Fluoride stress affects seed germination and seedling growth by altering the morpho-physiology of an African local bean variety

Abstract

Increased fluorine pollution represents a serious limitation for the productivity of important crops such as beans. The present study was conducted to detect antagonistic/synergistic ion mobility during seed germination in the presence of F contamination (KF and NaF). NaCl was used as a benchmark. The results showed that germination of Jesca, an African (Tanzania) bean variety, significantly dropped with high F levels (10% KF and 3% NaF). High F levels reduced Jesca growth and decreased root and shoot biomass (by 50% and 95% with KF and NaF, respectively). NaF 200 mg kg−1 had the most depressive effect on the seedling stage. Elevated F levels negatively affected seedling health, revealing toxicity symptoms such as chlorophyll degradation and low photosynthetic activities that degraded after a threshold level of 80 mg kg−1. In addition, an inhibitory effect of F on the mineral status of the seedlings, especially on the Ca content, was observed. An opposite trend of endogenous Ca response to NaCl stress was observed. Indeed, while endogenous Ca content increased with increasing NaCl concentration, it decreased when the F level increased. Therefore, tolerance to F at the germination and seedling stages might be used as a criterion for selecting F-tolerant bean varieties.

Tomato seed bio-priming with Pseudomonas aeruginosa strain PAR: a study on plant growth parameters under sodium fluoride stress

“…This shows that inoculating with P. aeruginosa strain PAR helps to lessen the negative impacts of NaF on seed germination, presumably through mechanisms like increased nutrition availability or stress tolerance induction. Chahine et al (2023) reported that Jesca (African-Tanzania bean variety) seed germination considerably declined with higher levels of fluorides (3% NaF and 10% KF). Pelc et al (2020) found that an upsurge in the fluoride concentration decreased seed germination, both in the roots and embryos of all tested cultivars of winter wheat.…”

“…This finding is critical to comprehend the practical implications of adopting P. aeruginosa strain PAR as a bioinoculant in fluoride-contaminated areas for sustainable agriculture. According to Chahine et al (2023) , high fluoride concentration reduced the growth and root-shoot biomass (95% and 50% with NaF and KF, respectively) of Jesca. Zulfiqar et al (2023) reported that fluoride toxicity was reduced using fluoride-resistant bacterial strains (SS-10a and SS-5a) in the soil.…”