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Toxicity of anthranilamides used in cucurbit cultivation on Apis mellifera
Get PDFThis study aimed to evaluate the toxicity of insecticides belonging to the chemical group Anthranilamide on Apis mellifera. Toxicity was evaluated in the two experiments, which corresponded to two exposure modes: direct spraying of the products on the bees and ingestion of a contaminated diet. The two bioassays were performed in a completely randomized design composed of eight treatments (absolute control – distilled water; positive control: Thiamethoxam at 0.03 and 0.3 g.a.i. L-1; Chlorantraniliprole: 0.015 g.a.i. L-1; Cyantraniliprole: 0.05 and 0.1 g.a.i. L-1; Chlorantraniliprole + Abamectin: 0.027+0.0108 g.a.i. L-1 and 0.045+0.018 g.a.i. L-1), with 10 replications each. Via exposure through direct spraying, the insecticide Chlorantraniliprole + Abamectin, regardless of the dose used, caused 100% bee mortality, showing a TL50 of 10.05h and 8.36h for the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 33.1% and 44.9% of the bees, respectively at the minimum and maximum doses, with a TL50 of 87.79 h for the two doses. The insecticide Chlorantraniliprole showed the lowest mortality rate, 24.7%, with a TL50 of 118.88h. Via ingestion of a contaminated diet, the insecticide Chlorantraniliprole + Abamectin caused 100% mortality and showed a TL50 of 27.83h and 24.01h at the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 67.6% and 68.1% of bees at the minimum and maximum doses, respectively, with a TL50 of 58.63 h for the two doses. Chlorantraniliprole shows the lowest mortality rate, 48.1%, and a TL50 of 79.68h.This study aimed to evaluate the toxicity of insecticides belonging to the chemical group Anthranilamide on Apis mellifera. Toxicity was evaluated in the two experiments, which corresponded to two exposure modes: direct spraying of the products on the bees and ingestion of a contaminated diet. The two bioassays were performed in a completely randomized design composed of eight treatments (absolute control – distilled water; positive control: Thiamethoxam at 0.03 and 0.3 g.a.i. L-1; Chlorantraniliprole: 0.015 g.a.i. L-1; Cyantraniliprole: 0.05 and 0.1 g.a.i. L-1; Chlorantraniliprole + Abamectin: 0.027+0.0108 g.a.i. L-1 and 0.045+0.018 g.a.i. L-1), with 10 replications each. Via exposure through direct spraying, the insecticide Chlorantraniliprole + Abamectin, regardless of the dose used, caused 100% bee mortality, showing a TL50 of 10.05h and 8.36h for the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 33.1% and 44.9% of the bees, respectively at the minimum and maximum doses, with a TL50 of 87.79 h for the two doses. The insecticide Chlorantraniliprole showed the lowest mortality rate, 24.7%, with a TL50 of 118.88h. Via ingestion of a contaminated diet, the insecticide Chlorantraniliprole + Abamectin caused 100% mortality and showed a TL50 of 27.83h and 24.01h at the minimum and maximum doses, respectively. The insecticide Cyantraniliprole caused the death of 67.6% and 68.1% of bees at the minimum and maximum doses, respectively, with a TL50 of 58.63 h for the two doses. Chlorantraniliprole shows the lowest mortality rate, 48.1%, and a TL50 of 79.68h
Production and quality of ornamental peppers cultivated under colored shade nets
Get PDFThe cultivation of ornamental peppers in places with high temperature and incidence of solar radiation limits the production and quality of plants and fruits. The colored shade nets were introduced and adopted, because they reduce the temperature and intensity of solar radiation, as well as, low cost and simple to handle. The aimed was to evaluate the production and quality of C. chinense and C. frutescens cultivated under colored shade nets. The experiment was developed in the Floriculture Sector of the Agronomy Department of the Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil from February to August 2021 in entirely randomized design. C. chinense and C. frutescens were cultivated under red, pearl and aluminet nets with 35% shading and without net. At 150 days, production variables were quantified. The red net reduced the maximum temperature by at 4.1ºC and the pearl and aluminet nets reduced the minimum temperature by 3ºC. The maximum and minimum relative humidity was increased by 2.6 and 8.5%, respectively, by the red net. The pearl net obtained the lowest percentage of solar radiation incidence. Plant height was greater in the red and pearl nets, and C. frutescens. The diameter and stem fresh matter did not differ statistically between treatments. Root length was greater in the red and aluminet nets. The longitudinal and transverse canopy ratio was higher in C. chinense cultivated under the aluminet net. The number of leaves and leaves fresh matter was higher in pearl and aluminet net, and in C. frutescens, but leaves dry matter was higher in C. chinense. The number of flower buds and flowers, and flower buds dry matter was higher in C. chinense. The root fresh matter and dry matter was greater in C. chinese. The use of colored shade nets during the cultivation period effectively reduced temperature and light intensity. The aluminet net in association with C. chinense are recommended considering the compactness of height, pot coverage, greater number, shape and arrangement of fruits.The cultivation of ornamental peppers in places with high temperature and incidence of solar radiation limits the production and quality of plants and fruits. The colored shade nets were introduced and adopted, because they reduce the temperature and intensity of solar radiation, as well as, low cost and simple to handle. The aimed was to evaluate the production and quality of C. chinense and C. frutescens cultivated under colored shade nets. The experiment was developed in the Floriculture Sector of the Agronomy Department of the Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil from February to August 2021 in entirely randomized design. C. chinense and C. frutescens were cultivated under red, pearl and aluminet nets with 35% shading and without net. At 150 days, production variables were quantified. The red net reduced the maximum temperature by at 4.1ºC and the pearl and aluminet nets reduced the minimum temperature by 3ºC. The maximum and minimum relative humidity was increased by 2.6 and 8.5%, respectively, by the red net. The pearl net obtained the lowest percentage of solar radiation incidence. Plant height was greater in the red and pearl nets, and C. frutescens. The diameter and stem fresh matter did not differ statistically between treatments. Root length was greater in the red and aluminet nets. The longitudinal and transverse canopy ratio was higher in C. chinense cultivated under the aluminet net. The number of leaves and leaves fresh matter was higher in pearl and aluminet net, and in C. frutescens, but leaves dry matter was higher in C. chinense. The number of flower buds and flowers, and flower buds dry matter was higher in C. chinense. The root fresh matter and dry matter was greater in C. chinese. The use of colored shade nets during the cultivation period effectively reduced temperature and light intensity. The aluminet net in association with C. chinense are recommended considering the compactness of height, pot coverage, greater number, shape and arrangement of fruits
Increasing levels of cassava wastewater in the production of papaya formosa seedlings
Get PDFCassava wastewater (CWW) is rich in nutrients for plants, presenting great potential as an alternative fertilizer. However, this waste is incorrectly disposed of in the environment, which causes environmental problems. The objective was to evaluate the influence of increasing doses of CWW on the production of formosa papaya seedlings. The experiment was installed in a greenhouse from October 22 to December 5, 2019, in which a completely randomized design was applied with 4 treatments of different levels of CWW with 0 ml L-1, 6.25 ml L-1, 12.5 ml L-1, 25 ml L-1, where each treatment contained 4 replicates of 4 seedlings. Biometric parameters were evaluated to identify the effects of CWW on initial papaya growth. Data were subjected to analysis of variance by F test, and data were explored through regression analysis. Significance was found for root length (RL) and root diameter (RD). The other biometric parameters did not respond to the tested doses of CWW. The tested doses reduced the RL and the DR had the best performance with the dose of 13.5 ml L-1. 13.5 ml L-1 of cassava effluents is recommended for better development of DR. In general, this residue has an inhibitory effect on the initial growth of the papaya tree and is not recommended for the production of seedlings of this species.Cassava wastewater (CWW) is rich in nutrients for plants, presenting great potential as an alternative fertilizer. However, this waste is incorrectly disposed of in the environment, which causes environmental problems. The objective was to evaluate the influence of increasing doses of CWW on the production of formosa papaya seedlings. The experiment was installed in a greenhouse from October 22 to December 5, 2019, in which a completely randomized design was applied with 4 treatments of different levels of CWW with 0 ml L-1, 6.25 ml L-1, 12.5 ml L-1, 25 ml L-1, where each treatment contained 4 replicates of 4 seedlings. Biometric parameters were evaluated to identify the effects of CWW on initial papaya growth. Data were subjected to analysis of variance by F test, and data were explored through regression analysis. Significance was found for root length (RL) and root diameter (RD). The other biometric parameters did not respond to the tested doses of CWW. The tested doses reduced the RL and the DR had the best performance with the dose of 13.5 ml L-1. 13.5 ml L-1 of cassava effluents is recommended for better development of DR. In general, this residue has an inhibitory effect on the initial growth of the papaya tree and is not recommended for the production of seedlings of this species
Effects of different levels of irrigation suppression and fertigation on potato yield
Get PDFWith the limitation in the availability of water for agriculture and the high costs of fertilizers, it is necessary to adopt strategies for water and nutritional management of agricultural crops. The objective of this study was to evaluate the morphological and physiological characteristics and productivity of potato under the influence of suppression of irrigation and fertigation in Jaboticabal, SP, Brazil. The experiment was carried out in randomized blocks, conducted in the field, using a 3 x 2 factorial scheme. Different times of irrigation suppression were studied at 80, 90 and 100 days after planting, along with forms of fertigation, following the rate of crop absorption and equivalent fertigation. The imposition of irrigation suppression at 100 days, linked to fertigation following the rate of crop absorption, showed a positive effect on the aerial fresh mass of the potato variety studied, especially promoting the increase in productivity, which was 47.82 t ha-1, and efficiency in water use, which was 10.53 kg of tubers per cubic meter of water. This observation indicates that the application of fertilizers, in sync with the needs of the crop, can improve the efficiency of water use and increase productivity. These findings highlight the importance of integrated strategies to optimize potato cultivation and make it more resistant to adversity, seeking a more sustainable and productive agriculture.With the limitation in the availability of water for agriculture and the high costs of fertilizers, it is necessary to adopt strategies for water and nutritional management of agricultural crops. The objective of this study was to evaluate the morphological and physiological characteristics and productivity of potato under the influence of suppression of irrigation and fertigation in Jaboticabal, SP, Brazil. The experiment was carried out in randomized blocks, conducted in the field, using a 3 x 2 factorial scheme. Different times of irrigation suppression were studied at 80, 90 and 100 days after planting, along with forms of fertigation, following the rate of crop absorption and equivalent fertigation. The imposition of irrigation suppression at 100 days, linked to fertigation following the rate of crop absorption, showed a positive effect on the aerial fresh mass of the potato variety studied, especially promoting the increase in productivity, which was 47.82 t ha-1, and efficiency in water use, which was 10.53 kg of tubers per cubic meter of water. This observation indicates that the application of fertilizers, in sync with the needs of the crop, can improve the efficiency of water use and increase productivity. These findings highlight the importance of integrated strategies to optimize potato cultivation and make it more resistant to adversity, seeking a more sustainable and productive agriculture
Genetic parameters and selection gains in open-pollination progenies of bacabi palm tree (Oenocarpus mapora): Genetic parameters and selection gains in open-pollination progenies of bacabi palm tree (Oenocarpus mapora)
No full textThe Bacabi (Oenocarpus mapora Karsten) is an Amazonian palm whose fruit is widely used in the food industry due to its organoleptic properties and excellent nutritional quality. The objective of this work was to estimate genetic parameters and selection gains in the selection of open pollinated bacabi progenies. The experiment was carried out in the district of Campo Limpo, in the municipality of Santo Antônio do Tauá, state of Pará. The study assessed 38 progenies from open‑pollination under an agroforestry system in a randomized block design with five replicates and two plants per plot. At Seventeen, Twenty-four and Thirty months after planting, data were collected on the following traits: stem height (SH), plant diameter (DIAM), number of live leaves (NLL), length of the leaf rachis (LLR), number of leaflet pairs (NLP) and leaflet length (LL). Genetic variety was observed among and within progenies for all evaluated traits. The broad‑sense heritability estimates varied between 0.13 and 72.81%. High values were found for NLP (72.81%), DIAM (52.01%), LLR (62.64%), and SH (66.16%). Selection gains can be achieved for all the traits evaluated, with selection of 30% among progenies and 20% inside progenies.The Bacabi (Oenocarpus mapora Karsten) is an Amazonian palm whose fruit is widely used in the food industry due to its organoleptic properties and excellent nutritional quality. The objective of this work was to estimate genetic parameters and selection gains in the selection of open pollinated bacabi progenies. The experiment was carried out in the district of Campo Limpo, in the municipality of Santo Antônio do Tauá, state of Pará. The study assessed 38 progenies from open‑pollination under an agroforestry system in a randomized block design with five replicates and two plants per plot. At Seventeen, Twenty-four and Thirty months after planting, data were collected on the following traits: stem height (SH), plant diameter (DIAM), number of live leaves (NLL), length of the leaf rachis (LLR), number of leaflet pairs (NLP) and leaflet length (LL). Genetic variety was observed among and within progenies for all evaluated traits. The broad‑sense heritability estimates varied between 0.13 and 72.81%. High values were found for NLP (72.81%), DIAM (52.01%), LLR (62.64%), and SH (66.16%). Selection gains can be achieved for all the traits evaluated, with selection of 30% among progenies and 20% inside progenies
Pre-harvest application of 2-(3-chlorophenoxy) propionic acid on pineapple plants
Get PDFThe application of plant regulators such as exogenous auxin may provide effects on the translocation of carbohydrates to plant sinks, which may result in larger parthenocarpic fruits. The objective of the study was to evaluate the effects of the application of 2-(3-chlorophenoxy) propionic acid on the growth and quality of pineapple fruits. The experiment was carried out in a randomized block design. After floral induction, 2-(3-chlorophenoxy) propionic acid (CPA) was applied directly on the inflorescences at the following doses: 0 mg L-1; 40.0 mg L-1; 80.0 mg L-1; 120.0 mg L-1 and 160.0 mg L-1. Growth evaluations continued until 84 days after application, measuring fruit length (cm) with and without crown, crown length (cm), leaf D dry matter, fruit weight with and without crown (g), calculating if also, the absolute and relative growth rates. The post-harvest and quality characteristics of the fruits were also evaluated, as well as the harvest index. The application of CPA significantly reduces the length and weight of the crown of the fruits, however, the exogenous application of auxin provided an increase in the weight of the fruit. Regarding the post-harvest analysis, the application of CPA reduced the content of soluble solids in the fruit pulp.The application of plant regulators such as exogenous auxin may provide effects on the translocation of carbohydrates to plant sinks, which may result in larger parthenocarpic fruits. The objective of the study was to evaluate the effects of the application of 2-(3-chlorophenoxy) propionic acid on the growth and quality of pineapple fruits. The experiment was carried out in a randomized block design. After floral induction, 2-(3-chlorophenoxy) propionic acid (CPA) was applied directly on the inflorescences at the following doses: 0 mg L-1; 40.0 mg L-1; 80.0 mg L-1; 120.0 mg L-1 and 160.0 mg L-1. Growth evaluations continued until 84 days after application, measuring fruit length (cm) with and without crown, crown length (cm), leaf D dry matter, fruit weight with and without crown (g), calculating if also, the absolute and relative growth rates. The post-harvest and quality characteristics of the fruits were also evaluated, as well as the harvest index. The application of CPA significantly reduces the length and weight of the crown of the fruits, however, the exogenous application of auxin provided an increase in the weight of the fruit. Regarding the post-harvest analysis, the application of CPA reduced the content of soluble solids in the fruit pulp
Estimating tomato production losses due to plant viruses, a look at the past and new challenges
Get PDFThis review analyzes the available technical and scientific reports addressing tomato crop losses and discusses the ponderable characteristics for estimating losses caused by Tomato Infecting-Viruses. The tomato around the world represents an important economic aspect, it has positioned as a crop that contributes to the gross domestic product and is essential to achieve food security in some regions. Viral diseases are one of the main causes of economic losses and tomato production, due to the easy dissemination of viral particles, difficult detection, and the few options to combat virus diseases. Tomato Infecting-Viruses such as ToBRFV, TLYCV, TSWV, and TMV are some of the most important viruses due to their ability to cause losses. Abiotic factors must be considered to estimate losses with greater precision and biotic factors, restricted mainly to insects, have an important role in the virus dispersion and adaptation to new niches not studied yet. Viral infections in tomato crops can reach 100% and reported losses are between 2 and 10%. There are no recent official statistics on economic losses due to tomato viruses, the main limitation is to extrapolate and accurately predict today\u27s losses with data from the past decade. The main challenges for estimating the economic impact of viral diseases in tomato crops lie in the omission by growers and authorities on the presence of viral symptoms and the product value in the market. Considering the absolute value of tomato cultivation economic losses by virus diseases should be around 2 to 5% annually.This review analyzes the available technical and scientific reports addressing tomato crop losses and discusses the ponderable characteristics for estimating losses caused by Tomato Infecting-Viruses. The tomato around the world represents an important economic aspect, it has positioned as a crop that contributes to the gross domestic product and is essential to achieve food security in some regions. Viral diseases are one of the main causes of economic losses and tomato production, due to the easy dissemination of viral particles, difficult detection, and the few options to combat virus diseases. Tomato Infecting-Viruses such as ToBRFV, TLYCV, TSWV, and TMV are some of the most important viruses due to their ability to cause losses. Abiotic factors must be considered to estimate losses with greater precision and biotic factors, restricted mainly to insects, have an important role in the virus dispersion and adaptation to new niches not studied yet. Viral infections in tomato crops can reach 100% and reported losses are between 2 and 10%. There are no recent official statistics on economic losses due to tomato viruses, the main limitation is to extrapolate and accurately predict today\u27s losses with data from the past decade. The main challenges for estimating the economic impact of viral diseases in tomato crops lie in the omission by growers and authorities on the presence of viral symptoms and the product value in the market. Considering the absolute value of tomato cultivation economic losses by virus diseases should be around 2 to 5% annually
Physiology and development of grafted dwarf cashew seedlings under different fertilization doses and irrigated with saline water
Get PDFSalinity is one of the primary challenges faced by irrigated agriculture in semi-arid regions. This study aimed to investigate the effects of fertilization on the development of cashew seedlings irrigated with water of varying salinity levels. The research was conducted in a protected environment at Embrapa Agroindústria Tropical, Fortaleza, using grafted seedlings of the BRS 189 clone on CCP 06 rootstock. The treatments resulted from the combination of three levels of NPK fertilization (control - without fertilization, 50% less than conventional nutrition, and 100% of conventional nutrition used by the crop), which was incorporated into the substrate before sowing CCP 06, with four salinity levels (ECa of 0.8, 4.0, 7.0, and 10.0 dS m-1) of the irrigation water for the seedlings. Gas exchange, assimilate accumulation, growth, and nutrient content in the leaves, stems, and roots of the seedlings were evaluated 90 days after grafting. The data were subjected to analysis of variance, and when a significant effect was observed, the Tukey test was performed, while quantitative data were subjected to regression analysis. Overall, fertilization levels did not influence seedling growth. Fertilization did not interfere with photosynthate production, which performed better when the seedlings were subjected to a salinity of 7.0 dS m-1. The application of NPK to the substrate resulted in higher levels of nitrogen in the leaves, while phosphorus content decreased, and foliar potassium was not influenced by fertilization.Salinity is one of the primary challenges faced by irrigated agriculture in semi-arid regions. This study aimed to investigate the effects of fertilization on the development of cashew seedlings irrigated with water of varying salinity levels. The research was conducted in a protected environment at Embrapa Agroindústria Tropical, Fortaleza, using grafted seedlings of the BRS 189 clone on CCP 06 rootstock. The treatments resulted from the combination of three levels of NPK fertilization (control - without fertilization, 50% less than conventional nutrition, and 100% of conventional nutrition used by the crop), which was incorporated into the substrate before sowing CCP 06, with four salinity levels (ECa of 0.8, 4.0, 7.0, and 10.0 dS m-1) of the irrigation water for the seedlings. Gas exchange, assimilate accumulation, growth, and nutrient content in the leaves, stems, and roots of the seedlings were evaluated 90 days after grafting. The data were subjected to analysis of variance, and when a significant effect was observed, the Tukey test was performed, while quantitative data were subjected to regression analysis. Overall, fertilization levels did not influence seedling growth. Fertilization did not interfere with photosynthate production, which performed better when the seedlings were subjected to a salinity of 7.0 dS m-1. The application of NPK to the substrate resulted in higher levels of nitrogen in the leaves, while phosphorus content decreased, and foliar potassium was not influenced by fertilization
Detection Of Sm Gene Resistance To Gray Leaf Spot In (Stemphylium Spp.) Tomato Cultivars Iraq
Get PDFAbstract
Gray leaf spot, Occurs due to Stemphylium spp., is a foliar disease in tomato. The Resistance against gray leaf spot disease is conferred by a single incompletely dominant gene Sm located on chromosome 11. This study aimed to identify cultivar resistant alleles or susceptible alleles by molecular marker tightly linked to the Sm gene and the use of marker-assisted selection inbreeding. In this study, we used eight tomato cultivars Farmed in Iraq. The analysis demonstrated that the co-dominant marker Sm-InDel, which produced 122-bp fragment for resistance in seven genotypes and a 140-bp fragment for susceptible alleles in one genotype, respectively could be utilized in Marker-assisted selection (MAS)for gray leaf spot resistance.Gray leaf spot, Occurs due to Stemphylium spp., is a foliar disease in tomato. The Resistance against gray leaf spot disease is conferred by a single incompletely dominant gene Sm located on chromosome 11. This study aimed to identify cultivar resistant alleles or susceptible alleles by molecular marker tightly linked to the Sm gene and the use of marker-assisted selection inbreeding. In this study, we used eight tomato cultivars Farmed in Iraq. The analysis demonstrated that the co-dominant marker Sm-InDel, which produced 122-bp fragment for resistance in seven genotypes and a 140-bp fragment for susceptible alleles in one genotype, respectively could be utilized in Marker-assisted selection (MAS)for gray leaf spot resistance
Melon cultivation under agrotextile increases production and reduces phytosanitary products
Get PDFAbiotic and biotic factors influence the productivity and quality of melon fruit; therefore, the protection of plants using agrotextile mesh is a solution that can be agronomically viable, as it reduces the use phytosanitary pesticides and allows for greater productivity and, consequently, quality. The objective this study was to evaluate the influence of coverage time with an agrotextile (0, 21, 26 and 31 days after transplanting (DAT)) in melon hybrids ‘Gold Mine’, ‘Soleares’, ‘Lual’ and ‘Natal’ on productivity and fruit quality attributes. The plants that were protected with agrotextile mesh for 21 and 26 DAT had higher productivity (53.5 and 52.1 t ha−1). Among the hybrids, all excellent plots produced above 42.4 1 t ha−1. Of the observed hybrid quality parameters, \u27Natal\u27 protected for 21 DAT showed a better total phenol content and a higher maturation index, and \u27Soleares\u27 protected for 21 DAT showed a higher DPPH antioxidant activity and flavonoid content.Abiotic and biotic factors influence the productivity and quality of melon fruit; therefore, the protection of plants using agrotextile mesh is a solution that can be agronomically viable, as it reduces the use phytosanitary pesticides and allows for greater productivity and, consequently, quality. The objective this study was to evaluate the influence of coverage time with an agrotextile (0, 21, 26 and 31 days after transplanting (DAT)) in melon hybrids ‘Gold Mine’, ‘Soleares’, ‘Lual’ and ‘Natal’ on productivity and fruit quality attributes. The plants that were protected with agrotextile mesh for 21 and 26 DAT had higher productivity (53.5 and 52.1 t ha−1). Among the hybrids, all excellent plots produced above 42.4 1 t ha−1. Of the observed hybrid quality parameters, \u27Natal\u27 protected for 21 DAT showed a better total phenol content and a higher maturation index, and \u27Soleares\u27 protected for 21 DAT showed a higher DPPH antioxidant activity and flavonoid content