Potato yield and tuber quality in 75 cm and 90 cm wide ridges

In 2002, 2003, and 2004, a field trial was carried out in three locations in Slovenia, i.e., Pšata, Brnik, and Brežice with two different inter-row widths (IRWs) of 75 cm and 90 cm using three different potato cultivars (i.e., Agria, Bright, and Carlingford). The aim of this trial was to determine the influence of inter-row width (75 cm or 90 cm) with three potato cultivars on the market yield, the yield of green tubers, the cross-sectional area of the ridge, and the percentage of tubers with a hollow heart or blackspot. The trial was designed in the form of split plots with five repetitions. In the years with abundant rainfall during the period of growth (2002 and 2004), when plants completely covered the ground, the market yield at the 90 cm IRW was higher than at the 75 cm IRW. In 2003, however, the market yield was higher at the 75 cm IRW. The yield of green tubers was lower at the 90 cm IRW than at the 75 cm IRW, due to a larger cross-sectional area of the ridge ( 1000 cm^2). Thus, the soil covering of tubers in the ridge was better. The hollow heart and blackspot disorders affecting the tubers depend more on the susceptibility of a particular cultivar and the meteorological conditions during the period of growth than the IRW. The findings showed that the Agria cultivar was more susceptible to the hollow heart disorder, particularly in the years with a higher yield with thicker tubers (2002 and 2004). The Bright cultivar was affected by blackspot in 2003, the year with a lack of rainfall.