Pub Date : 2022-05-24DOI: 10.4025/actasciagron.v44i1.55277
Roxane do Carmo Lemos, Getúlio Ferreira Caixeta, R. H. D. Silva, A. F. B. Abreu, M. A. P. Ramalho
In Brazil, there is an increasing demand for common bean (Phaseolus vulgaris L.) cultivars having Carioca-type (cream-colored seed coat with brown stripes) beans which have a light color that persists for a longer time combined with the most possible upright plant architecture. However, plant breeders are finding it difficult to combine these two traits in the same cultivar. The aim of this study was to compare success in the selection of new common bean lines that combine the two traits in segregating populations with 25%, 50%, or 75% of the alleles from the parents contrasting in upright plant architecture or in bean grains with persistent light color. A biparental cross was performed between a parent with light-colored beans (P1) and another with upright plants (P2). Three populations were obtained from the F1 seeds, with allelic frequencies of 75%, 50%, and 25% of P1. Subsequently, progenies were evaluated in a similar number in each population in the F2:3, F2:4, F2:5, and F2:6 generations. The plant architecture (PA) and grain darkening (GD) traits were visually evaluated using a scoring scale. Genetic and phenotypic parameters were estimated for all generations. There was no expressive advantage in using populations with a greater allele proportion of the parent favorable to upright plant architecture or slow grain darkening either in releasing of variability or in the occurrence of progenies with favorable phenotypes for the two traits.
{"title":"Alternatives for selection of carioca common bean lines that combine upright plants and slow grain darkening","authors":"Roxane do Carmo Lemos, Getúlio Ferreira Caixeta, R. H. D. Silva, A. F. B. Abreu, M. A. P. Ramalho","doi":"10.4025/actasciagron.v44i1.55277","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.55277","url":null,"abstract":"In Brazil, there is an increasing demand for common bean (Phaseolus vulgaris L.) cultivars having Carioca-type (cream-colored seed coat with brown stripes) beans which have a light color that persists for a longer time combined with the most possible upright plant architecture. However, plant breeders are finding it difficult to combine these two traits in the same cultivar. The aim of this study was to compare success in the selection of new common bean lines that combine the two traits in segregating populations with 25%, 50%, or 75% of the alleles from the parents contrasting in upright plant architecture or in bean grains with persistent light color. A biparental cross was performed between a parent with light-colored beans (P1) and another with upright plants (P2). Three populations were obtained from the F1 seeds, with allelic frequencies of 75%, 50%, and 25% of P1. Subsequently, progenies were evaluated in a similar number in each population in the F2:3, F2:4, F2:5, and F2:6 generations. The plant architecture (PA) and grain darkening (GD) traits were visually evaluated using a scoring scale. Genetic and phenotypic parameters were estimated for all generations. There was no expressive advantage in using populations with a greater allele proportion of the parent favorable to upright plant architecture or slow grain darkening either in releasing of variability or in the occurrence of progenies with favorable phenotypes for the two traits.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"49 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90719604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.4025/actasciagron.v44i1.55426
A. M. Pereira, E. Picoli, K. Petrucci, M. P. Gomes, R. R. P. Cruz, Luciana Gomes Soares, D. N. Gonçalves, F. Finger
Excoriation damage is among the major causes of postharvest potato losses. Curing is known to increase the resistance of tubers to excoriation injury, with the temperature influencing the traumatic phellogen and periderm regeneration, as well as tuber processing quality. This study aimed to evaluate the effects of excoriation procedure and curing temperature on the industrial quality, histological characteristics, carbohydrate metabolism, and oxidative enzyme activity of potato tuber. Tubers with or without excoriation were cured at 8, 14, and 20°C for 15 days. Excoriation did not influence the levels of reducing sugars (RS), as well as polyphenoloxidase (PPO) and peroxidase (POD) activities. The concentrations of total soluble sugars (TSS) and non-reducing sugars (NRS) were higher in injured tubers, while reduction in curing temperature increased the concentrations of TSS, NRS, and RS. However, the sugar content was adequate as per the criteria of the pre-fried potato industry and potatoes classified in category 2 (USDA/fast-food industry color grading). The reduction in curing temperature also increased the activity of POD, despite the activity of PPO remaining unchanged. Formation of a closure layer from the outer parenchyma cells of the tuber that prevents desiccation and death of superficial cells, was observed. This protection was completed with the formation of the damage periderm. Periderm regeneration is faster at higher temperatures, 15 and 20°C, leading to a lower fresh mass loss and no enzymatic or non-enzymatic browning. The excoriation carried out at 14/20oC for 15 days was sufficient for curing, and for maintaining suitable post-fry quality of potatoes.
{"title":"An approach of using different curing temperature based on potato cv. Innovator periderm differentiation, sugar metabolism, and industrial quality","authors":"A. M. Pereira, E. Picoli, K. Petrucci, M. P. Gomes, R. R. P. Cruz, Luciana Gomes Soares, D. N. Gonçalves, F. Finger","doi":"10.4025/actasciagron.v44i1.55426","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.55426","url":null,"abstract":"Excoriation damage is among the major causes of postharvest potato losses. Curing is known to increase the resistance of tubers to excoriation injury, with the temperature influencing the traumatic phellogen and periderm regeneration, as well as tuber processing quality. This study aimed to evaluate the effects of excoriation procedure and curing temperature on the industrial quality, histological characteristics, carbohydrate metabolism, and oxidative enzyme activity of potato tuber. Tubers with or without excoriation were cured at 8, 14, and 20°C for 15 days. Excoriation did not influence the levels of reducing sugars (RS), as well as polyphenoloxidase (PPO) and peroxidase (POD) activities. The concentrations of total soluble sugars (TSS) and non-reducing sugars (NRS) were higher in injured tubers, while reduction in curing temperature increased the concentrations of TSS, NRS, and RS. However, the sugar content was adequate as per the criteria of the pre-fried potato industry and potatoes classified in category 2 (USDA/fast-food industry color grading). The reduction in curing temperature also increased the activity of POD, despite the activity of PPO remaining unchanged. Formation of a closure layer from the outer parenchyma cells of the tuber that prevents desiccation and death of superficial cells, was observed. This protection was completed with the formation of the damage periderm. Periderm regeneration is faster at higher temperatures, 15 and 20°C, leading to a lower fresh mass loss and no enzymatic or non-enzymatic browning. The excoriation carried out at 14/20oC for 15 days was sufficient for curing, and for maintaining suitable post-fry quality of potatoes.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"18 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78537880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.4025/actasciagron.v44i1.54809
D. D. C. Carvalho, T. S. Silva, T. Teófilo, Maria Alice Formiga Porto, Leilson Costa Grangeiro, M. F. Souza, F. D. C. Gonçalves, D. V. Silva
The management of weeds in melon is hindered by the slow initial growth of the crop, favouring weed infestation and reducing production. During the years 2016 and 2017, weed interference periods were evaluated in two melon hybrids, yellow and frog skin, to determine the time of weed control in the crop. Four-parameter logistic regression was used to determine the critical weed control period (CPWC). The weed species with the highest occurrences in 2016 were Merremia aegyptia, Senna obtusifolia, and Urochloa plantaginea. In 2017, there was a predominance of M. aegyptia, indicating the possibility of successive cultivation, favouring the predominance of species with growth habits similar to melons. The increase in the period of living with weeds reduced the productivity and quality of melon fruits. Coexistence with weeds throughout the cycle reduced productivity by about 50%. The CPWC was 15 to 58 and 10 to 45 for frog skin and 12 to 52 and 4 to 50 days for yellow melon in 2016 and 2017, respectively, considering a productivity loss of 5%. These results underscore the importance of adopting strategies that allow melons to grow free from the presence of weeds, especially before they are fully established in the growing area.
{"title":"Weed interference in melon crop under semi-arid conditions","authors":"D. D. C. Carvalho, T. S. Silva, T. Teófilo, Maria Alice Formiga Porto, Leilson Costa Grangeiro, M. F. Souza, F. D. C. Gonçalves, D. V. Silva","doi":"10.4025/actasciagron.v44i1.54809","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54809","url":null,"abstract":"The management of weeds in melon is hindered by the slow initial growth of the crop, favouring weed infestation and reducing production. During the years 2016 and 2017, weed interference periods were evaluated in two melon hybrids, yellow and frog skin, to determine the time of weed control in the crop. Four-parameter logistic regression was used to determine the critical weed control period (CPWC). The weed species with the highest occurrences in 2016 were Merremia aegyptia, Senna obtusifolia, and Urochloa plantaginea. In 2017, there was a predominance of M. aegyptia, indicating the possibility of successive cultivation, favouring the predominance of species with growth habits similar to melons. The increase in the period of living with weeds reduced the productivity and quality of melon fruits. Coexistence with weeds throughout the cycle reduced productivity by about 50%. The CPWC was 15 to 58 and 10 to 45 for frog skin and 12 to 52 and 4 to 50 days for yellow melon in 2016 and 2017, respectively, considering a productivity loss of 5%. These results underscore the importance of adopting strategies that allow melons to grow free from the presence of weeds, especially before they are fully established in the growing area.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"165 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80423473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.4025/actasciagron.v44i1.54952
Talita Vigo Longhi, R. R. Robaina, R. P. Leite Júnior, M. I. Balbi-Peña
Bacterial leaf streak caused by Xanthomonas vasicola pv. vasculorum is an emerging disease for corn production around the world. However, information on management of this disease is still limited. This study aimed to determine the in vitro sensibility of X. vasicola pv. vasculorum to different chemicals and to evaluate the control of bacterial leaf streak on corn under greenhouse conditions. In vitro tests were carried out with kasugamycin, copper sulfate, copper oxychloride, copper hydroxide, cuprous oxide, bioactive copper, mancozeb, chlorothalonil, methyl thiophanate, and tebuconazole at the dosages of 1, 5, 10, 20, 50, 100, 200, and 400 μg mL−1. Four strains of X. vasicola pv. vasculorum were included in the study. The minimal inhibitory concentration for kasugamycin ranged from 50 to 200 μg mL–1, whereas to the inorganic copper compounds varied from 5 to 50 μg mL–1 and to the bioactive copper was 100 μg mL–1. Further, mancozeb and tebuconazole inhibited the bacterial growth at the dosage ranging from 5 to 20 μg mL–1 and 50 to 400 μg mL–1, respectively, depending on the X. vasicola pv. vasculorum strain. Chlorothalonil and methyl thiophanate did not inhibit the growth of the bacterium at any tested concentration. The control of bacterial leaf streak under greenhouse conditions was investigated on corn plants of the cultivar IPR 164 at the V3 phenological vegetative stage, sprayed with kasugamycin (3 mL L–1), copper oxychloride (1.5 mL L–1), bioactive copper (1 mL L–1), mancozeb (2 g L–1), tebuconazole (1 mL L–1), and chlorothalonil (2 mL L–1). The corn plants were inoculated with a 108 CFU mL–1 suspension of the RL1 strain of X. vasicola pv. vasculorum. Only copper oxychloride significantly reduced disease severity. However, this copper compound caused phytotoxicity to the corn plants at the tested concentration.
{"title":"Sensibility of Xanthomonas vasicola pv. vasculorum to chemicals and efficiency of the chemical control of bacterial leaf streak on corn plants","authors":"Talita Vigo Longhi, R. R. Robaina, R. P. Leite Júnior, M. I. Balbi-Peña","doi":"10.4025/actasciagron.v44i1.54952","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54952","url":null,"abstract":"Bacterial leaf streak caused by Xanthomonas vasicola pv. vasculorum is an emerging disease for corn production around the world. However, information on management of this disease is still limited. This study aimed to determine the in vitro sensibility of X. vasicola pv. vasculorum to different chemicals and to evaluate the control of bacterial leaf streak on corn under greenhouse conditions. In vitro tests were carried out with kasugamycin, copper sulfate, copper oxychloride, copper hydroxide, cuprous oxide, bioactive copper, mancozeb, chlorothalonil, methyl thiophanate, and tebuconazole at the dosages of 1, 5, 10, 20, 50, 100, 200, and 400 μg mL−1. Four strains of X. vasicola pv. vasculorum were included in the study. The minimal inhibitory concentration for kasugamycin ranged from 50 to 200 μg mL–1, whereas to the inorganic copper compounds varied from 5 to 50 μg mL–1 and to the bioactive copper was 100 μg mL–1. Further, mancozeb and tebuconazole inhibited the bacterial growth at the dosage ranging from 5 to 20 μg mL–1 and 50 to 400 μg mL–1, respectively, depending on the X. vasicola pv. vasculorum strain. Chlorothalonil and methyl thiophanate did not inhibit the growth of the bacterium at any tested concentration. The control of bacterial leaf streak under greenhouse conditions was investigated on corn plants of the cultivar IPR 164 at the V3 phenological vegetative stage, sprayed with kasugamycin (3 mL L–1), copper oxychloride (1.5 mL L–1), bioactive copper (1 mL L–1), mancozeb (2 g L–1), tebuconazole (1 mL L–1), and chlorothalonil (2 mL L–1). The corn plants were inoculated with a 108 CFU mL–1 suspension of the RL1 strain of X. vasicola pv. vasculorum. Only copper oxychloride significantly reduced disease severity. However, this copper compound caused phytotoxicity to the corn plants at the tested concentration.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"16 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84863312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.4025/actasciagron.v44i1.54787
Ludimila Geiciane de Sá, C. Albuquerque, N. R. Valadares, O. G. Brito, Amara Nunes Mota, A. C. G. Fernandes, A. M. Azevedo
Leaf area is one of the most commonly used physiological parameters in plant growth analysis because it facilitates the interpretation of factors associated with yield. The different leaf formats related to soybean genotypes can influence the quality of the model fit for the estimation of leaf area. Direct leaf area measurement is difficult and inaccurate, requires expensive equipment, and is labor intensive. This study developed methodologies to estimate soybean leaf area using neural networks and considering different leaf shapes. A field experiment was carried out from February to July 2017. Data were collected from thirty-six cultivars separated into three groups according to the leaf shape. Multilayer perceptrons were developed using 300 leaves per group, of which 70% were used for training and 30% for validation. The most important morphological measures were also tested with Garson’s method. The artificial neural networks were efficient in estimating the soybean leaf area, with coefficients of determination close to 0.90. The left leaflet width and right leaflet length are sufficient to estimate the leaf area. Network 4, trained with leaves from all groups, was the most general and suitable for the prediction of soybean leaf area.
{"title":"Area estimation of soybean leaves of different shapes with artificial neural networks","authors":"Ludimila Geiciane de Sá, C. Albuquerque, N. R. Valadares, O. G. Brito, Amara Nunes Mota, A. C. G. Fernandes, A. M. Azevedo","doi":"10.4025/actasciagron.v44i1.54787","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54787","url":null,"abstract":"Leaf area is one of the most commonly used physiological parameters in plant growth analysis because it facilitates the interpretation of factors associated with yield. The different leaf formats related to soybean genotypes can influence the quality of the model fit for the estimation of leaf area. Direct leaf area measurement is difficult and inaccurate, requires expensive equipment, and is labor intensive. This study developed methodologies to estimate soybean leaf area using neural networks and considering different leaf shapes. A field experiment was carried out from February to July 2017. Data were collected from thirty-six cultivars separated into three groups according to the leaf shape. Multilayer perceptrons were developed using 300 leaves per group, of which 70% were used for training and 30% for validation. The most important morphological measures were also tested with Garson’s method. The artificial neural networks were efficient in estimating the soybean leaf area, with coefficients of determination close to 0.90. The left leaflet width and right leaflet length are sufficient to estimate the leaf area. Network 4, trained with leaves from all groups, was the most general and suitable for the prediction of soybean leaf area.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"307 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74976506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-09DOI: 10.4025/actasciagron.v44i1.54364
Matheus Kainan de Paula Manjavachi, Tiago Alexandre Silva, Edvaldo A. A. Silva, C. C. Guimarães, M. Sartori
Water and salt stress conditions affect germination and seedling emergence. It is known that physiological priming can not only trigger different mechanisms to increase the speed and uniformity of germination, but also influence the antioxidant defence system of the seeds, especially in adverse conditions. In this context, the objective of this work was to evaluate the physiological seed quality and the activity of antioxidant enzymes in seeds of Petroselinum crispum induced to tolerate saline stress through osmo-priming. Seeds were placed in polyethylene glycol solutions with three osmotic potentials (-0.5, -1.0 or -1.5 MPa) for 2, 4 or 6 days. Subsequently, they were placed on substrates moistened with sodium chloride solution (NaCl), in concentrations that generated osmotic potentials of -0.2, -0.4, -0.6, -0.8 or -1.0 MPa, to germinate. The germination percentage, germination speed index, seedling length, fresh weight, dry weight and activity of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were evaluated. Germination and germination speed index decreased linearly with the increase in NaCl concentrations, indicating the species sensitivity. As for length, fresh weight and dry weight of seedlings, this effect was more expressive from the potential of -0.4 MPa. The vigour and activity of SOD, POD, and CAT enzymes were reduced in unprimed seeds, emphasising the effectiveness of the technique. The induction of tolerance to saline stress can be related to the activity of the antioxidant system observed in seeds.
{"title":"Physiological and biochemical responses of osmo-primed parsley seeds subjected to saline stress","authors":"Matheus Kainan de Paula Manjavachi, Tiago Alexandre Silva, Edvaldo A. A. Silva, C. C. Guimarães, M. Sartori","doi":"10.4025/actasciagron.v44i1.54364","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54364","url":null,"abstract":"Water and salt stress conditions affect germination and seedling emergence. It is known that physiological priming can not only trigger different mechanisms to increase the speed and uniformity of germination, but also influence the antioxidant defence system of the seeds, especially in adverse conditions. In this context, the objective of this work was to evaluate the physiological seed quality and the activity of antioxidant enzymes in seeds of Petroselinum crispum induced to tolerate saline stress through osmo-priming. Seeds were placed in polyethylene glycol solutions with three osmotic potentials (-0.5, -1.0 or -1.5 MPa) for 2, 4 or 6 days. Subsequently, they were placed on substrates moistened with sodium chloride solution (NaCl), in concentrations that generated osmotic potentials of -0.2, -0.4, -0.6, -0.8 or -1.0 MPa, to germinate. The germination percentage, germination speed index, seedling length, fresh weight, dry weight and activity of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were evaluated. Germination and germination speed index decreased linearly with the increase in NaCl concentrations, indicating the species sensitivity. As for length, fresh weight and dry weight of seedlings, this effect was more expressive from the potential of -0.4 MPa. The vigour and activity of SOD, POD, and CAT enzymes were reduced in unprimed seeds, emphasising the effectiveness of the technique. The induction of tolerance to saline stress can be related to the activity of the antioxidant system observed in seeds.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"94 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79596614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-09DOI: 10.4025/actasciagron.v44i1.54544
Cristiano Buchling, G.B.P. Braz, S. O. Procópio, C. Ferreira, A. Silva, J. Coradin
The succession of soybean/maize has been largely adopted. Storm damage and crop problems can lead to grain loss, generating maize ear fragments or even whole ears that remain in the soil and still display germination viability, resulting in the occurrence of volunteer plants. In this context, the present study aimed to evaluate the interference of voluntary maize plants on soybean and investigate the susceptibility of maize hybrids to pre-emergence herbicides. In the first step, an experiment was performed evaluating the influence of voluntary maize plant density and spatial distribution on soybean. The experiment was performed in a randomized completely block design (RCBD) with four replications, with treatments disposed in factorial arrangement (2 x 4) + 1. The first factor corresponded to the spatial distribution of maize plants: row or in between soybean rows; while the second factor adopted four infestation densities of maize plants m-2: 4, 8, 12, and 16. The additional treatment consisted of a control without maize plants. For the second step, an experiment was conducted in two locations aiming to determine the efficacy of pre-emergence herbicides in the control of voluntary maize. Both experiments were installed in RCBD in a split-plot scheme with four replications. Fomesafen, lactofen, sulfentrazone, chlorimuron-ethyl, diclosulam, flumetsulam, imazethapyr, clomazone, metribuzin, [sulfentrazone + diuron], [imazethapyr + flumioxazin], and a control without herbicide application were evaluated in the main plot. In each subplot, the maize hybrids DKB310 PRO3™ and DKB390 PRO3™ were evaluated. No influence on the position of voluntary maize on the soybean yield was observed. The presence of the maize population led to a progressive decrease in soybean yield, ranging up to 86%, at 16 plants m-2. DKB390 displayed a stand reduction of 82.88% after the use of diclosulam. Diclosulam led to better results regarding maize plant decreases for both hybrids.
{"title":"Pre-emergence control and interference of voluntary maize plants on a soybean crop in Brazilian Cerrado","authors":"Cristiano Buchling, G.B.P. Braz, S. O. Procópio, C. Ferreira, A. Silva, J. Coradin","doi":"10.4025/actasciagron.v44i1.54544","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54544","url":null,"abstract":"The succession of soybean/maize has been largely adopted. Storm damage and crop problems can lead to grain loss, generating maize ear fragments or even whole ears that remain in the soil and still display germination viability, resulting in the occurrence of volunteer plants. In this context, the present study aimed to evaluate the interference of voluntary maize plants on soybean and investigate the susceptibility of maize hybrids to pre-emergence herbicides. In the first step, an experiment was performed evaluating the influence of voluntary maize plant density and spatial distribution on soybean. The experiment was performed in a randomized completely block design (RCBD) with four replications, with treatments disposed in factorial arrangement (2 x 4) + 1. The first factor corresponded to the spatial distribution of maize plants: row or in between soybean rows; while the second factor adopted four infestation densities of maize plants m-2: 4, 8, 12, and 16. The additional treatment consisted of a control without maize plants. For the second step, an experiment was conducted in two locations aiming to determine the efficacy of pre-emergence herbicides in the control of voluntary maize. Both experiments were installed in RCBD in a split-plot scheme with four replications. Fomesafen, lactofen, sulfentrazone, chlorimuron-ethyl, diclosulam, flumetsulam, imazethapyr, clomazone, metribuzin, [sulfentrazone + diuron], [imazethapyr + flumioxazin], and a control without herbicide application were evaluated in the main plot. In each subplot, the maize hybrids DKB310 PRO3™ and DKB390 PRO3™ were evaluated. No influence on the position of voluntary maize on the soybean yield was observed. The presence of the maize population led to a progressive decrease in soybean yield, ranging up to 86%, at 16 plants m-2. DKB390 displayed a stand reduction of 82.88% after the use of diclosulam. Diclosulam led to better results regarding maize plant decreases for both hybrids.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89853390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-09DOI: 10.4025/actasciagron.v44i1.54392
J. C. A. Silva, E. P. Gonçalves, J. S. Viana, Cintya Mikaelly Pereira Gaia Souza, J. Borges, Wilaneide Ferreira Cavalcante
One way to reduce mineral fertilizers is to use alternative fertilizers instead, such as the byproducts from the food industry. In the present study we evaluated the effects of sugarcane bagasse ash on the physiology, growth, and development of sunflowers (Helianthus annuus L.). We conducted an experiment in a greenhouse using a completely randomized design with two sunflower cultivars (Multissol and Catissol), five sugarcane bagasse ash doses (0.0, 3.125, 4.687, 6.25, and 7.812 mg ha-1), and 5 replicates. At 85 days after planting we determined the plant height; leaf number; stem diameter; internal and external diameter of the flower chapter; leaf area index; shoot dry weight; net assimilation rate; dry mass production rate; relative and absolute growth rate; extravasation of electrolytes; relative water content; photosynthetic pigments (chlorophyll a, b, carotenoids, and the chlorophyll a/b ratio); and soluble carbohydrates, proteins, and proline. The height, number of leaves, and shoot dry mass increased due to the availability of nutrients contained in the ash. The incorporation of ash into the soil increased the photosynthetic activity (chlorophyll a and b) of both sunflower cultivars. The diameter of the stem, leaf area index, and relative growth rate of both sunflower cultivars increased with increasing ash dose. Therefore, the ash can be used as an alternative fertilizer, complementing or replacing mineral fertilizers.
{"title":"Growth and physiology of two sunflower cultivars fertilized with sugarcane bagasse ash","authors":"J. C. A. Silva, E. P. Gonçalves, J. S. Viana, Cintya Mikaelly Pereira Gaia Souza, J. Borges, Wilaneide Ferreira Cavalcante","doi":"10.4025/actasciagron.v44i1.54392","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54392","url":null,"abstract":"One way to reduce mineral fertilizers is to use alternative fertilizers instead, such as the byproducts from the food industry. In the present study we evaluated the effects of sugarcane bagasse ash on the physiology, growth, and development of sunflowers (Helianthus annuus L.). We conducted an experiment in a greenhouse using a completely randomized design with two sunflower cultivars (Multissol and Catissol), five sugarcane bagasse ash doses (0.0, 3.125, 4.687, 6.25, and 7.812 mg ha-1), and 5 replicates. At 85 days after planting we determined the plant height; leaf number; stem diameter; internal and external diameter of the flower chapter; leaf area index; shoot dry weight; net assimilation rate; dry mass production rate; relative and absolute growth rate; extravasation of electrolytes; relative water content; photosynthetic pigments (chlorophyll a, b, carotenoids, and the chlorophyll a/b ratio); and soluble carbohydrates, proteins, and proline. The height, number of leaves, and shoot dry mass increased due to the availability of nutrients contained in the ash. The incorporation of ash into the soil increased the photosynthetic activity (chlorophyll a and b) of both sunflower cultivars. The diameter of the stem, leaf area index, and relative growth rate of both sunflower cultivars increased with increasing ash dose. Therefore, the ash can be used as an alternative fertilizer, complementing or replacing mineral fertilizers.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"31 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84485350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-09DOI: 10.4025/actasciagron.v44i1.54249
G. S. Fialho, A. Fonseca, M. A. Ferrão, R. G. Ferrão, Tiago Olivoto, M. Nardino, E. F. Reis, N. S. Sakiyama
Coffee outturn can be defined as the ratio between the harvested coffee and its respective processed grains. This character is greatly influenced by genotypic and environmental effects, and in breeding programs your analysis is costly and time-consuming. In this sense, the use of an outturn index to estimate coffee yield on experimental plots is a desirable measure aiming at reducing resources and time in postharvest evaluations. Thus, the present study aimed to evaluate the accuracy of the use of an outturn index equal to 4.0, in the estimation of Conilon coffee grains production. This index indicates that four kilograms of harvested fruit would be needed to obtain one kilogram of processed grains. Based on the average of 157 genotypes conducted in three trials and four harvests, we evaluated the relationship between harvested fruits and processed grains (FcBe), the observed (OGY), and the estimated grain yield per plant (EGY) based on FcBe equal to 4.0 (an outturn index). Descriptive statistics, adequation test for EGY, and the coincidence of occurrence of genotypes observations relating to the top 20% of all observations of OGY and EGY. In the estimation of grain yield in Conilon, the use of FcBe equal to 4.0 showed high precision in the average of the analyzed trials. However, further studies should be conducted to elucidate the effects of climate variables on the yield of Conilon coffee, especially in atypical crop years. Thus, the use of an outturn index becomes interesting in cases where the number of genotypes to be evaluated is very large and a screening of the promising ones is desirable.
{"title":"Conilon coffee outturn index: a precise alternative for estimating grain yield","authors":"G. S. Fialho, A. Fonseca, M. A. Ferrão, R. G. Ferrão, Tiago Olivoto, M. Nardino, E. F. Reis, N. S. Sakiyama","doi":"10.4025/actasciagron.v44i1.54249","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.54249","url":null,"abstract":"Coffee outturn can be defined as the ratio between the harvested coffee and its respective processed grains. This character is greatly influenced by genotypic and environmental effects, and in breeding programs your analysis is costly and time-consuming. In this sense, the use of an outturn index to estimate coffee yield on experimental plots is a desirable measure aiming at reducing resources and time in postharvest evaluations. Thus, the present study aimed to evaluate the accuracy of the use of an outturn index equal to 4.0, in the estimation of Conilon coffee grains production. This index indicates that four kilograms of harvested fruit would be needed to obtain one kilogram of processed grains. Based on the average of 157 genotypes conducted in three trials and four harvests, we evaluated the relationship between harvested fruits and processed grains (FcBe), the observed (OGY), and the estimated grain yield per plant (EGY) based on FcBe equal to 4.0 (an outturn index). Descriptive statistics, adequation test for EGY, and the coincidence of occurrence of genotypes observations relating to the top 20% of all observations of OGY and EGY. In the estimation of grain yield in Conilon, the use of FcBe equal to 4.0 showed high precision in the average of the analyzed trials. However, further studies should be conducted to elucidate the effects of climate variables on the yield of Conilon coffee, especially in atypical crop years. Thus, the use of an outturn index becomes interesting in cases where the number of genotypes to be evaluated is very large and a screening of the promising ones is desirable.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"37 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78895039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-09DOI: 10.4025/actasciagron.v44i1.53751
R. Zampiróli, Matheus Vilhena Parenti, C. B. Alvarenga, F. J. Celoto, J. P. Cunha, P. C. Rinaldi
Chemical control is essential for efficient pest management in coffee crops. Application technologies should safely deliver insecticides to the target whilst protecting the environment, insecticide applicators, and consumers. To achieve these goals, application volumes, hydraulic nozzles, and application techniques should be evaluated. This study assessed the biological efficiency of different spray volumes and spray nozzles used to apply insecticides to control coffee berry borer (Hypothenemus hampei) populations. We applied insecticides using a hydropneumatic sprayer with and without an electrostatic spraying system. The experiment followed a randomized block factorial design (2 × 2 + 1) and included two types of spray nozzles [a hollow cone spray nozzle (JA1) and a hollow cone spray nozzle with air induction (TVI)], two spray volumes (200 and 400 L ha-1), one additional treatment (SPE2 nozzle with a 200 system 200 L ha-1), and six replicates. We assessed the control efficiency of the different application methods by evaluating the percentage of fruits damaged 20 and 40 days after the date of application. The spray volume did not affect the biological efficiency of pest control, and the lower spray volume (200 L ha-1) was effective in the control of coffee berry borers. Application of insecticides using coarse droplets was more efficient than the application using very fine and fine droplets. The TVI hydraulic spray nozzle effectively controlled coffee berry borers at 200 and 400 L ha-1. The electrostatic application system performed similarly to the conventional system in terms of the control of the coffee berry borers, and was less efficient than the conventional system under some operational conditions.
化学防治对咖啡作物害虫的有效治理至关重要。应用技术应在保护环境、杀虫剂施用者和消费者的同时,安全地将杀虫剂输送到目标。为了实现这些目标,应该对应用量、液压喷嘴和应用技术进行评估。研究了不同喷雾量和不同喷嘴对咖啡果螟种群的生物防治效果。我们使用带和不带静电喷雾系统的液压气动喷雾器施用杀虫剂。试验采用随机区因子设计(2 × 2 + 1),包括两种类型的喷嘴[空心锥喷嘴(JA1)和空心锥带空气诱导喷嘴(TVI)],两种喷雾量(200和400 L ha-1),一个附加处理(SPE2喷嘴与200系统200 L ha-1), 6个重复。通过对施药后20d和40d的果损率评价不同施药方式的防治效果。喷施量不影响生物防治效果,较低喷施量(200 L ha-1)对咖啡果螟虫的防治效果较好。粗滴施用比细滴施用效果好。TVI液压喷雾器在200和400 L ha-1下对咖啡浆果蛀虫有较好的控制效果。静电应用系统在控制咖啡浆果蛀虫方面的表现与常规系统相似,但在某些操作条件下不如常规系统有效。
{"title":"Use of different spray volumes and hydraulic nozzles in air-assisted electrostatic insecticide application technologies to control coffee berry borer (Hypothenemus hampei) populations","authors":"R. Zampiróli, Matheus Vilhena Parenti, C. B. Alvarenga, F. J. Celoto, J. P. Cunha, P. C. Rinaldi","doi":"10.4025/actasciagron.v44i1.53751","DOIUrl":"https://doi.org/10.4025/actasciagron.v44i1.53751","url":null,"abstract":"Chemical control is essential for efficient pest management in coffee crops. Application technologies should safely deliver insecticides to the target whilst protecting the environment, insecticide applicators, and consumers. To achieve these goals, application volumes, hydraulic nozzles, and application techniques should be evaluated. This study assessed the biological efficiency of different spray volumes and spray nozzles used to apply insecticides to control coffee berry borer (Hypothenemus hampei) populations. We applied insecticides using a hydropneumatic sprayer with and without an electrostatic spraying system. The experiment followed a randomized block factorial design (2 × 2 + 1) and included two types of spray nozzles [a hollow cone spray nozzle (JA1) and a hollow cone spray nozzle with air induction (TVI)], two spray volumes (200 and 400 L ha-1), one additional treatment (SPE2 nozzle with a 200 system 200 L ha-1), and six replicates. We assessed the control efficiency of the different application methods by evaluating the percentage of fruits damaged 20 and 40 days after the date of application. The spray volume did not affect the biological efficiency of pest control, and the lower spray volume (200 L ha-1) was effective in the control of coffee berry borers. Application of insecticides using coarse droplets was more efficient than the application using very fine and fine droplets. The TVI hydraulic spray nozzle effectively controlled coffee berry borers at 200 and 400 L ha-1. The electrostatic application system performed similarly to the conventional system in terms of the control of the coffee berry borers, and was less efficient than the conventional system under some operational conditions.","PeriodicalId":56373,"journal":{"name":"Acta Scientiarum. Agronomy.","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88629167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}