Increasing crop productivity is our major challenge if we are to meet global needs for food, feed and fuel. Controlling the level of the plant hormones cytokinins is a mean of improving plant productivity. Cytokinin oxidase/dehydrogenase (CKO/CKX) is a major target in this regard because it degrades cytokinins. Here, we describe the synthesis and biological activities of new CKX inhibitors derived mainly from diphenylurea. They were tested on four CKX isoforms from maize and Arabidopsis, where the best compounds showed IC₅₀ values in the 10 ^-8 M concentration range. The binding mode of the most efficient inhibitors was characterized from high-resolution crystal complexed structures. Although these compounds do not possess intrinsic cytokinin activity, we have demonstrated their tremendous potential for use in the plant tissue culture industry as well as in agriculture. We have identified a key substance, compound 19, which increases stress resistance and seed yield in Arabidopsis, but also improves the yield of wheat, barley and rapeseed grains under field conditions. Thus our findings reveal that subtle modulation of cytokinin levels via CKX inhibition can positively affect plant growth, development and yield, and underline the fact that CKX inhibitors truly deserve to attract interest in plant biotechnology and agriculture

Three cytokinin derivatives (CKd) designated as RR-G, RR-O, and RR-V applied by foliar spraying at tillering, and one compound previously described as a cytokinin antagonist (CKa) designated as RR-P applied as a seed coating were tested in winter wheat and spring barley in field trial experiments. The aim of the study was to examine the influence of the compounds that were tested on the number of productive tillers, grain yield, and endogenous CK content. With the exception of the compound RR-V, the measured parameters clearly showed the stimulatory effects of CKd on tillering and grain yield in spring barley and winter wheat. The RR-V showed a stimulatory effect on the number of productive tillers and yield in spring barley, but not in winter wheat. Although in winter wheat CKa stimulated both the number of productive tillers and the grain yield, there was an inhibitory effect in terms of the number of productive tillers observed in spring barley. The results of the endogenous cytokinin analysis suggested, among others, the importance of the role of isopentenyl-adenine types of cytokinins in the tillering of spring barley. In conclusion, the cytokinin derivative compounds with an agonistic or antagonistic role showed strong potential for application in the future development of plant growth regulators.

The estimation of plant growth is a challenging but key issue that may help us to understand crop vs. environment interactions. To perform precise and high-throughput analysis of plant growth in field conditions, remote sensing using LiDAR and unmanned aerial vehicles (UAV) has been developed, in addition to other approaches. Although there are software tools for the processing of LiDAR data in general, there are no specialized tools for the automatic extraction of experimental field blocks with crops that represent specific “points of interest”. Our tool aims to detect precisely individual field plots, small experimental plots (in our case 10 m${}^2$) which in agricultural research represent the treatment of a single plant or one genotype in a breeding trial. Cutting out points belonging to the specific field plots allows the user to measure automatically their growth characteristics, such as plant height or plot biomass. For this purpose, new method of edge detection was combined with Fourier transformation to find individual field plots. In our case study with winter wheat, two UAV flight levels (20 and 40 m above ground) and two canopy surface modelling methods (raw points and B-spline) were tested. At a flight level of 20 m, our algorithm reached a $0.78$ to $0.79$ correlation with LiDAR measurement with manual validation (RMSE = $0.19$) for both methods. The algorithm, in the Python 3 programming language, is designed as open-source and is freely available publicly, including the latest updates.

European sugar production is influenced by the demand for alternative sweeteners, new technologies, and Common Agricultural Policy. Sugar beet is a biological resource with high carbon accumulation; chemically and energy-intensive crop with high rate of assimilation and carbon-dependent microbiome. The structure of associated greenhouse gas emissions is well known. In this review, currently available tools able to reduce environmental burden and the risk of resistance are summarized from the viewpoint of sustainability. In the field of herbicide protection, strip tillage combined with early-sown, fast-growing and freezing out intercrops is discussed, combined with tolerance to acetolactate synthase enzyme inhibitors, herbicide point application techniques, and autonomous inter-row weeding systems. Modern methods of insecticidal protection are based on cultivation of companion crops with camouflage or repellent effects, biological traps used by organic sugar beet growers and plant protection products based on essential oils. Current state of European insecticide scene calls for the utmost need for the integration of signaling methods and techniques of chemical and physical fixation of conventional plant protection products not burdened by resistance. Protection against pathogens is discussed according to the activity of the associated microflora, subsequently categorized into four lines of defense. Biofungicides are widely available, but for now, too technology-demanding and costly. The implementation of new fungicidal biotechnologies based on breeding associated with microbiome is very close, but – for now – still missing proper impulse for their introduction into practice, caused by a fundamental legislative restriction or economic pressure.

Phytic acid is the main storage of phosphate in grains of staple crops. As phytic acid is hardly digestible for non-ruminants microbial phytases are used to supplement animal feed to enhance phosphate digestibility. A fungal phytase gene was introduced into barley with the aim of enhancing phosphate digestibility. Transgenic homozygous barley over-expressing fungal phytase phyA showed a 3.3fold increase in mature grain phytase activity. Field trials at two locations in the Czech Republic were conducted in a five-year experiment to test transgene stability and activity under field conditions. Increased phytase activity gradually decreased over the generations showing the most significant drop in the initial years of field trials. Molecular analysis revealed methylation in the coding sequence of the phyA transgene, suggesting transcription gene silencing. On the other hand, herbicide resistance used for selection of transgenic plants was functional over all generations. The feasibility of crossing the transgene into the feeding cultivar Azit was demonstrated with subsequent stabilization of hybrid progeny through androgenesis. Our results indicate that the Azit genetic background tended to reduce phytase activity in mature grains of hybrids. Grain-specific over-expression of fungal phytase driven by an amylase promoter improved phosphate levels during germination. Unfortunately, a malting experiment revealed that phytase over-expression did not significantly improve malting parameters. In fact, the higher nitrogen content in unmalted grain negatively affected the quality of the malt produced from them.

Seedlings are highly vulnerable to various stresses due to their underdeveloped root and shoot systems. Climatic changes and abiotic stresses further hinder seedling emergence, while the excessive use of inorganic inputs harms soil health. Organically derived biostimulants, such as smoke-water, vermicompost leachate, and seaweed extract, offer promising alternatives. While their individual effects are well-documented, little is known about their combined role in seedling development. This study evaluated the synergistic effects of smoke-water (1:2000 v/v), vermicompost leachate (1:20 v/v), and Kelpak (0.5%) on the growth and vigour of essential agricultural (barley, rape, wheat) and vegetable (cabbage, carrot, cucumber, onion, pea) crops under growth chamber conditions. The combination significantly enhanced seedling growth, vigour indices, and α-amylase activity in wheat, cucumber, and pea under both dark and light conditions. Other crops demonstrated these benefits either under dark or light conditions, with variable α-amylase activity. The seedling vigour index, a key indicator combining seedling length and germination percentage, showed notable improvements across all crops. These findings highlight the potential of biostimulant combinations in promoting seedling emergence and call for further investigation into their physiological and biochemical mechanisms.