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Abiotic stresses significantly disrupt plant physiology at the molecular, biochemical, and morphological levels, often causing irreversible damage. To ensure sustainable coffee production, it is essential to understand how environmental stresses—such as drought, heat, excess light, and salinity—affect plant growth, and to develop strategies to mitigate their impact. Despite the limited number of studies on this topic, compiling existing knowledge can provide valuable insights into how coffee plants respond to such stresses. Specifically, understanding whether coffee plants can endure damage caused by these stresses and the mechanisms they employ to do so is critical. This review aims to (i) summarize key findings on the effects of drought, heat, excess light, and salinity on coffee plants and their coping mechanisms; and (ii) explore plant breeding and nutrition as potential strategies to mitigate these abiotic stresses and enhance coffee production. [ABSTRACT FROM AUTHOR]

Investigating the ability of non-hyperaccumulator plants to grow in soils polluted by cadmium (Cd) and their potential for phytostabilization or phytoextraction is essential for assessing their use in phytomanagement efficiency. Therefore, we evaluated the tolerance of high-biomass grasses to Cd by measuring biomass production and element accumulation and valued them for their suitability for phytoextraction or phytostabilization purposes on moderately Cd-polluted land (total Cd concentration of 7.5 mg kg−1) by determining Cd accumulation in the plants and calculating the bioconcentration (Cd BCF) and translocation factors (Cd TF). Among the ten species under investigation, Panicum maximum cv. Massai and Pennisetum glaucum cv. Purpureum Schum showed lower root biomass due to Cd exposure. Cadmium exposure altered element accumulation in some grass species by reducing P, K, and Mg accumulation in P. glaucum cv. Purpureum Schum; K accumulation in P. maximum cv. Massai; Mg accumulation in P. maximum cv. Mombaça; Ca, Fe, and Zn accumulation in P. maximum cv. Aruana; and B accumulation in Brachiaria brizantha cv. Piatã. However, this was not correlated with lowered biomass production, except for K, which was associated with lowered root biomass allocation in P. maximum cv. Massai and P. glaucum cv. Purpureum Schum. Cadmium concentrations decreased from roots to shoots, indicating a clear limitation of upward Cd transport. Although some grasses exhibited a Cd BCF > 1, the Cd TF remained below 0.4 for all tested species. These results indicate that, under moderate Cd pollution, the evaluated grasses are more suitable for Cd phytostabilization than phytoextraction, except for P. maximum cv. Massai and P. glaucum cv. Purpureum Schum, which showed inhibited root growth and may not be efficient over time. [ABSTRACT FROM AUTHOR]

Abstract Background The cultivar Micro-Tom (MT) is regarded as a model system for tomato genetics due to its short life cycle and miniature size. However, efforts to improve tomato genetic transformation have led to protocols dependent on the costly hormone zeatin, combined with an excessive number of steps. Results Here we report the development of a MT near-isogenic genotype harboring the allele Rg1 (MT-Rg1), which greatly improves tomato in vitro regeneration. Regeneration was further improved in MT by including a two-day incubation of cotyledonary explants onto medium containing 0.4 μM 1-naphthaleneacetic acid (NAA) before cytokinin treatment. Both strategies allowed the use of 5 μM 6-benzylaminopurine (BAP), a cytokinin 100 times less expensive than zeatin. The use of MT-Rg1 and NAA pre-incubation, followed by BAP regeneration, resulted in high transformation frequencies (near 40%), in a shorter protocol with fewer steps, spanning approximately 40 days from Agrobacterium infection to transgenic plant acclimatization. Conclusions The genetic resource and the protocol presented here represent invaluable tools for routine gene expression manipulation and high throughput functional genomics by insertional mutagenesis in tomato.

An increase in the content of heavy metals in the environment causes many socio-environmental problems, and phytoremediation is a tool to reduce the environmental impact caused by these elements, with prospects for the use of forage grasses. This group of plants features characteristics for the environmentdecontamination process, but further studies are necessary about the damages caused by heavy metals on the uptake of cationic micronutrients and on the antioxidant system, which are essential processes for the growth of plants in contaminated sites. Exposure of forage grasses to heavy metals results in a lower content of Mn in the shoots of almost all plants, but the contents of Cu, Fe, and Zn vary according to heavy metal and forage grass. Activities of enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and guaiacol peroxidase (GPX) usually increase to reduce the oxidative stress induced by heavy metals, but when the content of any of these metals is high, enzymatic activity is decreased. Scale of toxicity of heavy metals to forage grasses can be described as: Pb ≈ Cr > Cd ≈ As > Zn ≈ Cu ≈ Ni > Mn. [ABSTRACT FROM AUTHOR]