Sempre-vivas: recomenda??es para a sustentabilidade social e ambiental para a sedinha ou capim dourado em Minas Gerais

Colaboradores: Claudenir F?vero, Elaine Cristina Cabrini, Fernanda Testa Monteiro, M?rio Kiichiro Tanaka, Yedda SoaresConselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq

Development of everlasting flowers (Comanthera elegans (Bong.) L.R. Parra & Giul.) in three cultivation systems

Marketing the inflorescences of Comanthera elegans (Bong.) L.R. Parra & Giul. represents a source of income to many families from extractives communities in the portion of the Espinhaço Range located in the state of Minas Gerais, Brazil. Cultivating this species stands out by allying income generation with conservation since the species is currently endangered. This study aimed to assess aspects of the development of C. elegans in three cultivation systems: beds, rows, and whole area. Sowing took place in January 2009 and the inflorescences were harvested in May 2010, which characterized the experimental period. Emergence; plant density; rates of flowering, mortality, resprouting, and recruiting of new individuals; and production of inflorescences per plant and per area were assessed. Emergence began approximately 50 days after sowing. Plant density ranged from 130 to 350 plants.m-2 among the three cultivation systems. The highest mortality rate (18%) was observed at the peak of the dry season (August) and the overall mortality rate over one reproductive cycle was 49%. Of the plants that lost the aerial part, 36% resprouted. Sprouting and seed germination accounted for 30 and 3% of the recruiting of new individuals, respectively. C. elegans had two bloom (AprilMay 2009 and April-May 2010): 5.4% of the plants bloomed in the first season and 78%, in the second. Each plant produced between three and 178 inflorescences and the highest inflorescence production in terms of weight (232 g.m-2) and number (2,910 inflorescences.m-2) was observed in the cultivation in beds at 1,624 kg.ha-1

Maturity stage of fruits and factors related to nutritive and texture characters of pequi (Caryocar brasiliense Camb.) pulp

O experimento foi conduzido com o objetivo de obter informa??es sobre a influ?ncia do est?dio de desenvolvimento do fruto (?poca de coleta) e do tipo de congelamento sobre os componentes nutricionais e de textura da polpa de pequi (Caryocar brasiliense Camb.). Os frutos foram coletados na ?rvore, antes da queda natural; no ch?o, ap?s a queda natural, e ap?s a queda natural, mantidos tr?s dias em condi??o ambiente. Em cada ?poca de coleta, ap?s a retirada da casca dos frutos, um grupo de putamens foi congelado diretamente em freezer, e outro, congelado em nitrog?nio l?quido, antes do congelamento em freezer. Ap?s seis meses, foi retirada a polpa dos putamens para a an?lise dos teores de caroten?ides totais, ? -caroteno, licopeno, vitamina A, prote?nas e lip?dios; teor de celulose, hemicelulose, pectinas total, c?lcio ligado ? parede celular e total, atividade da pectinametilesterase e poligalacturonase. Os resultados indicaram que os teores de pigmentos, lip?dios, prote?nas e atividade da PG aumentaram com o avan?o do est?dio de matura??o dos frutos. Por outro lado, houve diminui??o no teor da celulose com avan?o do est?dio de matura??o, enquanto os teores de hemicelulose e c?lcio n?o foram influenciados pela idade do fruto. O tipo de congelamento interferiu nos teores de pigmentos, maiores na polpa congelada em nitrog?nio l?quido, e na atividade da PG, maior na polpa congelada apenas em freezer. Por ?ltimo, os resultados mostraram que os frutos coletados na ?rvore s?o nutricionalmente inferiores aos coletados ap?s a queda natural.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)The experiment was carried out with the purpose to obtain information about changes in the constituents responsible for nutritive and texture traits of pequi pulp related with harvest time and types of freezing. Fruits were collected in the tree before natural fall, in the ground after natural fall and in the ground three days after natural fall. In each harvest time, while one batch of the putamens was frozen in liquid nitrogen and afterwards stored in a freezer, another batch was frozen directly in the freezer. After six months the following analyses were performed in the pulp: contents of proteins, total carotenoid, b-carotene, licopene, vitamin A and lipids (nutritive characters); content of cellulose, hemicelluloses, total pectin, total and bound calcium, activity of polygalacturonase (PG) and pectinmethilesterase (PME) of the cell wall. The contents of pigments, lipids, proteins and activity of PG were the highest in the most advanced stages of maturation of fruits. On the other hand the content of cellulose decreased with the advanced stages of maturation whiles the content of hemicelluloses, total and bound calcium were not affected at the stages of maturation of the fruits. The types of freezing affected the contents of pigments; higher in the pulp frozen in liquid nitrogen; and the activity of PG was higher in the pulp frozen directly in the freezer. The fruits collected in the tree showed the lowest eating quality as judged by their lowest contents of pigments, protein and lipids. The results indicate that the most appropriate harvest time to higher quality of pequi fruits is after natural fall

Components of the xylem sap involved in the signalling root- shoot in the tomato subjected to water deficit

Plantas de tomate foram cultivadas em solução nutritiva, em casa-de- vegetação, e depois transferidas para sala-de-crescimento (fotoperíodo de 14 horas (iniciando-se às 8:00 horas), densidade de fluxo fotossintético de 500 μmol m -2 s -1 , temperatura entre 20-23°C e umidade relativa do ar entre 60-63%), com a finalidade de determinar e avaliar a ação de sinalizadores, presentes na seiva do xilema de plantas submetidas a estresse hídrico, sobre a taxa transpiratória. Os estudos foram realizados em plantas inteiras e em folhas destacadas. Em plantas, sem estresse, foram determinadas as alterações diurnas e sazonais de nutrientes e pH da seiva xilemática. Em plantas submetidas a estresse hídrico rápido (horas após adição de PEG) e lento (dias após adição de PEG), induzidos mediante adição de PEG 6000 à solução nutritiva, avaliou-se a relação entre a transpiração, potencial hídrico foliar, concentração de ácido abscísico (ABA), Ca +2 , K + , Mg +2 , NH 4+ , NO 3- , PO 4-3 e SO 4- e pH da seiva xilemática. Foi avaliada também a sensibilidade estomática ao ABA contido na seiva xilemática, em função da variação dos níveis de NO 3- , Ca +2 e PO 4+3 da seiva de plantas submetidas a estresses. Em folhas destacadas de plantas não estressadas avaliou-se o efeito da fusicocina, cloreto de lantânio e vermelho de rutênio, em combinação com ABA exógeno, sobre a taxa transpiratória. Avaliou-se também a sensibilidade estomática ao ABA exógeno, em função dos níveis de NO 3- , Ca +2 e PO 4+3 . Além disso, avaliou-se o efeito de diferentes pHs (5,5, 6,5 e 7,5), de diferentes soluçõesde imersão (seiva natural, seiva artificial e solução nutritiva de Hoagland 1⁄2 força) e aminoácidos concentrações (ácido de aspártico ácidos e orgânicos glutâmico, (málico, asparagina, maleico e cítrico), glutamina e prolina), açúcares-álcoois (manitol e sorbitol) e putrescina, sobre a taxa transpiratória. O pH da seiva xilemática variou de 5,4 a 6,6. Os pHs menos ácidos ocorreram nos meses de temperaturas médias do ar mais elevadas. A variação diurna do pH da seiva dependeu da época do ano. Exceto NO 3- e PO 4+3 , cujas concentrações na seiva do xilema foram maiores nos meses de temperaturas médias mais baixas, as concentrações dos demais nutrientes analisados não apresentaram um padrão relacionado com a época do ano. A concentração de ABA e Ca +2 , K + , Mg +2 , NH 4+ , NO 3- , PO 4-3 e SO 4- na seiva das plantas submetidas aos estresses lento e rápido aumentou com a progressão dos estresses. Nas plantas submetidas a estresses rápido ocorreu um aumento de 0,7 unidade no pH da seiva xilemática. A adição de cloreto de lantânio e vermelho de rutênio à seiva artificial inibiu a redução da taxa transpiratória promovida por ABA. Fusicocina promoveu uma redução de 30% na taxa transpiratória e inibiu os efeitos do ABA sobre a mesma. A redução na taxa transpiratória, promovida por ABA exógeno, variou com o pH e com os níveis de Ca +2 e NO 3- da solução de imersão e foi maior em folhas imersas em solução com pH 7,0, contendo NO 3- e Ca +2 . Os ácidos málico e cítrico, quando adicionados à seiva natural com pH 7,0, retardaram as reduções nas taxas transpiratórias. Dentre os aminoácidos, o ácido glutâmico promoveu reduções na taxa transpiratória. Os resultados mostraram que as interações entre os componentes da seiva xilemática envolvidos na sinalização variaram com a forma do estresse. É possível que, em tomateiro, o cálcio e a H + -ATPase estejam envolvidos na rota de transdução da sinalização do estresse hídrico, uma vez que tanto os inibidores de canais de cálcio quanto o ativador da H + -ATPase inibiram os efeitos do ABA sobre a taxa transpiratória.To determine the action of xylem sap signaling compounds on the transpiratory rate, tomato plants were subjected to water stress induced by polyethylene glycol 6000 (PEG). Before stress, plants were cultivated in nutritive solution, under glasshouse conditions, and then transferred to a growth room (photoperiod of 14 hours, beginning at the 8:00 hours), photosynthetic photon flux density of 500 μmol m -2 s -1 , 20-23oC temperature and 60-63% relative humidity. The studies were accomplished in whole plants and in detached leaves. Plants were submitted to fast (hours after addition of PEG) and slow (days after addition of PEG) water stress. It was evaluated the relationship between transpiration and leaf water potential, concentration of abscisic acid (ABA), Ca +2 , K + , Mg +2 , NH 4+ , NO 3- , PO 4-3 and SO 4- and pH of the xylem sap. It was also evaluated the stomata sensibility to ABA contained in the xylem sap, in function of the variation of the levels of NO 3- , Ca +2 and PO 4+3 . In detached leaves of non-stressed plants, it was evaluated the effects of the fusicoccina, lanthanum chloride and ruthenium red, in combination with endogenous ABA, on the transpiratory rate. It was also evaluated the effects of different pH (5,5, 6,5 and 7,5), immersion solutions (nutrient solution 1/2 force, natural sap and artificial sap), concentrations of the organic acids malic, maleic and citric, the amino acids proline, asparagine, glutamine, aspartic acid and glutamic acid, the sugar-alcohols mannitol and sorbitol and the polyamine putrescine on transpiration. It was also evaluated the effects of the addition of those products to the natural sap pH 6,0 and 7,0 on the transpiratory rate. In plants, without stress, it was observed diurnal and seasonal alterations in pH and in nutrients of xylem sap. The pHs with values above 6 was observed on January and February, months of larger medium temperature. Starting from April the pH values were inferior to 6,0, reaching the smallest values, among 5,4-5,6, on June to September, months of smaller medium temperature. Except PO4-3, whose concentration in the sap stayed constant in the period, the other ions appeared in larger concentrations in the saps collected in April - June. K+ was the cation found in larger concentration in the sap (8-16 mM), representing 50-75% of the total concentration of all the analyzed cations. Its concentration reduced in 50% from 9:00 to 16:00 hours. NH 4+ NO 3- and PO 4-3 concentrations, increased during the day, while the concentrations of SO 4 - , Ca +2 and Mg +2 didn't vary. Under growth chamber it was observed reduction on stomatal conductance while transpiration remained constant. The transpiratory rate decreased as the pH became more alkaline, independent of the immersion solution or the addition of any composed to the solution. The acids maleic and citric just promoted small reductions in the transpiratory rate when added to the artificial sap. When added to the natural sap pH 6,0, which not corresponds to thepH of the sap of stressed plants, none of the acids promoted any alteration in the transpiratory rate. In pH 7, that it corresponds to the pH of the sap of stressed plants, the addition of the malic and citric acids to the sap delayed the reductions in the transpiratory rate. The results showed that the interactions among the components of the xylem sap involved in the signaling they varied with the form of the stress. It is possible that, in tomato, the calcium and H + -ATPase are involved in the route of transduction of the signaling of the water stress, once so much the inhibitors of channels of calcium as the activator of H + -ATPase inhibited the effects of ABA on the transpiratory rate.Conselho Nacional de Desenvolvimento Científico e Tecnológic

Post-harvest quality of pequi (Caryocar brasiliense CAMB.) collected from the plant or after naturally falling off and subjected to slow and quick freezing

Soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, moisture, soluble sugars (SSU), total reducing sugars (RSU), and non-reducing sugars (NRS) were assessed in the pulp of pequi fruits collected at three ripening stages: from the plant, from the ground after naturally falling off, and collected from the ground three days after naturally falling off. The evaluation was performed after six months of freezer storage both for fruits subjected to quick freezing (liquid nitrogen followed by freezer) and slow freezing (straight into the freezer). The variables assessed were not influenced by the freezing method. The SS, TA, and RSU contents increased with the ripening stage, suggesting that the fruits collected from the plant are still immature and have lower quality than those collected after naturally falling off. Although considered mature when they fall off, fruits consumed three days after naturally falling off have better quality.Foram avaliados os teores de sólidos solúveis (SS), acidez titulável (AT), relação SS/AT, pH, teor de umidade, açúcares solúveis (AS), açúcares redutores (AR) e açúcares não redutores (ANR) em polpa de frutos de pequi coletados na planta, coletados no chão após a queda natural e coletados no chão três dias após a queda natural (caracterizando três estágios de maturação), e mantidos por seis meses em freezer após submetidos a congelamento rápido (nitrogênio líquido seguido de freezer) e lento (diretamente em freezer). As variáveis avaliadas não foram influenciadas pelo método de congelamento. Os teores de SS, AT, e AR foram crescentes com o avanço no estágio de maturação dos frutos, indicando que frutos coletados na planta encontram-se imaturos e apresentam qualidade inferior aos coletados após a queda natural. Embora considerados maduros quando caem da planta, um intervalo de três dias entre a coleta após a queda natural e o consumo favorece a qualidade dos frutos

POST-HARVEST QUALITY OF PEQUI (Caryocar brasiliense CAMB.) COLLECTED FROM THE PLANT OR AFTER NATURALLY FALLING OFF AND SUBJECTED TO SLOW AND QUICK FREEZING

ABSTRACT Soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, moisture, soluble sugars (SSU), total reducing sugars (RSU), and non-reducing sugars (NRS) were assessed in the pulp of pequi fruits collected at three ripening stages: from the plant, from the ground after naturally falling off, and collected from the ground three days after naturally falling off. The evaluation was performed after six months of freezer storage both for fruits subjected to quick freezing (liquid nitrogen followed by freezer) and slow freezing (straight into the freezer). The variables assessed were not influenced by the freezing method. The SS, TA, and RSU contents increased with the ripening stage, suggesting that the fruits collected from the plant are still immature and have lower quality than those collected after naturally falling off. Although considered mature when they fall off, fruits consumed three days after naturally falling off have better quality