BROCCOLI (BRASSICA OLERACEA L. VAR. ITALICA) YIELD AS AFFECTED BY SOIL FERTILITY PARAMETERS IN NORTHERN GREECE
Twenty-four fields were cultivated with broccoli (cv. Marathon) during the period late summer - early winter of 2003 in Northern Greece. Broccoli heads were harvested, weighed separately for each field and processed as frozen product. Nitrogen was applied at a rate of 250 kg/ha and additional nutrients were applied as required by soil analysis. Yield ranged from 3.15 to 14.42 t/ha, mean yield was 8.12 t/ha with a standard deviation of 3.11 t/ha. The soils were characterized as medium to moderate heavy in texture with its basic parameters being as follows: a) Physicochemical properties: pH 6.82-7.96, electrical conductivity 0.32-1.69 mmhos/cm, organic matter content 0.35-2.51%, CaCO3 content 0.50-10.10% and b) Nutrient elements (mg/kg): P 9.26-81.44, K 110.0-470.0, Ca 136.0-1100.0, Mg 22.8-186.0, B 0.22-0.77, Mn 3.80-24.90, Zn 0.61-6.73, Fe 4.36-28.00 and Cu 0.39-4.00. Multiple regression analysis revealed that yield was significantly related with the studied soil parameters (r2 = 0.942). Furthermore, stepwise variable selection program showed that the parameters pH, electrical conductivity and Cu were the most important variables for yield prediction (r2 = 0.923). Especially, pH and Cu had a positive effect on broccoli yield, while electrical conductivity, a negative one.
Almaliotis, D., Bladenopoulou, S., Chatzissavvidis, CH. and Karagiannidis, N. (2007). BROCCOLI (BRASSICA OLERACEA L. VAR. ITALICA) YIELD AS AFFECTED BY SOIL FERTILITY PARAMETERS IN NORTHERN GREECE. Acta Hortic. 729, 409-413
vegetables, soil fertility, minerals, fertilization, multiple regressions