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This study synthesizes magnetic iron oxide nanoparticles from agro-waste sweet pepper extract, exploring their potential as antioxidant additives and in food preservation. Iron (III) chloride hexahydrate is the precursor, with sweet pepper extract as both a reducing and capping agent at pH 7.5. Characterization techniques, including microscopy and spectroscopy, analyze the sweet pepper extract-magnetic iron oxide nanoparticles. Antioxidant capacities against 2,2-diphenyl-1-picrylhydrazyl are assessed, incorporating nanoparticles into banana-based bioplastic for grape preservation. Microscopy reveals cubic and quasi-spherical structures, and spectroscopy confirms functional groups, including Fe-O bonds. X-ray diffraction identifies cubic and monoclinic magnetite with a monoclinic hematite presence. Sweet pepper extract exhibits 100% inhibitory activity in 20 min, while sweet pepper extract-magnetic iron oxide nanoparticles show an IC50 of 128.1 µg/mL. Furthermore, these nanoparticles, stabilized with banana-based bioplastic, effectively preserve grapes, resulting in a 27.4% lower weight loss rate after 144 h compared to the control group (34.6%). This pioneering study encourages institutional research into the natural antioxidant properties of agro-waste sweet pepper combined with magnetic iron and other metal oxide nanoparticles, offering sustainable solutions for nanopackaging and food preservation. Current research focuses on refining experimental parameters and investigating diverse applications for sweet pepper extract-magnetic iron oxide nanoparticles in varied contexts.
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Sweet peppers are consumed worldwide, and traditional uses have sparked interest in their applications as dietary antioxidants, which can be enhanced in plants using elicitors. These are endowed with phytochemicals with potential health benefits such as antioxidants, bioavailability, and bioaccessibility. The trend in metabolomics shows us chemical fingerprints linking metabolomics, innovative analytical form, and bioinformatics tools. The objective was to evaluate the impact of multiple stress interactions, elicitor concentrations, and electrical conductivity on the concentration of secondary metabolites to relate their response to metabolic pathways through the foliar application of a cocktail of said elicitors in pepper crops under greenhouse conditions. The extracts were analyzed by spectrophotometry and gas chromatography, and it was shown that the PCA analysis identified phenolic compounds and low molecular weight metabolites, confirming this as a metabolomic fingerprint in the hierarchical analysis. These compounds were also integrated by simultaneous gene and metabolite simulants to obtain effect information on different metabolic pathways. Showing changes in metabolite levels at T6 (36 mM H2O2 and 3.6 dS/m) and T7 (0.1 mM SA and 3.6 dS/m) but showing statistically significant changes at T5 (3.6 dS/m) and T8 (0.1 mM SA, 36 mM H2O2, and 3.6 dS/m) compared to T1 (32 dS/m) or control. Six pathways changed significantly (p < 0.05) in stress-induced treatments: aminoacyl t-RNA and valine-leucine-isoleucine biosynthesis, and alanine-aspartate-glutamate metabolism, glycoxylate-dicarboxylate cycle, arginine-proline, and citrate. This research provided a complete profile for the characterization of metabolomic fingerprint of bell pepper under multiple stress conditions.
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Antioxidantes , Capsicum , Antioxidantes/farmacología , Antioxidantes/metabolismo , Capsicum/metabolismo , Peróxido de Hidrógeno/metabolismo , Cromatografía de Gases , Metabolómica/métodos , EspectrofotometríaRESUMEN
Seaweed extracts (SWEs) are becoming integrated into crop production systems due to their multiple beneficial effects including growth promotion and induction of defence mechanisms. However, the comprehensive molecular mechanisms of these effects are yet to be elucidated. The current study investigated the transcriptomic changes induced by SWEs derived from Sargassum vulgare and Acanthophora spicifera on tomato and sweet pepper plants. Tomato and sweet pepper plants were subjected to foliar treatment with alkaline extracts prepared from the above seaweeds. Transcriptome changes in the plants were assessed 72 h after treatments using RNA sequencing. The treated plants were also analysed for defence enzyme activities, nutrient composition and phytohormonal profiles. The results showed the significant enrichment of genes associated with several growth and defence processes including photosynthesis, carbon and nitrogen metabolism, plant hormone signal transduction, plant-pathogen interaction, secondary metabolite metabolism, MAPK signalling and amino acid biosynthesis. Activities of defence enzymes were also significantly increased in SWE-treated plants. Plant nutrient profiling showed significant increases in calcium, potassium, nitrogen, sulphur, boron, copper, iron, manganese, zinc and phosphorous levels in SWE-treated plants. Furthermore, the levels of auxins, cytokinins and gibberellins were also significantly increased in the treated plants. The severity of bacterial leaf spot and early blight incidence in plants treated with SWE was significantly reduced, in addition to other effects like an increase in chlorophyll content, plant growth, and fruit yield. The results demonstrated the complex effect of S. vulgare and A. spicifera extracts on the plants' transcriptome and provided evidence of a strong role of these extracts in increasing plant growth responses while priming the plants against pathogenic attack simultaneously. The current study contributes to the understanding of the molecular mechanisms of SWEs in plants and helps their usage as a viable organic input for sustainable crop production.
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Predator diversity in a system can have different results on the biological control of pests. Positive results can arise if natural enemies have niche complementarity, whereas negative effects can occur when one enemy interferes with heterospecifics-e.g., via intraguild predation-resulting in weaker pest suppression. Nevertheless, a coexistence is possible if enemies use the resource differentially leading to resource partitioning, and/or if the intraguild prey has some competitive advantage over the intraguild predator-i.e., is better at exploiting the shared resource or exhibits avoidance behavior. In this study, we conducted a series of field-sampling and semifield experiments to elucidate the spatiotemporal association patterns of the coccinellids Eriopis connexa (Germar) and Cycloneda sanguinea L. (Coleoptera: Coccinellidae) and determine how the trophic interactions between them could affect the biological control of aphids. We found that both coccinellid species coexist in sweet-pepper crops over time, and this coexistence could be explained by a temporal niche complementarity. Despite cooccurring spatially, they were segregated at the leaf level, which segregation can be explained by an avoidance behavior to prevent negative trophic interactions, such as cannibalism and intraguild predation. Under semifield conditions, the possible negative trophic interactions did not affect the control of aphids when both species were present, but the density of C. sanguinea was reduced at the end of the experiment. These results suggest that biological control strategies that include both species would be positive for the control of aphids on the basis of these considerations.
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Áfidos , Escarabajos , Animales , Canibalismo , Productos Agrícolas , Conducta PredatoriaRESUMEN
One of the principal etiological agents associated with losses in horticultural crops is the fungus Colletotrichum sp. This study aimed to evaluate the in vitro effectiveness of the essential oil (EO) from Cymbopogon citratus in chitosan supports for the control of Colletotrichum gloeosporioides isolated from sweet pepper plants. METHODS: The extraction and phytochemical analysis of the EO of C. citratus were performed along with its encapsulation in chitosan-agar in order to compare it with other techniques and determine its effect on C. gloeosporioides. RESULTS: The EO from the citral chemotype (58%) encapsulated in the chitosan-agar, with an 83% encapsulation efficiency in mass percentage, resulted in the total inhibition of mycelial growth at a minimum inhibitory concentration of 1370 ppm. This concentration was effective in controlling the disease under greenhouse conditions. The effectivity of the capsules containing EO was superior to that of other controls using EO evaluated in vitro. The capsules demonstrated an effective period of 51 days, with an additional 30 days of effectiveness after a reinfection cycle, thus providing similar results to the control with Trichoderma sp. CONCLUSIONS: Chitosan capsules present a promising strategy in the use of C. citratus EO on C. gloeosporioides, and they are highly effective and stable under in vitro and field conditions.
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Capsicum/microbiología , Quitosano/química , Colletotrichum/efectos de los fármacos , Colletotrichum/aislamiento & purificación , Cymbopogon/química , Aceites Volátiles/farmacología , Agar/química , Antifúngicos/farmacología , Cápsulas , Colletotrichum/patogenicidad , ADN Intergénico/genética , Pruebas de Sensibilidad Microbiana , Virulencia/efectos de los fármacosRESUMEN
Since the early 1990s, and almost simultaneously, unknown diseases started to be observed in many crops, especially in tropical and subtropical regions. These diseases were predominantly caused by begomoviruses, which were poorly known at that time. Their vector, the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), often reached unprecedented huge populations in agricultural areas. This elicited a serious production crisis worldwide, that caused losses of millions of dollars for farmers in many countries, including the Mesoamerican region. Fortunately, in Costa Rica, some local research centers, with the collaboration of foreign specialists, have been able to study the causes of this phenomenon, in the search for solutions based on solid epidemiological information. In addition to the previously reported native Bemisia tabaci species, New World (NW), two exotic species, -Mediterranean (MED) and Middle East-Asia Minor 1 (MEAM1)- were found. Moreover, native and exotic bipartite begomoviruses have been detected, especially in common bean, cucurbits, tomato and sweet pepper, as well as the worldwide spread monopartite begomovirus Tomato yellow leaf curl virus (TYLCV). Based upon biological and ecological knowledge accumulated to date, this review offers a comprehensive overview of the very dynamic ways in which the interactions of the different whiteflies and begomovirus species have expressed in Costa Rica, with emphasis on vegetable pathosystems. Hopefully, the information provided in this paper may allow farmers, extension agents, and researchers involved in vegetable production to develop sound practical responses to current and unforeseen problems regarding whiteflies and their associated viruses.
Desde inicios del decenio de 1990 y de manera casi simultánea, se empezaron a observar afecciones desconocidas en numerosos cultivos, sobre todo en regiones tropicales y subtropicales. Dichas enfermedades eran causadas por begomovirus hasta entonces poco estudiados. Su vector es la mosca blanca Bemisia tabaci (Hemiptera: Aleyrodidae), de la que no se habían registrado poblaciones tan desmedidas en áreas agrícolas. Ello originó una seria crisis de producción a nivel mundial, con pérdidas millonarias para los agricultores de numerosos países, incluyendo la región de Mesoamérica. Por fortuna, en Costa Rica, algunos centros de investigación, con la colaboración de especialistas extranjeros, han podido profundizar en las causas de este fenómeno, para buscar soluciones fundamentadas en información de carácter epidemiológico. Además de la especie de B. tabaci New World (NW), nativa y previamente conocida, en años recientes han ingresado sendas especies del Mediterráneo (MED) y el Medio Oriente-Asia Menor 1 (MEAM1). Asimismo, se ha detectado la presencia de begomovirus bipartitas, nativos y exóticos, especialmente en frijol común, cucurbitáceas, tomate y chile; además, se detectó el begomovirus monopartito conocido a nivel mundial Tomato yellow leaf curl virus (TYLCV) en tomate. Con base en el conocimiento biológico y ecológico acumulado hasta ahora, en la presente revisión se aporta una panorámica del dinamismo con que se han expresado en Costa Rica las interacciones entre las diferentes especies vectoras y los distintos begomovirus, con énfasis en patosistemas de hortalizas. Se espera que la información aquí presentada permita mejorar el tipo de respuestas prácticas y eficaces de parte de agricultores, extensionistas agrícolas e investigadores involucrados en la producción de hortalizas, frente a problemas actuales o imprevistos.
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The present study investigated the antineoplastic effects of pectic polysaccharides that were extracted from green sweet pepper (Capsicum annuum [CAP]) in the Ehrlich carcinoma in mice and in human mammary tumor lineages. After the subcutaneous inoculation of 2 × 106 Ehrlich tumor cells, Female Swiss mice received 50, 100, or 150 mg/kg CAP or vehicle orally once daily or methotrexate (2.5 mg/kg, i.p., every 5 days) for 21 days. CAP dose-dependently reduced Ehrlich tumor growth. It also reduced the viability of MCF-7, MDA-MB-231, and MDA-MB-436 human mammary cell lineages. Treatment with CAP reduced the gene expression of vascular endothelial growth factor in vivo and in vitro, reduced vessel areas of the tumors, and induced necrosis in Ehrlich solid tumors. CAP treatment significantly increased Interleukin-6 in tumors. The antineoplastic effect of CAP appears to depend on the regulation of inflammation and angiogenesis. Further studies are encouraged to better understand the CAP potential for the treatment of breast tumors.
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Antineoplásicos Fitogénicos , Neoplasias de la Mama/tratamiento farmacológico , Capsicum/química , Carcinoma de Ehrlich/tratamiento farmacológico , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Pectinas , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/patología , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células MCF-7 , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Pectinas/química , Pectinas/aislamiento & purificación , Pectinas/farmacologíaRESUMEN
Pectins can modulate the biological responses interacting directly with immune cells. The observed responses can strongly be affected by polysaccharide structural features. We analyzed the intrinsic activation capacity of native and modified sweet pepper pectin on cytokine secretion by THP-1 macrophages as well as compare their effects in the presence of lipopolysaccharide. Modified pectin was obtained by partial acid hydrolysis which promoted the removal of side chains as well as the reduction of molecular weight and the degree of methyl esterification of native pectin. The results showed that both fractions had no effect on THP-1 viability. Native pectin at 300µg/mL increased TNF-α, IL-1ß and IL-10 cytokine secretion by THP-1 macrophages. However, in the presence of lipopolysaccharide, it can attenuate the inflammatory response by reducing the production of the pro-inflammatory cytokines TNF-α and IL-1ß and increasing the anti-inflammatory cytokine IL-10, as well as decreasing the TNF-α/IL-10 and IL-1ß/IL-10 ratios. The structural modifications caused by acid hydrolysis affected the intrinsic activation capacity of native pectin to modulate the cytokines secretion. These results indicate that degree of methyl esterification, molecular weight and presence of side chains are important structural features of pectins involved in the modulation of cytokine secretion by THP-1 macrophages.
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Capsicum/química , Citocinas/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Pectinas/química , Pectinas/farmacología , Humanos , Hidrólisis , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/inmunología , Relación Estructura-Actividad , Células THP-1 , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Polysaccharides were extracted from sweet pepper (Capsicum annum) with hot water and named ANW (9% yield). Starch was precipitated by freeze-thaw treatment, while pectic polysaccharides (8% yield) remained soluble and consisted of GalA (67.0%), Rha (1.6%), Ara (6.4%), Xyl (0.3%), Gal (6.7%) and Glc (4.4%). A highly methoxylated homogalacturonan (HG, degree of methylesterification of 85% and degree of acetylation of 5%), and type I and type II arabinogalactans (AG-I and AG-II) were observed in NMR analyses. These were fractionated with Fehling's solution to give HG (5.5% yield) and AG fractions (0.6% yield). AG-I and AG-II were further separated by ultrafiltration. AG-II (0.2% yield) consisted of Ara (17.1%), Gal (36.0%), Rha (5.6%) and GalA (12.0%), had a molecular weight of 5.3×104g/mol and methylation and 1H/13C HSQC-DEPT-NMR analyses showed that it was anchored in type I rhamnogalacturonan. This is the first study that reports the presence of AG-I and AG-II in sweet pepper fruits.
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Capsicum/química , Galactanos/química , Pectinas/química , PolisacáridosRESUMEN
Bell pepper is an economically important crop worldwide; however, production is restricted by a number of fungal diseases that cause significant yield loss. Chemical control is the most common approach adopted by growers to manage a number of these diseases. Monitoring for the development to resistance to fungicides in pathogenic fungal populations is central to devising integrated pest management strategies. Two fungal species, Fusarium incarnatum-equiseti species complex (FIESC) and Colletotrichum truncatum are important pathogens of bell pepper in Trinidad. This study was carried out to determine the sensitivity of 71 isolates belonging to these two fungal species to fungicides with different modes of action based on in vitro bioassays. There was no significant difference in log effective concentration required to achieve 50% colony growth inhibition (LogEC50) values when field location and fungicide were considered for each species separately based on ANOVA analyses. However, the LogEC50 value for the Aranguez-Antracol location-fungicide combination was almost twice the value for the Maloney/Macoya-Antracol location-fungicide combination regardless of fungal species. LogEC50 values for Benomyl fungicide was also higher for C. truncatum isolates than for FIESC isolates and for any other fungicide. Cropping practices in these locations may explain the fungicide sensitivity data obtained.
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BACKGROUND: The evaluation of lethal and sublethal effects is of great importance for a complete assessment of the total impact of chemical compounds upon pest populations and the development of management strategies. In this study, we evaluated the lethal and sublethal effects of different synthetic and botanical products on the broad mite Polyphagotarsonemus latus (Banks), a major pest of Capsicum annuum L. and other crops. RESULTS: Abamectin had the highest lethal effect on P. latus, followed by spiromesifen, azadirachtin, neem oil and nitrogen fertiliser + citric acid. The sublethal effects of the products were indicated by the influence on mite population growth, affecting the numbers of females, males, larvae, pupae and eggs. Furthermore, a negative instantaneous rate of increase in P. latus and repellent effects were observed. CONCLUSION: The lethal and sublethal effects of abamectin, spiromesifen, azadirachtin and neem oil significantly affect P. latus population growth, as well as causing repellence to this mite on C. annuum, and they should be considered in the integrated pest management of this mite. © 2017 Society of Chemical Industry.
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Acaricidas , Capsicum , Ácaros , Control de Ácaros y Garrapatas , Animales , Capsicum/crecimiento & desarrollo , Femenino , Larva , Masculino , Ácaros/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Pupa/crecimiento & desarrolloRESUMEN
Despite the continued efforts on the search for different genotypes, Capsicum annuum (L.) is quite susceptible to attack by pest arthropods, especially the broad mite Polyphagotarsonemus latus Banks. Thus, the host preference, population growth and the injuries assessment of P. latus was studied on six C. annuum genotypes used in Brazil (Atlantis, California Wonder, Impact, Palloma, Rubia and Tendence). Host preference was accessed in choice tests, pairing the several genotypes, and the population growth was observed through non-choice tests in laboratory. The injuries assessments were evaluated in the greenhouse, comparing the injury level among the six genotypes. The results indicate that California Wonder and Palloma genotypes were more preferred by P. latus, and Impact and Tendence were less preferred. P. latus presented positive population growth rates (ri) on all the genotypes, however, Palloma and California Wonder showed the highest values of population growth rate (ri = 0.344 and ri = 0.340, respectively), while Impact had the lowest value (ri = 0.281). All the evaluated C. annuum genotypes showed low tolerance to P. latus and exhibited several injuries, but there was no statistical difference between them. California Wonder had the highest average number of mites/leaf (57.15), while Impact and Tendence obtained the lowest values (36.67 and 35.12, respectively) at the end of the evaluation period. The total average of injuries notes at the end of the bioassay did not differ between the genotypes. The number of mites/leaf was growing for the injury scale to the note 3.0, but when the injury scale approached the note 4.0, there was observed a decrease in the number of mites/leaf for all the genotypes.
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Capsicum/fisiología , Herbivoria , Ácaros/fisiología , Animales , Brasil , Capsicum/genética , Preferencias Alimentarias , Genotipo , Especificidad del Huésped , Densidad de PoblaciónRESUMEN
The bacterial wilt caused by Ralstonia solanacearum is one of the most important in the genus Capsicum in Brazil. In the state of Amazonas, high temperatures and humidity favor the development of the disease. The objective of this work was to evaluate resistance in germoplasm of wild and commercial Capsicum spp. to bacterial wilt. Twenty two accesses of Capsicum spp. were evaluated in greenhouse conditions. The inoculation was made by means of wounds in the roots, followed by addition of bacterial suspension in the concentration of 10(8) ufc ml-1 in the soil, around the plants. Plant evaluation was made daily after the fourth day of the inoculation (DAI) considering the symptoms progress. From the average progress of symptoms was constructed the area under the disease progress curve (AUDPC), and the data submitted to the Scott-Knott test at 5% of probability, using SAEG statistical program. From the average severity notes, we constructed the area under the disease progress curve (AUDPC). The accesses 30, 20 and 17 were selected from C. chinense as resistant to the bacterial wilt, for future use in genetic breeding programs.
A murcha bacteriana, causada por Ralstonia solanacearum, é uma das doenças mais importantes do gênero Capsicum no Brasil. No Amazonas, as condições de elevada temperatura e umidade favorecem o desenvolvimento da doença. O objetivo deste trabalho foi avaliar a resistência à murcha bacteriana de germoplasma, selvagem e comercial, de Capsicum spp. Foram avaliados 22 acessos de Capsicum em casa de vegetação. A inoculação foi feita mediante ferimento das raízes, seguido de adição no solo, ao redor das plantas, de suspensão bacteriana na concentração de 10(8) ufc mL-1. A avaliação foi feita diariamente a partir do quarto dia após a inoculação, em função desenvolvimento dos sintomas. A partir das médias de progresso dos sintomas foi construída a área abaixo da curva de progresso da doença (AACPD), e os dados submetidos ao teste de Scott-Knott ao nível de 5% de probabilidade, utilizando o programa estatístico SAEG 9.1. Foram selecionados os acessos 30, 20 e 17, da espécie C. chinense, como resistentes à murcha bacteriana para ensaios futuros em programas de melhoramento genético.
RESUMEN
A murcha bacteriana, causada por Ralstonia solanacearum, é uma das doenças mais importantes do gênero Capsicum no Brasil. No Amazonas, as condições de elevada temperatura e umidade favorecem o desenvolvimento da doença. O objetivo deste trabalho foi avaliar a resistência à murcha bacteriana de germoplasma, selvagem e comercial, de Capsicum spp. Foram avaliados 22 acessos de Capsicum em casa de vegetação. A inoculação foi feita mediante ferimento das raízes, seguido de adição no solo, ao redor das plantas, de suspensão bacteriana na concentração de 10(8) ufc mL-1. A avaliação foi feita diariamente a partir do quarto dia após a inoculação, em função desenvolvimento dos sintomas. A partir das médias de progresso dos sintomas foi construída a área abaixo da curva de progresso da doença (AACPD), e os dados submetidos ao teste de Scott-Knott ao nível de 5 por cento de probabilidade, utilizando o programa estatístico SAEG 9.1. Foram selecionados os acessos 30, 20 e 17, da espécie C. chinense, como resistentes à murcha bacteriana para ensaios futuros em programas de melhoramento genético.
The bacterial wilt caused by Ralstonia solanacearum is one of the most important in the genus Capsicum in Brazil. In the state of Amazonas, high temperatures and humidity favor the development of the disease. The objective of this work was to evaluate resistance in germoplasm of wild and commercial Capsicum spp. to bacterial wilt. Twenty two accesses of Capsicum spp. were evaluated in greenhouse conditions. The inoculation was made by means of wounds in the roots, followed by addition of bacterial suspension in the concentration of 10(8) ufc ml-1 in the soil, around the plants. Plant evaluation was made daily after the fourth day of the inoculation (DAI) considering the symptoms progress. From the average progress of symptoms was constructed the area under the disease progress curve (AUDPC), and the data submitted to the Scott-Knott test at 5 percent of probability, using SAEG statistical program. From the average severity notes, we constructed the area under the disease progress curve (AUDPC). The accesses 30, 20 and 17 were selected from C. chinense as resistant to the bacterial wilt, for future use in genetic breeding programs.
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Capsicum , Pimenta , Ralstonia solanacearumRESUMEN
Conduziu-se este trabalho, com o objetivo de avaliar a capacidade de combinação de linhagens elite de pimentão (Capisicum annuum L.), identificar combinações híbridas superiores quanto à qualidade de frutos, e inferir sobre os modos de ação gênica envolvidos na expressão dos caracteres relacionados à qualidade dos frutos. Para isto, foram realizados cruzamentos dialélicos para obtenção de híbridos, sendo analisados segundo o esquema dialélico parcial tipo North Carolina II, estimando-se a capacidade geral (CGC) de cada genitor dentro de cada grupo, bem como as capacidades específicas (CEC) de combinação para cada combinação de genitores. Os híbridos experimentais apresentaram heterose para diâmetro de fruto e profundidade de inserção de pedúnculo. A característica profundidade de inserção do pedúnculo é condicionada, predominantemente, por alelos recessivos. Os melhores híbridos, com perspectivas para uso comercial foram F1 (L-3436 x L-004), F1 (L-3513 x L-004) e F1 (L-3509 x L-004). Foram obtidos valores positivos de heterose padrão variando de 1,47 a 30,04 por cento para diâmetro de fruto, de 2,57 a 83,71 por cento para profundidade de inserção do pedúnculo, em relação à cultivar híbrida F1 Magali-R.
The work had the aim to evaluating the combining ability among sweet pepper breeding lines, identify superior hybrids for fruit quality, and to infer on the mode of gene action involved in the expression fruit quality. North Carolina-II scheme partial diallel crosses were obtained, to estimate general combining abilities (GCA) of parental lines and specific combining abilities (SCA) of parental combinations. There was evidence for heterosis among experimental hybrids for fruit diameter and insertion depth of the peduncle. Peduncle insertion depth is conditioned, predominantly, by recessive alleles. Experimental hybrids with commercial potential were F1 (L-3436 x L-004), F1 (L-3513 x L-004) and F1 (L-3509 x L-004). Heterosis values relative to the standard cultivar Magali-R-F1 ranged from 1.47 percent to 30.04 percent for fruit diameter and 2.57 percent to 83.71 percent for insertion depth of the peduncle.
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The use of fungicides to control powdery mildew in sweet pepper has been ineffective and genetic resistance is the best alternative. Resistance sources identified in Capsicum annuum L. are rare and unsatisfactory. The purpose of this work was to study the inheritance of C. annuum reaction to powdery mildew. Three homozygous powdery mildew resistant parents, HV-12, Chilli and /124 and three susceptible lines, 609, 442 and 428 were used to obtain seven F1's and respectively their generations F2: HV-12 x 609, 442 × HV-12, 428 × HV-12, Chilli × 609, /124 × 609, Chilli × HV-12 and /124 × HV-12. The powdery epidemic was natural using inoculum from highly sporulating susceptible pepper host. Powdery mildew host reaction evaluations were carried out during the fruit production using a rating system based on disease severity scales varying from 1 (resistant) to 5 (highly susceptible). The experimental design was completely randomized. The following genetic parameters were estimated: locus numbers, gene action, heritability coefficient, expected selection gain and observed progress in F3 generation, and possibly allelic relationship among resistance genes of different resistance sources. The HV-12×609 cross was the only one that showed absence of dominance. Other genetically analyzed crossings showed dominant and epistatic effects. Resistance was characterized as being due to at least four pairs of genes. The heritability and selection gains estimates were high. The resistance mechanisms of /124, Chilli and HV-12 showed differences in their expression.
O uso de fungicidas no controle do oídio do pimentão tem se mostrado ineficaz, sendo a resistência genética a melhor alternativa. As fontes de resistência identificadas em Capsicum annuum L. são raras e não satisfatórias. O objetivo deste trabalho foi estudar a herança da reação de C. annuum ao oídio. Três progenitores resistentes e homozigóticos, HV-12, Chilli e /124 e três suscetíveis, 609, 442 e 428 foram usados na obtenção de sete híbridos e respectivas gerações F2: HV-12 × 609, 442 × HV-12, 428 × HV-12, Chilli × 609, /124 × 609, Chilli × HV-12 e /124 × HV-12. A epidemia de oídio ocorreu de maneira natural a partir de inóculo mantido em plantas de pimentão suscetíveis. As avaliações das reações ao oídio foram feitas na fase de frutificação, através de uma escala de notas de 1 (resistente) a 5 (altamente suscetível). O delineamento experimental utilizado foi inteiramente casualizado. Foram estimados, os números de locos, ação gênica, coeficiente de herdabilidade, ganho de seleção esperado e o progresso observado em F3 e possíveis relações de alelismo entre os genes que governam a resistência. O cruzamento HV-12 × 609 foi o único em que a reação de resistência mostrou ausência de dominância. Nos demais cruzamentos detectaram-se efeitos dominantes e epistáticos. A herança foi caracterizada sendo governada por no mínimo quatro pares de genes. As herdabilidades e ganhos de seleção estimados foram altos. O mecanismo de resistência dos progenitores resistentes /124, Chilli e HV-12 mostraram diferenças de expressão e natureza genética.
RESUMEN
The use of fungicides to control powdery mildew in sweet pepper has been ineffective and genetic resistance is the best alternative. Resistance sources identified in Capsicum annuum L. are rare and unsatisfactory. The purpose of this work was to study the inheritance of C. annuum reaction to powdery mildew. Three homozygous powdery mildew resistant parents, HV-12, Chilli and /124 and three susceptible lines, 609, 442 and 428 were used to obtain seven F1's and respectively their generations F2: HV-12 x 609, 442 × HV-12, 428 × HV-12, Chilli × 609, /124 × 609, Chilli × HV-12 and /124 × HV-12. The powdery epidemic was natural using inoculum from highly sporulating susceptible pepper host. Powdery mildew host reaction evaluations were carried out during the fruit production using a rating system based on disease severity scales varying from 1 (resistant) to 5 (highly susceptible). The experimental design was completely randomized. The following genetic parameters were estimated: locus numbers, gene action, heritability coefficient, expected selection gain and observed progress in F3 generation, and possibly allelic relationship among resistance genes of different resistance sources. The HV-12×609 cross was the only one that showed absence of dominance. Other genetically analyzed crossings showed dominant and epistatic effects. Resistance was characterized as being due to at least four pairs of genes. The heritability and selection gains estimates were high. The resistance mechanisms of /124, Chilli and HV-12 showed differences in their expression.
O uso de fungicidas no controle do oídio do pimentão tem se mostrado ineficaz, sendo a resistência genética a melhor alternativa. As fontes de resistência identificadas em Capsicum annuum L. são raras e não satisfatórias. O objetivo deste trabalho foi estudar a herança da reação de C. annuum ao oídio. Três progenitores resistentes e homozigóticos, HV-12, Chilli e /124 e três suscetíveis, 609, 442 e 428 foram usados na obtenção de sete híbridos e respectivas gerações F2: HV-12 × 609, 442 × HV-12, 428 × HV-12, Chilli × 609, /124 × 609, Chilli × HV-12 e /124 × HV-12. A epidemia de oídio ocorreu de maneira natural a partir de inóculo mantido em plantas de pimentão suscetíveis. As avaliações das reações ao oídio foram feitas na fase de frutificação, através de uma escala de notas de 1 (resistente) a 5 (altamente suscetível). O delineamento experimental utilizado foi inteiramente casualizado. Foram estimados, os números de locos, ação gênica, coeficiente de herdabilidade, ganho de seleção esperado e o progresso observado em F3 e possíveis relações de alelismo entre os genes que governam a resistência. O cruzamento HV-12 × 609 foi o único em que a reação de resistência mostrou ausência de dominância. Nos demais cruzamentos detectaram-se efeitos dominantes e epistáticos. A herança foi caracterizada sendo governada por no mínimo quatro pares de genes. As herdabilidades e ganhos de seleção estimados foram altos. O mecanismo de resistência dos progenitores resistentes /124, Chilli e HV-12 mostraram diferenças de expressão e natureza genética.
RESUMEN
The objective of this work was to evaluate the effect N and K2O on the production and yield of sweet pepper plants, related to the characteristics of growth (weight, lenght and diameter) and total number of fruits per plant, per area. Nitrogen (urea) and potassium (KCl) fertilizers were side dressed in six applications to sweet pepper cultivar Mayata, cultivated in a protected environment. The experiment was conducted from November/96 to August/97, with the following treatments: control and combination of three rates of N (13.3, 26.6, and 39.9 g m-2) and three rates of K2O (13.3, 26.6 and 39.9 g m-2). The experimental design consisted of randomized blocks, in a factorial scheme (3 x 3 + 1), with four replications with a total of 40 plots. Each plot comprised 11 plants, totalizing of 444 plants. Plants were grown with drip irrigation along the entire cycle of the crop. Fruits were harvest when ripe, ready for consumption. Nitrogen fertilizer increased the maximun dry matter of the stem, leaves and roots, but not of fruit dry matter production. The optimal rate for maximum dry matter accumulation of N was 27.0 g m-2. Nitrogen did not affect the growth characteristics of the commercial fruits, such as weight, length, and diameter. Therefore did not affect the yield of commercial fruits. The favorable effect of the nitrogen on the production of total dry matter and yield occurred only at low concentrations of potassium in the soil (13.3 gm-2) and a minimum development of sweet pepper with 33,0 g m-2 de K2O in the soil.
O objetivo deste trabalho foi avaliar o efeito do N e K2O na produtividade e rendimento do pimentão, em função de características de crescimento dos frutos (peso, comprimento e diâmetro) e do número total de frutos por planta e por área. Os tratamentos foram aplicados sob condições de ambiente protegido, ao lado da linha de plantas e parcelados em 6 vezes, utilizando-se a cultivar Mayata. O experimento foi conduzido de novembro/96 a agosto/97 e constou dos seguintes tratamentos: controle e as combinações de 3 doses de N (13,3; 26,6 e 39,9 g m-2) e 3 doses de K2O (13,3; 26,6 e 39,9 g m-2). O delineamento experimental adotado foi o de blocos ao acaso, em esquema fatorial (3 x 3 +1), com 4 repetições, totalizando 40 parcelas. Cada parcela foi composta de 11 plantas, totalizando 444 plantas. Foram realizados todos os tratos culturais recomendados para a cultura do pimentão, incluindo irrigação por gotejamento. Os frutos foram colhidos recém maduros, ao atingirem ponto de consumo. Com base nos resultados, concluiu-se que a adubação nitrogenada aumentou a produção total de matéria seca das plantas (caule, folhas e raízes), embora não tenha afetado a produção de matéria seca dos frutos. O nível ótimo estimado de acúmulo de M. seca ocorreu na dose de 27,0 g m-2 de N. A aplicação de N no solo não influenciou significativamente, as características de crescimento dos frutos, como peso, comprimento e diâmetro, nem o rendimento de frutos comerciais; o efeito favorável do N na produção de matéria seca das plantas e rendimento dos frutos, ocorreu somente em baixas doses de K2O no solo (13,3 g m-2), aplicado como KCl. As maiores doses de K2O tiveram um efeito depressivo para os mesmos parâmetros, havendo um mínimo de crescimento vegetativo com a dose estimada de 33,0 g m-2 de K2O.
RESUMEN
The objective of this work was to evaluate the effect N and K2O on the production and yield of sweet pepper plants, related to the characteristics of growth (weight, lenght and diameter) and total number of fruits per plant, per area. Nitrogen (urea) and potassium (KCl) fertilizers were side dressed in six applications to sweet pepper cultivar Mayata, cultivated in a protected environment. The experiment was conducted from November/96 to August/97, with the following treatments: control and combination of three rates of N (13.3, 26.6, and 39.9 g m-2) and three rates of K2O (13.3, 26.6 and 39.9 g m-2). The experimental design consisted of randomized blocks, in a factorial scheme (3 x 3 + 1), with four replications with a total of 40 plots. Each plot comprised 11 plants, totalizing of 444 plants. Plants were grown with drip irrigation along the entire cycle of the crop. Fruits were harvest when ripe, ready for consumption. Nitrogen fertilizer increased the maximun dry matter of the stem, leaves and roots, but not of fruit dry matter production. The optimal rate for maximum dry matter accumulation of N was 27.0 g m-2. Nitrogen did not affect the growth characteristics of the commercial fruits, such as weight, length, and diameter. Therefore did not affect the yield of commercial fruits. The favorable effect of the nitrogen on the production of total dry matter and yield occurred only at low concentrations of potassium in the soil (13.3 gm-2) and a minimum development of sweet pepper with 33,0 g m-2 de K2O in the soil.
O objetivo deste trabalho foi avaliar o efeito do N e K2O na produtividade e rendimento do pimentão, em função de características de crescimento dos frutos (peso, comprimento e diâmetro) e do número total de frutos por planta e por área. Os tratamentos foram aplicados sob condições de ambiente protegido, ao lado da linha de plantas e parcelados em 6 vezes, utilizando-se a cultivar Mayata. O experimento foi conduzido de novembro/96 a agosto/97 e constou dos seguintes tratamentos: controle e as combinações de 3 doses de N (13,3; 26,6 e 39,9 g m-2) e 3 doses de K2O (13,3; 26,6 e 39,9 g m-2). O delineamento experimental adotado foi o de blocos ao acaso, em esquema fatorial (3 x 3 +1), com 4 repetições, totalizando 40 parcelas. Cada parcela foi composta de 11 plantas, totalizando 444 plantas. Foram realizados todos os tratos culturais recomendados para a cultura do pimentão, incluindo irrigação por gotejamento. Os frutos foram colhidos recém maduros, ao atingirem ponto de consumo. Com base nos resultados, concluiu-se que a adubação nitrogenada aumentou a produção total de matéria seca das plantas (caule, folhas e raízes), embora não tenha afetado a produção de matéria seca dos frutos. O nível ótimo estimado de acúmulo de M. seca ocorreu na dose de 27,0 g m-2 de N. A aplicação de N no solo não influenciou significativamente, as características de crescimento dos frutos, como peso, comprimento e diâmetro, nem o rendimento de frutos comerciais; o efeito favorável do N na produção de matéria seca das plantas e rendimento dos frutos, ocorreu somente em baixas doses de K2O no solo (13,3 g m-2), aplicado como KCl. As maiores doses de K2O tiveram um efeito depressivo para os mesmos parâmetros, havendo um mínimo de crescimento vegetativo com a dose estimada de 33,0 g m-2 de K2O.
RESUMEN
The effect of floating on the growth of sweet pepper kept in styrofoam trays of 128 cells was studied. The floating contained soluble fertiliser 20-10-20 in a concentration of 1g/L. After germination the trays were tested in different conditions as following: C1- trays kept on the bench and watered by spray twice a day; C2- same as C1 and plants fertilized three times a week (500 ml/tray); C3-trays kept 12 hours on the bench and 12 hours floating; C4- trays kept floating during the experiment except for the last week; C5- trays kept floating during the whole experiment; C6- same as C5 and plants watered three times a week with 500 ml/tray of soluble fertiliser from the floating system. The experimental design was completely randomised with 6 treatments and 4 replicates, with 10 plants in each plot. The parameters evaluated were: plant height, root lenght, fresh and dry weight of plant root. The highest values of these parameters were obtained for treatments C4, C5 and C6.
Foi estudado o efeito do "floating" no condicionamento do crescimento de mudas de pimentão produzidas em bandejas de isopor de 128 células. Foi utilizado o sistema de "floating" contendo uma solução de adubo solúvel 20-10-20 na concentração de 1g/L. A semeadura foi feita diretamente em bandejas de isopor. Após a germinação as bandejas foram submetidas aos diferentes condicionamentos: C1 - As bandejas permaneceram sempre fora do "floating" recebendo aspersão de água 2 vezes ao dia; C2 - Idem C1 mais irrigação da mesma solução do "floating" 3 vezes por semana usando-se 500ml de solução por bandeja; C3 - A cada dia as bandejas ficaram 12h dentro do "floating" e 12h fora; C4-As bandejas permaneceram todo o período do ensaio dentro do "floating", exceto a última semana; C5-As bandejas permaneceram todo o período dentro do "floating"; C6-Idem C5 mais irrigação com a mesma solução do "floating" 3 vezes por semana usando-se 500ml de solução por bandeja. O delineamento experimental foi inteiramente casualizado, com 6 tratamentos e 4 repetições, com 10 plantas em cada parcela. Os parâmetros de desenvolvimento avaliados foram: altura da planta, comprimento da raiz, peso da matéria fresca da raiz, peso da matéria fresca da parte aérea, peso da matéria seca da raiz, peso da matéria seca da parte aérea. Os valores mais elevados dos parâmetros avaliados foram obtidos nos condicionamentos C4, C5 e C6.