Decomposition and nutrient release of leguminous green manure species in the Jaguaribe-Apodi region... Ciência Rural, v.46, n.6, jun, 2016. 970Decomposition and nutrient release of leguminous green manure species in the Jaguaribe-Apodi region, Ceará, Brazil

Propolis is a balsamic product obtained from vegetable resins by exotic Africanized bees Apis mellifera L., transported and processed by them, originating from the activity that explores and maintains these individuals. Because of its vegetable and natural origins, propolis is a complex mixture of different compound classes; among them are the volatile compounds present in the aroma. In this sense, in the present study we evaluated the volatile fraction of propolis present in the aroma obtained by distillation and simultaneous extraction, and its chemical composition was determined using coupled gas chromatography, mass spectrometry, and flame ionization detection. The majority of compounds were sesquiterpene and hydrocarbons, comprising 8.2–22.19% α-copaene and 6.2–21.7% β-caryophyllene, with additional compounds identified in greater concentrations. Multivariate analysis showed that samples collected from one region may have different chemical compositions, which may be related to the location of the resin’s production. This may be related to other bee products.

Effects of doses and phosphorus application forms were studied on the postharvest quality in seedless watermelon hybrid 'Style'. For this, an experiment was conducted in Upanema/RN, Brazil, during the period of September to December 2013, in a randomized block at factorial scheme 5×2 constituting of five phosphorus doses applied in foundation (0, 76, 168, 275 and 397 kg ha -1 of P 2 O 5 ) and foundation + fertigation (0+50, 26+50, 118+50, 225+50, 347+50 kg ha -1 of P 2 O 5 ) with four replications. Fruit harvested at commercial maturity (78 days after sowing) were evaluated by average fruit weight (AFW), pulp firmness (PF), chroma index, hue angle, soluble solids content (SS), titratable acidity (TA), maturation index (MI), total phenols content (TP), vitamin C (VC), total sugars content (TS), reducing sugars content (RS) and pH. Among the quality parameters evaluated phosphorus application forms did not affect physical characteristics of fruit, but combination of application via foundation + fertigation increased VC, TS and MI. There was interactive effect of dose and phosphorus application form for the SS, TA, pH and TP. The dose of 50 kg P 2 O 5 ha -1 applied only in fertigation significantly increased values of SS, TA and TP. It is concluded that low doses of P in cultivation and its application via foundation and fertigation improved the main quality characteristics of 'Style' watermelon.

No abstract

<p>The ability of leguminous green manure to incorporate significant amounts of nutrientes into the soil makes them excellent alternatives for the region agriculture systems. This study aimed to evaluate the potential use of six leguminous species (<em>Crotalaria juncea,</em> <em>Canavalia ensiformes,</em> <em>Cajanus cajan, Crotalaria spectabilis, Dolichos lab lab</em> and  <em>Mucuna deeringiana</em>) as green manure in an area of the Jaguaribe-Apodi agricultural region, CE, Brazil. The experiments were carried out under field conditions in a randomized block design with five replications. Sampling of biomass of shoots was carried out 78 days after sowing on each plot. It was determined the total biomass and nutrients accumulation in the plants that grew in the plots (leguminous and weeds). We concluded that the use of <em>Crotalaria juncea</em> showed up as the most promising treatment in terms of biomass production and nutrient accumulation.</p><p align="center"><em>Biomassa e acúmulo de nutrients por espécies de leguminosas utilizadas como adubo verde na região do Jaguaribe-Apodi, Ceará, Brasil<strong></strong></em></p><p><strong>Resumo</strong><strong>: </strong>A habilidade de espécies de leguminosas utilizadas como adubos verdes em incorporar quantidades significativas de nutrientes no solo fazem destas excelentes alternativas para as regiões agrícolas. O objetivo deste trabalho foi avaliar o potencial de utilização de seis espécies leguminosas (<em>Crotalaria juncea</em>; <em>Canavalia ensiformes</em> - feijão-de-porco; <em>Cajanus cajan</em> - Guandu anão; <em>Crotalaria spectabilis</em>; <em>Dolichos lab lab</em> - Labe-labe; e <em>Mucuna deeringiana</em> - Mucuna anã) como adubo verde em uma área no Agropólo Jaguaribe-Apodi, CE, Brasil. Os experimentos foram desenvolvidos em condições de campo, em blocos casualizados com cinco repetições. Foram amostradas as partes aéreas das plantas aos 78 dias após a semeadura em cada parcela. Foram determinadas a biomassa e o acúmulo totais de nutrientes das plantas que cresceram na parcela (leguminosas e invasoras). Nas condições edafoclimáticas em que o trabalho foi realizado pode-se concluir que o tratamento com utilização de <em>Crotalaria juncea</em> apresentou-se como o mais promissor em termos de aporte de fitomassa e acúmulo de nutrientes.</p>

Resumo: Para o sucesso do diagnóstico nutricional é interessante que a avaliação nutricional das plantas seja fundamentada em dados locais e como alternativa tem sido utilizado o Sistema Integrado de Diagnose e Recomendação (DRIS). Objetivou-se com este trabalho estabelecer normas DRIS preliminares para a cultura da banana na região do Baixo Jaguaribe, CE, com base em banco de dados com resultados de análise foliar. Foram geradas normas DRIS para a região do Baixo Jaguaribe a partir de 171 resultados de análises foliares relativas aos distritos de irrigação Jaguaribe-Apodi (DIJA) e Tabuleiro de Russas (DISTAR), de um total de 487. Os valores de referência foram obtidos através da relação dual entre os nutrientes transformadas por logaritmo neperiano, sendo calculadas as suas respectivas médias e desvios padrões. A partir dos índices DRIS obtidos foram determinadas as frequências de resultados com quadro de deficiência e de excesso de cada nutriente. As normas DRIS, específicas para cada local, mostraram diferenças quando comparadas com as geradas com a totalidade dos dados. Os diagnósticos gerados com as normas específicas coincidiram em menos de 60% quando comparados com os obtidos por normas de referência da literatura. As normas DRIS obtidas necessitam ser validadas a partir de dados de produção comercial, bem como de ensaios de adubação.Palavras-chave: Diagnose nutricional. Musa sp. Nutrição mineral. Abstract:For the success of nutritional diagnosis, it is important that the nutritional evaluation of a plant be based on local data, with the Diagnosis and Recommendation Integrated System (DRIS) being used as an alternative. The objective of this study was to establish preliminary DRIS norms for banana crops in the region of the Lower Jaguaribe, in the state of Ceará (CE), using a database of the results of foliar analysis. A total of 487 DRIS norms were generated for the region of the Lower Jaguaribe from 171 results of foliar analysis relating to the irrigation districts of Jaguaribe-Apodi (DIJA) and Tabuleiro de Russas (DISTAR). Reference values were obtained from the dual relationship between nutrients, transformed by natural logarithm, and their mean values and standard deviations calculated. The frequency of results for a deficiency or excess of each nutrient was determined from the DRIS indices obtained. The specific DRIS norms for each site showed differences when compared to those generated from all the data. The diagnoses generated by the specific norms agreed by less than 60% in comparison to those obtained using reference norms from the literature. The DRIS norms obtained need to be validated using data from commercial production, as well as from fertilizer trials.Key words: Nutritional diagnosis. Musa sp. Mineral nutrition.Obtenção de normas DRIS preliminares e faixas de suficiência para bananeira do subgrupo prata na região do Baixo Jaguaribe, CE, BrasilObtaining preliminary DRIS norms and sufficiency ranges in banana of the prata subgroup, in the region of the Lower Jaguaribe, Ceará, Brazil

Studies on nutrient uptake are important to understand nutritional needs of crops, which demand may also be influenced by fertilization management, particularly P fertilization. Thus, the aim of this study was to evaluate macronutrient accumulation and distribution in watermelon cv. Magnum, under two forms of phosphate fertilization. The experiment was carried out in a sandy-textured Argisol in Mossoró-RN. The experimental design was a randomized block design, arranged in split plot in time, with four replicates. We evaluated dose of 137 kg ha-1 of P2O5 under two forms of fertilization [pre-planting (F0) and pre-planting + topdressing (F1)]. Triple superphosphate (SFT) was used for pre-planting applications and topdressing applications were done through fertigation using monoammonium phosphate (MAP, 34 kg ha-1 of P2O5). Shoot samples (stem + leaf + fruit) of the experimental plots were collected at 27, 34, 40 and 55 days after emergence (DAE), and quantitative values of the accumulated nutrients were determined. In general, the highest accumulation of macronutrients occurred in the last third of the crop cycle. General accumulation of macronutrient was altered by fertilization form. An increase in P accumulation was observed using F1 fertilization, both in total and in fruits. Macronutrient accumulation rates increased during the evaluation period, except for Ca and Mg in F1 fertilization. F1 fertilization provided higher total accumulations of Ca and Mg, but the same did not occur for the accumulation in fruits.

-The objective of the present research is to characterize the phytotoxic activity of geopropolis from the Jandaira bee (Melipona subnitida Ducke) in the state of Ceará in Northeast Brazil and to analyze its effects. Extracts were prepared in 80% v/v grain alcohol at 0.25, 0.5, 0.75, and 1.0%. Their effects were determined on seed germination, radicle elongation, and hypocotyl growth of the pasture weeds malícia (Mimosa pudica) and mata-pasto (Senna obtusifolia). Extract phytotoxicity varied as functions of plant species, application dosage, and plant organ. M. pudica was more sensitive to the inhibitory effects of geopropolis than S. obtusifolia. There was a phytotoxic effect of 50% (PE50) for S. obtusifolia in terms of seed germination and in rootlet development near the maximum applied concentrations. M. pudica had PE50 and PE90 at the minimum concentration (0.25%) and near the maximum (1.00%), respectively. Thus, geopropolis extracts from the Jandaira bee (M. subnitida) are potentially phytotoxic to certain plant species.Keywords: Allelopathy. Wild bee propolis. Weed plants. Semiarid. Indigenous bees. POTENCIAL FITÓXICO DE EXTRATOS DO GEOPROPOLIS DA ABELHA JANDAIRA (M. subnitida) EM PLANTAS DANINHASRESUMO -Este trabalho teve por objetivo caracterizar a atividade fitotóxica da geoprópolis de abelhas jandaira (Melipona subnitida Ducke), nativas do estado do Ceará, e analisar, comparativamente, seus efeitos. Os extratos obtidos com álcool cereal foram preparados em concentrações de 0,25, 0,5, 0,75 e 1,0%, tendo como eluente o etanol 80%, e testados sobre a germinação de sementes, alongamento da radícula e do hipocótilo das plantas daninhas de área de pastagens cultivadas, malícia (Mimosa pudica) e mata-pasto (Senna obtusifolia). Os extratos testados evidenciaram atividade fitotóxica em intensidades que variaram em função da planta receptora, concentração, e da parte da planta analisada. A espécie M. pudica apresentou maior sensibilidade aos efeitos inibitórios do que S. obtusifolia. A espécie S. obtusifolia, quando analisada isoladamente, apresentou Efeito Fitotóxico EF50 na germinação das sementes e no desenvolvimento da radícula em concentrações próximas à máxima utilizada, enquanto que a espécie M. pudica apresentou EF50 e EF90 nas concentrações mínimas e próximas à máxima, 0,25% e 1,00%. Os extratos da geoprópolis da abelha jandaira (M. subnitida) avaliados possuem em sua composição bioativos com potencial efeito fitotóxico às plantas daninhas estudadas.Palavras-Chave: Alelopatia. Própolis de abelhas nativas. Plantas daninhas. Semiárido. Abelhas indígenas.