Seed longevity differs in Astronium fraxinifolium Schott from two geographic regions in Brazil

Abstract

The objective of this work was to evaluate the longevity of Astronium fraxinifolium Schott seeds collected in the states of Goiás and Minas Gerais in Brazil and analyse its association with local weather conditions during the vegetative and reproductive phases (temperature, precipitation and altitude) and seed oil content. Longevity was tested in a controlled ageing test at a constant temperature of 45 °C and relative humidity (RH) of 60, 65 or 70%, followed by germination. Seed longevity was inferior in seeds collected in the state of Minas Gerais and superior in seeds collected in the state of Goiás. There was a significant positive correlation between seed longevity and temperature and a significant negative correlation between seed longevity and altitude. No correlation was found between rainfall and seed longevity. In addition, we found a significant negative correlation between seed longevity and oil content, which was associated with an increase in malondialdehyde (MDA) content. Thus, the influence of the maternal environment during seed production should be considered during seed collection for improved ex situ conservation of A. fraxinifolium seeds.A longevidade de sementes difere em Astronium fraxinifolium Schott de duas regiões geográficas do Brasil RESUMO: O objetivo deste trabalho foi avaliar a longevidade de sementes de Astronium fraxinifolium Schott coletadas nos estados de Goiás e Minas Gerais, no Brasil, e analisar a associação com as condições climáticas locais (temperatura, precipitação e altitude) e teor de óleo da semente. A longevidade foi testada através de um teste de envelhecimento controlado a uma temperatura constante de 45 °C e umidade relativa (UR) de 60, 65 e 70%, seguido de germinação. A longevidade das sementes foi inferior nas sementes coletadas no Estado de Minas Gerais e superior nas sementes coletadas no Estado de Goiás. Houve correlação significativa e positiva da longevidade das sementes com a temperatura e correlação significativa e negativa com a altitude. Não foi encontrada correlação entre a precipitação e a longevidade das sementes. Além disso, encontramos uma correlação significativa e negativa da longevidade das sementes e do teor de óleo, que foi associada a um aumento no conteúdo de malonaldeído (MDA). Assim, a influência do ambiente materno durante a produção de sementes pode ser considerada durante a coleta de sementes para melhor conservação ex situ de sementes de A. fraxinifolium.Palavras-chave: conservação ex situ; precipitação; armazenamento de sementes; temperatura Seed longevity differs in Astronium fraxinifolium Schott from two geographic regions in Brazil Rev. Bras.

Comparative Seeds Storage Transcriptome Analysis of Astronium fraxinifolium Schott, a Threatened Tree Species from Brazil

“…Seed samples were obtained in 2013 from two mother trees of Cerrado biome at Goiás (coordinates 14 [101], these two accessions were selected based on their longevity, which were high for GOIAS and low for MINAS. Aged and control seeds were used for both accessions (Figure 1).…”

“…Embryonic axes were extracted from control and artificially aged seed after 21 days (temperature of 45 • C and RH of 60%) according to [101]. Briefly, the viability data were transformed into probit units for sigma and P 50 calculations [102].…”

“…Prior germination tests established 30 • C as the optimal germination temperature. The embryonic axes extracted from seeds without protruded radicles after 20 h imbibition were immersed in liquid nitrogen and stored at −80 • C until conducting the RNA extraction [101].…”