Characterization of Wheat Plants based on Morphological Parameters and Productivity Elements at the Ear – Case Study

Abstract

The study aimed to characterize wheat plants based on morphological parameters and describe through mathematical models the variation of some productivity elements in the wheat ear. The field experiments were located within the ARDS Lovrin, agricultural year 2024 - 2025. The biological material was represented by the 'Dacic' wheat variety sown at a density of 280 kg/ha. The culture was in a non-irrigated system. Conventional cultivation technology was provided, with fertilization at the level 30 kg a.s./ha nitrogen (ammonium nitrate, applied in spring, in two doses; a.s. active substance) and 120 kg a.s./ha phosphorus (concentrated superphosphate, applied in autumn). At crop maturity, 20 plants were randomly sampled. Plant height (PH, cm), spike length (EL, cm), spikelet number (SpkN), grain number per spike (GNE), spike weight (EW, g) and grain weight per spike (EGW, g) were determined. Moderate variability was recorded for the EGW parameter (CV_EGW = 21.32) and low variability for the other parameters. The variation of the GNE parameter was evaluated in relation to PH, EL and SpkN, and the variation of EGW was analyzed in relation to EL, SpkN and GNE, considered as variables in different combinations. The quadratic regression analysis generated mathematical models that described the variation of GNE under conditions of R² = 0.587, p = 0.019 (based on PH, EL), R² = 0.682, p = 0.004 (based on PH, SpkN), respectively R² = 0.677, p = 0.004 (based on EL, SpkN). In the case of the EGW parameter, the regression analysis led to mathematical models with R² = 0.760, p = 0.001 (based on SpkN, GNE), R² = 0.351, p = 0.247 (based on EL, SpkN), and respectively R² = 0.695, p = 0.003 (based on EL, GNE). 3D graphical models and isoquant format described the distribution of GNE and EGW in relation to the considered parameters. Statistical reliability was recorded for the obtained models, except for the variation of EGW in relation to EL and SpkN. Based on the moderate and low values ​​of the regression coefficient, it can be appreciated that under the study conditions, the variation and interdependence of the parameters considered at the level of the wheat ear, the 'Dacic' variety, was influenced to a considerable extent by environmental factors.