Sowing or seedbed depth is an important agro-technological parameter that varies with specific on-field soil and microclimatic conditions and depends on crop biology. There is a lack of detailed information regarding how seedbed depth relates to other seedbed parameters and affects the development of agricultural crops. Several seeder constructions and methods for seeding condition detection and depth adjustment have been investigated in high-precision, digitally backgrounded, in-site sowing systems; however, there is still a gap in knowledge due to the limited use of these technologies in conditions of high soil and micro-climatic variability. Therefore, the aim of this study was to highlight the impact of sowing depth on crop seedbed parameters, mainly established by the Kritz method, to ascertain the correlation between sowing depth, germination, crop development and productivity, and to overview the methods and equipment used for detection, adjustment and control of sowing depth in precision site-specific sowing systems. Our results showed that, in most cases, when sowing depth extended beyond the optimum, the moisture content in the seedbed decreased significantly. Sowing depth also correlated with the roughness of the seedbed (surface and bottom) and seedbed aggregate size distribution, but the direction of the relation depended on crop type and maximum sowing depths. Sowing depth correlated with crop germination, development and productivity parameters; however, the direction of exposure and intensity also varied with respect to crops, weather conditions, tillage and sowing equipment. Sowing depth uniformity is greatly influenced by the regulation of clamping force, the spatial variability of soil in fields and sowing operation speed.

Crop biomass is valuable not only from a nutritional and fodder point of view, but also from an energetic point of view. The main task is to increase biomass production while maintaining low nutrient and pesticide requirements and low ecological footprint. A stationary three-year field experiment was performed at the Experimental Station of Vytautas Magnus University, Lithuania, in 2020–2022. Single crops and mixtures of maize, hemp, and faba bean were investigated in terms of their biomass productivity. Results showed that as the crop diversification increases, the productivity of maize and hemp grown in the mixture decreases, while faba bean ensures high dried biomass productivity. During the three years of the experimentation, the highest total dried biomass was found in the ternary crop: on average, 1495.4 g m−2 per year. The highest dried biomass of the ternary crop was established in the first year of experimentation: 2081.1 g m−2. A decrease in biomass yields in the second and third years of the experiment was observed in all treatment plots. The results suggest that the low fertilization level (totally N 45, P 45, K 45 kg ha−1) in the experiment should be increased if multi-crop cultivations are to be regrown during vegetative seasons.

The investigations were carried out at the Experimental Station of Vytautas Magnus University Agriculture Academy, in 2021. The soil of the experimental site is silty light loam Planosol. The aim of the study was to determine the impact of multi-cropping intensity on the prevalence and damage of diseases and pests, as well as on weed abundance and biomass. The methods of crop diversification were studied: 1. Maize mono-crop (KU);2. Hemp mono-crop (KA);3. Faba bean mono-crop (PU);4. Maize and hemp binary-crop (KU + KA);5. Maize and faba bean binary-crop (KU + PU);6. Hemp and faba bean binary-crop (KA + PU);7. Maize, hemp and faba bean ternary-crop (KU + KA + PU). Contrary to expectations, the number of pests found in the hemp mono-crop (KA) and faba bean mono-crop (PU) was lower and the damage caused was lower than in the binary and ternary crops. Crop diversification has been an effective method of controlling faba bean diseases. The lowest abundance and intensity of Botrytis fabae and Ascochyta fabae were found in hemp and faba bean binary-crop (KA + PU). Binary maize and faba bean crop (KU + PU) were most effective in weed controlling, with the lowest number and biomass of weeds.