Agrometeorological modelling of irrigated rice yield in Rio Grande do Sul, Brazil

O objetivo deste trabalho foi elaborar e testar modelos para a estimativa de rendimento de arroz irrigado, no Estado do Rio Grande do Sul. O estudo foi realizado com dados meteorológicos de temperatura mínima do ar, radiação solar global e dados de estatísticas agrícolas de rendimento de arroz irrigado, das seis regiões orizícolas do Rio Grande do Sul, referentes às safras 1982/1983 até 2005/2006. Foram feitas análises de tendência tecnológica dos rendimentos, e foram estabelecidos os indicadores agrometeorológicos para o ajuste de modelos de estimativa de rendimento de arroz irrigado, para o Rio Grande do Sul. Existe tendência tecnológica de aumento nos rendimentos de arroz irrigado no Estado. As variáveis meteorológicas avaliadas – dias com temperatura mínima do ar inferior a 15°C e radiação solar global – podem ser usadas como indicadores do rendimento de arroz irrigado. Os modelos agrometeorológicos elaborados para as seis regiões orizícolas e para o Estado do Rio Grande do Sul apresentam características de precisão, fácil implementação e baixo custo e podem, portanto, ser introduzidos ao programa nacional de previsão de safras.The objective of this work was to elaborate and test models to estimate the irrigated rice yield, in Rio Grande do Sul State, Brazil. The study was carried out using meteorological data of minimum air temperature, global solar radiation and data of agricultural statistics about the irrigated rice yield, involving six rice production regions of Rio Grande do Sul, relative to crop years from 1982/1983 to 2005/2006. Analyses of yield technological tendencies were performed, and agrometeorological indicators for model adjustments of irrigated rice yields were established. There is a technological tendency of increasing the irrigated rice yield in the State. The analyzed meteorological variables – global solar radiation and days with minimum air temperature below or equal to 15°C – can be used as indicators of the irrigated rice yield. The adjusted agrometeorological models, elaborated for the six rice production regions and for the Rio Grande do Sul State, show characteristics of accuracy, easy implementation and low cost, which make them able to be introduced in the national program of crop forecast

Agrometeorological modelling of irrigated rice yield in Rio Grande do Sul, Brazil

O objetivo deste trabalho foi elaborar e testar modelos para a estimativa de rendimento de arroz irrigado, no Estado do Rio Grande do Sul. O estudo foi realizado com dados meteorológicos de temperatura mínima do ar, radiação solar global e dados de estatísticas agrícolas de rendimento de arroz irrigado, das seis regiões orizícolas do Rio Grande do Sul, referentes às safras 1982/1983 até 2005/2006. Foram feitas análises de tendência tecnológica dos rendimentos, e foram estabelecidos os indicadores agrometeorológicos para o ajuste de modelos de estimativa de rendimento de arroz irrigado, para o Rio Grande do Sul. Existe tendência tecnológica de aumento nos rendimentos de arroz irrigado no Estado. As variáveis meteorológicas avaliadas – dias com temperatura mínima do ar inferior a 15°C e radiação solar global – podem ser usadas como indicadores do rendimento de arroz irrigado. Os modelos agrometeorológicos elaborados para as seis regiões orizícolas e para o Estado do Rio Grande do Sul apresentam características de precisão, fácil implementação e baixo custo e podem, portanto, ser introduzidos ao programa nacional de previsão de safras.The objective of this work was to elaborate and test models to estimate the irrigated rice yield, in Rio Grande do Sul State, Brazil. The study was carried out using meteorological data of minimum air temperature, global solar radiation and data of agricultural statistics about the irrigated rice yield, involving six rice production regions of Rio Grande do Sul, relative to crop years from 1982/1983 to 2005/2006. Analyses of yield technological tendencies were performed, and agrometeorological indicators for model adjustments of irrigated rice yields were established. There is a technological tendency of increasing the irrigated rice yield in the State. The analyzed meteorological variables – global solar radiation and days with minimum air temperature below or equal to 15°C – can be used as indicators of the irrigated rice yield. The adjusted agrometeorological models, elaborated for the six rice production regions and for the Rio Grande do Sul State, show characteristics of accuracy, easy implementation and low cost, which make them able to be introduced in the national program of crop forecast

Case-history: acromegalia evoluta spontaneamente in empty sella con comorbilità attive

L’acromegalia è una patologia rara caratterizzata dalla presenza di un’ipersecrezione di GH, a sua volta sostenuta, nella quasi totalità dei casi, da un adenoma ipofisario. Oltre a esporre il paziente a importanti alterazioni somatiche, essa determina anche la comparsa di complicanze cardiovascolari, metaboliche, osteoarticolari e neoplastiche, riducendo la qualità e l’aspettativa di vita. Tra queste, le più significative sono la cardiomiopatia, osservabile in una percentuale di soggetti che arriva fino al 90% nei casi di lunga durata1, le apnee ostruttive notturne che interessano fino al 70% dei pazienti alla diagnosi, l’ipertensione e il diabete rilevabili, rispettivamente, in circa il 40% e il 30% dei casi2,3. L’ipertensione, come la maggior parte delle forme secondarie, è resistente alla terapia e può essere difficilmente controllabile anche ricorrendo a farmaci appartenenti a più classi terapeutiche. In aggiunta, il rialzo pressorio può risultare severo in una percentuale di casi che arriva fino al 60%4. Uno dei principali meccanismi implicati nella sua patogenesi potrebbe essere legato alle presenza di una sindrome delle apnee ostruttive notturne (OSAS)5. In ogni caso, la prevalenza di complicanze nella popolazione acromegalica è estremamente variabile e influenzata da diversi parametri, quali l’età alla diagnosi, la durata di malattia ecc

STOMATAL CONDUCTANCE AND TRANSPIRATION IN Allium sativum L. UNDER WATER DEFICIENCY

The study aimed to verify the water stress indicators of garlic (Allium sativum L.) submitted to water deficit levels, simulating the effects of possible climatic changes. Considering that A. sativum is a crop known worldwide for its medicinal, culinary properties and applications in the ecological management of agricultural pests and, knowing that the planet is undergoing constant climatic changes, this study becomes essential to understand the influence of these changes on this species cultivation. The treatments were established with water conditions of 100, 75, 50, and 25% of the pot capacity (PC). According to the pot capacity, three bulbils were planted per pot (5 L) containing Plantmax® substrate, irrigated every two days. During the first and last week of the greenhouse treatments, the chlorophyll index was evaluated using a porometer with a seven-day interval between the analysis. The first analysis was performed in the first week of water stress and the last one in the last days of stress. Garlic plants showed sensitivity to water deficit, resulting in less conductance and transpiration in treatments 50% and 75% of water deficit, still without causing production changes. Given this study results, it is concludedThe study aimed to verify the water stress indicators of garlic (Allium sativum L.) submitted to water deficit levels, simulating the effects of possible climatic changes. Considering that A. sativum is a crop known worldwide for its medicinal, culinary properties and applications in the ecological management of agricultural pests and, knowing that the planet is undergoing constant climatic changes, this study becomes essential to understand the influence of these changes on this species cultivation. The treatments were established with water conditions of 100, 75, 50, and 25% of the pot capacity (PC). According to the pot capacity, three bulbils were planted per pot (5 L) containing Plantmax® substrate, irrigated every two days. During the first and last week of the greenhouse treatments, the chlorophyll index was evaluated using a porometer with a seven-day interval between the analysis. The first analysis was performed in the first week of water stress and the last one in the last days of stress. Garlic plants showed sensitivity to water deficit, resulting in lower conductance and transpiration compared to treatments 50% and 75% water deficit, apparently without causing changes in production. In view of the results of this study, it is concluded that Allium sativum L. will not be totally harmed by the climate changes expected in the future according to atmospheric changes in the region of Laranjeiras do Sul

Nutritional disorder in Pfaffia glomerata by mercury excess in nutrient solution

ABSTRACT:The mineral nutritional homeostasis in response to different concentrations of Hg (0, 25 and 50μM) was evaluated in Pfaffia glomerata plant. The exposure to the highest level of Hg (50µM) caused a decreasing in shoot and root fresh weights of 15.5% and 20%, respectively. Both shoot and root Hg concentrations increased linearly with increasing external Hg concentrations. Ca concentration decreased in shoot only at 50µM Hg, whereas shoot K and Mg concentrations decreased at both 25 and 50µM Hg, when compared to the control. A significant decrease in Cu, Zn, Fe and Mn concentrations in plants exposed to Hg was observed, but most Zn, Mn, and Cu in the roots. On the other hand, P concentration increased in both root and shoot of plants exposed at 25 and 50µM Hg, whereas Na concentration increased only in the root at 25 and 50µM Hg exposure. In general, tissue nutrient concentrations in P. glomerata plantlets exposed to Hg were significantly decreased, which indicates that the Hg may cause alteration on the mineral nutritional homeostasis of this species

Presence of multiple acid phosphatases activity in seedlings of cucumber, radish and rocket salad Presença de atividade de múltiplas fosfatases ácidas em plântulas de pepino, rabanete e rúcula

Acid phosphatases (3.1.3.2) are a group of enzymes widely distributed in nature, which catalyze the hydrolysis of a variety of phosphate esters in the pH range of 4-6. We confirmed the presence of acid phosphatases in seedlings of cucumber (Cucumis sativus), radish (Raphanus sativus) and rocket salad (Eruca vesicaria) under different assay conditions using a rapid and simple preparation. The results showed that the optimum pH and temperature used for all species were close to 5.5 and 35°C, respectively. The enzyme was inhibited by molybdate, fluoride, azide, levamisole, orthovanadate, Zn2+ and Cu2+. Suramin had no effect on enzyme activity. The acid phosphatase from cucumber, radish and rocket salad hydrolyzed a wide variety of phosphate esters and the highest activity was observed with PPi, ATP and GTP. These results demonstrate that the enzyme investigated in this study is different from well known ester phosphate cleaving plant enzymes (apyrase and inorganic pyrophosphatases) and this preparation could be a useful tool to future toxicological studies and to study initially all isoforms of acid phosphatase.As fosfatases ácidas (3.1.3.2) são um grupo de enzimas amplamente distribuídas na natureza, as quais catalisam a hidrólise de uma variedade de ésteres de fosfato com uma variação de pH entre quatro e seis. Foi confirmada a presença de fosfatases ácidas em plântulas de pepino (Cucumis sativus), rabanete (Raphanus sativus) e rúcula (Eruca vesicaria) sob diferentes condições de ensaio usando uma preparação rápida e simples. Os resultados mostraram que o pH e a temperatura ótimos para todas as espécies foram 5,5 e 35°C, respectivamente. A enzima foi inibida por molibdato, fluoreto, azida, levamisole, ortovanadato, Zn2+ e Cu2+. O inibidor suramim não afetou a atividade enzimática. As fosfatases ácidas de pepino, rabanete e rúcula hidrolisaram uma ampla variedade de ésteres de fosfato e a maior atividade foi observada com PPi, ATP e GTP para pepino e rabanete e PPi, frutose-6-fosfato e GTP para rúcula. Esses resultados demonstraram que a enzima investigada neste estudo é diferente das conhecidas enzimas de plantas que clivam ésteres de fosfato (apirase e pirofosfatases inorgânicas). Desse modo, esta preparação pode ser uma ferramenta útil para futuros estudos toxicológicos e para se estudar inicialmente todas as isoformas das fosfatases ácidas