Some components found in the composition of the tannery sludge are nutrients for the plants; it can be considered an alternative source of fertilization as they have favorable agronomic ...characteristics. However, it is reported in some studies that the presence of chromium and sodium in this residue causes physiological and anatomical disturbances that inhibit the development of the plants. The objective of this study was to evaluate the influence of chromium and sodium on the physiology, anatomy, and development of Conilon coffee seedlings grown on substrates produced with tannery sludge and equivalent doses of chromium and sodium. The experiment was carried out in nursery using randomized block design, containing 5 treatments and 7 repetitions. The treatments consisted of the application of a 40% tannery sludge dose and equivalent doses of chromium and sodium mixed with a conventional substrate. Notably, the presence of sodium in the substrate caused greater damage to the plants, negatively influencing the physiology, anatomy, and, consequently, development of the plants, while the presence of chromium suggests that it does not influence much the evaluated characteristics. The treatment with tannery sludge, on the other hand, despite containing the same chromium and sodium contents, revealed a more pronounced negative influence on the physiology, anatomy, and development patterns of the seedlings. This shows that sodium and chromium alone are not the only factors responsible for the lowest growth indicators studied.
The sensory profile from the Coffea canephora stands out for being denser, less sweet, presenting less acidity, and having characteristics of a marked aroma of roasted cereals. Coffee is essentially ...a terroir product, that is, directly influenced by environmental aspects, both natural and anthropic, in this sense, it has been argued that Coffea canephora is linked to the context of inferior coffees in sensory terms by the terroir conditions. This study aimed to characterize and investigate the terroir in different areas of Conilon coffee production, with the application of different fermentation methods, and to observe their possible gains and losses in the sensory quality of Coffea canephora. Cherry coffee samples were collected in six municipalities in the state of Espírito Santo, Brazil, which has an altitude variation from 376 m to 866 m. The study showed that the local characteristics of altitude and temperature directly influence the sensory quality, as well as demonstrated that natural fermentation in a specific altitude zone delivered good results, fixing the terroir factor. Finally, it was demonstrated that induced fermentation helps to improve sensory quality for higher altitude areas, indicating the possibility of reformulating the terroir of Conilon coffee production.
A wide range of soybean cultivars is available on the market and understanding the physiological response and yield of these materials is fundamental to develop new management systems. Thus, the ...objective of the present study was to assess ecophysiological parameters and yield of soybean cultivars under field conditions. The experiment was carried out on a farm located in the municipality of Açailândia, Maranhão, Brazil. Three commercial cultivars were used (SC1, SC2 and SC3), and gas exchanges, SPAD index, Fv/Fm, photosynthesis index (PI), instantaneous water use efficiency (WUE) and intrinsic instantaneous of the use of water (iWUE) were assessed during the vegetative (V5) and reproductive (R5) stages. In addition, the biomass and production components were obtained. A randomized complete block design was used, with three cultivars and six replications. SC2 obtained the best mean for the photochemical variables. SC2 was more efficient at both development stages in WUE, but the maximum iWUE values were obtained in SC3. The SC2 cultivar obtained the best responses in the main variables analyzed, resulting in a higher yield.
Due to the current water scarcity in the world, it is extremely important to improve the use of this natural and exhaustible resource in agriculture, by contributing to increase agricultural ...production and sustainability. Several models of crop growth simulation were developed to predict the edaphoclimatic effects on crop yield. These models are calibrated and validated for a given region using the data generated from field experiments. Therefore, the objective of this study was to calibrate and validate the FAO AquaCrop model for yacon (Smallanthus sonchifolius) crop in a tropical climate. The experiment was conducted in an experimental area located in the municipality of Ibatiba, state of Espírito Santo (Brazil) during the years of 2013 and 2014. The calibration was done using the Autumn planting and validation with the Winter and Spring plantings. For the statistical analysis, the coefficient of determination, Willmott concordance index, bias for the systematic error, root mean square error and the mean absolute error to test the model performance were used. In general, the FAO AquaCrop model predicted the root yield, total biomass and harvest index with acceptable accuracy, and with deviations of less than 6% for total and root biomass. Late planting of yacon showed a reduction in yield as well as total biomass.
Abstract
Photo-selective shading screens are emerging practices that aim to combine crop physical protection with different solar radiation filtration to achieve desired physiological responses. The ...objective of the present study was to evaluate the effect of photo-selective shading screens on the growth and physiology of purple lettuce for two transplanting seasons in tropical climate in Brazil. A 2 × 4 factorial arrangement was used, being considered the first factor, the transplanting season (spring and fall), and the second factor is the three 35% shading photo-selective shading screens (red, black and silver) and full sun control. The experimental design was a randomized complete block with four replications. The variables studied were: total fresh matter, total dry matter, leaf number, stem diameter, stem length, leaf area, SPAD chlorophyll index, nitrogen balance indexes, chlorophyll, flavonoids and anthocyanins. The photo-selective shading screens influenced the microclimate and the growth variables of purple lettuce, mainly when these plants were sown in the fall. Planting lettuce during spring may result in lower yields due to the higher investment of plants in secondary metabolites to defend against abiotic stress. According to the results, photo-selective shading screens are an appropriate agronomic technique to reduce phenolic compounds and improve lettuce cultivation conditions and can be implemented within protected cultivation practices to improve crop performance.
Coffee straw mineralization applied to the soil surface Haddade, H.T. Barth, G.H.S. Vieira, I.R. Bosa, P.A.V. Lo Monaco, I.R.; Meneghelli, C.M.; Berilli, S. da Silva
Emirates journal of food and agriculture,
05/2019, Letnik:
31, Številka:
5
Journal Article
Recenzirano
Odprti dostop
The potential use of coffee straw (composed of outer skin, pulp and parchment) as fertilizer for agricultural crops implies the need to know the dynamics of their decomposition and release of the ...nutrients. This is to assist the farmers in the management of these residues, especially in the best time of its application in the soil. The aim of this work was to evaluate the dynamics of organic carbon and organic nitrogen during the coffee straw mineralization process, when applied superficially to a Dystrophic Red-Yellow Latosol (LVAd). The experiment was conducted in a completely randomized design with ten treatments, related to different post-disposal periods to the soil (0, 7, 13, 20, 27, 34, 48, 69, 98, 147 days) and four replications. Soil samples were collected to quantify the easily oxidized organic carbon (OCeo) and organic nitrogen (ON) contents and their respective mineralized fractions. The evaluation of OCeo mineralization, being more stable and less sensitive to climatic variations, is the most appropriate parameter to estimate the mineralized fraction of the residue. The application of coffee straw in a LVAd during the month of August provides, after 147 days, mineralized fractions of OCeo and ON around 88% and 36%, respectively, in the climatic conditions of the mountain region of Espírito Santo state, Brazil.
Tannery sludge has great potential for use in agriculture, however it is a potentially toxic waste, and it is necessary to establish the ideal dose for each crop. The objective of this study was to ...evaluate the influence of fertilization with liquid tannery sludge on growth, chlorophyll a fluorescence and gas exchange of Pennisetum purpureum in two production cycles. A 2 × 6 + 1 split plot scheme was used, where the first factor was composed of two productive cycles, the second factor different fertilizations doses: 0, 30, 70, 110, 150, 190 t ha
−1
of liquid tannery sludge and an additional treatment with nitrogen, phosphorus and potassium control. Plant height, number of leaves and tillers, canopy and stem diameter, leaf area, dry matter, chlorophyll index (SPAD), chlorophyll a fluorescence and gas exchange were evaluated. The highest production of total dry matter was observed in the second production cycle. The range between 72-100 t ha
−1
of liquid tannery sludge showed the greatest gains in growth and production of elephant grass. At doses above 150 t ha
−1
of liquid tannery sludge, the photochemical apparatus begins to show possible damage to the photosystem II (PSII) and reductions in gas exchange.
In vegetable production, seedling propagation is one of the most important steps as it directly influences the final performance of the plants. In order for such condition, the propagation substrate ...must be in good condition. The objective of this work was to evaluate the effect of different combinations of tannery sludge and urban waste compost as substrates in comparison to the commercial substrate Maxfértil
®
on the growth and quality of eggplant seedlings. The experiment was conducted in a greenhouse using a randomized block design with eight treatments and six replications. The commercial substrate was Maxfértil
®
, a crushed pine bark, with limestone, and seven treatments with increasing proportions of tannery sludge/decreasing urban waste compost (0/100; 10/90; 30/70; 50/50; 70/30; 90/10 and 100/0 v/v). Characteristics of emergence, growth, quality and leaf nitrogen (N) content were evaluated. No difference was found in the emergence of eggplant seedlings among the different treatments used; however, the growth characteristics, quality and N content featured significant effects when the seeds were propagated in alternative substrates. Regression adjustments pointed to an optimal range of 41-49% of tannery sludge associated with urban waste compost for the evaluated characteristics. The strong correlation between SPAD and N content shows its potentiality in detecting N deficiencies in seedlings. The use of tannery sludge residues associated with urban waste compost seems to be an appropriate and sustainable practice for recycling with high agronomic potential.
In view of the need to increase genetic variability to obtain materials with a significant capacity to drought tolerance, this study conducted a cycle of a reciprocal recurrent selection of full-sib ...families of maize. To this end, 64 full-sib families of maize were evaluated in two environments according to their morpho-agronomic data in a randomized block design with two replicates. It were analyzed of Male flowering (MF); Female flowering (FF); Flowering interval (IF); days for flowering (DF); Plant height (PH); Ear height (EH); number of plants at the Stand (NPS); Number of broken plant (NBrP); Number of bedded plants (NBeP); Strawing (St); Ear length (EL); Ear diameter (ED); Ear number (EN); Prolificacy (Pr); Number of diseased ears (NDE); Number of ears attacked by pests (NEP); Ear weight (EW); Yield (YIE) and Total Chlorophyll Index (TCI). The analysis of variance was performed by the F test at 5% significance level, and also the evaluation of genetic parameters. Regarding morpho-agronomic data, the analysis of variance and the analysis of genetic parameters showed that there was no interaction genotype x environment with regard to the genetic variability among the families under study. Lastly, the final selection of the superior genotypes was made on the basis of the ranking of the 40 most productive families, from which, combined with the molecular data, the 30 most productive, most drought-tolerant, and most genetically diverse ones were selected to compose the next cycle of recurrent maize selection aiming water-stress tolerance.
RESUMO: Tendo em vista a necessidade de aumentar a variabilidade genética para obter materiais com significativa capacidade de tolerância à seca, este estudo conduziu um ciclo de seleção recorrente recíproca de famílias de irmãos completos de milho. Para tanto, 64 famílias de irmãos completos de milho foram avaliadas em dois ambientes de acordo com seus dados morfoagronômicos em um delineamento de blocos casualizados com duas repetições. Foram analisados o florescimento masculino (MF); florescimento feminino (FF); Intervalo de florescimento (IF); dias para florescimento (DF); Altura da planta (PH); Altura da espiga (EH); número de plantas na parcela (NPS); Número de planta quebrada (NBrP); Número de plantas com acamadas (NBeP); empalhamento (St); Comprimento da espiga (EL); Diâmetro da espiga (DE); Número de espigas (EN); Prolificidade (Pr); Número de espigas doentes (EQM); Número de espigas atacadas por pragas (NEP); Peso de espiga (EW); Rendimento de grãos (YIE) e Índice de clorofila total (TCI). A análise de variância foi realizada pelo teste F com nível de significância de 5% e também pela avaliação dos parâmetros genéticos. Em relação aos dados morfoagronômicos, a análise de variância e a análise dos parâmetros genéticos mostraram que não houve interação genótipo x ambiente no que diz respeito à variabilidade genética entre as famílias em estudo. Por fim, a seleção final dos genótipos superiores foi feita com base no ranking das 40 famílias mais produtivas, das quais, combinadas com os dados moleculares, foram selecionadas as 30 mais produtivas, mais tolerantes à seca e mais geneticamente diversificadas. para compor o próximo ciclo de seleção recorrente de milho visando tolerância ao estresse hídrico.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Plant resistance to drought stress is a parameter that should be studied with more emphasis in the search for higher agricultural yields. In this scenario, research within breeding programs should be ...directed toward specific mechanisms of action and important agricultural crops in worldwide agribusiness. From this perspective, this study carried out a bibliographic investigation regarding the advances in genetic improvement aimed at drought stress in crops using a hybrid model of analysis of scientific articles. The analysis employed bibliometric parameters for qualitative and quantitative discussion of scientific production and the methodological process of systematic review for the synthesis of the results obtained. The work was divided into four stages: the search for articles in databases, meta-analysis, bibliometric analysis, and systematic analysis. Scientific articles were searched for on the Scopus, Scielo, and Web of Science databases within a 20-year timeframe. Most authors and institutions were from Asian countries, demonstrating the need for global expansion of research on the subject. With regard to the co-occurrence networks between the keywords used in the search, a focus was observed on the following terms: drought resistance, drought stress; drought, and drought tolerance. Evidently, the primary mechanism of tolerance or even resistance studied in breeding programs is associated with the expression of genes and genetically modified organisms that confer resistance to plants. Also, the crops addressed in the research retrieved are highly diverse.