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Abstract The objective of this work was to evaluate the effect of the use of the Murashige & Skook (MS) and Linsmaer & Skoog (LS) media and of filter caps on culture flasks on the morphological and physiological characteristics of basil cultivars in vitro, as well as to determine the composition of the essential oil of plants acclimatized in pots. For the evaluation of the cultivation media, cultivars Anise, Cinnamon, Grecco a Palla, and Italian Large Leaf were used. The Anise, Cinnamon, Italian Large Leaf, and Maria Bonita cultivars were used for the evaluation of the use of filter caps. The composition of the essential oils of cultivars Anise, Cinnamon, and Italian Large Leaf was also evaluated. The basil seedlings showed a higher aerial-part dry mass and a lower hyperhydricity rate when grown in the MS medium. The flasks without filter caps produced seedlings with lower contamination rates. When acclimatized in pots, cultivars Limoncino and Anise presented the tallest plants with the largest crown diameters. In the composition of essential oils, methyl cinnamate and linalool stood out in cultivar Cinnamon, methyl chavicol in Anise, and linalool in Italian Large Leaf. In the in vitro cultivation, the evaluated cultivars present a higher aerial-part production in the MS medium and a lower contamination without the use of filters, whereas, in the pots, the composition of essential oils varies according to the cultivar.

Abstract: The objective of this work was to evaluate how salt concentrations in media used for in vitro cultures affect the early development of “barueiro” (Dipteryx alata) seedlings obtained from the shoot apex. Two different in vitro culture media - Murashige & Skoog (MS) and wood plant medium (WPM) - in different salt concentrations (25, 50, 75, and 100%) were used. At 120 days, the D. alata seedlings in the MS medium, in its original concentration (100%), developed better than in other concentrations or in the WPM. Therefore, the MS medium was considered the most suitable for ensuring in vitro establishment because it provided greater root length (27.65 cm) and number of leaves per plant (26 leaves) than the other medium.

ABSTRACT: Lavender is an aromatic ornamental plant that is used widely in the perfume, pharmaceutical, cosmetical and food industries. That is why it is important to study ways to promote a production of lavender raw material. For this, four experiments were carried out in order to study the germination and initial in vitro development of lavender. In the first part the efficiency of the use of hydrogen peroxide in the pre-treatment of seeds inoculated in culture media with different concentrations of gibberellic acid was evaluated. Besides that, the influence of the use of Growlux lamps and white fluorescent lamps on plantlets cultivated in MS and LS media at salts concentrations of 50 and 100% was evaluated. Finally, the effect of the gibberellic acid, putrescine, spermine and spermidine in different concentrations was evaluated. Better results were estimated when hydrogen peroxide pretreatment was applied to the seeds with subsequent inoculation in a medium containing 2,5 mg L-1 of gibberellic acid. The use of Growlux lamps did not influence the characteristics observed when compared to the use of white fluorescent lamps, however it was concluded that the species develops more in a LS medium. Concerning the use of polyamines was found that germination, aerial part and number of leaves of the seedlings were generally favored at the concentration of 0,5 mg L-1 except when spermine was applied, which resulted in a lower number of leaves under this condition.

The barueiro (Dipteryx alata Vog.) is a native fruit species of the Cerrado ecoregion that has multiple uses. It is a wild species, and its cultivation is difficult. Furthermore, it is threatened with extinction. Plant tissue culture is a major tool for the conservation of germplasm, as well as a means of propagating high-quality seedlings on a large scale. However, this technique has not been used with barueiro, although it might provide valuable contributions to the process of barueiro domestication. The most popular method of cultivation is the use of the Murashige and Skoog medium (MS), which is considered one of the most nutritionally complete media. Woody plant medium (WPM) is indicated for the propagation of woody species, but there are no reports of its use for barueiro cultivation. Woody plants tend to have problems with rust in vitro during the establishment phase. Activated charcoal acts as an adjuvant for the adsorption of phenolic compounds, mitigating its effects in the medium. Thus, the objective of this study was to test four activated charcoal doses (0, 2, 4 and 6 g L-1) and three culture media: MS, WPM, and AA (over water agar) in the in vitro establishment of barueiro. The experimental design was a completely randomised (DIC), 4 × 3 factorial design with three replications. At 60 days after inoculation, the explants were evaluated for dry matter, fresh weight, stem diameter, shoot length, number of leaves, longest root length, germination rate, and chlorophyll contents. The MS medium supplemented with 3,0 g L-1 activated charcoal appeared to be the best for in vitro establishment of barueiro.

Statistical analyses are an essential part of scientific research. Various procedures since the preparation of the experiment have an impact on the statistical procedures adopted. Therefore, a correct planning implies a precise analysis. Through sampling which used a reliability interval at 95% and error margin at 7%, this study aimed to characterize the statistics used by researchers in the field of plant tissue culture, and based on the results, discuss the main impacts of their misuse. Information regarding sample size; number of repetitions; delineation; scheme adopted (factorial or otherwise) and number of treatments; use (or lack of) data transformation; type of the variable (quantitative or qualitative), test and regression types was quantified. Even with consistent use of statistics in plant tissue culture experiments some hindrances remain, such as the size of the portions and the reduced number of repetitions. Added to this, the transformation of data in which criteria for adoption is not reported or informed, or use of ill-informed criteria. Even considering homogeneous conditions, neglecting to use blocking in experiments may misguide researchers. Blocking is recommended to increase the size of the sample, with time as blocking factor, or the human factor involved in the installation of the experiment. The use of factorial designs has been characteristic of the area, which aims to define doses and plant regulators, so the experiments present large number of treatments. For comparison, Tukey's is used for qualitative data, and for the quantitative, and quadratic linear models are preferred.

Potato is the world's most important non-cereal food crop, and therefore, it is considered one of the major food sources for humankind. Its conventional propagation is asexual, by using the tuber, which allows the accumulation and dissemination of pathogens to new cultivation areas. This fact not only impairs the yield of this solanaceous plant, but also threatens the maintenance of genotypes for commercial or breeding purposes. Due to the impossibility of using botanical seed, conservation and exchange of germplasm of this species by means of conventional methods are not feasible. In all potato-producing regions, the demand for high-quality tubers has been paramount to ensure crops production. Thus, biotechnological techniques based on tissue culture are very important. Plant tissue culture offers alternative methods of propagation by in vitro techniques that provide production and multiplication of material with high sanity. Thus, this literature review summarizes the history and current situation of tissue culture techniques applied to potato crop. Besides clonal multiplication, this biotechnological tool makes available initial indexed material to breeding programs and certified seed potato, and facilitates the exchange and conservation of germplasm. For all these reasons, the use of these techniques in potato production chain directly benefits producers by providing high-quality propagules.

Savannah is the second biome in biodiversity in Brazil, presenting great vegetation endemism. Baruzeiro (Dipteryx alata Vog.), native from this biome, is an economically important species, with an incipient market due to the lack of commercial plantations. This highlights the need to develop and provide the basis for the domestication of this species. Thus, this study evaluated different concentrations of MS medium, using baruzeiro intact or cut seeds for in vitro establishment. Seeds from baruzeiro ripe fruits were decontaminated and were left intact or partially cut; subsequently, the seeds were inoculated into flasks with different concentrations of MS culture medium. The experimental design was completely randomized as a 5 x 2 factorial, consisting of 5 MS medium concentrations (0, 25, 50, 75 or 100%) and 2 types of seeds (intact or partially cut seeds), with three replications. Each experimental unit consisted of five flasks and 10 plants. After five months of incubation, the contamination of explants, seed germination, the number of fully developed plants and the dry masses of shoot and root of baruzeiros were evaluated. Intact seeds provided better results for all characteristics evaluated. The increased concentration of MS medium resulted in mass gain of plants; however, the use of MS medium 0% provided greater percentage of fully developed plants, the most interesting feature for baruzeiro in vitro establishment.

The study determined the quality parameters of three cultivars of strawberries, aiming to provide support to the producers as to the choice of the best cultivar at planting time. The studied parameters were: physical characterization, mass loss, pH, soluble solids, titratable acidity, total, reducing and non-reducing sugars and vitamin C. Fruit of the cv. Oso-Grande presented higher values of pH and mass loss and lower values of titratable acidity, soluble solids, total and reducing sugars and vitamin C, presenting a good quality and can thus be used by producers. The study determined the quality parameters of three cultivars of strawberries, aiming to provide support to the producers as to the choice of the best cultivar at planting time. The studied parameters were: physical characterization, mass loss, pH, soluble solids, titratable acidity, total, reducing and non-reducing sugars and vitamin C. Fruit of the cv. Oso-Grande presented higher values of pH and mass loss and lower values of titratable acidity, soluble solids, total and reducing sugars and vitamin C, presenting a good quality and can thus be used by producers.

Research about structural and physiological modifications inherent to the acclimatization process is fundamental to understand this phase. The objective of this work was evaluating different sources of silicon in the in vitro cultivation of the ‘Grande Naine’ banana plants on the biochemical, phytotechnical and ultrastructural characteristics during the acclimatization process. For such, banana tree plantlets already established in vitro were inoculated in Murashige & Skoog medium (MS) with the addition of 30 g L-1 of sucrose, 1 mg L-1 of ANA (naftalenoacetic acid) and solidified with 1,8 g L-1 of PhytagelTM. Three sources of silicate added to the MS medium, namely sodium silicate, potassium silicate and calcium silicate at the dosage of 1 g L-1 and to the MS medium without silicate as a control were tested. Elapsed 45 days from the in vitro rooting, the plants were kept in a greenhouse for 60 days. The experimental design was completely randomized. The use of silicon in vitro cultivation is beneficial for providing better photosynthetic apparatus, higher content of cellulose and hemicellulose during acclimatization of banana plants. The acclimatization process is essential because it provides an increase in epicuticular wax layer on leaves of ‘Grand Naine’ banana plants. Pesquisas acerca das modificações estruturais e fisiológicas inerentes ao processo de aclimatização são fundamentais para compreender esta fase. Assim, o objetivo deste trabalho foi avaliar diferentes fontes de silício no cultivo in vitro de bananeira ‘Grande Naine’ sobre características bioquímicas, fitotécnicas e ultraestruturais, durante o processo de aclimatização. Para tanto, brotos de bananeira já estabelecidos in vitro foram inoculados em meio Murashige & Skoog (MS), com adição de 30 g L-1 de sacarose, 1 mg L-1 de ANA (ácido naftalenoacético) e solidificado com 1,8 g L-1 de PhytagelTM. Foram testadas três fontes de silicato acrescidas ao meio MS, silicato de sódio, silicato de potássio e silicato de cálcio, na dosagem de 1 g L-1 e o meio MS sem silicato como testemunha. Decorridos 45 dias do enraizamento in vitro, as plantas foram mantidas em casa de vegetação por 60 dias. O delineamento experimental foi inteiramente casualizado. O uso do silício no cultivo in vitro é benéfico por proporcionar melhor aparato fotossintético, maiores conteúdos de celulose e hemicelulose durante a aclimatização de plantas de bananeira. O processo de aclimatização é fundamental, pois proporciona aumento na camada de cera epicuticular em folhas de bananeira ‘Grande Naine’.

Dipteryx alata Vog. (barueiro) is a native fruit of the Cerrado used in food and medicine. The species has never been domesticated and is currently at risk of extinction. Plant tissue culture is an important tool for the conservation of germplasm and for quick, large-scale propagation of quality seedlings. While, this technique has never been used with barueiro, it could be a valuable tool in the domestication of this species. The objective of this work is to evaluate concentrations of MS medium salts (25, 50, 75 and 100%) supplemented with coconut water (100 mL L-1), dwarf banana pulp (60 g L-1) or the absence of any supplement in the in vitro establishment of barueiro seeds (Dipteryx alata Vog). The experiment used a completely randomized design (CRD) with a 3x4 factorial scheme (three cultivation media types and four concentrations of MS salts) and three repetitions. The following characteristics were evaluated: germination rate , shoot length , largest root length , stem diameter , number of leaves , chlorophyll A , chlorophyll B , total chlorophyll , and the fresh and dry mass of the seedlings. The coconut water and banana pulp supplements did not improve the in vitro development of the barueiro seedlings and the full concentration of MS salts did not improve the initial development of the seedlings. However, the pure MS medium at a concentration of 25% MS salts was the best option for the in vitro establishment of Dipteyx alata.

O objetivo deste trabalho foi avaliar o efeito de diferentes fontes de silício durante a fase de enraizamento in vitro de bananeira 'Maçã' por meio de análise fisiológica, fitotécnica e ultraestrutural. Foram utilizados propágulos já estabelecidos in vitro e inoculados em meio MURASHIGE & SKOOG (MS), adicionado de 30g L-1 de sacarose, 1mg L-1 de ANA (ácido naftalenoacético) e solidificado com 1,8g L-1 de PhytagelTM. Foram testadas três fontes de silicato acrescidas ao meio MS, silicato de sódio, silicato de potássio e silicato de cálcio, na dosagem de 1g L-1 e o meio MS sem silicato como testemunha. O delineamento experimental foi o inteiramente casualizado, com quinze repetições. Os propágulos foram mantidos por 45 dias em sala de crescimento, sob condições controladas. Verificou-se aumento nos teores de clorofila a, b e total na presença de silicato de cálcio. A suplementação do meio de cultura com silicato de sódio promoveu aumento de comprimento, massa fresca e seca de parte aérea. O silício proporciona adequado desenvolvimento das plântulas.The objective of the research was to evaluate the effect of different sources of silicon during the in vitro rooting phase of 'Maçã' banana tree by means of physiological, phytotechnical and ultrastructural analysis. It was used propagules already established in vitro which were inoculated in MURASHIGE & SKOOG (MS) medium, added of 30g L-1 of sucrose, 1mg L-1 of NAA (naphthalene acetic acid) and solidified with 1.8g L-1 of PhytagelTM. It was tested three sources of silicate added to MS medium, sodium silicate, potassium silicate and calcium silicate, at a dose of 1g L-1 and MS medium without silicate as a witness. The experimental design was completely randomized with fifteen replicates. The propagules were kept for 45 days in a growth room under controlled conditions. There was an increase in levels of chlorophyll a, b and total in the presence of calcium silicate. Supplementation of culture medium with sodium silicate promoted increase in length, fresh and dry weight of shoots. The silicon provides adequate seedling development.

A lichia (Litchi chinensis Sonn.) é um fruto subtropical de alto potencial comercial devido ao seu sabor levemente acidificado, excelente aroma, alto valor nutritivo e atrativa cor vermelha da casca. Ainda no campo, a cor da casca altera-se facilmente, tornando-se escurecida em resposta a estresses (alterações da umidade relativa e ataque de patógenos). Após colhida, a casca da lichia perde rapidamente sua cor vermelha. O escurecimento da casca tem sido atribuído a rápida degradação da antocianina, assim como: à rápida perda de umidade pelo fruto e à atividade de enzimas oxidativas como polifenoloxidases e peroxidases. Dada essa alta perecibilidade, o controle do escurecimento é fundamental para o aumento na vida útil pós-colheita, visando ao mercado interno e à exportação de frutas. Avaliou-se, neste trabalho, o comportamento pós-colheita de lichias da cv. Bengal quanto ao escurecimento da casca e às modificações relacionadas com a qualidade da polpa de lichias submetidas a diferentes embalagens: bandeja recoberta com filme de polietileno de baixa densidade com e sem perfurações e frutos recobertos com película de fécula de mandioca (3%). Os frutos foram mantidos em temperatura ambiente (25,1ºC±1,5ºC; 69,3%±8,62%UR) e armazenados por seis dias. Foram realizadas análises físicas, químicas e bioquímicas no dia 0 e a cada 2 dias, até osexto dia de armazenamento. A embalagem recoberta com filme de polietileno perfurado apresentou-se eficiente na redução da perda de massa, escurecimento da casca e na manutenção do teor de antocianina da casca de lichias durante seis dias de armazenamento, em temperatura ambiente.Lychee is a subtropical fruit of high commercial value, due to its slightly acid taste, excellent aroma, high nutritive value and attractive deep bright red color of its peel. Also in the field, skin color changes easily, becoming dark in response to stress (changes in relative humidity and the incidence of pathogens). Harvested lychee fruit rapidly loses its bright red skin colour. Peel browning of harvested lychee has largely been attributed to the rapid degradation of the anthocyanin pigments as well as the rapid loss of moisture from the fruit and the activity of oxidative enzymes such polyphenoloxidase and peroxidases. Due to it high perishability, browning control is a fundamental process to the increase of post-harvest useful life aiming the home market and fruit exportation. This study evaluated the postharvest behavior of Litchi cv. Bengal fruits regarding pericarp browning and changes on lychee fruits pulp quality when different packing is applied: plastic trays covered with parafilm or solely parafilm, and fruits covered with cassava starch film (3%). Lychee fruits were stored for six days at room temperature (25.1ºC±1.5; 69.3%UR). Physical, chemical and biochemical analyses were performed on day 0 and on every two days till the end of the storage period. The package covered with perforated polyethylene film was efficient in reducing weight loss, skin browning and maintenance of the anthocyanin content of the bark of leeches for six days of storage at room temperature.

O mamão é um fruto climatérico cujas transformações resultantes do amadurecimento ocorrem rapidamente após a colheita do fruto fisiologicamente maduro, desencadeadas pela produção do etileno e aumento da taxa respiratória. Isso o caracteriza como um fruto bastante perecível após a colheita. Dada essa alta perecibilidade, o controle do amadurecimento é fundamental para o aumento na vida útil pós-colheita, visando ao mercado interno e à exportação de frutas. O composto 1-metilciclopropeno (1-MCP) vem sendo usado com a finalidade de controlar o amadurecimento de frutos, flores e hortaliças. Neste trabalho foi avaliada a ação do tratamento com 1-MCP, em diferentes tempos de exposição, em mamões armazenados em condições ambiente. Os frutos foram colhidos no estádio 1 de maturação e foram submetidos ao 1-MCP, na concentração de 270 nL/L, por um período de 0, 12, 18 e 24 horas e, em seguida, armazenados em condição ambiente (T 22±2°C/UR 77% ±2%), por 8 dias. Os frutos tratados com 1-MCP apresentaram maior firmeza, menores teores de pectina solúvel e menor atividade de enzima PME mostrando que o 1-MCP foi eficiente em retardar o amaciamento dos frutos no período estudado.The papaya is a climateric fruit whose transformations resulting from ripening occur shortly after the picking of the physiologically ripe fruit, triggered by the production of ethylene and increased breathing rate. That makes it a quite perishable fruit after harvest. Given that perishability, ripening control is fundamental to increase post-harvest shelf life, both for internal consumption and exports. The compound 1-methylcyclopropene (1-MCP) has been used with the purpose of controlling the ripening of fruits, flowers and vegetables. In this work, the effect of the treatment with 1-MCP on papayas stored under room conditions was evaluated in different exposure periods. The fruits were picked at stage 1 of maturation and were submitted to 1-MCP, at the concentration of 270 nL/L, for a period of 0, 12, 18 and 24 hours, and then stored under room conditions (T 22±2°C/RH 77% ±2%) for 8 days. The 1-MCP-treated fruits showed increased firmness, lower contents of soluble pectin and less activity of PME enzyme, showing that 1-MCP was effective in delaying the softening of the fruits over the studied period.

O objetivo deste trabalho foi verificar a qualidade de mangas da cv. Palmer tratadas com 1-metilciclopropeno (1-MCP) mantidas sob armazenamento refrigerado e sob armazenamento refrigerado associado à exposição à temperatura ambiente por quatro dias. O delineamento experimental foi inteiramente casualizado, em fatorial 3 x 6, sendo 3 níveis do fator dose de 1-MCP (0 -testemunha, 100 nL.L-1 e 150 nL.L-1) e 6 níveis do fator tempo de armazenamento (0; 7; 14; 21; 28 e 35 dias de armazenamento refrigerado, no experimento 1, e 0; 7 + 4; 14 + 4; 21 + 4; 28 + 4 e 35 dias de armazenamento refrigerado + 4 dias sob condição ambiente, no experimento 2), com 3 repetições. Cada parcela experimental foi composta por 2 frutos. O uso de 1-MCP em mangas 'Palmer' mantidas sob refrigeração reduz as perdas de massa e ácido ascórbico, retardando, mas não impedindo o amadurecimento. O tratamento com 150 nL.L-1 não é mais eficiente que o com 100 nL.L-1, pelas características químicas analisadas. As mangas 'Palmer' expostas à condição ambiente por quatro dias apresentam expressivo murchamento e perda de qualidade, com base nas análises de sólidos solúveis, açúcares solúveis e acidez titulável.The objective of this work was to verify the behavior of mangoes cv. Palmer treated with 1-methylcyclopropene (1-MCP) stored under refrigeration and under refrigeration associate in exposure for four days at room temperature. The experiment was carried out in a completely randomly design, 3 x 6 factorial, with 3 levels of the factor concentration of 1-methylcyclopropene (0 nL.L-1- witness, 100 nL.L-1 and 150 nL.L-1) and 6 levels of the factor period of storage (0, 7, 14, 21, 28 and 35 days of cool storage, on the set up 1, and 0, 7 + 4, 14 + 4, 21 + 4, 28 + 4 and 35 days of cool storage + 4 days of room storage, on the set up 2), with 3 replicates. The experimental units were built up with 2 fruits. The use of 1-methylcyclopropene on the fruit kept under refrigeration reduces the weight and ascorbic acid losses, delaying but not avoiding the ripening. The treatment with 150 nL.L-1 is not more efficient than that with 100 nL.L-1, in accord to the analysed chemical characteristics. The increased weight loss of fruits stored under environmental conditions promoted expressive shriveling and loss of quality, on the basis of analyses of soluble solids, soluble sugars and titratable acidity.

Objetivou-se, neste trabalho, avaliar as modificações da poligalacturonase (PG) e da pectinametilesterase (PME) em morangos cultivados na região de Lavras, MG, e armazenados em temperatura ambiente. Foram utilizados morangos das cultivares 'Oso-grande', 'Toyorrinho' e 'Tudla'. Utilizou-se o delineamento inteiramente casualizado com 4 repetições, sendo os tratamentos arranjados em esquema fatorial (3X2), sendo 3 cultivares e 2 dias de análises (0 e 5 dias). A parcela experimental foi constituída por 10 frutos. Durante o armazenamento houve uma diminuição nos teores de pectina total e um aumento nos de pectina solúvel em todas as variedades analisadas. A atividade da PG e PME aumentaram com o período de armazenamento, independente da cultivar.The objective of this research was to evaluate the modifications of the polygalacturonase (PG) and the pectinmethilesterase (PME) in strawberries cultivated in the region of Lavras, MG, and stored at room temperature. Strawberries of the research were used for plantation of 'Oso-grande', 'Toyorrinho' and 'Tudla'. The entirely randomized design with 4 replicates was used, being the treatments arranged in factorial (3x2), being 3 plantations and 2 days of analyses (0 and 5 days). The experimental parcel was consisted by 10 fruits. During the storage there was a reduction in the levels of total pectin and an increase in the ones of soluble pectin in all the analyzed varieties. With the period of storage the PG and PME activity grew, independent of the cultivar.

O objetivo do trabalho foi avaliar o efeito do 1-MCP na firmeza de mangas ´Palmer', armazenadas sob refrigeração. As mangas foram tratadas com 1-MCP nas concentrações de 0, 100 e 150nL.L-1, durante 12 horas à 22ºC. Em seguida, foram armazenadas em câmara fria a 10 ± 1ºC e 80 a 90% de UR, por um período de 35 dias. A cada 7 dias foram retirados 6 frutos de cada tratamento para as seguintes avaliações: firmeza, pectina total, percentagem de solubilização de pectinas, atividade da pectinametilesterase, poligalacturonase e â-D-galactosidase. O tratamento com 1-MCP, associado à refrigeração mostrou ser eficiente em prolongar a vida útil dos frutos. Os frutos tratados com 150nL.L-1 apresentaram menor percentagem de solubilização de pectina e mais firmes no final do armazenamento, quando comparados aos outros tratamentos. Após 35 dias de armazenamento refrigerado, todos os frutos estavam aptos para o consumo, indicando que outros estudos deverão ser realizados aumentando o tempo de armazenamento.The objective of this work was to evaluate the effect of the 1-MCP in the firmness of mangos ´Palmer' stored under refrigeration. The mangos were treated with 1-MCP in concentrations of 0, 100 and 150nL.L-1, during 12 hours at the 22ºC. Soon after, they were stored in a cold chamber (10 ± 1ºC and 80 to 90% of UR), for a period of 35 days. Every 7 days were retired 6 fruits of each treatment for to the following evaluations: firmness, total pectin, percentage of solubilization of pectins, activity of the pectinmethylesterase, polygalacturonase and â-D-galactosidase activities. The treatment with 1-MCP, associated to the refrigeration showed to be efficient in prolonging the useful life of the fruits. The treated fruits with 150nL.L-1 presented smaller percentage of pectin solubilization and firmness in the end of the storage, when compared to the other treatments. After 35 days of refrigerated storage, all the fruits were capable for the consumption, indicating that other studies should be accomplished increasing the time of storage.

No Brasil, o consumo de pêssegos in natura vem aumentando a cada ano. No entanto, durante o transporte, o período de armazenamento e a comercialização, as perdas são bastante significativas, havendo a necessidade de desenvolver tecnologias para manter a qualidade pós-colheita e prolongar a vida útil desses frutos. O composto 1-metilciclopropeno (1-MCP) vem sendo usado com resultados positivos em diversos tipos de frutos, como goiaba, banana, maçã, entre outras. Neste trabalho, foi avaliado o tratamento com 1-MCP em pêssegos armazenados em condições ambientais para a manutenção da firmeza dos frutos. Os frutos da cv. Diamante foram provenientes do município de Nepomuceno-MG, colhidos no estádio de maturação 'de vez' e selecionados em função do tamanho, estádio de maturação e ausência de injúrias. Os frutos foram submetidos à imersão em hipoclorito de sódio a 1% para desinfecção e parte deles foi tratada com 1-MCP, na concentração aproximada de 625 nL/L, por 12 horas. Em seguida, os frutos foram armazenados por até 10 dias, em temperatura ambiente (22 ± 2°C e 77 ± 2% UR). Foram realizadas análises de firmeza da polpa, solubilização de pectinas e atividades de pectinametilesterase e poligalacturonase a cada 2 dias até o final do período de armazenamento. Os frutos tratados com 1-MCP apresentaram maior firmeza e menor solubilização de pectinas durante o período avaliado e também menor atividade de pectinametilesterase que os frutos-controle até o 6º dia de armazenamento, demonstrando que o 1-MCP foi eficiente em retardar o amaciamento dos frutos no período estudado.In Brazil, the consumption of in natura peaches has been increasing every year. However, during the transport, the storage period and the commercialization, the losses are quite significant, having the need to develop technologies to maintain postharvest quality and to prolong the useful life of those fruits. The compound 1-methylcyclopropene (1-MCP) has been used with positive results in several types of fruits as guava, banana, apple, among others. In this work, the isolated action of the treatment with 1-MCP was evaluated in peaches stored under environment conditions for the maintenance of firmness of fruits. The fruits cv. Diamante were from Nepomuceno - MG, Brazil, picked at the maturation stadium 'just before ripening' and selected in function of the size, maturation stadium and absence of injuries. The fruits were submitted to immersion in 1% sodium hypochlorite for disinfection and part of them were treated with 1-MCP, at the concentration of approximate 625 nL/L, per 12 hours. Soon after, the fruits were stored for up to 10 days, at environment temperature (22 ± 2°C and 77 ± 2% UR). It was realized analyses of pulp firmness, solubilization of pectins and pectinmethylesterase activities and polygalacturonase every 2 days, untill the end of the storage period. The fruits treated with 1-MCP presented greater firmness and smaller solubilization of pectins during the appraised period, and also smaller pectinmethylesterase activity that the fruits control until the 6th day of storage, showing that 1-MCP was efficient in delaying the softening of fruits at the studied period.