Potential innovation in Plant research through the use of gene-edited and genetically modified plants iscurrently being hindered by inefficient and costly plant transformation. We show that naturally occurring carbon dots (quasi-spherical, <10nm nanoparticles) can act as a fast vehicle for carrying plasmids into mature plant cells, resulting in transient plant transformation in a number of important crop species with no negative impacts on photosynthesis or growth. We further show that GFP, Cas9, and gRNA introduced into wheat via foliar application (spraying on) of plasmid coated carbon dots are expressed and, in the case of Cas9, make genome edits in SPO11 genes. Therefore, we present a protocol for spray-on gene editing that is simple, inexpensive, fast, transforms in planta, and is applicable to multiple crop species. We believe this technique creates many opportunities for the future of plant transformation in research and shows great promise for plant protein production systems.Recent advances in plant biotech, particularly manipulation of photosynthesis, have shown the ability to obtain huge increases in plant efficiency and yield. For example, the RIPE project 1 obtained up to a 15% increase in biomass 2 and a ∼40% increase in productivity 3 by reducing photoprotection latency times and by avoiding photorespiration. These examples show the true power of GM -not only could these changes increase global food security (a growing issue with our population still increasing 4,5 , and climate change conferring multiple environmental stresses 6-8 ), but since these advances also increase the amount of carbon being fixed, it could have potential for also mitigating climate change 9,10 . This is important because, as noted, the effects of climate change exacerbate food insecurity further.Plant biotechnology can also enhance food security and biomass production by improving crop resistance to herbivores, pests, and environmental stresses. Additionally, GM techniques can enhance the nutritional value of the food produced, as seen with purple tomatoes 11,12 , enhancing the lipid content of oil crops to provide an alternative to dwindling fish oil stocks 13,14 and improving the quality of staple crops such as wheat 15,16 .However, the scope extends beyond edible compounds, as plant biotech is allowing the production of biofuels 17 , and has shown success producing pharmaceuticals 18 , including the efficient and speedy production of vaccines 19 . These advancements have been aided by new fields such as Synthetic biology, and gene editing tools becoming more versatile and useable.However, there is currently a significant bottleneck 20 limiting the potential application of these ideas and advances, and that is the cost, both in time and resources, of current plant transformation methods. All plant transformation must currently utilise either Agrobacterium tumefaciens 21 , biolistics 22 , or regeneration from PEG transformed protoplasts 23 , as a vehicle to introduce DNA, regardless of whether the changes are transient (n...

Despite controlling a diverse array of regulatory processes in plants, UV-B wavelengths (280-315 nm)are attenuated by common greenhouse materials such as glass and polycarbonate and are therefore depleted in many commercial growing environments. In this study, we analysed the architecture, pigment accumulation and antioxidant capacity of coriander (Coriandrum sativum, also known as cilantro) plants grown with and without supplementary UV-B (1.5 µmol m −2 s −1 ). We demonstrate that UV-B limits stem elongation responses to neighbour proximity perception (shade avoidance), promoting a more compact plant architecture. In addition, UV-B increased leaf quercetin content and total antioxidant capacity. Arabidopsis thaliana mutants deficient in flavonoid biosynthesis were not impaired in shade avoidance inhibition, suggesting that UV-B-induced flavonoid synthesis is not a component of this response. Our results indicate that UV-B supplementation may provide a method to manipulate the architecture, flavour and nutritional content of potted herbs whilst reducing the deleterious impacts of dense planting on product quality.UV-B comprises less than 1% of sunlight, yet regulates a wide range of physiological and developmental processes in plants. These include the production of protective sunscreen compounds, plant growth, photosynthesis, stomatal regulation and defence against pests and pathogens 1 . In Arabidopsis, photomorphogenic UV-B signals are perceived by the photoreceptor UV RESISTANCE LOCUS 8 (UVR8) 2 . Upon UV-B absorption, UVR8 dimers monomerise and interact with the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) to initiate the transcriptional regulation of hundreds of genes 3 . The most striking phenotype displayed by UV-B-treated plants is a reduction in plant size, resulting from reduced leaf expansion and an inhibition of stem elongation 4,5 . This is most apparent in environmental conditions whereby stem elongation is promoted, such as exposure to low red to far red ratio light (low R:FR) 5 , and high temperature 6 . Low R:FR is a component of vegetational shade and a signal of neighbour proximity prior to shading 7 . Plant perception of reduced R:FR by phytochrome photoreceptors leads to a rapid elongation of stems, as plants attempt to overtop neighbours. This response is largely driven by an increase in auxin synthesis, via low R:FR-mediated stabilisation and activation of PHYTOCHROME INTERACTING FACTOR (PIF) transcription factors 7 . UV-B perceived by UVR8 decreases auxin activity by reducing PIF4/5 abundance and activity. This is achieved by promoting PIF degradation 5 , increasing levels of ELONGATED HYPOCOTYL 5 (HY5) transcription factor (which competes with PIF4 for target promoters) 8 and increasing levels of growth-suppressing DELLA proteins which bind to PIFs, inhibiting their function and promoting their degradation 5,9,10 .Control of stem length is a key objective in horticulture, where the aesthetic quality of plants is paramount to commercial success. Excessive stem growth can ...