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-Long-term survival during dry storage or longevity is a pre-requisite to avoid deterioration, leading to loss of vigor. Longevity is routinely evaluated by the ability to germinate after storage. It increases progressively during seed maturation, after the acquisition of desiccation tolerance. However, the capacity to germinate represents only a part of the success of crop establishment. How seed maturation affects the resistance of several traits, as vigor, associated with seedling establishment, against deterioration was evaluated during seed filling and post-abscission phase of soybean BRS 284 seeds. Three new phenological stages between 7.1 and 7.2 (7.1.1, 7.1.2 and 7.1.3) were introduced to capture the rapid increase in seed longevity. Germination speed started to be affected at 7-14 days after storage depending on the stages. The delay on germination increased with maturation from 7.1.3 to dry mature seeds. The time to 50% loss of elongation capacity of both organs during storage was similar to that of loss of germination. Also, it increased steadily during seed maturation after mass maturity and harvest maturity stages, highlighting the importance of the late phase of seed maturation for building seed vigor.Index terms: Glycine max, elongation, hypocotyl, longevity, maturation.Maturação tardia da semente preserva a emergência de plântulas de soja submetidas ao armazenamento RESUMO -A sobrevivência durante o armazenamento ou longevidade é pré-requisito para evitar a deterioração, que leva à perda de vigor. A longevidade é rotineiramente avaliada pela habilidade da semente em germinar depois do armazenamento, que aumenta progressivamente durante a maturação depois da aquisição da tolerância à dessecação. No entanto, a germinação representa somente uma parte do processo de estabelecimento da planta. Foi avaliado como a maturação afeta a resistência de várias características, como vigor, relacionadas ao estabelecimento das plântulas em sementes de soja da variedade BRS 284. Três novos estádios entre 7.1 e 7.2 (7.1.1, 7.1.2 e 7.1.3) foram introduzidos para capturar o rápido aumento na longevidade das sementes. O armazenamento induziu uma queda na velocidade de germinação a partir de 7-14 dias de armazenamento, dependendo do estádio, e essa queda diminuiu com a maturação, a partir do estádio 7.1.3. O tempo para perda de 50% na capacidade de alongamento de ambos os órgãos foi similar àquele observado para capacidade de germinação. Além disso, esse tempo aumentou de forma constante durante o período de maturação, demonstrando a importância das fases finais de maturação da semente na construção do vigor.Termos para indexação: Glycine max, alongamento, hipocótilo, longevidade, maturação.1

Bioenergy is one of the alternatives to reduce the dependence of global energy on fossil fuels. The short rotation coppice (SRC) of eucalypt species appears as an interesting option for forest biomass production in a short time. However, the harvesting of whole trees (included the crown) in SRC systems has implications on sustainable land use. More information is required on the increase of biomass as renewable energy resource to achieve the sustainability of these crops. The main objective of this research was to evaluate the sustainable use of biomass from very high-density eucalypt plantations, managed at tropical conditions for bioenergy. To accomplish this objective, the tree was fractionated into three fractions: stem, branches, and leaves, and there was determination of the dry matter, energy yield, and nutrients export. This experiment used a short rotation coppice, a hybrid clone of Eucalyptus urophylla  Eucalyptus grandis, of 2 years old. According to the results obtained, the density planting and fertilization levels have a greater influence on the dry matter yield, energy yield, and nutrient exports. The higher density planting reaches mean values of 30.9 tonnes of dry matter per hectare (t DM ha À1) and 743.3 GJ ha À1. Considering the biomass yield and nutrients export of short rotation coppice of eucalypt, the higher density planting with the lower dose of fertilization is more indicative of sustainable use. The leaves have an important participation in nutrients export and should be retained in the soil of forest.

Objective. To determine if acid-etched, cross-linked dentin can be dehydrated without lowering bond strength below that of cross-linked wet-bonded dentin in vitro.Methods. Using extracted human third molars, control acid-etched dentin was bonded with Single Bond Plus, using either the wet-or dry-bonding technique. Experimental acid-etched dentin was treated with 5 mass% grape seed extract (GSE) in different solvents for 1 min before undergoing wet vs dry resin-dentin bonding with Single Bond Plus. Completely demineralized dentin beams were treated with 5% GSE for 0, 1 or 10 min, before measuring stiffness by 3-point flexure. Other completely demineralized beams were treated similarly and then incubated in buffer for 1 week to measure the collagen solubilization by endogenous dentin proteases.Results. 24 h microtensile bond strengths (TBS) in wet and dry controls were 53.5 ± 3.6 and 9.4 ± 1.8 MPa, respectively (p < 0.05). 5% GSE in water gave TBS of 53.7 ± 3.4 and 39.1 ± 9.7 MPa (p < 0.05), respectively, while 5% GSE in ethanol gave TBS of 51.2 ± 2.3 and 35.3 ± 2.0 MPa (p < 0.05). 5% GSE in 5% EtOH/95% water gave wet and dry TBS of 53.0 ± 2.3 and 55.7 ± 5.1 MPa (p > 0.05). Cross-linking demineralized dentin with 5% GSE increased stiffness of dentin and decreased collagen degradation (p < 0.05).