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Shadowing of a bioenergetic species in soybean development: an analysis of the feasibility potential of this integration. Texto completo
2023
AVELINO, N. R. | CAMPOS, L. J. M. | AIRES, D. M. | SILVA, R. S. da | EVARISTO, A. B.
Drying of arabica coffee and its effect on the gene expression and activity of enzymes linked to seed physiological quality. Texto completo
2023
CARVALHO, M. H. de | ROSA, S. D. V. F. da | COELHO, S. V. B. | GUIMARÃES, C. C. | MARTINS, R. de S. | CLEMENTE, A. da C. S. | PAIVA, L. V.
The reduced longevity of coffee seeds has been attributed to their sensitivity to desiccation. Studies related to gene expression and enzyme activity in coffee seeds under drying are important for understanding the effects of drying on their physiological quality. The aim of this study was to investigate the molecular aspects of seeds under different drying methods and associate them with physiological quality. Coffee seeds with different water contents were dried both slowly and rapidly. Enzymatic activity was analysed, as well as the expression of genes that encode the enzymes superoxide dismutase, catalase, peroxiredoxins, isocitrate lyase, and endo-ß-mannanase. There was a significant effect of drying speed and final water content on enzyme activity and on the expression of the different genes analysed. In seeds under rapid drying, there was greater expression of the genes that encode the enzymes catalase and endo-ß-mannanase. Greater expression of the 1 CYS PRX and SOD genes and greater activity of the ICL isoenzymes were found in seeds with superior physiological quality, but greater activity of the endo-β-mannanase and CAT enzymes occurred in seeds with lower physiological quality.
Mostrar más [+] Menos [-]Selection of Theobroma grandiflorum clones adapted to agroforestry systems using an additive index. Texto completo
2023
ALVES, R. M. | CHAVES, S. F. da S.
In fruit tree breeding, selection indices are used to identify the genotypes that combine desirable commercial and non-commercial characteristics. As Theobroma grandiflorum is generally cultivated in agroforestry systems (AFS), there is a need to develop cultivars that are adapted to such environments. In this study, the objective was to select the most promising genotypes for their future use in AFS based on the additive index, a pioneering method for this crop. The trial was carried out for 12 years in an agroforestry system in the municipality of Tomé-Açu, Pará State, Brazil. The 16 evaluated clones were completely randomised with a variable number of repetitions. The average number of fruits produced as well as the morpho-agronomic characteristics of the fruits were analysed. Mixed linear models were used to estimate the components of variance and predict the genotypic values. The genetic correlation between the variables was estimated, and the selection of genotypes was based on the additive index, with a positive orientation of all variables except the thickness of the fruit shells and the weight of the fruits. Clones 42, 44, 46, 47, 57, 61, and 64 performed well for all the analysed variables, resulting in a selection gain of 7.3% and low incidence rates of witches? broom disease. These genotypes can be made available to producers in the form of clones for use in AFS and can further be included in future hybridisations in T. grandiflorum breeding.
Mostrar más [+] Menos [-]Long-term effects of cover crops on physical-hydric properties of compacted soil Texto completo
2023
Deonir Secco | Doglas Bassegio | Araceli Ciotti de Marins | Bruna de Villa | Luiz Antônio Zanão Junior | Tiago Roque Benetoli da Silva | Affonso Celso Gonçalves Junior
The screening of cover crops is essential for improving the physical-hydric properties of compacted soils. This study aimed to evaluate the effects of mixed or single cover crops on improving the physical-hydric properties of compacted Oxisol. Species with tap-rooted and fibrous-rooted rooting patterns were evaluated. The species included pearl millet (Pennisetum americanum), pigeon pea (Cajanus cajan), sunn hemp (Crotalaria spectabilis), velvet bean (Mucuna pruriens), white oat (Avena sativa), black oat (Avena strigosa), rye (Secale cereale), black oat + forage turnip (Raphanus sativus), black oat + white lupin (Lupinus albus L.), and black oat + group pea (Pisum arvense L.). Mixing cover crops did not improve the physical properties of the soil. The tap-rooted pigeon pea effectively reduces bulk density and increases porosity and saturated hydraulic conductivity (Ksat) in compact soils. The selection of cover crops with characteristics that improve soil physical-hydric properties is crucial for compacted areas.
Mostrar más [+] Menos [-]Biochar as a soil conditioner for common bean plants Texto completo
2023
William Gleidson Alves Torres | Fernando Colen | Michele Xavier Vieira Megda | Leidivan Almeida Frazão | Fabiano Barbosa de Souza Prates | Regynaldo Arruda Sampaio | Luiz Arnaldo Fernandes
Biochar is a carbon-rich material produced during organic waste pyrolysis. In this context, two experiments were performed to evaluate the effect of biochar produced from rice husks and cattle manure on soil fertility and common bean production, as well as to identify the optimal dose of cattle manure biochar to be applied. The first experiment (Experiment I) was conducted according to a completely randomized design (factorial scheme 2 × 2 × 2 + 1) with six replicates: two types of biochar (cattle manure biochar and rice husk biochar), with and without acidity correction [addition of calcium carbonate and magnesium carbonate (PA) in a proportion of 4:1 (Ca:Mg) to raise the soil base saturation to 60%], with or without the addition of 120 mg dm-3 of phosphorus (P) as ammonium phosphate, and a control treatment (without biochar, acidity correction, and P). Based on the results of Experiment I, a second experiment was conducted according to a completely randomized design, with five treatments (doses of biochar from cattle manure) and four replications. Rice husk biochar, as a conditioner of soil chemical properties, had less prominent effects than cattle manure biochar. Cattle manure biochar functioned as a corrective for soil acidity and a source of nutrients (mainly phosphorus). The dose corresponding to 5.46% of the soil volume led to the maximum grain production by common bean plants.
Mostrar más [+] Menos [-]Physical soil properties after seven years of composted tannery-sludge application Texto completo
2023
Ricardo Silva de Sousa | Luís Alfredo Pinheiro Leal Nunes | Francisco de Alcântara Neto | Henrique Antunes de Souza | Ademir Sérgio Ferreira de Araújo
This study was performed to investigate the effects of composted tannery sludge (CTS) on the physical properties of tropical sandy soil after seven years of CTS application. CTS was applied to a Fluvisol at five rates (0.0, 2.5, 5.0, 10.0, and 20.0 Mg ha-1) in experimental plots (sized 20 m2) with four replications. Water infiltration into the soil was determined in the field with the concentric-ring infiltrometer method. Bulk density, total porosity, macroporosity, and microporosity were determined in the soil samples. The permanent CTS application altered the physical properties of the soil and led to a decrease in bulk density. The total porosity, microporosity and macroporosity values in the CTS-applied soil ranged from 44.1–51.7, 34.6–39.4, and 9.1–12.8%, respectively. Water-infiltration rates were significantly influenced by CTS. The cumulative infiltrated water in the soil varied from 21.3–34.7 cm. The basic infiltration rate was lower in the unamended soil and increased with an increase in the rate of CTS application. This study confirmed that the physical soil parameters improved after the permanent CTS application. Therefore, this application may be a suitable strategy for improving physical soil properties over time.
Mostrar más [+] Menos [-]Effects of dietary palm oil on nutritional indices of Diatraea saccharalis (Lepidoptera: Crambidae) for Cotesia flavipes (Hymenoptera: Braconidae) production Texto completo
2023
Jessica Aline Soares de Abreu | Ronaldo Roberto Tait Caleffe | Alison Henrique Ferreira Julio | Stefany Rodrigues de Oliveira | Helio Conte | Maria Claudia Colla Ruvolo-Takasusuki
Cotesia flavipes parasitizes Diatraea saccharalis, a pest that causes major losses to sugarcane production. The mass production of C. flavipes and its subsequent release onto sugarcane is one form of biological control of D. saccharalis. An essential factor for successfully fighting this pest is the development of host diets that can increase the efficiency of C. flavipes production. Palm oil contains saturated fatty acids, unsaturated fatty acids, and polyunsaturated linoleic acid. However, little is known about the effects of palm oil on C. flavipes production in the laboratory. Different concentrations of palm oil were added to the D. saccharalis diet and its nutritional indices were analyzed. Subsequently, the production and sex ratio of C. flavipes were determined. Our results indicated that the addition of higher palm oil concentrations to an artificial diet generated a high relative consumption rate (RCR) in D. saccharalis, and consequently a high relative metabolic rate (RMR), which resulted in a lower production of the parasitoid. In contrast, the lowest palm oil concentration in the artificial diet generated a low RMR and resulted in high-efficiency conversion of ingested food (ECI), enabling D. saccharalis to yield more C. flavipes. This suggests that palm oil influences the quantity of D. saccharalis ingested, which determines the number of C. flavipes that will be generated. In this study, supplementation of a D. saccharalis diet with 0.25% palm oil increased the production of C. flavipes. Therefore, this level of palm oil supplementation can aid in the production of C. flavipes on a laboratory-scale. Further research, including increasing the number of parasitoids, must be performed to mass-produce the augmentative releases of C. flavipes to manage D. saccharalis.
Mostrar más [+] Menos [-]The influence of the summer pruning on ‘Fuji’ apples storage under controlled atmosphere Texto completo
2023
Adriana Lugaresi | Cristiano André Steffens | Angélica Schmitz Heinzen | Cristhian Leonardo Fenili | Alberto Fontanella Brighenti | Mariuccia Schlichting De Martin | Cassandro Vidal Talamini do Amarante
This study aimed to evaluate the effect of the summer pruning time in ‘Fuji’ apple trees on the quality of fruit at harvest and after storage in controlled atmosphere with extremely low O2 (CA-ELO) (0.5 kPa O2). The treatments evaluated were summer pruning in December, January, and February, in addition to a control treatment (without summer pruning). The experiment was carried out in the 2018/2019 and 2019/2020 growing seasons. The fruit were evaluated at harvest and after eight months of CA-ELO (0.5 kPa O2 + <0.5 kPa CO2/1.5 ± 0.2°C/92 ± 2% RH) storage, at chamber opening, and after 7 days of shelf-life at 23 ± 3°C and 60 ± 5% RH. The quality of the fruit was evaluated through of soluble solids, flesh firmness, titratable acidity, fruit color, and physiological disorder incidence (sunburn and flesh browning), in addition to enzymatic activity and concentration of functional compounds. There was no significant effect of the summer pruning time on fruit flesh firmness, soluble solids, titratable acidity, and rot incidence after storage under CA-ELO plus 7 days of shelf life. Summer pruning in February resulted in fruit with higher peel red color development, which in general contains a higher concentration of functional compounds at harvest (total phenolic compounds and total antioxidant activity), and lower flesh browning incidence in ‘Fuji’ apples stored under CA-ELO. The nitrogen (N) concentration and nitrogen/calcium ratio (N/Ca) in the second growing season were lower in fruit from plants pruned in February, compared to no summer pruning or earlier pruning. The superoxide dismutase and peroxidase enzyme activity were lower in fruit from treatments with summer pruning in January and February, whereas the polyphenol oxidase enzyme activity was lower when summer pruning was conducted in February.
Mostrar más [+] Menos [-]Biomass yield and chemical composition of the cassava plant over two vegetative growth cycles Texto completo
2023
Nathane Colombo Menegucci | Magali Leonel | Adalton Mazetti Fernandes | Jason Geter da Silva Nunes | Jesion Geibel da Silva Nunes
The objective of this work was to study the biomass production and chemical composition of the different parts of the cassava plant during the first and second vegetative cycles, with the aim of providing data that can contribute to the understanding of the response of cassava cultivars to different harvest ages. The experimental design consisted of randomized blocks in split plot scheme. Plots were represented by cultivars IAC 90 and IAC 118-95 and subplots by crop age (2, 4, 6, 8, 10, 12, 14, 16, and 18 months after planting). Our results showed that the ‘IAC 90’ allocated a higher proportion of assimilates to the leaves, stem and planted cutting than the ‘IAC 118-95’, which was more efficient in allocating dry matter to the storage roots. Storage roots showed an increase of more than 50% in starch content 14 months after planting. The cultivar IAC 118-95 is distinguished by the higher harvest index, allowing earlier harvesting, with possible valorisation of the leaves as industrial raw material. Variables showed different degrees of inter-relationships amongst themselves. Total plant fresh matter and dry matter yields were positively correlated with growth parameters and root starch for both cultivars. Harvest time and cultivar are key factors that should be considered to increase profits in the cassava agro-industrial chain.
Mostrar más [+] Menos [-]Genomic prediction using the lmekin function from the coxme R package Texto completo
2023
Clemeson Silva de Souza | Vinícius Silva dos Santos | Sebastião Martins Filho
The increasing use of genomic selection (GS) in plant and animal breeding programs has led to the development of software that fits models based on unique scenarios. Accordingly, several R packages have been developed for GS. The lmekin function from the coxme R package was one of the first functions implemented in R to fit models with random family effects using the pedigree–based relationship matrix. The function allows the user to provide the covariance structures for the random effects; thus, the GBLUP model can be fitted. This fitting process consists of replacing, in the traditional BLUP model, the additive relationship matrix derived from a pedigree by the additive relationship matrix derived from markers. Thus, the objective of this study was to employ the lmekin function in the context of genomic prediction by comparing the results of this function with those obtained using five R packages for GS: rrBLUP, BGLR, sommer, lme4qtl, and lme4GS. The comparisons were performed considering the computational times and predicted values for a wheat dataset and simulated big data. In addition, we implemented a 5-fold cross-validation scheme through considering the values predicted by the lmekin function for the wheat dataset. The results indicated that the lmekin function was effective in predicting genomic breeding values considering multiple random effects and relatively small sample sizes. The rrBLUP package processed the fastest for the scenario with only one genetic random effect, and the high temporal efficiency of the sommer package was confirmed for the scenario with more than one genetic random effect. Differences in computational times occurred because of the different algorithms implemented in the packages to estimate the variance components.
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