34 research outputs found
Growth analysis and yield of tomato crop under different irrigation depths
The influence of irrigation depth was evaluated on tomato crop hybrid Debora plus for salad in a field experiment in split-block design with five treatments (irrigation depth of 40, 60, 80, 100 and 120% of crop evapotranspiration - ETc) and four replications. During the experiment, ten plant samples were collected to determine phytomass and leaf area to estimate plant growth parameters for different depths of irrigation. Results showed maximal growth between 70 and 80 days after transplanting in all treatments. Increase in irrigation depth above 80% of ETc increased crop growth rate (CGR), leaf area index (LAI) and total production of tomato fruits, although same commercial fruit yield was obtained with the lower depths. Therefore, an increase in depth of irrigation above 80% of ETc promotes higher water and energy consumption, without providing an increase in commercial yield of tomato fruits
Lysine biosynthesis and nitrogen metabolism in quinoa (Chenopodium quinoa): Study of enzymes and nitrogen-containing compounds
Aspartate kinase (AK, EC 2.7.2.4), homoserine dehydrogenase (HSDH, EC 1.1.1.3) and dihydrodipicolinate synthase (DHDPS, EC 4.2.1.52) were isolated and partially purified from immature Chenopodium quinoa Willd seeds. Enzyme activities were studied in the presence of the aspartate-derived amino acids lysine, threonine and methionine and also the lysine analogue S-2-aminoethyl-L-cysteine (AEC), at 1 mM and 5 mM. The results confirmed the existence of, at least, two AK isoenzymes, one inhibited by lysine and the other inhibited by threonine, the latter being predominant in quinoa seeds. HSDH activity was also shown to be partially inhibited by threonine, whereas some of the activity was resistant to the inhibitory effect, indicating the presence of two isoenzymes, one resistant and another sensitive to threonine inhibition. Only one DHDPS isoenzyme highly sensitive to lysine inhibition was detected. The results suggest that the high concentration of lysine observed in quinoa seeds is possibly due to a combined effect of increased lysine, synthesis and accumulation in the soluble form and/or as protein lysine. Nitrogen assimilation was also investigated and based on nitrate content, nitrate reductase activity, amino acid distribution and ureide content, the leaves were identified as the predominant site of nitrate reduction in this plant species. The amino acid profile analysis in leaves and roots also indicated an important role of soluble glutamine as a nitrogen transporting compound. (c) 2007 Elsevier Masson SAS. All rights reserved
Production of cut sunflower under water volumes and substrates with coconut fiber
ABSTRACT This study aimed to evaluate the production of cut sunflower in response to different water volumes and substrates, composed of soil and coconut fiber. Two simultaneous experiments were conducted in greenhouse, located in the Horticulture Sector of the Federal Rural University of Rio de Janeiro (UFRRJ), SeropĂ©dica - RJ, Brazil (22Âș 48â S, 43Âș 41â W and altitude of 33 m), between April and June 2016. Water was applied by an Simplified Irrigation Controller (SIC), allowing the application of different volumes (33, 67 and 133% of retention capacity of substrate) in comparison to the control treatment (100%). The substrates used were 1/3 of coconut fiber and 2/3 of soil (v/v) (Experiment 1), and 2/3 of coconut fiber and 1/3 of soil (Experiment 2). The experimental design was completely randomized, with 5 replicates. The treatment with 100% of the volume applied by the SIC led to best growth of sunflower, increasing the potential income obtained with stems at better marketing standard according to the prices practiced
Growth, Yield and Grain Nutritional Quality in Three Brazilian Pearl Millets (Pennisetum americanum L.) with African or Indian origins
ABSTRACT In this study, we are presenting recommendations to the best agricultural use as well as for plant breeding of three millet cultivars namely ENA1 and ENA2, which have African origin, and BRS1501 originally from India. These cultivars were evaluated for growth, yield and grain quality traits. The morphological traits evaluated in this study indicated that the African genotypes ENA1 and ENA2 are better than the Indian genotype BRS1501 for no-till farming or to produce forage with 15% of crude protein at flowering and at harvest to produce stover (around 7% of crude protein content) for livestock feeding. The BRS1501 cultivar exhibited the highest values for total crude protein, albumins and prolamins, phytate and mineral contents in grains. ENA1 and ENA2 exhibited the highest values of globulin and glutelin contents. The electrophoretic patterns for storage proteins were similar across the three millets cultivars, except for a higher intensity of two glutelin bands with 21 and 24 kDa in BRS1501. Together, the results allow us to recommend BRS1501 for grain production and ENA1 and ENA2 for biomass production
Differential ultrastructural changes in tomato hormonal mutants exposed to cadmium
Cadmium (Cd) is a toxic heavy metal, which can cause severe damage to plant development. The aim of this work was to characterize ultrastructural changes induced by Cd in miniature tomato cultivar Micro-Tom (MT) mutants and their wild-type counterpart. Leaves of diageotropica (dgt) and Never ripe (Nr) tomato hormonal mutants and wild-type MT were analysed by light, scanning and transmission electron microscopy in order to characterize the structural changes caused by the exposure to 1 mM CdCl(2). The effect of Cd on leaf ultrastructure was observed most noticeably in the chloroplasts, which exhibited changes in organelle shape and internal organization, of the thylakoid membranes and stroma. Cd caused an increase in the intercellular spaces in Nr leaves, but a decrease in the intercellular spaces in dgt leaves, as well as a decrease in the size of mesophyll cells in the mutants. Roots of the tomato hormonal mutants, when analysed by light microscopy, exhibited alterations in root diameter and disintegration of the epidermis and the external layers of the cortex. A comparative analysis has allowed the identification of specific Cd-induced ultrastructural changes in wild-type tomato, the pattern of which was not always exhibited by the mutants. (C) 2009 Elsevier B.V. All rights reserved.Fundacao de Amparo Pesquisa do Estado de Sao Paulo (FAPESP)[04/08444-6]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq-Brazil
Intensive care treatments associated with favorable discharge outcomes in Argentine children with severe traumatic brain injury: For the South American Guideline Adherence Group.
Little is known about the critical care management of children with traumatic brain injury (TBI) in low middle income countries. We aimed to identify indicators of intensive care unit (ICU) treatments associated with favorable outcomes in Argentine children with severe TBI.We conducted a secondary analysis of data from patients previously enrolled in a prospective seven center study of children with severe TBI who were admitted to an ICU in one of the seven study centers. Severe TBI was defined by head AIS â„ 3, head CT with traumatic lesion, and admission GCS < 9. Seven indicators of best practice TBI care were examined. The primary outcome was discharge Pediatric Cerebral Performance Category Scale [PCPC] and Pediatric Overall Performance category Scale [POPC]. We also examined variation in ICU care and in-patient mortality.Of the 117 children, 67% were male and 7.5 (4.3) years on average, 92% had isolated TBI. Hypotension (54%) was more common than hypoxia (28%) and clinical or radiographic signs of high intracranial pressure (ICP) were observed in 92%. Yet, ICP monitoring occurred in 60% and hyperosmolar therapy was used in only 36%. Adherence to indicators of best TBI practice ranged from 55.6% to 83.7% across the seven centers and adherence was associated with favorable discharge PCPC (aRR 0.98; 95% CI [0.96, 0.99]), and POPC (aRR 0.98; 95% CI [0.96, 0.99]). Compared to patients whose adherence rates were below 65%, patients whose adherence rates were higher between 75%-100% had better discharge PCPC (aRR 0.28; 95% CI [0.10, 0.83]) and POPC (aRR 0.32; 95% CI [0.15, 0.73]. Two indicators were associated with favorable discharge PCPC: Avoidance of hypoxia (aRR 0.46; 95% CI [0.23, 0.93]), and Nutrition started in 72 hours (aRR 0.45; 95% CI [0.21, 0.99]). Avoiding hypoxia was also associated with favorable discharge POPC (aRR 0.47; 95% CI [0.22, 0.99]).There is variation in Argentine ICU practice in the care of children with severe TBI. Second insults are common and hyperosmolar therapy use is uncommon. Adherence to best practice TBI care by avoiding hypoxia and providing timely nutrition were associated with significantly favorable discharge outcomes. Implementing strategies that prevent hypoxia and facilitate early nutrition in the ICUs are urgently needed to improve pediatric TBI outcomes