Alterações fisiológicas, nutricionais e bioquímicas em sementes de pimentão, com frutos em diferentes estádios de maturação e do repouso pós-colheita
Carregando...
Data
2019-06-17
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Em pimentão a floração e a frutificação são contínuas, o que faz com que a planta tenha frutos e sementes em diferentes estádios de maturação. Dessa forma, identificar o estádio em que as sementes alcançam a maturidade fisiológica é fundamental para a determinação do momento ideal de colheita dos frutos. Diante do exposto, objetivou-se com este trabalho estudar o efeito do estádio de maturação e do repouso pós-colheita dos frutos na qualidade fisiológica, na resposta bioquímica e na composição química de sementes de pimentão. O trabalho foi dividido em dois capítulos, em ambos o delineamento experimental utilizado foi de blocos casualizados, com oito tratamentos, resultantes de um fatorial 4x2, com quatro repetições. O primeiro fator foi constituído de quatro estádios de maturação (35, 50, 65 e 80 dias após a antese (DAA)) e o segundo, sem e com o repouso dos frutos pós-colheita, por 7 dias. Foram avaliados dois genótipos que apresentam padrão de qualidade visual de sementes diferentes, ou seja, sem (1730) e com (190-2) o escurecimento do tegumento das sementes. No primeiro capítulo as características avaliadas nas sementes foram a determinação do teor de água, massa de mil sementes, germinação, vigor (primeira contagem do teste de germinação e índice de velocidade de germinação), atividade das enzimas superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD), a peroxidação lipídica (LIP) e o teor de peróxido de hidrogênio (H2O2). No segundo capítulo foram avaliados nas sementes a massa seca de mil sementes, os teores de macronutrientes e proteínas. A melhor época para a colheita dos frutos para semente do genótipo 1730 sem e com o repouso pós-colheita dos frutos é por volta dos 80 DAA e para o genótipo 190-2 sem o repouso dos frutos é aos 72 DAA e com o repouso, aos 58 DAA. Nesses estádios de maturação as sementes apresentam máxima germinação e vigor. O repouso pós-colheita dos frutos proporcionou maior qualidade fisiológica para os dois genótipos, assim como maior massa de mil sementes. As atividades das enzimas SOD e CAT de ambos os genótipos, sem e com o repouso pós-colheita dos frutos, foram altas aos 35 DAA, em função da elevada peroxidação lipídica, reduzindo até aos 65 DAA. Houve redução dos teores de K, Ca e Mg e aumento do teor das proteínas albumina, globulina e prolaminas em função do estádio de maturação dos frutos. O repouso pós-colheita dos frutos proporcionou maior teor de Ca e da proteína albumina. A ordem decrescente dos teores de macronutrientes e proteínas nas sementes dos dois genótipos foi sempre a mesma, independentemente do estádio de maturação e do repouso pós-colheita dos frutos: N>K>P>Mg>S>Ca e albumina>globulina≈glutelina>prolamina, respectivamente.
In sweet pepper the flowering and the fruiting are continuous, which causes that the plant has fruits and seeds in different stages of maturation. Thus, to identify the stage in which the seeds reach the physiological maturity is fundamental to determine the ideal moment to harvest the fruits. In view of this, the objective of this work was to study the effect of maturation stage and post-harvest rest of the fruits in physiological quality, biochemical response and chemical composition in pepper seeds. The work was divided in two chapters, in both the experimental design was randomized blocks, with eight treatments, resulting from a 4x2 factorial, with four replications. The first factor consisted of four maturation stages (35, 50, 65 and 80 days after anthesis (DAA)) and the second, without and with the post-harvest rest, for 7 days. Two genotypes with different seed quality standards were evaluated, that is, without (1730) and with (190- 2) darkening of seed integument. In the first chapter the characteristics evaluated in the seeds were the determination of the content of moisture, weight of a thousand seeds, germination, vigor (first germination test count and germination velocity index), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) enzyme activity, lipid peroxidation (LIP) and hydrogen peroxide content (H2O2).In the second chapter were evaluated the dry mass of one thousand seeds, the macronutrient and protein contents in the seeds.The fruit harvest time indicated for seeds of genotype 1730 without and with the rest of the fruits is around 80 DAA and for the 190-2 genotype without the rest of the fruits it is at 72 DAA and with rest at 58 DAA. In these stages of maturation, the seeds present maximum germination and vigor. The post-harvest rest of the fruits provided higher physiological quality for the two genotypes, as well as a higher weight of one thousand seeds. The activity of the SOD and CAT enzymes of both genotypes, without and with the post-harvest rest of the fruits, were high at 35 DAA, due to high lipid peroxidation and reduced up to 65 DAA. There were reductions of K, Ca and Mg contents and increase of the protein content of albumin, globulin and prolamins as a function of the maturation stage of the fruits. The post-harvest rest of fruits provided higher Ca content and protein albumin. The decreasing order of the macronutrient and protein contents in the seeds of the two genotypes was always the same, independently of maturation stage and post-harvest rest of the fruits: N> K> P> Mg> S> Ca and albumin> globulin gluteline> prolamine, respectively.
In sweet pepper the flowering and the fruiting are continuous, which causes that the plant has fruits and seeds in different stages of maturation. Thus, to identify the stage in which the seeds reach the physiological maturity is fundamental to determine the ideal moment to harvest the fruits. In view of this, the objective of this work was to study the effect of maturation stage and post-harvest rest of the fruits in physiological quality, biochemical response and chemical composition in pepper seeds. The work was divided in two chapters, in both the experimental design was randomized blocks, with eight treatments, resulting from a 4x2 factorial, with four replications. The first factor consisted of four maturation stages (35, 50, 65 and 80 days after anthesis (DAA)) and the second, without and with the post-harvest rest, for 7 days. Two genotypes with different seed quality standards were evaluated, that is, without (1730) and with (190- 2) darkening of seed integument. In the first chapter the characteristics evaluated in the seeds were the determination of the content of moisture, weight of a thousand seeds, germination, vigor (first germination test count and germination velocity index), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) enzyme activity, lipid peroxidation (LIP) and hydrogen peroxide content (H2O2).In the second chapter were evaluated the dry mass of one thousand seeds, the macronutrient and protein contents in the seeds.The fruit harvest time indicated for seeds of genotype 1730 without and with the rest of the fruits is around 80 DAA and for the 190-2 genotype without the rest of the fruits it is at 72 DAA and with rest at 58 DAA. In these stages of maturation, the seeds present maximum germination and vigor. The post-harvest rest of the fruits provided higher physiological quality for the two genotypes, as well as a higher weight of one thousand seeds. The activity of the SOD and CAT enzymes of both genotypes, without and with the post-harvest rest of the fruits, were high at 35 DAA, due to high lipid peroxidation and reduced up to 65 DAA. There were reductions of K, Ca and Mg contents and increase of the protein content of albumin, globulin and prolamins as a function of the maturation stage of the fruits. The post-harvest rest of fruits provided higher Ca content and protein albumin. The decreasing order of the macronutrient and protein contents in the seeds of the two genotypes was always the same, independently of maturation stage and post-harvest rest of the fruits: N> K> P> Mg> S> Ca and albumin> globulin gluteline> prolamine, respectively.
Descrição
Palavras-chave
Capsicum annuum L., Germinação, Vigor, Antioxidantes, Integridade de membranas, Macronutrientes, Proteínas