Influence of temperature on the germination and root size of Acmella oleracea (L.) R. K. Jansen

Abstract

Acmella oleracea is a herbaceous plant native to the Amazon region that is currently arousing industrial interest due to its potential gastronomic, cosmetic and pharmaceutical uses. Accordingly, the objective of the current study was to test the influence of temperatures on A. oleracea seed germination and seedling vigor. A completely randomized design (CRD) with five treatments and five replicates was used. Treatments consisted of temperatures: 23, 26, 29, 32 and 35 ºC. The study was conducted in BODtype climate chambers with relative humidity above 90% and a 12 h photoperiod. Germination, germination speed index (GSI), average germination time, root length and number of normal and abnormal seedlings were recorded. Temperature influenced all analyzed variables, except average germination time and number of normal/abnormal seedlings. A quadratic model best described the relationship between dependent and independent variables. In general, maximum germination values, and GSI and root lengths were obtained at temperatures close to 29 °C, while the lowest observed values for these variables occurred at extreme temperatures (23 and 35 °C). The highest percentage of germinated seeds occurred on the second day. Temperatures above 29 ºC induced a significant reduction in the A. oleracea seedling root lengths.

The cultivation environment influences the physiological quality of stored Sonchus oleraceus L. seeds

“…According to Gordin et al (2014), the decrease in temperature tends to reduce the speed of seed germination, due to the effects on the speed of imbibition and mobilization of reserves. On the other hand, increasing the temperature up to a certain limit (optimal temperature) can make the germination process faster and more homogeneous (Silva et al, 2020).…”

Crescimento e produção do jambu submetido a lâminas de irrigação

“…Americana (Lactuca sativa L.). No entanto, deve-se ter cuidado com o excesso de água, visto que as hortaliças apresentam sensibilidade ao encharcamento do solo, conforme observado por Silva & Queiroz (2013), cujo trabalho mostrou que a cultura da alface apresentou reduções na altura, diâmetro do caule e no acúmulo de biomassa sob estresse por excesso hídrico. Assim, tais resultados demonstram que o desempenho das culturas frente a disponibilidade hídrica depende do material genético, condições edafoclimáticas, bem como do sistema de cultivo adotado.…”

“…Essa hortaliça representa importante fonte de renda para os pequenos produtores dos municípios do Estado do Pará (Homma et al, 2014). Ela também está presente em outros estados da Região Norte, como o Acre, Amazonas e Amapá (Silva et al, 2020).…”