Modeling the impacts of irrigation treatments on potato growth and development

We analyze the effects of four irrigation treatments on the growth and development of potatoes (Solanum tuberosum L.) cv Agria, using a pivot irrigation system in the province of Albacete (Castilla-La Mancha, Spain), during 2011 and 2012. We find no significant differences between irrigation treatments regarding when the phenological phases are reached. The high day and night temperatures that occurred during the second season contributed to the lengthening of the agronomic cycle. We observed maximum values of leaf area index (LAI), total dry matter (TDM), crop growth rate (CGR), and relative growth rate (RGR) in the non-stress treatments (100% and 120% of crop water requirements). The highest values of total leaf area duration (LAD) were observed in the reference treatment (100% of crop water requirements) in both seasons, while the highest values of leaf area ratio (LAR) were observed when the crop reached full coverage of the soil. In the second season, the net assimilation rate (NAR) was more notably influenced by the water deficit treatments. A water application higher than 100% of crop water requirements did not influence crop growth and development. Therefore, deficit irrigation might be appropriate in areas where water is limited.