25 research outputs found
Crescimento E Produção De Antúrio Em Resposta A Cobertura Do Solo Com Serragem De Madeira
The objectives of the study were to analyze the effect of sawdust mulch on the: (1) soil characteristics; (2) growth and flower yield of the anthurium cv. ‘Apalai’. Assay was conducted in a totally randomized design in subdivided plots, with five treatments and eight replications. The treatment consisted of five volumes of sawdust 0, 20, 40, 60 and 80L m-2, distributed over the bed, every three months. Soil, plants and flower stalks were evaluated during two years. Soil temperature, moisture, organic matter, bulk density and water retention conditions were improved, while the leaf area of plants and the yield of flower stalks were increased when the soil were mulched with sawdust. In addition to increasing soil organic matter, however, no change occurred in the level of nutrients in plants. Sawdust also improved the dimension of flower stalks. Application of 40L m-2 of sawdust every three months is recommended. © (2016) Universidade Federal de Santa Maria. All rights reserved.46344044
Nitrogen And Potassium Fertilization In A Guava Orchard Evaluated For Five Cycles: Effects On The Plant And On Production
Guava response to fertilization can be monitored through plant tissue analysis. Correct interpretation of these results, based on standard levels, is of great importance for correct nutrient management of the crop. However, standard levels are constantly criticized for not considering interactions among elements. To improve the nutritional diagnosis of ‘Paluma’ guava (Psidium guajava L., Myrtaceae), an experiment was conducted using nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg per plant per cycle of N, with urea as a source with 45 % N), and potassium fertilization (0, 0.55, 1.1, and 2.2 kg per plant per cycle of K2O, with potassium chloride as a source with 60 % K2O) in an irrigated commercial area for five consecutive cycles, 2009 through 2012, observing the influence of fertilizers and climate and assessing yield and leaf element content, using the concept of isometric log ratios (ilr) to interpret leaf analysis results (N, P, Ca, Mg, K, and S). This paper showed that nutrient balances and nutrient concentration values can be interpreted coherently using compositional data analysis. Ranges of nutrient balances also were established for “Paluma” guava and validated through ranges grounded in nutrient contents currently used in Brazil. Nitrogen fertilization increased “Paluma” guava yield. The 0.5 kg N application rate per plant and the other studied treatments practically showed the same results, and their values were affected by pruning time as well as the nutrient balances. © 2016, Revista Brasileira de Ciencia do Solo. All rights reserved.4
Nitrogen And Potassium Fertilization In A Guava Orchard Evaluated For Five Cycles: Soil Cationic Balance
Soil fertility evaluation through soil analysis traditionally does not consider interaction among elements. To include the interaction effect in interpretation of soil analyses, an experiment was conducted to evaluate the effect of nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg N per plant per cycle) with urea (45% N) and potassium fertilization (0, 0.55, 1.1, and 2.2 kg K2O per plant per cycle) with potassium chloride (60% K2O) on soil cationic balance. The experiment was carried out in an irrigated commercial production area of ‘Paluma’ guava, for five consecutive cycles, 2009 through 2012, using the concept of isometric log ratio (ilr) to evaluate soil cationic balance through [K, Ca, Mg | H+Al], [K | Ca, Mg] and [Ca | Mg] balances. The compositional data analysis showed to be a suitable tool to interpret the soil cationic balance given that the soil cationic balances value was changed by nitrogen fertilization and potassium as well as the soil pH value and the concentration of K in the soil. The soil cationic balances also changed by the variations of in climate conditions at period of soil sample. An application rate of 0.55 kg K2O per plant per cycle was considered sufficient to keep K soil concentration above 1.6 mmolc dm-3. © 2016, Revista Brasileira de Ciencia do Solo. All rights reserved.4
Avaliação agronômica da aplicação do resíduo da indústria processadora de goiabas em pomar comercial de goiabeiras
Dada a escassez de informações na literatura e a importância do manejo adequado de resíduos orgânicos na agricultura, objetivou-se avaliar os efeitos da aplicação do resíduo da indústria processadora de goiabas em um Argissolo Vermelho-Amarelo, determinando-se as alterações provocadas na química do solo, no estado nutricional de goiabeiras e na produção de frutos. As doses de resíduo aplicadas no pomar foram estabelecidas em função dos teores de N no resíduo. O delineamento empregado foi o de blocos casualizados, com cinco tratamentos e quatro repetições, sendo as doses do resíduo (moído) de 0, 9, 18, 27 e 36 t ha-1 (peso do material seco). Foram feitas três aplicações do resíduo: em 2006, 2007 e 2008. O resíduo da indústria processadora de goiabas promoveu aumento nos teores de P no solo; as goiabeiras apresentaram aumento dos teores de N, Ca, Mg e Mn; a produção de frutos foi alterada positiva e significativamente no terceiro ano do experimento
Análise da variabilidade genética de acessos de Psidium spp. (Myrtaceae) avaliados quanto à reação a Meloidogyne enterolobii¹
Este trabalho teve por objetivo a caracterização molecular de 13 acessos de Psidium spp. (Myrtaceae) identificados previamente quanto à reação ao nematoide da goiabeira. A extração do DNA das amostras foi executada conforme o protocolo de Shillito e Saul (1988). Os marcadores moleculares do tipo fAFLP, foram obtidos utilizando-se do 'fAFLP Regular Plant Genomes Fingerprinting Kit' (Applied Biosystems do Brasil Ltda.) onde foram testadas 24 combinações seletivas de primers, das quais 18 apresentaram amplificação que gerou 272 marcadores polimórficos. Para a análise dos marcadores, foram utilizados os softwares GeneScan (ABI Prism versão 1.0) e Genotyper (ABI Prism versão 1.03), e os dados coletados foram transformados em matriz binária que foi analisada no software PAUP (Phylogenetic Analysis Using Parcimony - versão 3.01). Foram também calculados índices de distância genética intra e interespecífica entre os materiais. Verificou-se que os marcadores AFLP foram eficientes na discriminação dos acessos entre si, bem como apontou similaridade genética entre os acessos identificados como resistentes ao nematoide Meloidogyne enterolobii, característica esta passível de exploração no futuro
