate the contents of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, the chlorophyll a/b ratio and biomass accumulation of shoots and roots of noni plants, when subjected to irrigation and leaching with water of increasing salinity. The experiment was carried out in a greenhouse, at the Center of Agricultural Sciences of the Federal University of Paraíba, in the municipality of Areia-PB, Brazil. Treatments were distributed in randomized blocks, in a 5 × 2 factorial scheme with four replicates and two plants per plot, and corresponded to levels of electrical conductivity of irrigation water (0.5; 1.5; 3.0; 4.5 and 6.0 dS m-1) in pots with and without leaching. The increase in irrigation water salinity impairs the leaf contents of chlorophyll a, b, total chlorophyll, carotenoids and biomass production of noni plants, but to a lesser extent in all the treatments in which same irrigation water was used for leaching.

The monitoring of plants growth constitutes an important activity during the crops formation, including the yellow passion fruit. In this direction, an experiment was carried out in Remigio, Paraiba State, Brazil, to evaluate the effects of saline water irrigation, bovine biofertilizer and potassium on yellow passion fruit growth plants and soil salinity. Treatments were arranged in randomized block with three replications and 12 plants per plot, using factorial design 2 x 2 x 2, relative electrical conductivity of irrigation water of 0.35 to 4.00 dS m

. 2017. Gas exchange and productivity of yellow passion fruit irrigated with saline water and fertilized with potassium and biofertilizer. Cien. Inv. Agr. 44(2): 168-183. The salinity of irrigation water can affect the growth and development of most plants of commercial interest. Aiming to study these aspects in passion fruit culture, an experiment was performed to evaluate the effects of bovine biofertilizer and potassium fertilization on gas exchange and production of the passion fruit 'BRS Giant Yellow' irrigated with non-saline and saline water. The treatments were arranged in randomized blocks with sub-subdivided plots using the 2×(3×5) scheme, which refers to two levels of electrical conductivity of the irrigation water as the main plot (0.35 and 4.00 dS m -1 ) and the combination of three potassic fertilization practices (without fertilization, fertilized with conventional and slow release KCl) with five doses of bovine biofertilizer (0, 25, 50, 75 and 100% of dose of 15 L m -2 ) in the subplots, with three replicates and 12 plants per plot. The physiological variables and the productivity were evaluated in two harvests, and the data were submitted to statistical evaluation of samples repeated in time. The application of bovine biofertilizer and potassium in soil with a sandy texture irrigated with saline water did not inhibit the degenerative effect of the salts on the photosynthetic rates of the plants. The salinity of the irrigation water reduced stomatal conductance, transpiration and net photosynthesis of the plants, but in the second crop, the instantaneous water use efficiency was higher. Although the productivity decreased from the first to the second harvest, the biofertilizer associated with potassic fertilization increased the yield of the crop, which surpassed the average of Brazil, the Brazilian Northeast and the State of Paraiba, Brazil.

The objective of this study was to evaluate the use of sorghum silage, Buffel grass hay and forage palm fodder in the diet of dairy goats by means of performance tests and economic viability of different roughage sources. Eight Anglo-Nubian goats, multiparous, weighing around 40.13 ± 2.76 kg of live weight were used. The experiment lasted 84 days, consisting of four periods of 21 days, distributed in two Latin squares (4x4). The treatments represented by diets with different volumetric sources: SSCF: (sorghum silage+ forage palm+ concentrate); BHCF: (Buffel grass hay + cactus forage+ concentrate); SS: (sorghum silage+ concentrate) and BH: (Buffel grass hay + concentrate). Nutritional intake, digestibility, feed behavior, milk production and chemical composition and economic analysis were evaluated. Animals fed the BHCF diet had higher nutrient intakes and consequently were more productive in fat, protein, lactose, fat free solids and total solids. The BHCF diet led to a higher gross income in Brazilian currency. The safety margin of the SSCF diet presented the highest percentage, with 43.06%, and the BHCF diet, the lowest percentage, of 14.89. The association of forage palm with sorghum silage and Buffel grass hay can be used as a bulky source in lactating goat diets.

SUMMARY This study agronomically evaluated 14 sorghum genotypes in the Brazilian semi-arid region. A randomized complete block design, with the treatments represented by sorghum genotypes and three replicates, was used. The dry matter (DM), plant height (PH), number of live leaves, fresh matter production (FMP), dry matter production (DMP), leaf blade (LB), stem, panicle (PAN), dead material, water accumulation (WA), efficiency of rainwater use (ERU) and carrying capacity (SC) were measured. There was an effect of genotype among all the variables. The genotype with the highest percentage of DM was BRS 655 (26.42%). The genotypes BRS 655, BRS 506, B1141340, 13F04 (1141572) and PONTA NEGRA produced the most FMP, with values of 48,517, 48,500, 44,879, 44,788 and 43,549 kg/ha, respectively. Not only did the genotypes BRS 655, B1141340, 13F04 (1141572), BRS 506 and PONTA NEGRA present the highest DMP, with values of 12,426, 10,344, 9,778, 9,756 and 9,176 kg/ha, respectively, but also the highest values for ERU, WA and SC. There was a significant positive correlation between productive variables (FMP with DMP, PH, ERU and WA) and a nonsignificant negative correlation between morphometric variables (FMP with LB and PAN). A hierarchical formation of four groups was observed, with groups I and III composed of the most productive genotypes. BRS 655 can be recommended for cultivation since this genotype has desirable agronomic characteristics.

The adequate spacing in okra (Abelmoschus esculentus) influences its growth and fruit production. The objective of this study was to evaluate the growth, the leaf composition and okra production in different spacing with and without biofertilizer.

Os estresses salino e hídrico são parte dos principais fatores que limitam a produção agrícola. Em regiões semiáridas, esses estresses são potencializados devido às altas taxas de evapotranspiração e baixa precipitação pluviométricas. Porém, o fornecimento de água por irrigação e nutrientes via adubação pode favorecer a maximização de produção das culturas. Nesse sentido, objetivou-se avaliar o desempenho agronômico e nutricional de sorgo e milheto, submetidos a diferentes lâminas de irrigação e doses crescentes de nitrogênio. A pesquisa foi realizada na Unidade Acadêmica de Serra Talhada-PE. O delineamento experimental foi em blocos casualizados, dispostos em parcelas subdivididas, com quatro repetições, arranjados em esquema fatorial 4 x 4, referentes a 4 lâminas de irrigação (28%, 36%, 44%, 52% ETc) e 4 doses de nitrogênio (0, 100, 200, 300 kg ha-1), adotando o sistema Sorgo + Millet, sendo o sorgo a cultura principal. A semeadura foi realizada em 7 de abril de 2017, com média de 14 plantas por linear. As lâminas de irrigação foram baseadas na ETc (ETc = ETo x Kc do sorgo). A adubação nitrogenada consistiu no parcelamento de 1/3 na semeadura e 2/3 na cobertura. Ao final de cada ciclo da cultura, a altura da planta e o diâmetro do caule foram medidos, o número de folhas vivas foi contado, a produção de massa verde e seca foi estimada, o teor de N-total, Na+, K+ e Cl- foram determinados. Os dados foram submetidos à análise de variância e as variáveis ​​ajustadas ao modelo de regressão, por meio do software SAS. A adubação nitrogenada e a irrigação com água salina beneficiaram o crescimento da cultura do sorgo e do milheto. O nitrogênio favorece a absorção de N-total e potássio pelas plantas e inibe a absorção de cloreto e sódio.

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