The objective of this study was to evaluate the effect of different doses of nitrogen (N), applied via fertirrigation, on the initial growth components of the camu-camu plants. It was conducted with the use of a randomized block experimental design with 5 treatments: 0; 40; 80; 120 and 160 kg ha-1 of N, eight replicates and seven plants per experimental parcel. The experiment lasted for a period of 270 days. The diameter of stem (mm) and the height of the plant (cm) were evaluated every 30 days and the number of branches and total length of branches (cm) were evaluated every 90 days. At the end of the experiment, chlorophyll a index, dry mass of the leaves (g), dry mass of the branches (g), dry mass of the roots (g), total dry mass (g), and the Dickson Quality Index (DQI) were evaluated. According to the results, camu-camu plants that did not receive nitrogen fertilization had a lower in...

A irrigação consome grande quantidade de água, sendo importante um adequado manejo da cultura para minimizar esse consumo, maximizando a produção. No intuito de obter informações para o manejo da irrigação, objetivou-se com o presente trabalho determinar a evapotranspiração da cultura (ETc), o coeficiente de cultivo (Kc) e a eficiência do uso de agua (EUAg) da cultura de milho, em solo com e sem cobertura, durante os diferentes estádios de desenvolvimento, utilizando lisímetros de drenagem. O experimento foi conduzido no campus Cauamé da Universidade Federal de Roraima, entre 19/04/2014 e 07/08/2014, em Boa Vista, RR. A evapotranspiração de referência (ETo) foi estimada pelo método de Penman-Monteith FAO. Os resultados da ETc do milho, durante o ciclo da cultura, em solo sem e com cobertura foram de 421,5 e 351,0 mm, respectivamente. As médias diárias de ETc foram de...

The objective of this study was to evaluate the effect of different doses of nitrogen (N), applied via fertirrigation, on the initial growth components of the camu-camu plants. It was conducted with the use of a randomized block experimental design with 5 treatments: 0; 40; 80; 120 and 160 kg ha-1 of N, eight replicates and seven plants per experimental parcel. The experiment lasted for a period of 270 days. The diameter of stem (mm) and the height of the plant (cm) were evaluated every 30 days and the number of branches and total length of branches (cm) were evaluated every 90 days. At the end of the experiment, chlorophyll a index, dry mass of the leaves (g), dry mass of the branches (g), dry mass of the roots (g), total dry mass (g), and the Dickson Quality Index (DQI) were evaluated. According to the results, camu-camu plants that did not receive nitrogen fertilization had a lower in...

In South America, o camu-camu has been domesticated, however, for its cultivation there is still little technical information to guarantee its adaptability and productivity in places with a well-defined dry season. The objective of this study was to characterize the spatial distribution of the root system and determine the effective depth (EP) of roots in camu-camu plants with and without mulch (WM) in uplands conditions. In an orchard, 3 plants with 3, 5 and 7 years each were chosen at random. Then mulch composed of grass (Trachypogon plumosus) was placed on a plant of each age in the canopy projection. After 12 months, the volume and EP of the roots in the 3-year-old plants with mulch was 200 mm3 and 0.3 m, and without mulch it was 500 mm3 and 0.48 m, respectively. In 5-year-old plants it was 4000 mm3 and 0.43 m with mulch, and without mulch it was 6000 mm3 and 0.64 m; and in plants wi...

Camu-camu is a native plant of the Peruvian Amazon. It is noted for its high concentration of ascorbic acid, however this feature varies widely from one location to another due to genetic and environmental factors. In order to determine the relationship between mineral nutrients and the concentration of ascorbic acid in camu-camu plants, a study was conducted in three camu-camu producing areas in flood-prone soils and soils on dry land conditions in the Ucayali Region. For this purpose, soil samples and camu-camu were collected. The content of following macronutrients was analyzed: nitrogen, phosphorus, potassium, calcium and magnesium; also was determined the concentration of aluminum, pH, organic matter and ascorbic acid. The results show that the camu-camu plantations located in upland soils had lower concentrations of ascorbic acid and lower natural fertility, than soils prone to flo...

Camu-camu is a native plant of the Peruvian Amazon. It is noted for its high concentration of ascorbic acid, however this feature varies widely from one location to another due to genetic and environmental factors. In order to determine the relationship between mineral nutrients and the concentration of ascorbic acid in camu- camu plants, a study was conducted in three camu-camu producing areas in flood-prone soils and soils on dry land conditions in the Ucayali Region. For this purpose, soil samples and camu-camu were collected. The content of following macronutrients was analyzed: nitrogen, phosphorus, potassium, calcium and magnesium; also was determined the concentration of aluminum, pH, organic matter and ascorbic acid. The results show that the camu-camu plantations located in upland soils had lower concentrations of ascorbic acid and lower natural fertility, than soils prone to fl...

Camu-camu is a native plant of the Peruvian Amazon. It is noted for its high concentration of ascorbic acid, however this feature varies widely from one location to another due to genetic and environmental factors. In order to determine the relationship between mineral nutrients and the concentration of ascorbic acid in camu-camu plants, a study was conducted in three camu-camu producing areas in flood-prone soils and soils on dry land conditions in the Ucayali Region. For this purpose, soil samples and camu-camu were collected. The content of following macronutrients was analyzed: nitrogen, phosphorus, potassium, calcium and magnesium; also was determined the concentration of aluminum, pH, organic matter and ascorbic acid. The results show that the camu-camu plantations located in upland soils had lower concentrations of ascorbic acid and lower natural fertility, than soils prone to flo...

Sugar apple (Annona squamosa L.) is one of the most widely grown member of the Annonaceae family in several regions, but there is still a lack of agronomic data regarding the management of its initial growth stages under Cerrado conditions. The aim of the present study was to evaluate the production of Annona squamosa L. seedlings under different environmental conditions achieved by using shade nets (E1: ChromatiNet® Silver 50%; E2: ChromatiNet® red 50%; E3: ChromatiNet® red 35%; E4: ChromatiNet® Silver 35%) in combination with four different substrates (S1: soil + sand + chicken manure; S2: soil + sand + cattle manure; S3: soil + sand + cattle manure + chicken manure; S4: soil + sand + sheep manure). An experiment was set up using a completely randomized design with treatments in a split-plot arrangement, with four replicates and ten plants per experimental unit. Seedling growth par...

Uma das tendências do mundo moderno é a orientação ao consumo de produtos naturais com alto valor nutritivo e vitamínico. O camu-camu é uma fruteira nativa da Amazônia, que chama a atenção pelo alto conteúdo de vitamina C (6,116 mg/100 g de polpa). La espécie está em processo de domesticação, pelo qual se vem desenvolvendo modelos tecnológicos para lograr seu estabelecimento em condições de terra firme. Com o objetivo de avaliar diferentes doses de potássio aplicadas via fertirrigação no desenvolvimento inicial de plantas de camu-camu, conduziu-se um experimento no centro experimental Agua Boa da Embrapa Roraima. Utilizou-se o delineamento experimental em blocos casualizados com 5 tratamentos 0; 40; 80; 120 e 160 kg ha-1 de K, aplicado em forma de KCl, seis repetições e sete plantas por parcela experimental. O experimento foi conduzido durante 270 dias após o trans...

Uma das tendências do mundo moderno é a orientação ao consumo de produtos naturais com alto valor nutritivo e vitamínico. O camu-camu é uma fruteira nativa da Amazônia, que chama a atenção pelo alto conteúdo de vitamina C (6,116 mg/100 g de polpa). La espécie está em processo de domesticação, pelo qual se vem desenvolvendo modelos tecnológicos para lograr seu estabelecimento em condições de terra firme. Com o objetivo de avaliar diferentes doses de potássio aplicadas via fertirrigação no desenvolvimento inicial de plantas de camu-camu, conduziu-se um experimento no centro experimental Agua Boa da Embrapa Roraima. Utilizou-se o delineamento experimental em blocos casualizados com 5 tratamentos 0; 40; 80; 120 e 160 kg ha-1 de K, aplicado em forma de KCl, seis repetições e sete plantas por parcela experimental. O experimento foi conduzido durante 270 dias após o trans...