Aurélio Paes Barros Júnior

Cultivo da alface em túneis baixos de agrotêxtil

O experimento foi conduzido na horta da ESAM, de marco a abril de 2004, com o objetivo de avaliar o desempenho de cultivares da alface em tuneis baixos de agrotextil. O delineamento experimental utilizado foi de blocos casualizados completos em esquema fatorial 2 x 3, com quatro repeticoes. Os tratamentos foram constituidos pela combinacao de duas cultivares de alface (Taina e Baba de Verao) e tres tipos de cobertura (dois tuneis baixos de 50 cm de altura de agrotextil branco com gramatura de 13 g/m² e 40 g/m² e sem cobertura). Avaliou-se a altura e diâmetro de plantas, numero de folhas por planta, massa seca da parte aerea e produtividade. A cultivar Baba de Verao apresentou melhor desempenho em altura de plantas, numero de folhas e produtividade. O tunel baixo de agrotextil branco com gramatura de 40 g/m² promoveu maior altura, diâmetro e produtividade de alface.

Desempenho agronômico do bicultivo da alface em sistemas consorciados com cenoura em faixa sob diferentes densidades populacionais

The experiment was carried out from June to September 2003, in the field, in Mossoro, Rio Grande do Norte State, Brazil, to evaluate the lettuce bicropping agronomic performance in intercropping systems with carrot in a strip arrangement under different planting densities of component crops. The experimental design used was of randomized complete blocks in a 4x4 factorial scheme with five replications. The treatments of the factorial consisted of the combination of four lettuce-planting densities [40%, 60%, 80% and 100% of the recommended sole crop density (RSCD)] with four carrot-planting densities (40%, 60%, 80% and 100% of the RSCD). The recommended planting densities for lettuce and carrot in sole crop were of 250.000 and 500.000 plants/ha, respectively. The planted lettuce and carrot cultivars were respectively: Taina and Brasilia. Evaluations of plant height and diameter, number of leaves and fresh weight per plant, shoot dry mass, and leaf productivity were made in the lettuce crop. In the carrot crop, total and commercial yields of roots were evaluated. There was no significant interaction between lettuce densities and carrot densities in any assessed trait of both crops. In the first lettuce growing, the increase of planting density increased significantly lettuce leaf yield and decreased plant height and fresh mass per plant. Increasing in the association of planting densities of both crops increased shoot dry mass of lettuce. In the second lettuce growing, the increase of planting density increased significantly plant height, leaf productivity and shoot dry mass, besides decreasing fresh mass per plant. As the association of carrot and lettuce planting densities increased, the total and commercial yield of roots increased.

Desempenho agronômico da cenoura adubada com jitirana antes de sua semeadura

The scarlet starglory is an herbaceous plant native that is presented as a potential source for green manure in the semi-arid northeast of Brazil, and generates many benefits, especially the increased availability of nutrients for crops. The objective of this present study was to evaluate the agronomic performance of carrot fertilized with scarlet starglory before carrot sowing. An experiment was conducted at the teaching garden of the Plant Sciences Department, Universidade Federal Rural do Semi-Arido (UFERSA), Mossoro-RN, from September to December 2008. The experimental design used was a randomized complete block with treatments arranged in a 4 x 4 + 1 factorial scheme, with 3 replications. The first factor was composed of the quantities of scarlet starglory incorporated into the soil (5.4; 8.8; 12.2 and 15.6 t ha-1 on a dry basis), and the second factor by the times of scarlet starglory incorporation into the soil (0; 10; 20 and 30 days before sowing of carrot - DBS). The additional treatment (control) was fertilized with 80 t ha-1 of cattle manure. The characteristics evaluated were: plant height, leaf number per plant, dry mass of shoot, commercial productivity, scrap productivity, classified productivity. There was no significant interaction between the quantities of scarlet starglory incorporated into the soil and its times of incorporation before carrot sowing on any of those evaluated characteristics. The highest productive performance of carrot was obtained in the amount of 15.6 t ha-1 of scarlet starglory incorporated into the soil at the time of 20 days prior to the carrot planting time.

Economic analysis of cucumber and lettuce intercropping under greenhouse in the winter-spring

The economical analysis complements the evaluation of the intercrop systems efficiency, considering besides the physical production of crops, the price of products according to their quality classification and time of the year. Intercropping systems of lettuce and cucumber in two plant populations under greenhouse were economically evaluated in winter-spring, in Jaboticabal City, São Paulo State, Brazil. The total operating cost (TOC) of cucumber and lettuce as sole crop and intercropping were estimated, as well as gross revenue (GR) and operating profit (OP). The labor for the crops was the component with greater participation in the TOC of crops in intercropping and single crop. Greater GR and OP were observed in intercrops established by transplanting lettuce and cucumbers on the same day. Considering the operating profit and the land efficient ratio, it is recommended the intercropping of lettuce transplanted until 10 days after the transplanting (DAT) of cucumber with two rows per plot, and at 0 DAT of cucumber grown with a row plot.

Produção e qualidade de melão amarelo influenciado por coberturas do solo e lâminas de irrigação no período chuvoso

Growing a melon crop during the rainfall period has been a great challenge for producers from the north eastern Brazil due to crop sanitary problems. This work was aimed at evaluating the effects of soil coverages and irrigation depth on yield and quality of yellow melon (hybrid Goldex) during the rainfall period. The experiment was carried out at Fazenda Santa Julia Agro-Comercial Exportadora de Frutos Tropicais Ltda, Mossoro-RN, Northeastern Brazil, during the period of April to July 2003. The experimental design was a randomized complete blocks with four replications. The treatments were the combinations of five soil coverages (soil with no coverage and coverages with polyethylene films - black, silvery, yellow, and brown) with three irrigation depth (100%, 86% and 72% of the standard lamina, this equivalent to 238.44mm). The traits evaluated were number, mean weight and yield of marketable (internal and external markets), refuse and total fruits, pulp firmness and thickness, fruit shape index, and soluble solids content. Interaction between soil coverage types and irrigation depth was significant with regard to total fruit yield. The greatest marketable fruit yields and soluble solids contents were obtained with the use of polyethylene soil coverages. The numbers of marketable, refuse and total fruits, as well as the yields of marketable and refuse fruits were not significantly affected by the irrigation depth.

Associação de densidades populacionais de cenoura e alface no desempenho agronômico da cenoura em cultivo consorciado em faixa

An experiment was carried out from June to September 2003, in the field, in Mossoro, Rio Grande do Norte State, Brazil. Associations of carrot (cv. Brasilia) and lettuce (cv. Taina) planting densities on carrot agronomic performance in strip-intercropping system were evaluated. The experimental design was of randomized complete blocks in a 4 x 4 factorial scheme with five replications. The treatments of the factorial consisted of the combination of four carrot-planting densities [100%; 80%; 60% and 40% of the recommended sole crop density (RSCD)] with four lettuce-planting densities (100%; 80%; 60% and 40% of the RSCD). The recommended planting density for the sole crop in the region is of 500.000 plants/ha for carrot and 250.000 plants/ha for lettuce. From the carrot crop we evaluated the plant height, shoot and root dry mass, total and commercial yield and classification of roots. No significant interaction between carrot densities and lettuce densities for any assessed trait in carrot crop was obtained. Also, no significant effect of increase in lettuce density was observed for any carrot-assessed trait. Plant height increased as carrot planting density increased, whereas shoot and root dry mass, and percentage of long and mean, and refused roots decreased with increasing of carrot density. As the association of carrot and lettuce planting densities increased, the total and commercial yield and percentage of short roots increased.

Produção de beterraba fertilizada com jitirana em diferentes doses e tempos de incorporação ao solo

This study was conducted from July to November 2009, at Universidade Federal Rural do Semi-Arido (UFERSA), Mossoro, RN, Brazil, to assess the production of sugar beet (Beta vulgaris L.) fertilized with scarlet starglory (Merremia aegyptia L.) at different doses and times of soil incorporation. The experimental design was a randomized complete block with treatments arranged in a 4 x 4 + 1 factorial, with three replicates and 72 plants per plot, where the first factor consisted of the doses of scarlet starglory (5.4, 8.8, 12.2 and 15. 6 t ha-1 on dry basis), the second one by the times of soil incorporation (0, 10, 20, and 30 days after sowing - DAS), and additional treatment with 80 t ha-1 of cattle manure. The sugar beet cultivar grown was Early Wonder. The best productive performance for sugar beet was obtained in the dose of 15.6 t ha-1 of scarlet starglory incorporated into the soil at time 0 day. Economic indicators in the dose of scarlet starglory of 15.6 t ha-1 at time 0 day of its incorporation into the soil were higher than those obtained with the use of 80 t ha-1 of cattle manure. The cultivation of sugar beet is agro-economically viable with the use of scarlet starglory as green manure.

Qualidade de raízes de cenoura em sistemas consorciados com alface sob diferentes densidades populacionais

The experiment was carried out from June to September 2003, in Mossoro, Rio Grande do Norte State, Brazil, to evaluate the quality of carrot roots (cv. Brasilia) in intercropped systems with lettuce (cv. Taina) under different planting densities. The experimental design used was of randomized blocks in a 4 x 4 factorial scheme with three replications. The treatments consisted of the combination of four carrot-planting densities [(40%, 60%, 80% and 100% of the recommended sole crop density (RSCD)] with four lettuce-planting densities (40%, 60%, 80% and 100% of RSCD). The evaluated quality characteristics of the carrot roots were: titrable total acidity (TTA), total soluble solids (TSS), total sugars (TSU), pH, and TSS/TSS ratio, besides commercial productivity of carrot roots and lettuce yield. There was a significant interaction between carrot planting-densities and lettuce-planting densities on TSS of carrot roots. The TTS content and pH increased with increasing carrot-planting densities. Commercial productivity of carrot roots and lettuce yield also increased with increasing in planting densities. The variation in the carrot planting density did not influence lettuce yield but the variation in the lettuce planting density negatively influenced commercial productivity of carrot roots. Among the assessed characteristics, TSS and TSS were significantly correlated with commercial productivity, showing that these traits may be representative of carrot root quality.

Cristalização de melão pelo processo lento de açucaramento

The experiment was carried out in the Food Technology Laboratory of the Escola Superior de Agricultura de Mossoro (ESAM), Mossoro-RN, Brazil to evaluate the possibility of processing the melon pulp as a crystallized fruit by using the us following melon varieties: Galia, Pele de Sapo, and Orange Flesh, utilizing the slow sugary process. The pulps were withdrawn in little ball form and put successively into sucrose solutions at 20, 30, 40, 50, 60 and 70°Brix, until boiling, keeping them in inactivity for 24 hours in each solution. After that, the fruits were placed in a stove at 50°C during 6 hours, reaching final humidity between 26.16 and 27.53%. Evaluations for humidity content, pH and total soluble solids were made. In addition a sensorial analysis was made. It was observed that the melon crystallization was technically feasible. Pele de Sapo melon was the best in comparison to the other types. Changing in the melon pulp colouring was not observed.

Desempenho agroeconômico da cenoura adubada com jitirana (Merremia aegyptia)

The use of spontaneous plants of the Caatinga biome as green manure is becoming a viable option for vegetable production in northeastern Brazil. Among these plants, the scarlet starglory is a spontaneous plant adapted to the climatic and soil conditions of the region, with high biomass production, rapid growth and low C/N ratio. We evaluated the agroeconomic performance of carrot (cv. Brasilia) depending on added amounts of scarlet starglory under the ground and of its moment of incorporation. The study was carried out in a rural area, in Mossoro, Rio Grande do Norte state, Brazil, from September to December 2009. The experimental design was randomized complete blocks with the treatments arranged in a factorial scheme (4x4) + 1, with three replications. The first factor was comprised of amounts of scarlet starglory placed between the carrot rows, in a depth of 15 cm (5.4, 8.8, 12.2 and 15.6 t ha-1 on a dry basis) and the second factor, of the incorporation moment of this material (0, 15, 30 and 45 days after sowing carrots). The additional treatment (control) was 40 t ha-1 of cattle manure applied 10 days before sowing. We evaluated the marketable and total yield of roots, percentage of the different classes of roots and the economic indicators of gross income, net income, rate of return and profit margin. No significant interaction between the amounts of scarlet starglory under the soil and the incorporation moment was determined in any of the characteristics examined for carrot. The best agroeconomic performance of carrot cropping was obtained by adding 15.6 t ha-1 of scarlet starglory to the soil. The optimization of this performance was achieved with the incorporation moment of 26 days after carrot sowing.