Accelerated aging of ipê seeds under controlled conditions of storage

Abstract

-This research was aimed at studying effects of storage and accelerated aging on germination and profile of storage proteins in Handroanthus albus seeds. These were stored into a cold chamber (± 8 o C; RH ± 40%) and after periods of 0, 3, 6, 9, and 12 months of storage, were subjected to accelerated aging for 0, 24, 48, 72, and 96 hours. Relationships between germination and proteins profile were assessed. Germination test was performed at 25 °C, under constant light. For protein extraction, 125 mg of seeds were macerated in 2 mL of extraction buffer (1M TrisHCl; pH 8.8) and applied to SDS-PAGE polyacrylamide gel at 80 V .15 h -1 . Twelve month storage, combined with 72 hours accelerated aging have increased germination in approximately 65% when compared to non-aged seeds or to seeds with 24 h of accelerated aging. Besides beneficial effects, degradation and synthesis of different proteins were observed. It was concluded that germination of Handroanthus albus seeds, when not subjected to accelerated aging, is favored by storage in cold chamber during three to six months, or from nine to 12 months when subjected to accelerated aging process. Storage proteins may be associated to those increases, and hence further studies are needed.Index terms: yellow "ipê", protein, Tabebuia alba. Envelhecimento acelerado de sementes de ipê em condições controladas de armazenamentoRESUMO -Objetivou-se estudar o efeito do armazenamento e do envelhecimento acelerado na germinação e no perfil das proteínas de reserva de sementes de Handroanthus albus. As sementes foram armazenadas em câmara fria e ao 0, 3, 6, 9 e 12 meses submeteu-se ao envelhecimento acelerado por 0, 24, 48, 72 e 96 h, e avaliou-se a germinação e o perfil proteico. O teste de germinação foi realizado sob luz constante a 25 °C. Para a extração das proteínas, utilizaram-se 125 mg de sementes maceradas com 2 mL do tampão de extração (1M tris HCl pH 8,8) e aplicadas em gel SDS-PAGE (3% e 15%) a 80 V .15 h -1 . O armazenamento por 12 meses associado a 72 h de envelhecimento acelerado aumentaram a germinação em aproximadamente 65% em relação às sementes não envelhecidas e envelhecidas por 24 h. Associado a este efeito benéfico, observouse a degradação e síntese de diferentes proteínas. Conclui-se que a germinação de sementes de Handroanthus albus não envelhecidas artificialmente é favorecida pelo armazenamento em câmara fria por três ou seis meses, e por nove ou 12 meses, associado ao envelhecimento acelerado. As proteínas de reserva podem estar associadas a este acréscimo e necessitam ser mais bem estudadas.Termos para indexação: ipê-amarelo, proteínas, Tabebuia alba.

Assessment of physiological, ultrastructural and biochemical alterations in naturally and artificially aged Handroanthus impetiginosus seeds

“…Handroanthus impetiginosus seed germination presented fluctuations during storage and artificial aging, as observed by Carvalho et al (1976), Kano et al (1978), Maeda and Matthes (1984), , Figliolia et al (1988), Cunha et al (1992), Kageyama et al (1992), Mello and Eira (1995), Gemaque (1999) and Shibata et al (2012). Increases in H. impetiginosus seed germination during storage were detected by Carvalho et al (1976) at 63 days of storage, Kano et al (1978) at 300 days, at 240 days and Mello and Eira (1995) at 540 days.…”

“…From the results obtained in this study it can be assumed that other factors, like heat shock proteins, regulate H. impetiginosus seed germination during storage and artificial aging, and more consistent studies are needed in different phases of seed development and germination of this species. In a study conducted by Shibata et al (2012) was concluded that germination of H. albus seeds, when not subjected to accelerated aging, is favored by storage in cold chamber during three to six months, or from nine to 12 months when subjected to accelerated aging process, and storage proteins may be associated to those increases.…”

Biochemical changes in Araucaria angustifolia (Araucariaceae) zygotic embryos during the storage

“…Other authors reported that the degradation of proteins in stored seeds of red clover (Trifolium incarnatum) and perennial ryegrass (Lolium perenne) was dependent on the severity of the storage conditions (Ching & Schoolcraft, 1968). The decrease in the intensity of bands was also observed in seeds of tree species yellow ipe (Handroanthus albus) after storage for 12 months in cold chamber, followed by artificial aging (Shibata, Coelho, Oliveira, & Garcia, 2012).…”

Biochemical and physiological changes of Tabebuia roseoalba (Ridl.) Sandwith (Bignoniaceae) seeds under storage

“…Ghasemnezhad and Honermeier (2007) also observed protein degradation during storage of sunflower seeds, which suggests that protein intake occurred with the release of amino acids for consumption on metabolic activity and respiration of the seeds. Changes in protein content were also associated with germination during storage of Handroanthus albus seeds, although further studies are still needed; thus, it can be inferred that reserve proteins may be associated with seed viability (Shibata et al, 2012).…”