Electrical signals constitute an intricate aspect of plant physiology, transducing information and modulating various physiological functions. This study reveals amino acid glutamate and synthetic compound NMDA as exogenous cues, modulating electrical signals on single cell level in aquatic macro-algae Nitellopsis. The effect of NMDA in plant kingdom has been debatable, and the results of this study elucidate NMDA together with glutamate as active compounds and underline dose-dependent responses reflected in cell electrical signalling properties.

Plants must alter their photosynthetic ability in response to multiple external factors including light and nutrient availability. We have characterised the acclimation of plants that lack a copper transporter, which is required for efficient photosynthesis, and found that the regulation of expression of the photosynthetic machinery and general metal ion homeostasis is not perturbed in the mutant relative to a wild type. These findings have implications for our capacity to detect nutritional deficiency in plants.

Light intensity is a major environmental factor affecting the growth and survival of trees in a forest. The effect of light reduction on photosynthesis and photorespiration of Phoebe bournei, an evergreen broad-leaved tree, was examined with different growth irradiance. We found that the increase of photosynthesis in P. bournei leaves grown under shade treatments is associated with enhanced CO₂ diffusion and biochemistry, and we propose that enhancement of the photorespiratory is essential for shade leaves to improve photosynthesis.

In the ‘Auxin Transport’, space experiment, polar auxin transport in shoots of etiolated Golden Cross Bantam maize grown in space was greater than those grown on Earth. Microgravity substantially altered ZmPIN1a localization in plasma membranes of the parenchymatous cells of the coleoptiles, shifting mainly towards the vascular bundle direction. These findings contribute to the field of gravitational physiology in plants, and also to development of plant cultivation system in space for long-term exploration of space by human being in future.

Nitrogen availability has a major impact on tea productivity; however, how tea plants respond to different N forms remain unknown. Our findings reveal the molecular mechanisms of redox homeostasis and signalling in alleviating oxidative stress induced by N deficiency or NO₃^–. This paper provides candidate redox-related genes for researchers investigating abiotic stress in tea plants.

Stevia is a herbaceous plant containing low-calorie sweeteners that could be regarded as a successor to sugar for diabetics. Leaf growth of this plant is restricted in the greenhouse whereas the increase in leaf (as the main source of sweeteners) and sweeteners are economically beneficial for farmers and stevia extract factory. The results showed that substances used in this research increased the sweeteners and leaves yield, which is a very promising strategy to increase the plant cultivation yield.

Whether tissue size or cell numbers determine fruit growth and sink strength is not known, because cell number and tissue size are strongly correlated. Using a diploid cultivar and its tetraploid (with larger ovaries made up of larger cells but in similar number) as a biological model, we separated these effects and found that fruit growth and sink strength correlated with cell number across genotypes but not to tissue size. This is fundamental knowledge for fruit growth modelling and management.

Potatoes, which are the staple food in most countries and the fourth largest food crop worldwide, are native to subtropical regions and are particularly sensitive to cold stress. Our results showed that endogenous glycine betaine can protect plant photosynthetic systems, improve the antioxidant capacity and cold resistance of potatoes. This study enriches existing methods to improve potato cold resistance.

Wheat nocturnal transpiration is thought to lead to ‘wasteful’ water losses, but its pre-dawn increase is hypothesised to be beneficial. We applied simulation modelling to quantify yield gains or penalties arising from these theorised strategies in the Mediterranean environment of Tunisia. Increased yield performance under drought was associated with genotypes reducing overall night-time water loss, but maximising its circadian increase at the end of the night, which enabled enhancing radiation use efficiency on the following day.

Although light is essential to photosynthesis, few studies have examined the effects of different LED spectra on photosynthate distribution in potato plants. Treatments under red light promoted ¹³C assimilation and had more large tubers than other treatments, whereas plants under blue light distributed more photosynthates into tubers rather than other organs and showed balanced tuber development. This information could provide a new way to regulate the production of seed potatoes in plant factories.