RESUMO
Aims: An experiment was conducted to examine the effect of various concentrations of melatonin on post harvest weight loss and shelf life of three traditional banana varieties viz. Ney Poovan, Nendran and Red Banana.Study Design: Completely Randomized Design.Place and Duration of Study: Post Graduate laboratory, Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore during 2022.Methodology: Banana hands were dipped in 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mM melatonin for 15 minutes and were stored at ambient temperature. The hands dipped in water were treated as control. Observations on physiological weight loss and shelf life were recorded till the fruits remained marketable.Results: The results depicted that fruits immersed in 1.0 and 1.5 mM melatonin for 15 minutes recorded lower weight loss (31.56, 30.55 and 24.90%) on 11th, 11th and 12th day of storage and longer shelf life by 3, 2.67 and 2.67 days in Ney Poovan, Nendran and Red Banana respectively.Conclusion: The effects of melatonin were due to its efficiency in reducing transpiration and respiration and thereby lowering weight loss. The lowered metabolic activity not only mitigated weight loss but also maintained firmness and turgidity of the fruits and thereby prolonging the storability. It was evident from the results that melatonin treatment could be a good practice for extending postharvest life of banana by reducing the physiological loss in weight simultaneously maintaining the appearance.
RESUMO
Os objetivos deste trabalho foram avaliar a qualidade física, fisiológica e sanitária de sementes de 17 variedades de milho crioulo antes e após armazenagem em garrafas PET e comparar os resultados aos padrões já estabelecidos para comercialização de cultivares comerciais de milho. Foram realizados os testes de pureza física, retenção de peneiras, massa de 1000 sementes, grau de umidade, germinação, emergência em canteiro, índices de velocidade de germinação e emergência das sementes, além de exame de sementes infestadas. Pelos resultados obtidos, é possível concluir que as sementes de milho crioulo das diferentes variedades apresentam alta porcentagem de pureza física e germinação mesmo após o armazenamento, com valores acima dos padrões mínimos exigidos para comercialização de sementes de milho (98 e 85 por cento, respectivamente). O grau de umidade das sementes das diferentes variedades de milho crioulo antes e após o armazenamento permaneceu abaixo de 13 por cento, destacando-se a aptidão da região norte de Minas Gerais para a produção e conservação de sementes de qualidade. Três variedades apresentaram porcentagem de infestação superior ao padrão máximo recomendado (3 por cento), sendo, portanto, necessário aprimorar o controle de pragas de grãos armazenados. São necessárias melhorias para uniformização de classificação das sementes por peneiras, já que as amostras de três variedades não alcançaram o padrão mínimo de 94 por cento em uma mesma peneira, exigido pela legislação.
The objective of this research was to evaluate the physical, physiological and sanitary quality of corn seeds of 17 maize varieties (landraces) before and after storage in PET bottles. The seeds were submitted to the following tests: physical purity, retention on sieves, weight of 1000 seeds, germination, seed moisture content, emergence in flowerbed, infested seed exam and seed health (deep-freezing method). Germination and emergence velocity index were determined. Maize landraces seeds of different varieties presented a great percentage of physical purity and germination, which were over the minimum standards values required for commercialization of corn seeds (98 and 85 percent, respectively), even after storage. Seed moisture content remained below 13 percent before and after storage, standing out the potential of Nothern Minas Gerais for production and conservation of high-quality seeds. Three varieties presented infestation higher than the maximum values accepted for corn seeds commercialization (3 percent), indicating the need of better pests control during storage. Samples of three varieties have not reached satisfy standard values of retention on the same sieve (94 percent), indicating the need of better standardization on size classification of some seed lots.