The impact of drought on wheat (Triticum aestivum L.) production is shown, using an example data set of almost 60 yr from six climate‐specific regions in Poland. Drought was measured using the standardized precipitation index (SPI) and the hydro‐thermal coefficient of Selyaninov (HTC). Yield trends were estimated by Bayesian linear regression over two periods, 1961–1991 and 1992–2019, identified by a changepoint detection method. Bayesian inference is used as it allows the estimation of a credible interval of regression coefficients instead of point estimates and asymptotic confidence intervals, thus comparisons between regression coefficients are more meaningful. We detected an increase in yield in both time periods and in all regions. The average winter wheat yield increased by 97% in the first period and by 35% in the second (19.8–39.1 dt ha⁻¹ and 32.9–44.5 dt ha⁻¹, respectively). Spring wheat yield increased by 96% in the first period and by 42% in the second (16.8–37.9 and 22.9–32.5 dt ha⁻¹, respectively). Yield losses in drought years were estimated using the paired t test to compare mean difference between real yields and yields estimated from regression lines for nondrought years. The highest yield losses due to drought were in regions I (–19.3% spring wheats, –6.3% winter ones) and III (–16.1% spring and –8.3% winter wheats) over the 1992–2019 period.

Cultivar recommendation based on mean performance determined by multi-environment trials (METs) conducted on research stations could be unreliable and ineffective for assessing performance in farmers’ fields. It is important to improve the efficiency of cultivar recommendation based on METs. For this purpose, it would be useful to validate recommendations based on yield data obtained directly from farmers, i.e., through surveys. The aim of this study was to discuss the possibility and statistical methodology of assessing cultivar performance patterns based on yield data obtained through farmer surveys. We suggest that this might be accomplished by assessing the conformity of yield ranking and yield performance patterns between MET and survey datasets in the same growing regions. As an example, we compare winter wheat (Triticum aestivum L.) yield data obtained from Polish farmers via surveys with data obtained via METs. In the METs, cultivars were evaluated at two levels of crop-management, a moderate-input management (MIM) system and a high-input management (HIM) system. Based on the yield evaluations in the current study, half of the agro-ecological regions had relatively high levels of consistency in yield rankings between the MET MIM system and survey yield dataset. This indicated a relatively high efficiency of cultivar recommendations based on METs in these regions, especially for the MIM system. For the HIM system, however, with the exception of one region, we observed a poor degree of consistency in cultivar ranking.

Among European countries, Poland has the largest gap in the grain yield of winter wheat, and thus the greatest potential to reduce this yield gap. This paper aims to recognize the main reasons for winter wheat yield variability and shed the light on possible reasons for this gap. We used long-term datasets (2008–2018) from individual commercial farms obtained by the Laboratory of Economics of Seed and Plant Breeding of Plant Breeding and Acclimatization Institute (IHAR)-National Research Institute (Poland) and the experimental fields with high, close to potential yield, in the Polish Post-Registration Variety Testing System in multi-environmental trials. We took into account environment, management and genetic variables. Environment was considered through soil class representing soil fertility. For the crop management, the rates of mineral fertilization, the use of pesticides and the type of pre-crop were considered. Genotype was represented by the independent variable year of cultivar registration or year of starting its cultivation in Poland. The analysis was performed using the CART (Classification and Regression Trees). The winter wheat yield variability was mostly dependent on the amount of nitrogen fertilization applied, soil quality, and type of pre-crop. Genetic variable was also important, which means that plant breeding has successfully increased genetic yield potential especially during the last several years. In general, changes to management practices are needed to lower the variability of winter wheat yield and possibly to close the yield gap in Poland.

Summary: Wheat is one of the modern world’s staple food sources. Its production requires good environmental conditions, which are not always available. However, agricultural practices may mitigate the effects of unfavorable weather or poor-quality soils. The influence of environmental and crop management variables on yield can be evaluated only based on representative long-term data collected on farms through well-prepared surveys.The authors of this work analyzed variation in winter wheat yield among 3868 fields in western and eastern Poland for 12 years, as dependent on both soil/weather and crop management factors, using the classification and regression tree (CART) method. The most important crop management deficiencies which may cause low wheat yields are insufficient use of fungicides, phosphorus deficiency, non-optimal date of sowing, poor quality of seeds, failure to apply herbicides, lack of crop rotation, and use of cultivars of unknown origin not suitable for the region. Environmental variables of great importance for the obtaining of high yields include large farm size (10 ha or larger) and good-quality soils with stable pH. This study makes it possible to propose strategies supporting more effective winter wheat production based on the identification of characteristics that are crucial for wheat cultivation in a given region.

The aim of this study was to evaluate the timeliness of winter wheat sowing on results obtained in practical production. The research material comprises results...

In the face of growing demand for food and climate change, ensuring the stability and height of crop yields is becoming a key challenge for modern agriculture. One of the solutions supporting the sustainable development of crop production is the use of certified seed. The aim of this study was to assess the impact of using certified seed on the level and stability of yields of three cereal species: winter wheat, winter triticale and spring barley, in temperate climate conditions. Data came from surveys conducted on over 8000 farms in six agroecoregions of Poland in 2021–2023. The analysis showed significantly higher yields on farms using certified seed for all species studied. Additionally, greater yield stability (lower values of Shukla variance and Wricke ecovalence) was noted in the case of using certified seeds, especially in region IV. This indicates the positive impact of certified seeds (e.g., genetic purity, health, and vigor) on the efficiency and resilience of agricultural systems. This phenomenon is of particular importance in the context of climate change and may be an important element of risk management strategies in agriculture.