Carlos Alberto Barbosa Medeiros

Produção de sementes pré-básicas de batata em sistemas hidropônicos

The reduced tuber multiplication rate determines the low efficiency in the conventional methods of potato pre-basic seed production. New methods of seed production, with higher multiplication rates, may contribute to improve yield by increasing the availability of good quality seeds. This study describes two hydroponic systems, suitable for growing potato pre-basic seeds, which may represent an important step in the production process of potato seeds.

Technical and Economic Analysis of Aeroponics and other Systems for Potato Mini-Tuber Production in Latin America

Producing large quantities of high quality mini-tubers at low cost is essential for an economically viable supply of seed potatoes. Here we systematize the technical and economic aspects of aeroponics and provide a benchmark comparison of this technology with other mini-tuber production systems as developed in Latin America: conventional, semi-hydroponics, and fiber-cement tiles technology. Research methodologies included: 3-year registration of cash flows and production registers of aeroponics, economic and technical surveys, in-depth inquiry with managers of technologies. Results show that aeroponics as promoted by the International Potato Center (CIP) has several advantages, including high multiplication rates (up to 1:45), high production efficiency per area (> 900 mini-tubers per m2), savings in water, chemicals and/or energy, and positive economic indicators. The fiber-cement tiles technology from Brazil is also shown to be highly efficient and slightly more robust compared to aeroponics. Preconditions for the successful adoption of the different technologies in developing countries are discussed.ResumenLa producción de grandes cantidades de mini-tubérculos de alta calidad y a bajo precio es esencial para un abastecimiento económicamente viable de semilla de papa. Aquí sistematizamos aspectos técnicos y económicos de aeroponía y se compara la línea de base de esta tecnología con otros sistemas de producción de mini-tubérculos que han sido desarrollados en América Latina: tecnología convencional, semi-hidroponía, tejas de fibrocemento. Metodologías de investigación incluyeron: registro de flujo de caja y registro de producción de aeroponía durante 3 años, encuestas económicas y técnicas, indagación en detalle con gerentes de tecnologías. Los resultados demuestran que la aeroponía tal como lo promueve el Centro Internacional de la Papa (CIP) tiene múltiples ventajas, entre ellas tasas altas de multiplicación (hasta 1:45), eficiencia alta de producción por área (> 900 mini-tubérculos por m2), ahorros en agua, químicos y/o energía, y indicadores económicos positivos. También se demuestra que la tecnología de tejas de fibrocemento de Brasil es muy eficiente y ligeramente más robusta comparada con aeroponía. Se discuten las condiciones previas para una adopción exitosa de las diferentes tecnologías en países en vía de desarrollo.

Crescimento e produtividade de cultivares de morangueiro de "dia neutro" em diferentes densidades de plantio em sistema de cultivo orgânico

ABSTRACT GROWTH AND YIELD OF “DAY-NEUTRAL” STRAWBERRY CULTIVARS IN DIFFERENT PLANT DENSITIES IN ORGANIC CROP SYSTEMThe aim of this work was to evaluate the effect of plant density on growth and yield of two “day-neutral” strawberry cultivars in organic crop system. The experiment was carried out in Pelotas, Rio Grande do Sul State. The treatments were composed by the combination of two experimental factors: plant density (3.51; 5.26 and 7.02 plants m -2 , corresponding to double, triple and quadruple rows, respectively) and cultivars (Diamante and Aromas). The experimental design was in randomized blocks with four replications. At the end of the experiment, dry mass production and partitioning, yield and the main growth index were evaluated. The strawberry crop at 5.26 plants m -2 (triple row) provide an appropriate plant biomass production and partitioning and a yield of 30.4 Mg ha -1 . This yield was higher than the yield obtained at 3.51 plants m -2 (double row) and similar to the values found in the treatment with 7.02 plants m

BRS Ana: cultivar de batata de duplo propósito

The genotype BRS Ana is a new potato cultivar adequate for French fries, with potential for processing into frozen French fries and flakes, released in 2007. It was developed by the Embrapa Potato Breeding Program (Embrapa Temperate Agriculture, Pelotas-RS; Embrapa Transference of Technology, Office of Canoinhas-SC; and Embrapa Vegetables, Brasilia-DF), based on tuber appearance and yield, specific gravity and French fries quality. Tubers are red-skinned, lightly rough, oval shaped with shallow eyes. The pulp is white. Cultivar BRS Ana has high yield potential. In the subtropical ecosystem, cultivar BRS Ana showed higher yield (31.2 t ha-1) than the most used cultivars in Brazil when grown in autumn, and did not differ from them in the spring. In the tropical ecosystem, under irrigation, BRS Ana did not differ from both control cultivars. It produced higher percentage of marketable tubers (55.6%) and average tuber weight (108.4 g) than the controls in the fall crop of subtropical ecosystem. In both ecosystems, cultivar BRS Ana presented high specific gravity (1.086) and dry matter content (19.7%). The sensorial analysis showed that cultivar BRS Ana is adequate for home made French fries as well as for industrial processing. It is moderately susceptible to late blight (Phytophthora infestans) and presents good resistance to early blight (Alternaria solani). The reaction to the tuber soft rot (Pectobacterium sp.) is similar to the most used cultivars. It has low seed degeneration conferred by moderate resistance to PVY and low incidence of PLRV. Susceptibility to tuber physiological disorders has not been observed. It seems that BRS Ana has lower fertilizer and water requirements than the most planted cultivars, meaning reduction of crop cost and risk. In the subtropical ecosystem, tuberization starts later in spring, therefore BRS Ana should be planted earlier in the season.

Interação dos fungos micorrízicos arbusculares Glomus etunicatum e Gigaspora margarita e o nematóide das galhas Meloidogyne javanica em tomateiro

A produtividade do tomateiro pode ser severamente reduzida pelo parasitismo dos nematoides das galhas, amplamente distribuidos nas areas de producao horticola. Em condicoes de casa de vegetacao, avaliou-se o efeito da interacao entre duas especies de fungos micorrizicos arbusculares (MA), Glomus etunicatum e Gigaspora margarita e o nematoide das galhas, Meloidogyne javanica, sobre o crescimento e nutricao do tomateiro (Lycopersicon esculentum) cv. Floradade. A infeccao por M. javanica reduziu a massa de materia seca da parte aerea das plantas inoculadas. A reducao foi menos acentuada em plantas colonizadas com G. etunicatum (12%), comparadas as plantas colonizadas com G. margarita (32%) e testemunha (24%). Plantas colonizadas com G. etunicatum apresentaram maior massa de materia seca e numero de frutos comparadas aos demais tratamentos. A producao de frutos foi menos afetada pelo nematoide nas plantas inoculadas com G. etunicatum. A concentracao e o conteudo de P na parte aerea nao foram alterados pelo nematoide nas plantas colonizadas por G. etunicatum, mas foram reduzidos nas plantas colonizadas com G. margarita e testemunhas. O numero de ovos e juvenis de segundo estadio de M. javanica foi maior nas plantas colonizadas por fungos MA, comparadas as nao micorrizadas. A maior tolerância observada nas plantas colonizadas com G. etunicatum ao nematoide das galhas, possivelmente esta associada a maior estabilidade na absorcao de P.

Waste composting and proving fish for production the organic fertilizers

Resumo Os volumes de residuos gerados na atividade pesqueira sao cada vez maiores em virtude do aumento da demanda por esses produtos. Isto implica na necessidade de medidas rapidas de transformacao e ciclagens desses materiais. Dessa forma, objetivou-se avaliar o uso dos residuos gerados na atividade pesqueira como fonte de adubos orgânicos em sistemas de producao agricola familiar de base ecologica. O experimento foi realizado, na Estacao Experimental Cascata/Embrapa Clima Temperado, foi avaliado todo processo de compostagem e o de fermentacao dos residuos de peixe, identi?cando os principais pontos que viabilizam o uso desses adubos em sistemas de producao de base ecologica. O processo de compostagem da casca de arroz revelou-se incompleto durante o periodo de realizacao do experimento. O composto elaborado com residuos de pescado e casca esgotada de acacia apresenta-se como uma boa fonte de nutrientes para as culturas, podendo ser indicado como adubo orgânico para sistemas de producao de base ecologica. Em relacao ao fertilizante orgânico liquido, nas condicoes em que o experimento foi realizado, conclui-se que o composto resultante da fermentacao aerobica ou anaerobica do residuo de pescado, apresenta-se como uma viavel fonte de nutrientes para sistemas produtivos de base ecologica. Entretanto, estudos complementares necessitam ser conduzidos, para melhor entendimento e quali?cacao de ambos os processos. Palavras-chave : Reutilizacao, reciclagem, agroecologia

Production of Pre-Basic Potato Seed by Polyvinyl Chloride - PVC - Articulate Gutters Hydroponic System

The development of more efficient and productive systems for pre-basic seed potato production would improve the quality of the propagative material used by the potato growers, directly affecting the crop yields. A two-year experiment was carried out to evaluate the potato pre-basic seed production by two types of hydroponic systems (fibrocement tiles and articulated PVC gutters), two cultivars (`Baronesa` and `Eliza`) and two types of propagative material (plants coming from in vitro culture and minitubers). The PVC gutters system was highly efficient. When using minitubers, this system reached multiplication rates up to 74 tubers per plant. Minitubers were more productive than in vitro plants, independent of cultivar and hydroponic system utilized.