Entries by Carlos A. Ordóñez-Parra

How does fire affect germination of grasses in the Cerrado? ($) (Seed Sci. Research)

Fire shapes tropical savannas through direct (i.e., heat and smoke) and indirect (i.e., opening gaps) effects on the vegetation. However, its effects on seeds from neotropical grasses have seldom been addressed. In this paper, Dariel and Fidelis assessed the longevity and the impact of fluctuating temperatures –a consequence of gap-opening– and heat shocks on the […]

Melatonin represses oil and anthocyanin accumulation in seeds (Plant Physiol.)

Seed oils and anthocyanins play several roles in plant physiology and are promising substances for crop engineering given their benefits for human health. Recent studies proposed that melatonin –a potent antioxidant present in all plant species– regulates the deposition of these metabolites in seeds, but the mechanism behind this is still missing. In this paper, […]

The negative effect of a vertically transmitted fungal endophyte on seed longevity is stronger than that of ozone transgenerational effect ($) (Environ. Exp. Bot.)

Global environmental change brings new challenges to plants at different levels, including seed development and persistence. For example, the increasing ground-levels of ozone (O3) can affect seed viability, as a result of changes in the mother plant antioxidant machinery. These responses might depend on the ontogenic state of the plants and the interaction with symbiont […]

Intertwined signatures of desiccation and drought tolerance in grasses (PNAS)

Desiccation tolerance (i.e., the capacity of surviving with very low water content) is widespread in seeds and pollen, but quite rare in vegetative organs. Most authors agree that in angiosperms it originated multiple independent times from rewiring seed desiccation tolerance pathways. Here, Pardo et al. sequenced the genome of Eragrostis nindensis, a species from a […]

How animals shaped fruit traits, and how they did not (Funct. Ecol.)

The dispersal syndrome hypothesis states that frugivores and fleshy-fruited plants coevolve by exerting selective pressures on each other. Even though this idea still prevails, some theoretical issues could make this scenario improbable. As a result, a new chicken-or-egg dilemma appeared: are the frugivores responsible for fruit evolution, or is it the opposite? In this fascinating […]

Nikolaeva et al.’s reference book on seed dormancy and germination ($) (Ecology)

In 1985, Marianna Nikolaeva, Marina Razumova, and Valentina Gladkova published the Reference Book on Dormant Seed Germination. There they provided details on the germination ecology of different plant species –mostly from Northern Europe and Russia. However, since the original publication was in Russian, it remained unnoticed for most seed scientists outside Russia. Fortunately, Rosbakh et […]

Review: Delayed luminescence of seeds: are shining seeds viable? (Seed Sci. Technol.)

Most of the current methods for assessing seed viability are time-consuming and destructive. As an alternative, some authors have suggested using procedures based on delayed luminescence; an ultra-weak light emitted by biological materials exposed to illumination. Here, Adeboye and Börner review the history of seed viability testing, the milestones in the study of delayed luminescence, […]

DNA methylation and integrity in aged seeds and regenerated plants ($) (Seed Sci. Res.)

Understanding seed aging is crucial to comprehend seed longevity in the field and to design ex situ conservation programs. However, the mechanisms behind seed aging are underexplored. In this paper, Mira et al. assessed the changes in DNA integrity and methylation between aged and non-aged seeds of Mentha aquatica and the seedlings obtained from these […]

Ploidy affects the seed, dormancy and seedling characteristics of a perennial grass, conferring an advantage in stressful climates ($) (Plant Biol.)

Both polyploidy (i.e., having more than two sets of chromosomes) and seed traits influence plant fitness. However, the interaction between these two factors is underexplored. Here, Stevens et al. tested the effect of polyploidy and seed developmental environment on 1) seed viability and mass; 2) seed dormancy; 3) seed germination under drought; and 4) seedling […]