Planting speed has an important impact on plant spacing variability and also grain yield. In a two-year study, the effects of planting speeds of 6, 9, and 12 km/h on maize plant spacing and, consequently, ear parameters were investigated. We wanted to determine whether increasing the planting speed increases the plant spacing parameters and what effects this has on ear parameters and grain yield. In both experimental years, no differences between the three planting speeds were found in terms of mean plant spacing, plant density, the multiple index, and the miss index. However, the standard deviation of reference spacings and precision increased with the increase in planting speed from 6 to 12 km/h. In 2022, the differences between plant spacings measured using UAV photogrammetry and manual measurements were smaller (<1 cm) than in 2023. The plant spacing data obtained from 3D point clouds show a strong correlation (r = 0.97) with the manual measurements for all three planting speeds. The proposed method is suitable for measuring plant spacing in maize. In 2022, no differences appeared in grain yield and ear parameters between the planting speeds; however, in 2023, the grain yield and kernel mass per ear were greater at planting speeds of 6 and 9 km/h than at a planting speed of 12 km/h in 2023. Individual ear analysis in 2023 showed an increase of 0.73 g in kernel mass per plant with a 1 cm increase in plant spacing, resulting in a 58 kg/ha yield increase.

In 2002, 2003, and 2004, a field trial was carried out in three locations in Slovenia, i.e., Pšata, Brnik, and Brežice with two different inter-row widths (IRWs) of 75 cm and 90 cm using three different potato cultivars (i.e., Agria, Bright, and Carlingford). The aim of this trial was to determine the influence of inter-row width (75 cm or 90 cm) with three potato cultivars on the market yield, the yield of green tubers, the cross-sectional area of the ridge, and the percentage of tubers with a hollow heart or blackspot. The trial was designed in the form of split plots with five repetitions. In the years with abundant rainfall during the period of growth (2002 and 2004), when plants completely covered the ground, the market yield at the 90 cm IRW was higher than at the 75 cm IRW. In 2003, however, the market yield was higher at the 75 cm IRW. The yield of green tubers was lower at the 90 cm IRW than at the 75 cm IRW, due to a larger cross-sectional area of the ridge (> 1000 cm2). Thus, the soil covering of tubers in the ridge was better. The hollow heart and blackspot disorders affecting the tubers depend more on the susceptibility of a particular cultivar and the meteorological conditions during the period of growth than the IRW. The findings showed that the Agria cultivar was more susceptible to the hollow heart disorder, particularly in the years with a higher yield with thicker tubers (2002 and 2004). The Bright cultivar was affected by blackspot in 2003, the year with a lack of rainfall.

Spraying parameters are important factors when spraying wheat heads against fusarium head blight (FHB) to control the deoxynivalenol level in the grain and to obtain high and quality yields. In 2019 and 2020, field trials were conducted in order to establish the effect of the spraying pressure (2 bar, 4 bar, and 6 bar) of special nozzles with a variable flow rate Agrotop VR 1.5 on the head fungicide coverage, yield parameters, and the deoxynivalenol (DON) value in the grain. The coverage of the front and rear sides of wheat heads increased with the increase of spraying pressure from 2 to 6 bar. In 2019, when the infection with FHB was more severe, no significant differences appeared in the yield and the hectoliter weight at a lower spraying pressure, while the DON value at this pressure approached the maximum permissible level. In that year, the DON value exponentially fell with the increase of spraying pressure. In 2019, the thousand grain weight was higher at the spraying pressure of 6 bar than at the pressures of 2 and 4 bar. The results show that also a lower spraying pressure (2 bar) and a volume application rate (117 L/ha) below the recommended one suffice to retain the DON value in the grain below the maximum permissible level, even in years with more severe infection.

Slaughterhouse waste (SW) is potentially a good source of biomethane; however, its excessive ammonia content quickly causes inhibition of microbial processes. Our aim was therefore to remove ammonia from SW before putting it into a biogas reactor. Experimental 120 L pressure container was constructed to observe NH₃ removal from diluted slaughterhouse waste at constant air flow of 144 NL/min, temperature 130 °C, and at different pressures: 300 kPa, 600 kPa, and 900 kPa. SW was first allowed to hydrolyze for 14 days at 38 °C. The SW was diluted with water (DSW) to 8.4% dry matter (DM) and forcibly aerated for 334 min. From the DSW, 0.7%, 3.8%, and 9% of initial total N were removed at 300 kPa, 600 kPa, and 900 kPa, respectively. However, the C/N ratio changed only slightly, from the initial 4.38 to 3.17, which is not a promising result for biomethanization. Further research on the presented system with the addition of bases might be promising to remove more ammonia.

Technical testing of the equipment for the application of plant protection products (PPP) was performed in Southeastern Slovenia in the period from 2004 to 2013. The technical conditions of boom or orchard sprayers was examined in details and the following parts were checked: drive, anti-drip valves, nozzles, filters, pipes and tubes, manometers, all valves, pressure regulators, agitator, pump, liquid discharge, spray solution reservoir and spray boom or fan system. The analysis revealed a poor condition of most devices in the initial years. However, technical suitability improved drastically until 2013. Technical condition was not directly related to the region of inspection although the lowest number of defective sprayers was recorded in the Posavje region. This can be linked to higher frequency of use and maintenance of the sprayers in this region as it stands out as the area with larger farms. Occasional technical disorders of the equipment can be recorded each year. It is therefore essential to continue with regular technical inspection to ensure optimal and accurate functioning of the sprayers.

This study explores the feasibility of an automated sensor system for precise plant protection product application in plum orchards, aiming to address issues related to inefficient spraying practices, environmental pollution, and reduced crop quality associated with traditional training systems. The research focuses on detecting tree canopy presence, evaluating electromagnetic valve actuation in different plum training systems, and optimizing plant protection product usage. Sensor-based spraying demonstrates its potential to improve operational efficiency, reduce product losses, and foster environmentally responsible agricultural practices, contributing to the broader field of precision agriculture. For the selected scene, the results show the possibility of a substantial savings of 71.37%, 47.17%, 58.59%, and 55.06% for the One-axis, Bi-axis, UFO, and Combine systems, respectively. Implementing this technology can potentially lead to significant improvements in plum orchard operations while minimizing the industry’s ecological impact on the environment.