## 3 Results and Discussion  
### Biometric Parameters of Broccoli Plants  
Differences in the biometric parameters of broccoli plants grown in the analyzed soils are presented in Figure 1. Significant differences were noted only in flower head height and the number of florets between broccoli plants grown in soil II vs. soils I and III. In comparison with plants grown in soils I and III, plants grown in soil II were characterized by the highest average SPAD index; plant height; flower head height; percentage of flower head in total plant weight; number of florets, floret height, and floret width; and the lowest number of leaves and the lowest percentage of leaves in total plant weight.  
These results indicate that soil II is most suitable for growing broccoli. Luvisols, classified as brown earth soils, cover approximately 30% of land area in Poland. The presence of sedimentary, intrusive, and porous rocks promotes leaching. Therefore, luvisols are formed under good drainage conditions from various formations, most often from loess, water dust, glacial till and sands overlying clay or heavier sandy formations. Luvisols have a well-developed profile with well-defined genetic horizons. In terms of grain size, Luvisols contain particles of silt formations, light clay, and sand underlain by clay, with no skeleton or a weak skeleton. The pH of Luvisols varies; in the present experiment, it was near-neutral, which was conducive to broccoli cultivation [20]. In soils I and III, the values of all analyzed parameters were satisfactory, but less desirable than in soil II, which implies that these types of soil were less suitable for growing broccoli. In comparison with plants grown in soil II, plants grown in soils I and III were smaller, they produced  
Figure 1: Effect of soil type on the biometric parameters of broccoli plants: a, b—various letters denote significant differences at \(p<0.05\) (Tukey’s test); I—Eutric Cambisol; II—Albic Luvisol (Arenic); III—degraded chemozem.  
smaller infloresences, smaller florets, and a higher number of leaves characterized by higher weight.  
The SPAD index of broccoli plants grown in the analyzed soils ranged from 62.5% (soil III) to 83.3% (soil II); its average value was 73.6% in plants grown in soils I and III, and 79.1% in those grown in soil II. According to [PERSON] et al. [21], the chlorophyll content of leaves (a physiological parameter) declines with decreasing nutrient concentrations in soil. In the current study, nutrient levels were similar in all examined soil types, but soil II was most abundant in nutrients.  
Plant height was lowest in soil I (50 cm) and highest in soil II (72 cm). The average plant height ranged from 51.7 cm (soil I) to 62.3 cm (soil II). Flower head height ranged from 11.5 cm (soil III) to 18.0 cm (soil II), and the average value of this parameter varied from 11.8 cm (soil III) to 16.7 cm (soil III). The flower head of broccoli plants is surrounded by leaves whose number changed within a relatively narrow range of 12 (soil II) to 15 (soils I and III). Leaves have a higher share of total plant weight than the flower head. The average ratio of these plant parts was 62:38 (soil II) to 71:29 (soil III). The flower head consists of florets whose number ranged from 8 (soil III) to 21 (soil II). Broccoli plants grown in soils I, II and III produced 13, 20 and 9 florets on average, respectively. The average flower size was largest in plants grown in soil II (height--3.3 cm, width--5.2 cm), and smallest in plants grown in soil III (height--2.4 cm, width--4.0 cm). Similar values of biometric parameters of broccoli plants were reported by [PERSON] et al. [22].