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Biocontrol agents against Penicillium digitatum in \u27pera\u27 orange
Get PDFThis work aimed to evaluate the efficiency of biocontrol agents in controlling green mold (Penicillium digitatum) in \u27pera\u27 orange fruits. In vitro experiments were carried out with a fungus isolate grown on BDA medium and tested against different concentrations of commercial products based on biocontrol agents: Trichoderma harzianum (0, 5, 10, 15, 20 and 25 mL L -1 ), Bacillus subtilis (0, 2, 4, 6, 8 and 10 mL L -1 ) and B. licheniformis + B. subtilis + T. longibrachiatum (0, 5, 10, 15, 20 and 25 g L -1 ) and the fungicide imazalil as standard (2 mL L -1 ). The experiment analyzed mycelial growth and spore germination. Based on the results, in vivo tests were carried out, evaluating the curative and preventive effect of applying biocontrol agents as inoculating with 10 µL of conidial suspension (108 conidia mL-1). All biochemical agents displayed 100% control over mycelial growth and a linear effect to inhibit the germination of P. digitatum. The in vivo tests highlighted that all agents showed a linear effect, both in the curative and preventive effects, significantly reducing the development of green mold (AUDPC) in \u27pera\u27 orange fruits. The experiment concludes that the prophylactic application of 25 mL L -1 of T. harzianum, 10 mL L -1 of B. subtilis, and 25 g L -1 of B. licheniformis + B. subtilis + T. longibrachiatum in orange fruits \u27pera\u27 control P. digitatum.This work aimed to evaluate the efficiency of biocontrol agents in controlling green mold (Penicillium digitatum) in \u27pera\u27 orange fruits. In vitro experiments were carried out with a fungus isolate grown on BDA medium and tested against different concentrations of commercial products based on biocontrol agents: Trichoderma harzianum (0, 5, 10, 15, 20 and 25 mL L -1 ), Bacillus subtilis (0, 2, 4, 6, 8 and 10 mL L -1 ) and B. licheniformis + B. subtilis + T. longibrachiatum (0, 5, 10, 15, 20 and 25 g L -1 ) and the fungicide imazalil as standard (2 mL L -1 ). The experiment analyzed mycelial growth and spore germination. Based on the results, in vivo tests were carried out, evaluating the curative and preventive effect of applying biocontrol agents as inoculating with 10 µL of conidial suspension (108 conidia mL-1). All biochemical agents displayed 100% control over mycelial growth and a linear effect to inhibit the germination of P. digitatum. The in vivo tests highlighted that all agents showed a linear effect, both in the curative and preventive effects, significantly reducing the development of green mold (AUDPC) in \u27pera\u27 orange fruits. The experiment concludes that the prophylactic application of 25 mL L -1 of T. harzianum, 10 mL L -1 of B. subtilis, and 25 g L -1 of B. licheniformis + B. subtilis + T. longibrachiatum in orange fruits \u27pera\u27 control P. digitatum
Morpho-physiological responses of potato cultivars under weed competition
Get PDFAmong the factors that affect potato productivity, the interference caused by weeds stands out as they may compete with the crop, release allelopathic substances to soil and host insects and diseases. Therefore, the objective of this work was to assess the competitive ability of white (Aghata) and pink (Asterix) potato cultivars when infested by Alexandergrass (Urochloa plantaginea) or wild poinsettia (Euphorbia heteroplylla). The experiment was carried out into greenhouse in randomized blocks design, with four replications. A single potato plant faced competition by either Alexandergrass or wild poinsettia, ranging from 0 to 64 plants per plot. Fifty days after seedling transplanting, variables related to the morphophysiology of potato cultivars and weeds were assessed. Potatoes have low competitive ability with both weed species, with wild poinsettia being the most aggressive in reducing the accumulation rates of leaf area and aboveground dry mass. Potato photosynthetic rate is negatively influenced by the presence of both weeds. Internal CO2 concentration, stomatal conductance, carboxylation efficiency and transpiration rates of potato varied depending on weed species and density. Morphological parameters are reduced when potato competed with Alexandergrass or wild poinsettia; however the physiological parameters are most sharply affected when under competition with wild poinsettia.Among the factors that affect potato productivity, the interference caused by weeds stands out as they may compete with the crop, release allelopathic substances to soil and host insects and diseases. Therefore, the objective of this work was to assess the competitive ability of white (Aghata) and pink (Asterix) potato cultivars when infested by Alexandergrass (Urochloa plantaginea) or wild poinsettia (Euphorbia heteroplylla). The experiment was carried out into greenhouse in randomized blocks design, with four replications. A single potato plant faced competition by either Alexandergrass or wild poinsettia, ranging from 0 to 64 plants per plot. Fifty days after seedling transplanting, variables related to the morphophysiology of potato cultivars and weeds were assessed. Potatoes have low competitive ability with both weed species, with wild poinsettia being the most aggressive in reducing the accumulation rates of leaf area and aboveground dry mass. Potato photosynthetic rate is negatively influenced by the presence of both weeds. Internal CO2 concentration, stomatal conductance, carboxylation efficiency and transpiration rates of potato varied depending on weed species and density. Morphological parameters are reduced when potato competed with Alexandergrass or wild poinsettia; however the physiological parameters are most sharply affected when under competition with wild poinsettia
Morphophysiology of Punica Granatum L. under microalgae biomass stimulation
Get PDFThe use of microalgae has been proeminent in agricultural scenario, because it is an alternative product considered extremelly productive, which contains essential elements for plants. Thus, this study aimed to evaluate the morphophysiology of Punica granatum L. seedlings treated with Spirulina platensis and Scenedesmus sp. nanoparticles in controlled environment. The research was carried out at the of Federal University of Campina Grande, Pombal-PB, using a completely randomized design with five replications. The factorial scheme (2 x 4) was adopted, represented by two types of microalgae (Spirulina platensis; Scenedesmus sp.) and four doses of application (0, 5, 10 and 15%). Growth evaluations happened at 135 days after planting, verifying the number of leaves and branches and shoot length. The physiological parameters evaluated were gas exchanges, chlorophyll ‘a’ fluorescence, electron transport rate, stationary fluorescence, maximum fluorescence yield after light adaptation and quantum efficiency of PSII. Shoot length and number of branches had rises at doses of 6 and 15%. Number of leaves was induced in seedlings at dose of 8% with Spirulina platensis. Stomatal conductance and internal CO2 concentration increased in seedlings sprayed with Spirulina platensis. extract of Scenedesmus sp. improved the stationary fluorescence and quantum efficiency of PSII in pomegranate seedlings.The use of microalgae has been proeminent in agricultural scenario, because it is an alternative product considered extremelly productive, which contains essential elements for plants. Thus, this study aimed to evaluate the morphophysiology of Punica granatum L. seedlings treated with Spirulina platensis and Scenedesmus sp. nanoparticles in controlled environment. The research was carried out at the of Federal University of Campina Grande, Pombal-PB, using a completely randomized design with five replications. The factorial scheme (2 x 4) was adopted, represented by two types of microalgae (Spirulina platensis; Scenedesmus sp.) and four doses of application (0, 5, 10 and 15%). Growth evaluations happened at 135 days after planting, verifying the number of leaves and branches and shoot length. The physiological parameters evaluated were gas exchanges, chlorophyll ‘a’ fluorescence, electron transport rate, stationary fluorescence, maximum fluorescence yield after light adaptation and quantum efficiency of PSII. Shoot length and number of branches had rises at doses of 6 and 15%. Number of leaves was induced in seedlings at dose of 8% with Spirulina platensis. Stomatal conductance and internal CO2 concentration increased in seedlings sprayed with Spirulina platensis. extract of Scenedesmus sp. improved the stationary fluorescence and quantum efficiency of PSII in pomegranate seedlings
Transformation of dolomite powder into value added fertilizer and its effect on growth and yield of tomato plant
Get PDFIn Dolomite industry, various purposes have led to the generation of large amount of dolomite powder during mechanical processing. Dolomite is a rich source of Ca and Mg and XRF analysis showed the presence of certain micro and ultra micro plant nutrients in it. In the raw form these nutrients are not in easily plant accessible form. In the present research, dolomite powder was converted into easily plant accessible form and its value-added fertilizer is formed by mixing vermicompost with chemically converted dolomite powder. Three types of experiments- control (simple soil), control with compost (soil + vermicompost), and different percentages [X, 2X, 3X, 4X & 5X (X= 3%)] of value-added fertilizer with soil were performed on growth and yield of tomato plant. It was found that among all treatments, 5X showed maximum plant growth, crop yield with increased biomass.In Dolomite industry, various purposes have led to the generation of large amount of dolomite powder during mechanical processing. Dolomite is a rich source of Ca and Mg and XRF analysis showed the presence of certain micro and ultra micro plant nutrients in it. In the raw form these nutrients are not in easily plant accessible form. In the present research, dolomite powder was converted into easily plant accessible form and its value-added fertilizer is formed by mixing vermicompost with chemically converted dolomite powder. Three types of experiments- control (simple soil), control with compost (soil + vermicompost), and different percentages [X, 2X, 3X, 4X & 5X (X= 3%)] of value-added fertilizer with soil were performed on growth and yield of tomato plant. It was found that among all treatments, 5X showed maximum plant growth, crop yield with increased biomass
Potential of entomopathogenic fungi to control insect pests and disease at lettuce and arugula crops
Get PDFThe lettuce (Lactuca sativa L.) (Asteraceae) and arugula (Eruca sativa Miller) (Brassicaceae) crops are attacked by various pests and diseases, but the control is usually done with agrochemicals. We evaluate the control of pests and diseases by systematic applications of the entomopathogenic fungi strains Metarhizium anisopliae IBCB425 and Beauveria bassiana IBCB66 both 300g c.p. in the planting groove and 200 g c.p. ha-1 on the foliage, in weekly applications at lettuce and arugula crops planted in association. For the evaluation of pests and diseases, 15 plants were evaluated at random in three beds per treatment. In the lettuce crop occurred the presence of aphids (Myzus persicae Hemiptera:Aphididae), whiteflies (Bemisia tabaci Hemiptera: Aleyrodidae), thrips (Frankliniella schultzei Thysanoptera:Thripidae), leafhoppers Agallia albidula (Hemiptera: Cicadellidae) and septoria disease (Septoria lactucae). In the arugula crop the same pests occurred, but with any disease. The fungi B. bassiana and M. anisopliae controlled F. schultzei and S. lactucae at lettuce crop, B. tabaci in both crops, but did not control M. persicae and A. albidula in both crops. The fungus B. bassiana decreased the mean number of leaves per plant and the mean of dry mass weight of arugula plants in relation to the control treatment, but the sample size may have interfered with these results. The two fungi could be used as biological control agents of pests and diseases at lettuce and arugula crops, especially in organic farming
Flowering and production of Palmer mango trees under organic compound and paclobutrazol application
Get PDFThe objective of this work was to evaluate the effects of applications of humified organic compound rates combined with paclobutrazol (PBZ) rates on the flowering, production, and fruit quality of Palmer mango trees grown in two production seasons (Seasons 1 and 2). Two experiments were conducted in different production seasons and areas in Matias Cardoso, MG, Brazil. A randomized block experimental design with four replications was used, in a 4×2+1 factorial arrangement, consisted of 4 humidified organic compound rates (10, 15, 20, and 25 mL plant-1), 2 PBZ rates (0.7 and 0.85 g per meter of canopy diameter), and a control (application of PBZ at 0.85 g per meter of canopy diameter). Vegetative, physiological, reproductive, production, and post-harvest fruit quality characteristics were evaluated. The data were subjected to analysis of variance and regression or mean tests. The treatments had significant effects on some characteristics in Season 1. Plants treated with the organic compound combined with PBZ had higher chlorophyll contents than those in the control. The increase in the organic compound rate linearly increased the total number of flowers and number of male flowers per axillary panicle, but decreased soluble solids content. The application of the lowest PBZ rate resulted in higher soluble solids content and titratable acidity in mango fruits. The treatments did not affect the evaluated characteristics in Season 2. The application of humidified organic compound combined with paclobutrazol showed no benefits for the management of floral induction in Palmer mango trees.The objective of this work was to evaluate the effects of applications of humified organic compound rates combined with paclobutrazol (PBZ) rates on the flowering, production, and fruit quality of Palmer mango trees grown in two production seasons (Seasons 1 and 2). Two experiments were conducted in different production seasons and areas in Matias Cardoso, MG, Brazil. A randomized block experimental design with four replications was used, in a 4×2+1 factorial arrangement, consisted of 4 humidified organic compound rates (10, 15, 20, and 25 mL plant-1), 2 PBZ rates (0.7 and 0.85 g per meter of canopy diameter), and a control (application of PBZ at 0.85 g per meter of canopy diameter). Vegetative, physiological, reproductive, production, and post-harvest fruit quality characteristics were evaluated. The data were subjected to analysis of variance and regression or mean tests. The treatments had significant effects on some characteristics in Season 1. Plants treated with the organic compound combined with PBZ had higher chlorophyll contents than those in the control. The increase in the organic compound rate linearly increased the total number of flowers and number of male flowers per axillary panicle, but decreased soluble solids content. The application of the lowest PBZ rate resulted in higher soluble solids content and titratable acidity in mango fruits. The treatments did not affect the evaluated characteristics in Season 2. The application of humidified organic compound combined with paclobutrazol showed no benefits for the management of floral induction in Palmer mango trees
Microalga as biofertilizer improves yield, sugars and amino acids content in red beets
Get PDFThe growing uncertainty of future changes in our global climate may pose a threat to some traditional farming methods, stimulating the development of nature friendly technologies. Microalgae are a group of micro photosynthetic organisms, which have immense potential as a renewable and ecofriendly bioresource for various industries. The present study was developed to evaluate foliar sprays of a green microalga Asterarcys quadricellulare (CCAP 294/1) on organically grown red beets (Beta vulgaris L) A field experiment was implemented to evaluate microalgal biomass bioactivity and its effects in leaves and hypocotyl growth, comparing fresh and dry weight, yield; and biochemical alterations, comparing pigments, sugars and free amino acids. The spray dried biomass of the A. quadricellulare was applied to leaves at concentrations 0.05g, 0.1 g, 0.15g and 0.25 g L-¹. The sprays with the microalga biomass increased yield, and improved free amino acids, sugars, dry weight and beets commercial diameter. This study shows that the foliar sprays presented a biofertilizer effect, emphasizing the solution at 0.25 g L-¹, which resulted in a 52% increase in yield. The results indicate that the microalga is a nature friendly, renewable and economic resource for red beet production.The growing uncertainty of future changes in our global climate may pose a threat to some traditional farming methods, stimulating the development of nature friendly technologies. Microalgae are a group of micro photosynthetic organisms, which have immense potential as a renewable and ecofriendly bioresource for various industries. The present study was developed to evaluate foliar sprays of a green microalga Asterarcys quadricellulare (CCAP 294/1) on organically grown red beets (Beta vulgaris L) A field experiment was implemented to evaluate microalgal biomass bioactivity and its effects in leaves and hypocotyl growth, comparing fresh and dry weight, yield; and biochemical alterations, comparing pigments, sugars and free amino acids. The spray dried biomass of the A. quadricellulare was applied to leaves at concentrations 0.05g, 0.1 g, 0.15g and 0.25 g L-¹. The sprays with the microalga biomass increased yield, and improved free amino acids, sugars, dry weight and beets commercial diameter. This study shows that the foliar sprays presented a biofertilizer effect, emphasizing the solution at 0.25 g L-¹, which resulted in a 52% increase in yield. The results indicate that the microalga is a nature friendly, renewable and economic resource for red beet production
Growth analysis of six lisianthus (Eustoma grandiflorum) cultivars in different growing seasons
Get PDFThe objective of work was to evaluate the growth of six lisianthus cultivars at different times, in a protected environment, in the southern region of Brazil. The experimental design was randomized blocks, in split plots, with three replications. The plots were constituted by the lisianthus cultivars: \u27White Excalibur\u27, \u27Blue Picotee\u27, \u27Blue Echo\u27, \u27Arena Red\u27, \u27Robella\u27 and \u27Echo Champagne\u27and the subplots by the dates of plant collections (evaluations), which were carried out at the time of transplantation (0) and 21, 42, 63 and 84 days after transplantation (DAT) for seasons 1(October 2017 to January 2018), 2 (November 2017 to February 2018) and 5 (August to December 2018); and at (0) and at 30, 60, 90, 120, 150 and 180 DAT at seasons 3 (April to November 2018), 4 (July to December 2018) and 6 (February to June 2019). All cultivars showed an increasing tendency to accumulate a dry mass of the plants until the harvest of the floral stems. The maximum dry mass value was obtained by the cultivar \u27Robella\u27 (20.3 g/plant-1) in season 3. For all cultivars, the absolute and relative growth rates of the crop increased with the advancement of the cultivation period. In seasons 1, 2 and 5 all cultivars showed higher growth velocities between 63 and 84 days after transplanting (DAT). In seasons 3 and 4 the cultivars showed higher growth from 90 to 150 DAT. In seasons 1 and 2 the cultivars showed a higher rate of plant growth, resulting in a shortening of the cycle. The cultivars conducted in seasons 3 and 4 had a longer cultivation time due to the autumn/winter period. The cultivar \u27Arena Red\u27 showed the lowest growth rates in all seasons
Bioinsecticides based on neem (Azadirachta indica) and rue (Ruta graveolens) against Agrotis ipsilon
Get PDFAgrotis ipsilon is an important pest of several crops, where it causes damage to various parts of the plant such as stems, roots, leaves and tubers. Due to the growing demand for controlling these pests, there is a constant need for new products as the organisms acquire resistance after continuous contact. And this also generates a demand for bioinsecticides, which normally pose a lower health risk and are less harmful to the environment. Among the plants commonly used as insecticides are neem and rue, which have already been studied for several pests, although never together. This work aimed to determine the insecticidal activity of a natural insecticide derived from a mixture of neem and rue, commonly used in the region of Senhor do Bonfim-BA against A. ipsilon. Four different solutions were prepared, containing a) 20 neem leaves, 10 rue leaves and 5 A. ipsilon caterpillars, b) 20 neem leaves and 10 rue leaves, c) 20 neem leaves and d) 10 rue leaves. Water was tested as control. In the tests carried out, both the mixture popularly used in the region, containing neem, rue, and A. ipsilon caterpillars, as well as the solution containing only neem and rue had good results, killing all caterpillars in 72 hours. Isolated plant extracts did not obtain good results, only delaying the formation of pupae for neem extracts. Therefore, the mixture of Neem and Rue showed good insecticidal potential against A. ipsilon, with much higher activity than its isolated components.Agrotis ipsilon is an important pest of several crops, where it causes damage to various parts of the plant such as stems, roots, leaves and tubers. Due to the growing demand for controlling these pests, there is a constant need for new products as the organisms acquire resistance after continuous contact. And this also generates a demand for bioinsecticides, which normally pose a lower health risk and are less harmful to the environment. Among the plants commonly used as insecticides are neem and rue, which have already been studied for several pests, although never together. This work aimed to determine the insecticidal activity of a natural insecticide derived from a mixture of neem and rue, commonly used in the region of Senhor do Bonfim-BA against A. ipsilon. Four different solutions were prepared, containing a) 20 neem leaves, 10 rue leaves and 5 A. ipsilon caterpillars, b) 20 neem leaves and 10 rue leaves, c) 20 neem leaves and d) 10 rue leaves. Water was tested as control. In the tests carried out, both the mixture popularly used in the region, containing neem, rue, and A. ipsilon caterpillars, as well as the solution containing only neem and rue had good results, killing all caterpillars in 72 hours. Isolated plant extracts did not obtain good results, only delaying the formation of pupae for neem extracts. Therefore, the mixture of Neem and Rue showed good insecticidal potential against A. ipsilon, with much higher activity than its isolated components
Tomato growth submitted to different soil water conditions using biostimulants
Get PDFStress caused by water deficit is the main factor that decreases the productivity and quality of agricultural products. The objective of this study was to describe the morphological components of tomato plants subjected to different soil water conditions, as well as elucidate the use of the Seed+ and Crop+ biostimulants as an alternative to mitigate the effects of water deficit. The experiment was conducted in a completely randomized design with 12 treatments: control; Seed+; Seed+ + Crop+ 1x; Seed+ + Crop+ 2x; Crop+ 1x; Crop+ 2x, in soil water conditions at 50% and 100% soil water retention capacity (WRC). The plant height, leaf width and length, and stem diameter variables referring to the plants were assessed under both soil water conditions and by applying biostimulants. Data were organized and adjusted to the non-linear logistic regression model in order to describe the growth of tomato plants of the Santa Cruz Kada cultivar, which proved to be adequate to describe the growth and showed the best fit; in addition, the use of the Seed+ and Crop+ biostimulants helped in the morphology of tomato plants in both water conditions and reduced the damages caused by water deficit.Stress caused by water deficit is the main factor that decreases the productivity and quality of agricultural products. The objective of this study was to describe the morphological components of tomato plants subjected to different soil water conditions, as well as elucidate the use of the Seed+ and Crop+ biostimulants as an alternative to mitigate the effects of water deficit. The experiment was conducted in a completely randomized design with 12 treatments: control; Seed+; Seed+ + Crop+ 1x; Seed+ + Crop+ 2x; Crop+ 1x; Crop+ 2x, in soil water conditions at 50% and 100% soil water retention capacity (WRC). The plant height, leaf width and length, and stem diameter variables referring to the plants were assessed under both soil water conditions and by applying biostimulants. Data were organized and adjusted to the non-linear logistic regression model in order to describe the growth of tomato plants of the Santa Cruz Kada cultivar, which proved to be adequate to describe the growth and showed the best fit; in addition, the use of the Seed+ and Crop+ biostimulants helped in the morphology of tomato plants in both water conditions and reduced the damages caused by water deficit