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The banana cv. Barranquillo (Musa acuminata, AAA, 'Gros Michel') is a highly desired fruit because of its productive potential and organoleptic quality but various aspects of the ripening process are unknown. The objective of this research was to evaluate the effect of applications of 1-MCP and ethylene on the ripening and degreening process. Two experiments were carried out at room temperature with fruits harvested at commercial maturity. The first four treatments evaluated maturation: control, ethylene, 1-MCP, and 1-MCP + ethylene. In the second experiment, different concentrations of ethylene based on ethephon (0, 100, 500 and 1000 µL L-1) were evaluated. The fruits treated with 1-MCP decreased the ripening process, and 1-MCP was a good alternative for conserving the fruits; the ethylene had opposite results. The color index of the skin, weight loss, firmness, total soluble solids, and maturity ratio had changes associated with the presence of ethylene. In the second experiment, the ethylene applications between 100 and 500 µL L-1 sufficiently stimulated degreening but accelerated the ripening process.
El banano cv. Barranquillo (Musa acuminata, AAA, 'Gros Michel') es un fruto muy apetecido por su potencial productivo y calidad organoléptica, pero se desconocen varios aspectos del proceso de maduración. El objetivo de esta investigación fue evaluar el efecto de la aplicación de 1-MCP y etileno en la maduración y en el proceso de desverdizado. Se realizaron dos experimentos a temperatura ambiente y con frutos cosechados en madurez comercial; en el primero, se evaluaron cuatro tratamientos, para entender la regulación de la maduración, estos fueron: testigo, etileno, 1-MCP y 1-MCP+etileno. En el segundo experimento, se evaluaron diferentes concentraciones de etileno, a base de etefon (0, 100, 500 y 1000 µL L-1). Los frutos tratados con 1- MCP presentaron una disminución en el proceso de maduración, por tanto, el 1-MCP, se convierte en una buena alternativa de conservación, mientras que con etileno, el proceso fue opuesto. Se evidenció que el índice de color de la epidermis, la pérdida de peso, la firmeza, los sólidos solubles totales y la relación de madurez se consideran cambios asociados a la presencia de etileno. En el segundo experimento se encontró que, aplicaciones de etileno entre 100 y 500µL L-1, se consideran suficientes para estimular el desverdizado, pero aceleran el proceso de maduración.
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Objective:To investigate the effect of ethephon exposure on sperm quality of adolescent male SD rats and the influence mechanism.Methods:A total of 40 45-day-old male SD rats were divided into control group and low, middle and high experimental groups according to the random number table method, 10 rats in each group.The said 4 groups were given 9 g/L normal saline, 100 mg/kg, 200 mg/kg, and 400 mg/kg ethephon aqueous solution for 28 days, respectively.One epididymal tail was taken to prepare sperm suspension, the sperm concentration and motility were detected.The testis and epididymis tissues were stained with HE, and their pathological changes were observed under light microscope.The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the malondialdehyde (MDA) content in the testis were detected.Enzyme linked immunosorbent assay kit was used to mea-sure the epididymal α-glucosidase activity, L-carnitine (LC) content, nuclear factor erythroid 2-related factor 2 (Nrf2) and organic cation transporter 2 (OCTN2) expression levels.Then the oxidative damage caused by ethephon to epididymis was evaluated.SPSS 26.0 software was used for data analysis.Data were compared by One- way ANOVA among groups and LSD method between 2 groups. Results:The sperm concentration of the control group, low, medium and high dose groups were (40.21±1.94)×10 9/L, (35.23±2.53)×10 9/L, (23.61±2.62)×10 9 /L, and (18.86±2.16)×10 9 /L, respectively.The sperm activity rate were (70.98±3.01)%, (57.96±3.75)%, (45.71±2.41)%, and (31.23±2.26)%, respectively.The concentration and vitality of epididymal sperms in the experimental group were significantly lower than those in the control group (all P<0.01). In the control group, low, medium and high dose groups, the SOD activity were (46.48±2.21) U/mg prot, (38.49±2.56)U/mg prot, (33.80±1.73) U/mg prot, and (27.65±2.05) U/mg prot, respectively.The GSH-Px activity in said 4 groups were (21.41±1.95) U/mg prot, (17.32±1.28) U/mg prot, (15.09±0.94) U/mg prot, and (14.08±1.23) U/mg prot, respectively.The MDA content in said 4 groups were (1.41±0.09) nmol/mg prot, (1.59±0.09) nmol/mg prot, (1.81±0.09) nmol/mg prot, and (2.16±0.14) nmol/mg prot, respectively.Compared to the control group, the experimental groups had significantly lower SOD and GSH-Px activities and significantly higher MDA content (all P<0.05). α-glucosidase levels in the control group, low, middle and high experimental groups were (15.46±0.71) U/mL prot, (12.95±0.72) U/mL prot, (11.34±0.65) U/mL prot, and (8.76±0.60) U/mL prot, respectively.LC levels in the control group, low, middle and high dose groups were(6.21±0.31) μg/L, (5.89±0.13) μg/L, (5.02±0.12) μg/L, (4.38±0.07) μg/L, respectively, compared with those of the control group, the concentration of α-glucosidase and LC in experimental groups decreased significantly (all P<0.01). The expression levels of Nrf2 in epididymis of the control group, low, middle and high dose groups were (1.34±0.05) ng/L, (1.25±0.04) ng/L, (1.08±0.06) ng/L, (0.92±0.04) ng/L, respectively; the expression levels of OCTN2 in epididymis of the control group, low, middle and high dose groups were (4.55±0.12) ng/L, (4.23±0.11) ng/L, (3.20±0.24) ng/L, (2.59±0.05) ng/L, respectively, compared with those of the control group, the expression levels of Nrf2 and OCTN2 in experimental groups decreased significantly (all P<0.01). Conclusions:Ethephon exposure leads to excessive generation of reactive oxygen and oxidative stress in reproductive organs.Ethephon exposure may activate the Keap1-Nrf2/ARE signal pathway, resulting in a decrease in the number, vitality and quality of sperms, and impaired fertility.
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Peach tree thinning, whichaims at reducing plant load so as to ensure productivity and fruit quality, has been manually carried out within a short period of time in the stage of fruit development. Due to the need and shortage of qualified man power, chemical thinning is one of the alternatives that can solve these difficulties found in manual thinning. This study aimed at evaluating the effect of different products which have been applied either alone or in combination to fruit thinning of peach tree cultivars 'Sensação' and 'Maciel' in Pelotas, Rio Grande do Sul (RS) state, Brazil. The experiment was conducted in the 2015/2016 crop in a commercial peach orchard located in Morro Redondo, RS, Brazil. The following seven treatments were carried out 40 days after full bloom (DAFB): plants with no thinning, manual thinning, metamitron, benzyladenine, benzyladenine + metamitron, ethephon, ethephon + metamitron. Fruit abscission, effective fructification, number of fruits and production per plant, mean mass and fruit classification into caliber classes, epidermis color, pulp firmness and soluble solids were evaluated. Production and number of fruits per plant decreased excessively, whereas fruits placed in categories of higher caliber increased when ethephon was either used alone or in combination with metamitron. When both metamitron and benzyladenine were applied, either alone or in combination, they led to fruit abscission and resulted in mean fruit size and weight, at harvest time, similar to those found in manual thinning. Application of chemical products either alone or in combination may be an alternative of peach tree thinning in orchard management.
O raleio em pessegueiro visa reduzir a carga da planta para assegurar a produtividade e a qualidade dos frutos, sendo realizado manualmente em um curto período durante a etapa de desenvolvimento dos frutos. Devido à exigência e falta de mão de obra qualificada, o raleio químico é uma das alternativas para suprir essa demanda encontrada no raleio manual. O objetivo deste trabalho foi avaliar o efeito de diferentes produtos aplicados de forma isolada ou combinada no raleio de frutos de pessegueiros das cultivares Sensação e Maciel na região de Pelotas. O experimento foi conduzido na safra 2015/2016, em pomar comercial de pessegueiro localizado no município de Morro Redondo, RS. Foram realizados sete tratamentos aos 40 dias após a plena floração, consistindo em plantas sem raleio, raleio manual, metamitron, benziladenina, benziladenina + metamitron, ethephon, ethephon + metamitron. Avaliou-se a abscisão dos frutos, frutificação efetiva, número de frutos e produção por planta, massa média e classificação dos frutos em classes de calibre, coloração da epiderme, firmeza de polpa e sólidos solúveis. A produção e o número de frutos por planta reduziram excessivamente, enquanto a alocação dos frutos em categorias de maior calibre aumentou, quando utilizado o ethephon isolado ou em combinação com o metamitron. O metamitron e a benziladenina aplicados isolados ou em combinação promoveram a abscisão dos frutos e resultaram em tamanho e peso médio dos frutos na colheita semelhantes aos provenientes do raleio manual. Aplicação de produtos químicos isolados ou em combinação pode ser uma alternativa de manejo dos pomares para o raleio de pessegueiros.
Subject(s)
Prunus persica , Crop Production/methods , Crop ProductionABSTRACT
Ethephon (Ethrel®) is an ethylene-based plant growth regulator that used in agriculture and it has direct and indirect effects on human health, direct effect via its inhalation during usage in agriculture and indirect effect through the diet (Fruits and vegetables) that is sprayed with it. The current study aimed to examine the possible modifying effects of costus (Saussurea lappa) root aqueous extract against Ethephon induced liver toxicity, injury, DNA fragmentation and PCNA alterations in male rats. Fifty adult male rats were divided into 5 groups (1st, control; 2nd, Costus; 3rd, Ethephon; 4th, Post treated Ethephon with costus; 5th, self-healing Ethephon). Current results revealed that; a significant increase in aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), liver injury, DNA damage and PCNA expressions in Ethephon group when compared with control group. In contrast; a significant decrease in albumin and total proteins in Ethephon group when compared with control group. Treatment of rats with costus after Ethephon improved these alterations as compared with Ethephon self-healing. So, it could be concluded that costus root extract worth to be considered as a natural substance for ameliorating the hepatic toxicity induced by plant growth regulator Ethephon.
Subject(s)
Animals , Male , Rats , Plant Growth Regulators/agonists , Plant Extracts/analysis , Costus/adverse effects , Chemical and Drug Induced Liver Injury , DNA Damage , Inhalation , Proliferating Cell Nuclear Antigen , Agriculture/classification , Liver/abnormalitiesABSTRACT
Objective@#To investigate the effect of Ethephon on the testis pathological structure and apoptosis of spermatogenic cell in offspring male rats.@*Methods@#Twenty-four healthy female SD rats of 45 days old were randomly divided into control group, low-dose Ethephon group, medium-dose Ethephon group and high-dose Ethephon group according to body weight.The male rats of the same age were selected to mate with female rats.The rats were fed with Ethephon solution of different concentrations or 9 g/L saline every day, and they were continued to be fed with Ethephon during pregnancy and lactation.At the age of 7 days and 14 days, 10 offspring male rats were randomly selec-ted from each group and were put to death.The testicular tissue was stained with HE, and the morphological changes in the testis were observed with light microscope; the apoptotic cells were labeled with terminal deoxynucleotidyl transfe-rase dUTP nick-end labeling (TUNEL method) and the apoptosis index(AI) of testis spermatogenic cells was detected with fluorescence microscope.@*Results@#At the age of 7 days, the testis internal structure of the control group developed well, and the spermatic tubules were neatly and compactly arranged.In the low-dose Ethephon group, the seminiferous tubules of the testis were slightly smaller and the spermatogenic cells were loosely arranged compared with the control group.In the medium-dose Ethephon group, the testis seminiferous tubules were slightly disordered and the cell gap increased.In the high-dose Ethephon group, the testis development was poor, the diameter of seminiferous tubules decreased significantly, and the spermatogenic cells arrangement was in disorder.There was no statistically significant difference in spermatogenic cell AI between the low-dose group [(0.54±0.10)%] and the control group[(0.53±0.09)%] (P>0.05), while the spermatogenic cell AI in the medium-dose Ethephon group [(0.63±0.11)%] and the high-dose Ethephon group [(0.81±0.06)%] were higher than that in the control group, thus there exists a statistically significant difference (all P<0.01). The spermatogenic cell AI in the low-dose Ethephon group [(0.54±0.10)%] was lower than that in the medium-dose Ethephon group [(0.63±0.11)%], and the difference was statistically significant (P<0.05). The spermatogenic cell AI in the medium-dose Ethephon group was higher than that in the high-dose Ethephon group, and the difference was statistically significant (P<0.01). At the age of 14 days, the spermatogenic cells AI in control group, low-dose Ethephon group, medium-dose Ethephon group and high-dose Ethephon group were (0.54±0.08)%, (0.65±0.11)%, (0.77±0.11)%, and (0.88±0.10)% respectively, and the spermatogenic cells AI in all groups increased gradually, in which the differences were statistically significant (all P<0.01).@*Conclusions@#Excessive dose of Ethephon can induce pathological changes in testicular tissue and increase the apoptosis of spermatogenic cells, resulting in low fertility of offspring rats.
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Objective To investigate the effect of Ethephon on the testis pathological structure and apoptosis of spermatogenic cell in offspring male rats.Methods Twenty-four healthy female SD rats of 45 days old were randomly divided into control group,low-dose Ethephon group,medium-dose Ethephon group and high-dose Ethephon group according to body weight.The male rats of the same age were selected to mate with female rats.The rats were fed with Ethephon solution of different concentrations or 9 g/L saline every day,and they were continued to be fed with Ethephon during pregnancy and lactation.At the age of 7 days and 14 days,10 offspring male rats were randomly selected from each group and were put to death.The testicular tissue was stained with HE,and the morphological changes in the testis were observed with light microscope;the apoptotic cells were labeled with terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL method) and the apoptosis index(AI) of testis spermatogenic cells was detected with fluorescence microscope.Results At the age of 7 days,the testis internal structure of the control group developed well,and the spermatic tubules were neatly and compactly arranged.In the low-dose Ethephon group,the seminiferous tubules of the testis were slightly smaller and the spermatogenic cells were loosely arranged compared with the control group.In the medium-dose Ethephon group,the testis seminiferous tubules were slightly disordered and the cell gap increased.In the high-dose Ethephon group,the testis development was poor,the diameter of seminiferous tubules decreased significantly,and the spermatogenic cells arrangement was in disorder.There was no statistically significant difference in spermatogenic cell AI between the low-dose group [(0.54 ± 0.10)％] and the control group[(0.53 ±0.09) ％] (P ＞ 0.05),while the spermatogenic cell AI in the medium-dose Ethephon group [(0.63 ± 0.11) ％]and the high-dose Ethephon group [(0.81 ± 0.06) ％] were higher than that in the control group,thus there exists a statistically significant difference (all P ＜0.01).The spermatogenic cell AI in the low-dose Ethephon group [(0.54 ±0.10) ％] was lower than that in the medium-dose Ethephon group [(0.63 ± 0.11)％],and the difference was statistically significant (P ＜ 0.05).The spermatogenic cell AI in the medium-dose Ethephon group was higher than that in the high-dose Ethephon group,and the difference was statistically significant (P ＜0.01).At the age of 14 days,the spermatogenic cells AI in control group,low-dose Ethephon group,medium-dose Ethephon group and high-dose Ethephon group were (0.54 ± 0.08) ％,(0.65 ± 0.11) ％,(0.77 ± 0.11) ％,and (0.88 ± 0.10) ％respectively,and the spermatogenic cells AI in all groups increased gradually,in which the differences were statistically significant (all P ＜ 0.01).Conclusions Excessive dose of Ethephon can induce pathological changes in testicular tissue and increase the apoptosis of spermatogenic cells,resulting in low fertility of offspring rats.
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ABSTRACT: The 'Montenegrina' mandarin ( Citrus deliciosa Tenore) is widely cultivated in southern Brazil. This cultivar has a great tendency for alternate bearing, requiring thining of the fruit. However, the chemical thinners studied until now in this cultivar have not been successful. The objective of this research was to evaluate the effect of 3,5,6-trichloro-2-pyridinyloxyacetic acid (3,5,6-TPA) on the production and fruit quality of the 'Montenegrina' mandarin, in comparison with hand thinning and the options of chemical thinning previously studied. Hand thinning and no thinning were used as controls. Ethephon was applied in three doses: 200mg L-1, 300mg L-1 or 200mg L-1 + 3% urea; or 3,5,6-TPA, in four doses: 10, 20, 30 or 40mg L-1. Fruits of the hand thinned trees and those treated with 40mg L-1 showed greater average size, greater distribution of commercial caliber and more orange colors. No treatment reduced alternate bearing. Applications of 40mg L-1 of 3,5,6-TPA as a chemical thinner, during the physiological drop of young fruit, had a similar effect that of hand thinning over yield and quality of fruits of 'Montenegrina' mandarin.
RESUMO: A tangerineira 'Montenegrina' ( Citrus deliciosa Tenore) é amplamente cultivada no sul do Brasil. Possui grande tendência à alternância de produção, necessitando de raleio de frutos. Contudo, os raleantes químicos estudados até hoje nesta cultivar não se demonstraram eficientes. Este trabalho teve como objetivo avaliar o efeito do ácido 3,5,6-tricloro-2-piridiniloxiacético (3,5,6-TPA) sobre a produção e qualidade de frutos da tangerineira 'Montenegrina', em relação às opções de raleio químico previamente estudadas. Foram utilizados, como padrão, raleio manual e plantas sem raleio (controle). Realizaram-se aplicações de ethephon em três doses: 200mg L-1, 300mg L-1 e 200mg L-1 + 3% de ureia; e aplicações de 3,5,6-TPA, em quatro doses: 10, 20, 30 e 40mg L-1. Os frutos de árvores raleadas manualmente e de tratadas com 3,5,6-TPA a 40mg L-1 apresentaram maior tamanho médio, melhor distribuição de calibres comerciais e cores mais alaranjadas. Nenhum tratamento reduziu a alternância de produção. Aplicações de 40mg L-1 de 3,5,6-TPA como raleante químico, durante a queda fisiológica de frutos jovens, propiciaram efeito similar ao raleio manual sobre a produção e qualidade dos frutos de tangerineira 'Montenegrina'.
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Objective To investigate the effects of Ethephon on spermatogenic cells and sex hormones levels of adolescent male rats.Methods The male SD rats of 25-day old were randomly (from the random number table) divided into high dose group (2 000 mg/kg),middle dose group (1 000 mg/kg),low dose group (500 mg/kg) and control group (the same amount of physiological saline).They were given Ethephon through stomach for 14 d.The pathological changes in testis tissues were observed by HE staining.The apoptosis of germ cells were detected by terminal transferase labeling (TUNEL).The automatic chemical luminescence immunoassay analyzer was used to test the serum sex hormone levels.Results After ethephon and saline lavage for 14 days in the dose of 2 000 mg/kg,1 000mg/kg,500 mg/kg concentrations respectively,body weight growth was significantly decreased (F =3.58,P =0.03).Testis mass growth [(0.91 ± 0.17) g,(1.13 ± 0.15) g,(1.21 ± 0.11) g,(1.29 ± 0.28) g] was significantly decreased (F =4.31,P =0.02).Experimental group spermatogenic cell apoptosis,the apoptosis index increased (F =156.00,P =0.00),high dose group[(2.40 ±0.18)％] and middle dose group[(1.72 ±0.14)％] was significandy increased (P ＜ 0.01).The levels of testosterone and estrogen in serum showed a decreasing trend along with the increase of the doses,and there was a statistical significance (F =11.85,38.93,all P =0.00).Compared with the control group [(0.86 ± 0.10) μg/L],the testosterone levels in high dose group [(0.31 ± 0.08) μg/L],middle dose group [(0.36± 0.05) μg/L] decreased significantly (P ＜ 0.01).Compared with the control group,low dose group,middle dose group [(36.43 ± 3.57) ng/L,(38.62 ± 2.24) ng/L,(31.87 ± 5.78) ng/L],the estrogen level in high dose group[(27.39 ± 2.11) ng/L] was significantly reduced (P ＜ 0.01).Conclusion Ethephon has reproductive toxicity,and can cause the serum level of testosterone and estradiol decreased,resulting in spermatogenic cell apoptosis index increased and the spermatogenic capability decreased.
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Conduziu-se este trabalho, com o objetivo de avaliar a atividade das enzimas invertases ácida e neutra e sua influência no processo de regulação do acúmulo de sacarose nos colmos da cana-de-açúcar, cultivar RB855453, sob efeito do nitrato de potássio comparado aos maturadores, da classe dos retardantes do crescimento, etefon e etil-trinexapac, buscando contribuir para o entendimento da ação desse composto químico. Os tratamentos constituíram-se da aplicação de quatro maturadores da classe dos retardantes do crescimento, cujos ingredientes ativos são etefon, etil-trinexapac, nitrato de potássio e nitrato de potássio + boro, e a maturação natural como testemunha, em delineamento experimental em blocos casualizados com cinco repetições. Os níveis enzimáticos das invertases ácida e neutra foram afetados de forma e intensidade distintas em função do princípio ativo utilizado como maturador e das condições climáticas; contudo, de forma geral, os níveis da invertase ácida manifestaram-se superiores aos da invertase neutra sem comprometer o acúmulo de sacarose nos colmos da cana-de-açúcar cultivar RB855453. O nitrato de potássio apresentou efeito maturador na cultura da cana-de-açúcar possibilitando o acúmulo de sacarose nos colmos, contudo as condições climáticas afetaram sua eficiência agronômica, tendo em vista que atua como indutor do processo de maturação.
The objective of this work was to evaluate the acid and neutral invertases enzymes activity and its influence in process of regulation sucrose accumulation in stems of RB855453 variety sugarcane under effect the potassium nitrate in compared with ripeners, of class of retainers growth, ethephon and ethyl-trinexapac, for to contribute the understanding of act this chemical compost. The treatments consisted of four ripeners of class of growth retainers, which active ingredient are ethefon, ethyl-trinexapac, potassium nitrate and potassium nitrate + boron and natural ripener as control, in a randomized block design with five replicates. The acid and neutral invertases enzymes levels were affected of form and intensity differents due active ingredient used as ripening and weather conditions; however, in general, the acid invertase levels were greatest the neutral invertase whitout to compromise the sucrose accumulation in stems of RB855453 cultivar sugarcane. The Potassium nitrate had effect ripener in sugarcane allowing sucrose accumulation in stems, however the weather conditions affected its agronomical efficiency, therefore act as inducers of the ripening process.
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As características ambientais e a exposição das plantas e frutas à insolação podem influenciar no crescimento das plantas e qualidade da produção. O trabalho foi realizado em um pomar comercial, com o objetivo de avaliar as características físico-químicas em relação à disposição na copa de frutas de tangerineira 'Ponkan', submetidas ao raleio químico. Foram avaliados quatro tratamentos, dispostos em esquema fatorial 2 x 2, no delineamento de blocos casualizados, com oito repetições. Os fatores foram as concentrações de Ethephon, 0 e 600 mg L-1 e dois quadrantes de localização das frutas na copa, leste e oeste. As frutas de tangerineira 'Ponkan', localizadas no quadrante oeste da copa, apresentaram tamanho e teor de sólidos solúveis maiores e menor acidez, quando comparadas com aquelas do quadrante leste. A aplicação de Ethephon para promover o raleio químico melhorou a qualidade das frutas de tangerineira 'Ponkan' em todas as posições analisadas na copa.
Plant growth and production quality can be influenced by environmental characteristics and sunlight exposure of plants and fruits. The objective of this study was to evaluate physico-chemical characteristics in relation to canopy distribution of 'Ponkan' mandarin fruits submitted to chemical thinning in a commercial orchard. Four treatments were tested, set in 2 x 2 factorial scheme with eight randomized block replications. The factors were Ethephon concentrations (0 and 600 mg L-1 and two quadrants of canopy fruit distribution (east and west). The 'Ponkan' mandarin fruits located in the west quadrant presented greater size and solid soluble content and lesser acidity, as compared to those in the east quadrant. Chemical thinning with Ethephon application improved the quality of the 'Ponkan' mandarin fruits in all the canopy positions analyzed.
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O objetivo neste trabalho foi a avaliação da atividade das invertases ácida e neutra e a função que essas exercem no controle do acúmulo de sacarose em cana-de-açúcar, variedade SP80-3280, decorrente da aplicação de reguladores vegetais no meio de safra, em Igaraçu do Tietê (SP). O experimento foi conduzido em cana soca, em safras consecutivas (2004 e 2005). O delineamento experimental utilizado foi em blocos casualizados, com cinco repetições. Os tratamentos foram constituídos da aplicação de quatro reguladores vegetais da classe dos retardadores do crescimento (Etefon, Etil-trinexapac, KNO3 e KNO3 + Boro) e uma testemunha (maturação natural), comercialmente encontrados como Ethrel, Moddus, Krista Kana e Krista Kana Plus, respectivamente, adotando-se a dosagem do produto comercial: 2L ha-1, 0,8L ha-1, 3kg ha-1 e 3kg ha-1, respectivamente, sem a adição de adjuvantes. Os reguladores vegetais promovem alterações de intensidades distintas e significativas nos níveis enzimáticos das invertases ácida e neutra. A eficiência agronômica dos maturadores foi afetada de forma significativa pelo clima e pela época de aplicação. Os tratamentos com maturadores, principalmente em 2004, cujas condições climáticas foram desfavoráveis à maturação natural, favoreceram o processo de maturação da cana-de-açúcar, implicando em melhorias da qualidade tecnológica dos colmos.
The objective of this research was to evaluate the activity of acid and neutral invertases in controling the storage of sucrose in sugarcane variety SP80-3280 due to plant regulators application in the middle of the cropping season in Igaraçu do Tietê (SP), Brazil. The experiment was carried out in ratoon cane (crop 2004 and 2005) in a randomized block design with five replications. The treatments consisted of four plant regulators application of the class of growth retainers (Ethephon, Ethyl.trinexapac, Potassium nitrate and Potassium nitrate + Boron) and a control (natural ripening), whose commercial products (c.p.) were Ethrel, Moddus, Krista Kana and Krista Kana Plus, with dosage of 2L c.p. ha-1, 0.8L c.p. ha-1, 3kg c.p. ha-1 and 3c.p. kg ha-1, respectively, without adjuvants application. The growth regulators provide alterations of different and significant intensity in soluble acid invertase and neutral invertase levels enzymes. The agricultural efficiency of maturators was affected significatively by the weather and time of application. The treatments with maturators, were affected most in 2004, when wheater conditions were unfavourable to natural ripening, were favour the ripening sugarcane process implicating in improvement technological quality of stems.
ABSTRACT
A maturação da cana-de-açúcar é um dos aspectos fundamentais para a produção da indústria sucroalcooleira. O objetivo neste trabalho foi avaliarem-se a qualidade tecnológica, a produtividade e a margem de contribuição agrícola da cana-de-açúcar, variedade RB855453, em função da aplicação de reguladores vegetais no início da safra, em Igaraçu do Tietê (SP). O delineamento experimental utilizado foi o de blocos casualizados, com cinco repetições, sendo os tratamentos constituídos da aplicação de quatro maturadores da classe dos retardantes de crescimento (Etefon, Etil-trinexapac, KNO3 e KNO3 + Boro, na dosagem do produto comercial de, 2L ha-1, 0,8L ha-1, 3kg ha-1, e 3kg ha-1, respectivamente) e uma testemunha (maturação natural). Os maturadores, de forma geral, propiciaram melhoria na qualidade tecnológica da matéria-prima, com reflexo positivo na produtividade de açúcar e na margem de contribuição agrícola. Os maturadores KNO3 + Boro, Etefon e Etil-trinexapac, sob condição climática desfavorável ao processo de maturação natural (safra 2004), permitiram antecipar a colheita em cinco, oito e vinte cinco dias, respectivamente, em relação ao controle. Na safra subseqüente, sob condição climática favorável ao processo de maturação natural, os maturadores pouco anteciparam o corte da matéria-prima em comparação à testemunha.
The ripening sugarcane is the most important aspect in production sistem for sugar and alcohol industry. The objective of this research was to evaluate technological quality, productivity and agricultural contribution margin of sugarcane variety RB855453 in function of plant regulators application at the beginning of the cropping season, in Igaraçu do Tietê (SP), Brazil was studied. The experiment was carried out in a randomized block design with five replications. The treatments consisted of four plant regulators application of the class of growth retainers (Ethephon, Ethyl.trinexapac, Potassium nitrate and Potassium nitrate + Boron, in dosage commercial products of 2L ha-1, 0.8L ha-1, 3kg ha-1, e 3kg ha-1, respective) and a control (natural ripening). The maturators, general manner, provided the improvement technological quality of stems with positive reflex in productivity of sugar and agricultural contribution margin. The maturators Potassium nitrate + Boron, Ethephon and Ethyl-trinexapac, under weather conditions unfavourable to natural ripening process of sugarcane, allowed to anticipate the crop in five, eight, and twenty-five days, respectively, in relation a control treatment. In the subsequent crop season, under optimus weather conditions the ripening process of sugarcane, had no difference when compared to the control treatment.
ABSTRACT
A maturação da cana-de-açúcar (Saccharum officinarum L.) refere-se a um dos aspectos fundamentais para o sistema de produção da indústria sucroalcooleira. Objetivou-se, neste trabalho, avaliar a qualidade tecnológica da cana-de-açúcar em função da aplicação de reguladores vegetais em meio de safra. O delineamento experimental utilizado foi o de blocos casualizados com cinco repetições, sendo os tratamentos constituídos da aplicação de quatro maturadores da classe dos retardantes de crescimento (Ethefon, Etil-trinexapac, KNO3 e KNO3 + Boro) e uma testemunha (maturação natural). A eficiência agronômica dos maturadores foi influenciada pela época de aplicação, pela condição climática e pela característica genética da variedade. A aplicação dos maturadores em 10/05/2004 permitiu explorar de forma significativa o potencial genético da variedade quanto ao acúmulo de sacarose nos colmos, implicando em melhoria na qualidade tecnológica da matéria-prima. A adoção dessa prática em 04/08/2005, de modo geral, pouco afetou os parâmetros tecnológicos, exceto a aplicação de Etil-trinexapac, o qual induziu melhoria significativa na qualidade da matéria-prima. A produtividade de açúcar refletiu-se de forma direta na margem de contribuição agrícola, sendo constatado maior retorno econômico para as plantas tratadas com KNO3 na safra 2004.
The ripening of sugarcane (Saccharum officinarum L.) is the most important aspect in the production system for sugar and alcohol industry. The objective of this work was to evaluate the technological quality of sugarcane as a function of plant regulators application in the middle of the cropping season. The experiment was carried out in a randomized block design with five replications. The treatments consisted of four plant regulators application of the class of growth retainers (Ethephon, Ethyl.trinexapac, Potassium nitrate and Potassium nitrate + Boron) and a control (natural ripening). The agricultural efficiency of maturators was affected by time application, weather condition and genetic characteristic of variety. The maturation application on 10/05/2004 allowed to explore of a significant form the genetic potential of variety as to sucrose storage in stems implicating in improvement technological quality of raw material. The maturation application on 04/08/2005 little affected technological parameters, except for Ethyl-trinexapac application, that induced significant improvement in technological quality of raw material. The sugar productivity reflected direct agricultural contribution and provided greater economical return with Potassium nitrate treatment in 2004.
ABSTRACT
Object To provide the theoretical basis for the artificial planting of Hypericum perforatum L., the effects of light, gibberellin and ethephon on the germination of H. perforatum seeds were studied. Methods The method of direct germination was used. Results The seeds germinated to 79% in the light, while didn't germinate in the dark. Gibberellin and ethephon not only promoted the germination in the light, but also induced the germination in the dark. But ethephon inhibited the growth of seedling radicals severely. Conclusion The seed of H. perforatum is light-dependent seed, its light-dependence is related to gibberellin and ethephon.