This study aimed to evaluate combinations of cowpea-vegetable cultivars with carrot cultivars in a strip-intercropping system fertilized with roostertree. The work was conducted at the Experimental Farm "Rafael Fernandes" of the Universidade Federal Rural do Semi-Árido (UFERSA) during September 2013 to March 2014. The experimental design was a randomized complete block with four replications and treatments arranged in a factorial 4 x 2 scheme, resulting from the combination of four cowpea -vegetable cultivars (BRS Tumucumaque, BRS Cauamé, BRS Guariba and BRS Itaim) with two carrot cultivars (Brasilia and Alvorada). The characteristics evaluated in cowpea-vegetables were: number of green pods per area, productivity and dry weight of green pods, number of grains per pod, productivity of grains, weight of 100 grains, and dry weight of green grains. In the carrot cultivars, we evaluated total, commercial, and classified productivity of roots. The cultivar combinations were evaluated in terms of land equivalent ratio, productive efficiency index, score of the canonical variable, as well as indicators of gross and net income, rate of return, profit margin, and modified monetary advantage. The intercropping system using the cultivars BRS Guariba (cowpea) and Alvorada (carrot) achieved highest agronomic/biological efficiency. Highest economic efficiency was achieved with the combination BRS Tumucumaque (cowpea) and Brasilia (carrot).

ABSTRACT This study aimed to evaluate combinations of cowpea-vegetable cultivars with carrot cultivars in a strip-intercropping system fertilized with roostertree. The work was conducted at the Experimental Farm "Rafael Fernandes" of the Universidade Federal Rural do Semi-Árido (UFERSA) during September 2013 to March 2014. The experimental design was a randomized complete block with four replications and treatments arranged in a factorial 4 x 2 scheme, resulting from the combination of four cowpea -vegetable cultivars (BRS Tumucumaque, BRS Cauamé, BRS Guariba and BRS Itaim) with two carrot cultivars (Brasilia and Alvorada). The characteristics evaluated in cowpea-vegetables were: number of green pods per area, productivity and dry weight of green pods, number of grains per pod, productivity of grains, weight of 100 grains, and dry weight of green grains. In the carrot cultivars, we evaluated total, commercial, and classified productivity of roots. The cultivar combinations were evaluated in terms of land equivalent ratio, productive efficiency index, score of the canonical variable, as well as indicators of gross and net income, rate of return, profit margin, and modified monetary advantage. The intercropping system using the cultivars BRS Guariba (cowpea) and Alvorada (carrot) achieved highest agronomic/biological efficiency. Highest economic efficiency was achieved with the combination BRS Tumucumaque (cowpea) and Brasilia (carrot). | RESUMO Este estudo teve como objetivo avaliar combinações de cultivares de caupi-horaliça com cultivares de cenoura em sistema consorciado em faixas adubadas com flor-de-seda. O trabalho foi conduzido na Fazenda Experimental “Rafael Fernandes” da Universidade Federal Rural do Semi-Árido (UFERSA), durante o período de setembro de 2013 a março de 2014. O delineamento experimental utilizado foi o de blocos completos casualizados com 4 repetições e os tratamentos arranjados em esquema fatorial 4 x 2, resultante da combinação de quatro cultivares de caupi (BRS Tumucumaque, BRS Cauamé, BRS Guariba e BRS Itaim) com duas cultivares de cenoura (Brasília e Alvorada). As características avaliadas no caupi-hortaliça foram: número de vagens verdes por área, produtividade e peso seco de vagens verdes, número de grãos por vagem, produtividade de grãos, peso de 100 grãos e peso seco de grãos verdes. Nas cultivares de cenoura foram avaliadas: as produtividades total, comercial e classificada de raízes. As combinações de cultivares foram avaliadas pelo índice de uso eficiente da terra, índice de eficiência produtiva, escore da variável canônica e pelos indicadores rendas bruta e líquida, taxa de retorno, índice de lucratividade e vantagem monetária corrigida. O sistema de consórcio utilizando as cultivares de caupi BRS Guariba e a de cenoura Alvorada obteve maior eficiência agronômica/biológica. A maior eficiência econômica foi obtida com a combinação de caupi BRS Tumucumaque e cenoura Brasília.

Wood, in general, is a material with excellent properties; however, some features may limit its use. In this sense, various thermal treatments are emerging as alternatives to improve the technological properties of wood. In this context, this study aims at analyzing the effects of time and temperature (hydrothermal treatment and freezing) on the physical and mechanical properties of Eucalyptus grandis W. Hill ex Maiden. Three trees were selected, and only the heartwood was used to obtain the test body dimensions of 30 × 8 × 3 cm (length × width × thickness). The treatments were carried out at three temperatures of -20, 60, and 100°C, each at three exposure times (5, 10, and 15 h). Temperature treatment at -20°C was conducted in a domestic freezer, while the treatments at 60 and 100°C were administered in a Parr reactor, where the timber was submerged in water. Regardless of the exposure time, the timbers heat-treated at 100°C showed more efficiency, since this treatment unclogged the pores, reduced hygroscopicity, and promoted further darkening and uniformity of color, without changing the density and mechanical strength of the wood.

ABSTRACT Wood, in general, is a material with excellent properties; however, some features may limit its use. In this sense, various thermal treatments are emerging as alternatives to improve the technological properties of wood. In this context, this study aims at analyzing the effects of time and temperature (hydrothermal treatment and freezing) on the physical and mechanical properties of Eucalyptus grandis W. Hill ex Maiden. Three trees were selected, and only the heartwood was used to obtain the test body dimensions of 30 × 8 × 3 cm (length × width × thickness). The treatments were carried out at three temperatures of -20, 60, and 100°C, each at three exposure times (5, 10, and 15 h). Temperature treatment at -20°C was conducted in a domestic freezer, while the treatments at 60 and 100°C were administered in a Parr reactor, where the timber was submerged in water. Regardless of the exposure time, the timbers heat-treated at 100°C showed more efficiency, since this treatment unclogged the pores, reduced hygroscopicity, and promoted further darkening and uniformity of color, without changing the density and mechanical strength of the wood. | RESUMO A madeira, de modo geral, é um material com excelentes propriedades, mas ressalta-se que algumas características podem limitar o seu uso. Neste sentido, alguns métodos de tratamentos térmicos vêm surgindo como alternativa para melhorar algumas propriedades tecnológicas da madeira. Neste contexto, o objetivo do trabalho foi avaliar o efeito do tempo e da temperatura do tratamento hidrotérmico e do congelamento nas propriedades físicas e mecânicas da madeira de Eucalyptus grandis W.Hill ex Maiden. Foram utilizadas três árvores, selecionando-se apenas a madeira do cerne para obtenção dos corpos de prova de dimensões 30 x 8 x 3 cm (comprimento x largura x espessura). Os tratamentos foram realizados nas temperaturas de -20, 60 e 100 °C combinados a três tempos de exposição (5, 10 e 15 horas). O tratamento na temperatura de -20 °C foi realizado em um freezer doméstico, e os tratamentos a 60 e 100 °C em um Reator Parr, onde as madeiras ficaram submersas em água. Independente do tempo de exposição, os tratamentos realizados a 100 °C mostraram-se mais eficientes, pois desobstruíram os poros, reduziram a higroscopicidade e promoveram maior escurecimento e homogeneização da cor das madeiras, sem alterar a densidade e a resistência mecânica das mesmas.

The objective of this work was to evaluate the effect of applying mixtures of chemical ripeners on the technological quality and agricultural productivity of sugarcane. The experimental design consisted of randomized blocks arranged in split- split-plots with four blocks, the main plots being constituted by sugarcane varieties SP803280 and SP801842. The subplots consisted of the application of the following products with their respective mixtures: control - absence of ripener; Sulfometrom methyl + glyphosate; ethephon + glyphosate; glyphosate and compounds of organic carboxylic radicals + glyphosate. The sub-subplots were composed of evaluation times: 0; 15 and 30 days after applying the products. Samples from each plot were collected manually and sent to the laboratory for the determination of soluble Brix solids (% broth); Sucrose content in the broth - Pol (% broth); Reducing sugars (RS%); Total reducing sugars (TRS%); Fiber (%); Purity (%); Humidity (%) and Total recoverable sugar TRS (kg t-1). The plots were fully harvested and the stems were taken for weighing and for characteristics determination: Yield per hectare (TCH) and Yield of sugar per hectare (TAH). The SP803280 variety was more responsive to the use of mixtures of chemical ripeners. For the technological characteristics, sulfometurom methyl (0.02 kg ha-1) + glyphosate (0.15 L ha-1) presented the best results from 15 days after application. Mixtures of chemical ripeners did not increase the yields of stalks and sugar per area.

ABSTRACT The objective of this work was to evaluate the effect of applying mixtures of chemical ripeners on the technological quality and agricultural productivity of sugarcane. The experimental design consisted of randomized blocks arranged in split- split-plots with four blocks, the main plots being constituted by sugarcane varieties SP803280 and SP801842. The subplots consisted of the application of the following products with their respective mixtures: control - absence of ripener; Sulfometrom methyl + glyphosate; ethephon + glyphosate; glyphosate and compounds of organic carboxylic radicals + glyphosate. The sub-subplots were composed of evaluation times: 0; 15 and 30 days after applying the products. Samples from each plot were collected manually and sent to the laboratory for the determination of soluble Brix solids (% broth); Sucrose content in the broth - Pol (% broth); Reducing sugars (RS%); Total reducing sugars (TRS%); Fiber (%); Purity (%); Humidity (%) and Total recoverable sugar TRS (kg t-1). The plots were fully harvested and the stems were taken for weighing and for characteristics determination: Yield per hectare (TCH) and Yield of sugar per hectare (TAH). The SP803280 variety was more responsive to the use of mixtures of chemical ripeners. For the technological characteristics, sulfometurom methyl (0.02 kg ha-1) + glyphosate (0.15 L ha-1) presented the best results from 15 days after application. Mixtures of chemical ripeners did not increase the yields of stalks and sugar per area. | RESUMO O objetivo deste trabalho foi avaliar a aplicação das misturas de maturadores químicos na qualidade tecnológica e produtividade agrícola da cana-de-açúcar . Foi utilizado o delineamento experimental em blocos casualizados arranjados em parcelas sub-subdivididas com 4 blocos, sendo as parcelas principais constituídas pelas variedades de cana-de-açúcar: SP803280 e SP801842. As subparcelas consistiram da aplicação dos seguintes produtos com suas respectivas misturas: controle - ausência de maturador; sulfometurom metil + glifosato; etefon + glifosato; glifosato e compostos de radicais carboxílicos orgânicos + glifosato. As sub-subparcelas foram constituídas de épocas de avaliação: 0; 15 e 30 dias após as aplicações dos produtos. As amostras de cada parcela foram colhidas manualmente e encaminhadas ao laboratório para determinação dos sólidos solúveis Brix (% caldo); teor de sacarose no caldo - Pol (% caldo); Açúcares redutores (AR%); Açúcares redutores totais (ART%); Fibra (%); Pureza (%); Umidade (%) e Açúcar total recuperável ATR (kg t-1). As parcelas foram totalmente colhidas e os colmos despontados para pesagem e para a determinação das características: Rendimento de colmos por hectare (TCH) e Rendimento de açúcar por hectare (TAH). A variedade SP803280 destacou-se como mais responsiva ao uso das misturas de maturadores químicos. Para as características tecnológicas, a mistura sulfometurom metil (0,02 kg ha-1) + glifosato (0,15 L ha-1) apresentou os melhores resultados a partir dos 15 dias após a sua aplicação. As misturas de maturadores químicos não proporcionaram aumentos de produtividade de colmos e açúcar por área.

The objective of this study was to evaluate combinations of coriander and salad rocket cultivars in bicropping systems intercropped with carrot cultivars in strips under the conditions of Mossoró-RN. The work was conducted at the Experimental Farm Rafael Fernandes from July to December 2014. The experimental design was a randomized complete block design with four replications and treatments arranged in a factorial design with additional treatments of type 2 x 2 x 2 + 2. The treatments consisted of the combinations of two coriander cultivars (Verdão and Português) and two rocket cultivars (Cultivada and Folha Larga), intercropped with two carrot cultivars (Brasília and Esplanada) plus two additional treatments, where the first are the cultivars in monocropping and the second the types of cropping (single and intercropped). We evaluated fresh and dry shoot mass in coriander and rocket and fresh and dry shoot mass as well as dry root mass, commercial and total root productivity, and classified root productivity in carrot. In the intercropping systems we evaluated land equivalent ratio, productive efficiency index, and score of the canonical variable, besides the indicators of economic efficiency (gross income, net income, rate of return and profit margin). Highest agroeconomic efficiency in intercropping systems was achieved with the combination of the coriander cultivar 'Verdão' and the rocket cultivars 'Folha Larga' or 'Cultivada' as well as the carrot cultivars 'Brasília' or 'Esplanada'. Regardless of the tested cultivar combinations, systems with coriander and salad rocket intercropped with carrot showed higher efficiency than monocropping systems.

ABSTRACT The objective of this study was to evaluate combinations of coriander and salad rocket cultivars in bicropping systems intercropped with carrot cultivars in strips under the conditions of Mossoró-RN. The work was conducted at the Experimental Farm Rafael Fernandes from July to December 2014. The experimental design was a randomized complete block design with four replications and treatments arranged in a factorial design with additional treatments of type 2 x 2 x 2 + 2. The treatments consisted of the combinations of two coriander cultivars (Verdão and Português) and two rocket cultivars (Cultivada and Folha Larga), intercropped with two carrot cultivars (Brasília and Esplanada) plus two additional treatments, where the first are the cultivars in monocropping and the second the types of cropping (single and intercropped). We evaluated fresh and dry shoot mass in coriander and rocket and fresh and dry shoot mass as well as dry root mass, commercial and total root productivity, and classified root productivity in carrot. In the intercropping systems we evaluated land equivalent ratio, productive efficiency index, and score of the canonical variable, besides the indicators of economic efficiency (gross income, net income, rate of return and profit margin). Highest agroeconomic efficiency in intercropping systems was achieved with the combination of the coriander cultivar 'Verdão' and the rocket cultivars 'Folha Larga' or 'Cultivada' as well as the carrot cultivars 'Brasília' or 'Esplanada'. Regardless of the tested cultivar combinations, systems with coriander and salad rocket intercropped with carrot showed higher efficiency than monocropping systems. | RESUMO O objetivo deste trabalho foi avaliar combinações de cultivares de coentro e rúcula em bicultivo consorciadas com cultivares de cenoura em faixas, nas condições de Mossoró - RN. O trabalho foi realizado na Fazenda Experimental Rafael Fernandes de julho a dezembro de 2014. O delineamento experimental foi em blocos completos casualizados, com quatro repetições e os tratamentos arranjados em um esquema fatorial com tratamentos adicionais do tipo 2 x 2 x 2 + 2. Os tratamentos consistiram da combinação de duas cultivares de coentro (Verdão e Português) e duas cultivares de rúcula (Cultivada e Folha Larga), consorciadas com duas cultivares de cenoura (Brasília e da Esplanada), mais dois tratamentos adicionais, onde o primeiro são as cultivares em monocultivo e o segundo os sistemas de cultivo (solteiro e consorciado). Foram avaliadas massa fresca e seca da parte aérea em coentro e rúcula e massa fresca e seca da parte aérea, bem como, massa de raízes seca, produtividade de raízes comercial e total e produtividade de raízes classificadas na cenoura. No sistema de consórcio avaliaram-se: índice de uso eficiente da terra, índice de eficiência produtiva, e escore da variável canônica, além dos indicadores de eficiência econômica (renda bruta, renda líquido, taxa de retorno e índice de lucratividade). A maior eficiência agroeconômica nos sistemas consorciados foi conseguida com a combinação da cultivar de coentro 'Verdão' e as cultivares de rúcula 'Folha Larga' ou 'Cultivada', bem como, as cultivares de cenoura 'Brasília' ou 'Esplanada'. Independentemente das combinações das cultivares testadas, sistemas com coentro e rúcula em consórcio com cenoura mostraram maior eficiência do que os monocultivos.

The N:K ratio influences the balance between vegetative and reproductive stages, because potassium plays important roles in the processes that regulate plant growth when the nitrogen availability is high. However, there is a lack of information on the N:K ratio suitable for cucumber cultivation in an NFT-hydroponic system. The objective of this study is to evaluate the different N:K ratios in fruiting nutrient solutions for cucumber production in a hydroponic system. Treatments consisted of two cucumber hybrids (Natsuno Kagayaki and Runner) and four nutrition solutions with different N:K ratios (w/w) (1:0.5, 1:1.0, 1:2.0, and 1:3.0) in the reproductive phase arranged as split plots in a randomized block design with four replications. On the 33rd day after sowing (DAS), the SPAD index on the fourth expanded leaf from the plant apex, number of broaches, and harvests were evaluated. The aerial parts of the plants were collected on the 54th DAS for evaluation of fresh mass, dry mass, and number of leaves per plant. The results showed that the highest concentration of K in the fruiting nutrient solution does not alter the length of the fruits but increases their diameter yield. The N:K ratios in the 1:2.0 and 1:3.0 (w/w) nutrient solutions provided greater yields in both evaluated hybrids. The hybrid Natsuno Kagayaki, however, showed the highest productivity, and it is recommended for hydroponic cultivation.

ABSTRACT The N:K ratio influences the balance between vegetative and reproductive stages, because potassium plays important roles in the processes that regulate plant growth when the nitrogen availability is high. However, there is a lack of information on the N:K ratio suitable for cucumber cultivation in an NFT-hydroponic system. The objective of this study is to evaluate the different N:K ratios in fruiting nutrient solutions for cucumber production in a hydroponic system. Treatments consisted of two cucumber hybrids (Natsuno Kagayaki and Runner) and four nutrition solutions with different N:K ratios (w/w) (1:0.5, 1:1.0, 1:2.0, and 1:3.0) in the reproductive phase arranged as split plots in a randomized block design with four replications. On the 33rd day after sowing (DAS), the SPAD index on the fourth expanded leaf from the plant apex, number of broaches, and harvests were evaluated. The aerial parts of the plants were collected on the 54th DAS for evaluation of fresh mass, dry mass, and number of leaves per plant. The results showed that the highest concentration of K in the fruiting nutrient solution does not alter the length of the fruits but increases their diameter yield. The N:K ratios in the 1:2.0 and 1:3.0 (w/w) nutrient solutions provided greater yields in both evaluated hybrids. The hybrid Natsuno Kagayaki, however, showed the highest productivity, and it is recommended for hydroponic cultivation. | RESUMO A relação N:K influencia o equilíbrio entre as fases vegetativa e reprodutiva, pois o potássio atua em processos que ajudam a regular o crescimento das plantas, quando a disponibilidade de nitrogênio é elevada. No entanto, há carência de informações sobre relações N:K adequadas para o cultivo do pepino em sistema hidropônico-NFT. Objetivou-se com esse trabalho avaliar diferentes relações N:K da solução nutritiva de frutificação para produção de pepino em sistema hidropônico. Os tratamentos foram dois híbridos de pepino (Natsuno Kagayaki e Runner) e quatro soluções nutritivas com diferentes relações N:K (p/p) (1:0,5; 1:1,0; 1:2,0 e 1:3,0) na fase de reprodutiva, arranjados como parcelas subdivididas, no delineamento em blocos casualizados com quatro repetições. Aos 33 dias após a semeadura (DAS) avaliou-se o índice SPAD, na quarta folha expandida, a partir do ápice da planta, o número de brotações e teve inicio as colheitas. Coletou-se a parte aérea das plantas para avaliação de massa fresca, massa seca e número de folhas por planta aos 54 DAS. Os resultados demonstraram que a maior concentração de K na solução nutritiva de frutificação não altera o comprimento dos frutos, mas aumenta o diâmetro e a produtividade. As relações de N:K na solução nutritiva de 1:2,0 e 1:3,0 (p/p) proporcionaram maiores produtividades para os híbridos estudados. Entretanto, o híbrido Natsuno Kagayaki apresentou maior produtividade, sendo o mais recomendado para o cultivo hidropônico.

The N:K ratio influences the balance between vegetative and reproductive stages, because potassium plays important roles in the processes that regulate plant growth when the nitrogen availability is high. However, there is a lack of information on the N:K ratio suitable for cucumber cultivation in an NFT-hydroponic system. The objective of this study is to evaluate the different N:K ratios in fruiting nutrient solutions for cucumber production in a hydroponic system. Treatments consisted of two cucumber hybrids (Natsuno Kagayaki and Runner) and four nutrition solutions with different N:K ratios (w/w) (1:0.5, 1:1.0, 1:2.0, and 1:3.0) in the reproductive phase arranged as split plots in a randomized block design with four replications. On the 33rd day after sowing (DAS), the SPAD index on the fourth expanded leaf from the plant apex, number of broaches, and harvests were evaluated. The aerial parts of the plants were collected on the 54th DAS for evaluation of fresh mass, dry mass, and number of leaves per plant. The results showed that the highest concentration of K in the fruiting nutrient solution does not alter the length of the fruits but increases their diameter yield. The N:K ratios in the 1:2.0 and 1:3.0 (w/w) nutrient solutions provided greater yields in both evaluated hybrids. The hybrid Natsuno Kagayaki, however, showed the highest productivity, and it is recommended for hydroponic cultivation. | A relação N:K influencia o equilíbrio entre as fases vegetativa e reprodutiva, pois o potássio atua em processos que ajudam a regular o crescimento das plantas, quando a disponibilidade de nitrogênio é elevada. No entanto, há carência de informações sobre relações N:K adequadas para o cultivo do pepino em sistema hidropônico-NFT. Objetivou-se com esse trabalho avaliar diferentes relações N:K da solução nutritiva de frutificação para produção de pepino em sistema hidropônico. Os tratamentos foram dois híbridos de pepino (Natsuno Kagayaki e Runner) e quatro soluções nutritivas com diferentes relações N:K (p/p) (1:0,5; 1:1,0; 1:2,0 e 1:3,0) na fase de reprodutiva, arranjados como parcelas subdivididas, no delineamento em blocos casualizados com quatro repetições. Aos 33 dias após a semeadura (DAS) avaliou-se o índice SPAD, na quarta folha expandida, a partir do ápice da planta, o número de brotações e teve inicio as colheitas. Coletou-se a parte aérea das plantas para avaliação de massa fresca, massa seca e número de folhas por planta aos 54 DAS. Os resultados demonstraram que a maior concentração de K na solução nutritiva de frutificação não altera o comprimento dos frutos, mas aumenta o diâmetro e a produtividade. As relações de N:K na solução nutritiva de 1:2,0 e 1:3,0 (p/p) proporcionaram maiores produtividades para os híbridos estudados. Entretanto, o híbrido Natsuno Kagayaki apresentou maior produtividade, sendo o mais recomendado para o cultivo hidropônico.

This study aimed to assess the foam-mat drying kinetics of mango pulp (cv. Keitt) adding 1% Emustab® and 1% Super Liga Neutra®, for a whipping time of 20 minutes, dried in a forced-air convection oven at different temperatures (50, 60 and 70oC) and foam layer thicknesses (0.5, 1.0 and 1.5 cm). Drying kinetic data were used to build drying curves and then fit to Page, Henderson, Henderson and Pabis, Logarithmic and two-term Exponential models. Both temperature and foam layer thickness influenced drying time, which reached the shortest value at the highest temperature and smallest thickness. The Page model provided the best fit to the experimental drying curve data.

ABSTRACT This study aimed to assess the foam-mat drying kinetics of mango pulp (cv. Keitt) adding 1% Emustab® and 1% Super Liga Neutra®, for a whipping time of 20 minutes, dried in a forced -air convection oven at different temperatures (50, 60 and 70oC) and foam layer thicknesses (0.5, 1.0 and 1.5 cm). Drying kinetic data were used to build drying curves and then fit to Page, Henderson, Henderson and Pabis, Logarithmic and two-term Exponential models. Both temperature and foam layer thickness influenced drying time, which reached the shortest value at the highest temperature and smallest thickness. The Page model provided the best fit to the experimental drying curve data. | RESUMO Este trabalho foi realizado com o objetivo de avaliar a cinética de secagem em camada de espuma da polpa de manga cv. Keitt, com a incorporação de 1% de Emustab® e 1% de Super Liga Neutra®, para um tempo de batimento de 20 min, desidratada em estufa com circulação forçada de ar em diferentes temperaturas (50; 60 e 70 oC) e espessuras de camada de espuma (0,5; 1,0 e 1,5 cm). A partir dos dados obtidos durante a cinética de secagem foram construídas as curvas de secagem e ajustados os modelos de Page, Henderson, Henderson e Pabis, Logarítmico e Exponencial de dois termos. Verificou-se que a temperatura de secagem e a espessura da camada de espuma influenciaram no tempo de secagem, com os menores tempos de secagem observados na maior temperatura e na menor espessura. O modelo de Page foi o que melhor se ajustou aos dados experimentais das curvas de secagem.

The objective of this work was to assess the pulp resistance, soluble solids and yield of watermelon fruits grown under different irrigation managements (determined by the ISAREG model) and mulches, and their interactions. After a survey carried out on local producers, two experiments were conducted, using a completely randomized block design in split - plot arrangement with four replications, in the Teaching, Research and Extension Unit (UEPE) of the Federal Institute of Ceara (IFCE), Jaguaribe - Apodi Irrigation District (DIJA), State of Ceara, Brazil. The treatments consisted of four irrigation managements in the plots, M1 (100% of the available - water capacity (AWC) of the soil), M2 (80%), M3 (60%) and M4 (average water depth used by local producers) and four mulch types in the sub - plots, without mulching (C0) with rice husk (C1), white plastic (C2) and black plastic (C3) as mulches. The results were subjected to analysis of variance, and significant results were subjected to regression (irrigation managements), average test (mulches) and trend graphs (interaction between the factors). The irrigation management practiced during the watermelon crop cycle by the local producers of the Irrigation District of Jaguaribe - Apodi (DIJA) in the State of Ceara, Brazil, is not appropriated, since they usually apply more water than the highest water depth determined by the ISAREG model (100% of the AWC). The plants grown under irrigation water depth of 365.20 mm (M1) and soils with mulches of rice husk or white plastic had the highest yields and fruits with better quality of soluble solids and pulp resistance.

RESUMO Objetivou-se avaliar a resistência de polpa e os sólidos solúveis dos frutos, e a produtividade da melancieira, sob diferentes proposições de irrigação (geradas pelo ISAREG) e condições de cobertura do solo; e seus efeitos de interação. Após pesquisa de campo junto aos irrigantes foram realizados dois experimentos na UEPE (Unidade de Ensino, Pesquisa e Extensão) do IFCE, no Distrito de irrigação Jaguaribe -Apodi, DIJA, sob delineamento em blocos completos ao acaso, com parcelas subdivididas e quatro repetições. Os tratamentos consistiram da combinação de quatro proposições de irrigação (M1 - manutenção de 100% da capacidade de água disponível no solo (CAD); M2 - 80 %; M3 - 60%; e M4 - lâmina modal dos irrigantes) nas parcelas, e quatro sub-parcelas, compostas por três condições de cobertura no solo (coberturas com casca de arroz, com “mulching” branco e com “mulching” preto, denominadas C1, C2 e C3), e uma sem cobertura, denominada C0. Os resultados foram submetidos à análise de variância e quando significativos, à regressão (lâminas), a teste de médias (coberturas) e a gráficos de tendência (interação entre os fatores). Concluiu-se que os irrigantes não praticam o manejo correto da irrigação, pois aplicam, durante todo o ciclo da melancia, mais água do que a indicação de maior lâmina do ISAREG (100% da CAD). As plantas irrigadas pela lâmina M1 em solo coberto por casca de arroz e “mulching” branco demonstraram melhores características produtivas e de pós-colheita. | ABSTRACT The objective of this work was to assess the pulp resistance, soluble solids and yield of watermelon fruits grown under different irrigation managements (determined by the ISAREG model) and mulches, and their interactions. After a survey carried out on local producers, two experiments were conducted, using a completely randomized block design in split-plot arrangement with four replications, in the Teaching, Research and Extension Unit (UEPE) of the Federal Institute of Ceara (IFCE), Jaguaribe-Apodi Irrigation District (DIJA), State of Ceara, Brazil. The treatments consisted of four irrigation managements in the plots, M1 (100% of the available-water capacity (AWC) of the soil), M2 (80%), M3 (60%) and M4 (average water depth used by local producers) and four mulch types in the sub-plots, without mulching (C0) with rice husk (C1), white plastic (C2) and black plastic (C3) as mulches. The results were subjected to analysis of variance, and significant results were subjected to regression (irrigation managements), average test (mulches) and trend graphs (interaction between the factors). The irrigation management practiced during the watermelon crop cycle by the local producers of the Irrigation District of Jaguaribe-Apodi (DIJA) in the State of Ceara, Brazil, is not appropriated, since they usually apply more water than the highest water depth determined by the ISAREG model (100% of the AWC). The plants grown under irrigation water depth of 365.20 mm (M1) and soils with mulches of rice husk or white plastic had the highest yields and fruits with better quality of soluble solids and pulp resistance.

Cowpea is broadly cultivated worldwide, especially in semi-arid or arid regions where soil or irrigation water salt contents can negatively influence the species’ productive capacity. The objective of this study was to evaluate the morphophysiological responses of cowpea genotypes to irrigation water salinity. The experiment was conducted in a greenhouse, under a completely randomized design with nine replications and in a 5x3 factorial scheme. Treatments consisted of five levels of irrigation water electrical conductivity - EC (EC0: 0.55; EC1: 1.60; EC2: 3.20; EC3: 4.80 and EC4: 6.40 dS m-1), applied from the 15th day after sowing (DAS), and three cowpea genotypes (G1: BRS Imponente; G2: MNC04-795F-168 and G3: MNC04-795F-159). EC increases at 35 DAS promoted stem diameter reductions of 8.0% (G1), 11.4% (G2), and 7.7% (G3), indicating different resistance to salinity by each genotype. Leaf area reductions at 25 and 38 DAS were 30.9% and 38.8% for EC0 and EC4, respectively. The BRS Imponente cultivar presented a performance superior to those of G2 and G3 in relation to stem diameter and stem dry matter at 25 DAS, and root-shoot and root-leaf ratios at 38 DAS.

ABSTRACT Cowpea is broadly cultivated worldwide, especially in semi-arid or arid regions where soil or irrigation water salt contents can negatively influence the species’ productive capacity. The objective of this study was to evaluate the morphophysiological responses of cowpea genotypes to irrigation water salinity. The experiment was conducted in a greenhouse, under a completely randomized design with nine replications and in a 5x3 factorial scheme. Treatments consisted of five levels of irrigation water electrical conductivity - EC (EC0: 0.55; EC1: 1.60; EC2: 3.20; EC3: 4.80 and EC4: 6.40 dS m-1), applied from the 15th day after sowing (DAS), and three cowpea genotypes (G1: BRS Imponente; G2: MNC04-795F-168 and G3: MNC04-795F-159). EC increases at 35 DAS promoted stem diameter reductions of 8.0% (G1), 11.4% (G2), and 7.7% (G3), indicating different resistance to salinity by each genotype. Leaf area reductions at 25 and 38 DAS were 30.9% and 38.8% for EC0 and EC4, respectively. The BRS Imponente cultivar presented a performance superior to those of G2 and G3 in relation to stem diameter and stem dry matter at 25 DAS, and root-shoot and root-leaf ratios at 38 DAS. | RESUMO O feijão-caupi é bastante cultivado no mundo, principalmente em regiões semiáridas ou áridas onde o teor de sais presentes no solo ou na água de irrigação pode influenciar negativamente na capacidade produtiva da espécie. Objetivou-se com o presente trabalho, avaliar as respostas morfofisiológicas de genótipos de feijão-caupi à salinidade da água de irrigação. O experimento foi conduzido em casa de vegetação no delineamento inteiramente casualizado com nove repetições, em esquema fatorial 5x3, sendo cinco níveis de condutividade elétrica da água de irrigação - CE (CE0: 0,55; CE1: 1,60; CE2: 3,20; CE3: 4,80 e CE4: 6,40 dS m-1) aplicados a partir do 15º dia após a semeadura (DAS) e três genótipos de feijão-caupi (G1: BRS Imponente; G2: MNC04-795F-168 e G3: MNC04-795F-159). Aumentos nas CE aos 35 DAS, promoveram reduções no diâmetro do caule de 8,0% (G1), 11,4% (G2) e 7,7% (G3) indicando resistências diferenciadas dos genótipos aos efeitos da salinidade. Entre CE0 e CE4 as reduções na área foliar aos 25 e 38 DAS foram de 30,9% e 38,8%, respectivamente. Os efeitos negativos da salinidade foram mais intensos nas matérias secas da raiz e da haste, aos 20 DAS e na matéria seca das folhas, aos 30 DAS. A cultivar BRS Imponente apresenta desempenho superior a G2 e G3 em relação ao diâmetro do caule e matéria seca da haste, aos 25 DAS, e razão parte aérea raiz e folha raiz, aos 38 DAS.