Climate and seed size of a dry forest species: influence on seed production, physiological quality, and tolerance to abiotic stresses

Abstract

Seed production, quality and germination are likely to be affected by a drastic climate change in semi-arid areas predicted for the end of the century. We evaluated Anadenanthera colubrina var. cebil (Griseb.) Altschu (Fabaceae) seeds of different sizes, populations and harvest years for germination and tolerance to environmental stresses aiming to predict impacts of future climate. Seeds were accessed for germination temperature, salinity and osmotic limits and requirements. Germination of large and small seeds harvested in different populations was evaluated in optimum and stressful temperature, salinity and water deficit. A glasshouse pot assay tested weekly irrigation regimes and seedlings emergence and growth. Optimal temperature for seeds germination was 34.8 oC and limits were 5.6 oC and 50.9 oC. Large and small-sized seeds do not differ in germination, however small seeds are more efficient in stressful conditions. Seedlings can emerge and grow under small weekly irrigation for four months. The predicted increase in temperature will not impair germination, however, the time available for seedling establishment will decrease due to lacking rainfall. The increase in the amount of small-sized seeds produced in drought years is a strategy for coping with harsh environments, rather than a decrease in seed quality.

Physiological maturity of Cenostigma tocantinum Ducke (Fabaceae) seeds

“…Additionally, these fluctuations in dimensions may be related to climatic factors that affect the synchronization of the fruiting process among individuals during development (Mata et al, 2013) or may also reflect seed quality (Oliveira et al, 2020;Gomes et al, 2023). Due to this variability, for some species like Mimosa caesalpiniifolia Benth., fruit biometric parameters were not effective in assisting in maturity point determination (Alves et al, 2005).…”

Can Modification of Sowing Date and Genotype Selection Reduce the Impact of Climate Change on Sunflower Seed Production?

“…Additionally, the predictions indicate that agricultural droughts will double with a temperature increase of 1.5 • C [2]. Forecasts suggest that, by the end of the 21st century, semi-arid regions will likely experience significant negative effects of climate change, which will impact seed production, the quality of produced seeds [3], and the entire economy [4].…”