A.R. Dechen

Nitrogen and Potassium Fertilization Affect Apple Fruit Quality in Southern Brazil

Abstract Nitrogen (N) and potassium (K) are usually found in higher concentrations than other macronutrients in apple (Malus x domestica Borkh) fruits and are most frequently associated with changes in fruit quality. The aim of this article was to evaluate the effects of N and K fertilization on some fruit quality attributes of Fuji apple. The experiment was conducted at São Joaquim, State of Santa Catarina, Brazil, during 2004 and 2005. A factorial design was used with N and K annual fertilizer rates (0, 50, 100, and 200 kg ha−1 of N and K2O) replicated in three orchards. Fifteen days prior to harvest, three fruit samples were collected from each treatment and site. One sample was used for total soluble solid content (TSS), titratable acidity, pulp firmness, and fruit color parameter analyses, and the other samples were refrigerated in a conventional atmosphere for 3 and 6 months for subsequent determination of fruit quality. Nitrogen fertilization negatively affected fruit color, flesh firmness, and TSS content. These same variables were positively affected by K fertilization, except for flesh firmness.

Produção de tubérculos de batata-semente em função das adubações nitrogenada, fosfatada e potássica

This work was carried out in Sao Joaquim, Santa Catarina State, Brazil, in two cultivation cycles (1999/00 and 2001/02), to evaluate the effect of the nitrogen, phosphorus and potassium fertilization on the tuber yield of potato-seed. The experiment had a randomized block design with four replicates. Three levels of N and K2O (0; 150 and 300 kg ha-1) and four rates of P2O5 (0; 350; 700 and 1050 kg ha-1) were tested. The tuber production was affected by the nitrogen and phosphorus fertilization and, depending on the cultivation cycle, also by the potassium one. The yield was increased by P2O5 rates from 694 to 920 kg ha-1 depending on the cultivation cycle and nitrogen rates. These amounts were higher than those recommended by the official institution for Santa Catarina and Rio Grande do Sul States.

DRIS Use on Apple Orchard Nutritional Evaluation in Response to Potassium Fertilization

Abstract The aim of this work was to use the diagnosis and recommendation integrated system (DRIS) method to evaluate the nutritional status of an apple orchard, cv. Gala/MM106, at Vacaria, State of Rio Grande do Sul, Brazil. Treatments consisted of four levels of annual maintenance potassium fertilization. Data on fruit production and fruit pellicle color were restored from 1995 to 2000, as well as the data on leaf macro and micro-nutrient concentrations. The DRIS indices and nutritional balance index (NBI) for each nutrient were determined using three methods: Beaufils, Jones, and Elwali and Gascho. The results showed that (i) the NBI, calculated from the generated norms, were negatively correlated negative correlated with productivity and fruit coloration, and (ii) the DRIS method, described by Elwali and Gascho and using the F value, was the most suitable for apple tree orchards, because the NBI values obtained with this method best indicated the nutritional status of the plants and provided a more accurate nutritional diagnosis.

Adubação de crescimento de macieira Cv. Catarina sobre porta-enxerto marubakaido em São Joaquim-SC

ABSTRACT - The vegetative vigor and the yield potential of the apple trees primarily depend on the initial soil fertilization (growingor plant formation fertilization), which is based mainly on nitrogen application. The “Catarina” apple cultivar selected as sca b resistant,seems to be a promising cultivar for higher altitude areas in Southern Brazil. As a new cultivar, fertilizer recommendations fo r the initialplant formation have not been available yet. For this reason, an experiment was carried out to establish the nitrogen requirement tobalance both vegetative vigor and the plant yield potential. The orchard was planted in August 1998 in a shallow soil originated fromacid magmatic rocks, in Sao Joaquim – SC, Brazil. The cultivar studied was Catarina grafted onto Marubakaido rootstock. The ar ea hadbeen limed to elevate the soil pH; phosphorous and potassium were supplied according to fertilizer recommendations. The N ratestested were: 0, 25, 50 and 100 kg ha -1 (sum of three annual applications beginning from the subsequent year to the plantation), placedon the projection of the tree canopy. Eight plants organized in randomized blocks design with eight replications formed the plots. Thebranches growth of the year and the number of spurs were not affected by any N rates. However, it was supposed that the nitrogenfertilization from previous years had affected the fruit buds nutrition, considering the significant increasing of the number o f fruits andthe yield of the trees on first year of production.Index terms : nitrogen, apple trees, young tree fertilization.

Comparison of citrus rooting evaluation methods using root images in soil profiles and root weight

Com o objetivo de comparar metodos de estudo do sistema radicular em citros, foram tomadas, em video, imagens de raizes situadas em um perfil de solo, e as mesmas raizes foram coletadas e pesadas. As raizes presentes nas imagens foram quantificadas (comprimento e area) por meio do programa SIARCS, desenvolvido pela Embrapa. A area do perfil analisada foi delimitada por aneis de ferro, que tambem foram utilizados para retirar as raizes para a determinacao do peso seco. O comprimento e a area de raizes, determinados por imagens digitalizadas, forneceram uma boa estimativa da quantidade de raizes presentes no perfil.

Carência de macronutrientes e de boro em plantas de urucu

Plantas de urucu (Bixa orellana L. var. Peruana) foram cultivadas em vasos contendo como substrato silica moida e irrigadas periodicamente com solucao completa (todos os nutrientes) e com omissao de N, P, K, Ca, Mg, S e B. Uma vez evidenciados os sintomas de desnutricao as plantas foram coletadas e divididas em folhas superiores, folhas inferiores, caule e raiz. O material seco foi analisado para os elementos em questao. Foi obtido o quadro sintomatologico das carencias e foram encontrados os seguintes niveis analiticos em folhas do tratamento completo e dos tratamentos com omissao: N% 3,04 - 1,89; P% 0,16 - 0,04; K% 2,67 - 0,15; Ca% 1,10 - 0,50; Mg% 0,28 - 0,19; S% 0,24 - 0,16; B ppm 42,00 - 19,00.

Nutrição mineral do cajueiro (Anacardium occidentale L.): I - deficiência dos macronutrientes - nota prévia

Na presente nota previa, os autores relatam as observacoes iniciais acerca da sintomatologia de carencia dos micro nutrientes, obtida em casa-de-vegetacao. Observaram que as carencias de B e Fe sao de facil identificacao ; sendo que as carencias em Cu e Zn sao complexas e de dificil obtencao. Nao conseguiram obter o quadro sintomatologico para o Mo e Mn. Os autores apresentam, em primeira aproximacao, os niveis adequados e de carencia pela analise foliar.

Influência do boro no desenvolvimento e na composição mineral do pimentão

An experiment was carried out in Piracicaba (Brazil) from February to June 1994, to study the effects of boron application on the development and mineral composition of sweet pepper (Capsicum annuum L.), cultivar Magda. The experiment was carried out in a randomized block design with four levels of borax (0; 5; 10 and 20 kg ha-1 equivalent to 0; 0.6; 1.1 and 2.2 kg ha-1 of B) and four replications. The plant height, number of leaves and flowers were evaluated, also the foliar area, dry weight of aerial part and nutrient contents in the leaves plus petioles at 45 days after transplanting date. In addition, fruit fresh weight; pericarp and seed mineral composition were evaluated 40 days after transplanting date. Different concentrations of borax did not affect the evaluated characteristics nor the macronutrient and B, Cu, Fe, Mn and Zn levels in the leaves plus petioles and fruits. For the pericarp and seeds, the concentrations of boron were higher in the seeds than of in petioles for all levels of applied borax.

Nutrição mineral do cajueiro (Anacardium occidentale L.): III - absorção de nutrientes - nota prévia

Na presente nota previa os autores apresentam os primeiros dados acerca da extracao e exportacao de nutrientes atraves do cajueiro a partir de 1 a 14 anos de idade. As plantas foram colhidas de uma plantacao localizada no Municipio de Terezinha, BA, situadas em um latossolo de baixa fertilidade, exceto em K. As plantas foram pesadas e analisadas para N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. Constataram os autores que o cajueiro cresce continuamente ate aos 14 anos. Uma arvore aos 10 anos de idade contem: N- 1,5 kg; P- 0,2 kg; K- 1,1 kg; Ca-0,2 kg;Mg-0,3 kg; S- 0,1 kg; B- 4,0 g;Cu-1,4 g;Fe- 2,0 g;Mn- 7,8 g;Zn- 2,6 g. Aquilataram os autores que a exportacao de nutrientes atraves de 1 kg de frutos e a seguinte: N- 13,9 g; P- 1,3 g; K- 6,2 g; Ca- 0,3 g; Mg- 1,3 g; S- 0,5 g; B-18,5 mg; Cu-16,2 mg; Fe- 36,9 mg; Mn-13,2 mg. Finalmente observaram que a concentracao de N, Mg, S, Cu, Fe e Zn nao varia nas folhas em funcao da idade da planta; sendo que a concentracao em P, K, Ca, B e Mn varia com a idade da planta.

Extração de macro e micronutrientes por frutos de quatro variedades de manga (Mangifera indica L.)

Quantities of nutrients removed by the harvest of mango fruits (Mangifera indica L.) of four varieties (Haden, Sensation, Tommy-Atkins and Edward) are presented. The orchard was nine years old, situated on an alfison in Piracicaba, SP, Brazil. The fruits were harvested 39, 55, 97, 108, 125 and 144 days from the initial stage of growth. The fruits were rinsed, dried, weighed, and analyzed for nutrient content by laboratory conventional methods. The authors concluded: Fruit growth followed the decreasing order: Edward, Haden, Tommy-Atkins and Sensation; The total amount of nutrients (macro and micronutrients) removed by each variety for the production of 15,000kg of fresh fruits by hectare amounted to: Haden 44kg, Sensation 29kg, Tommy-Atkins 40kg and Edward 39kg.