Substandard and Semi-Dwarfing Citrus Rootstocks for More Intensive, Higher-Density, and Sustainable Plantation Systems

An increasing number of intensive, dense, and sustainable citrus plantations have fostered a growing interest in addressing the future challenges of citrus crops: An increase in the world’s population, climate change, and globalization. Nutrient efficiency and the absence of vigorous citrus rootstocks are required for the success of these plantation systems. The agronomic performances of the ‘Lane Late’ orange cultivar on three substandard or semi-dwarfing citrus rootstocks (Forner-Alcaide no.5 (FA5), Forner-Alcaide no.13 (FA13), and Forner-Alcaide no.41 (FA41)) were evaluated in Spain in comparison with more traditional Mediterranean citrus rootstocks (Carrizo citrange (CA), Citrus macrophylla (MP), and ‘Cleopatra’ mandarin (CL)) under a poor mineral fertilization program over six growing seasons. FA13 and FA41 induced the smallest ‘Lane Late’ trees. Although the rootstock did not induce a significant effect on the ‘Lane Late’ yield efficiency (kg m−3), the highest values were recorded for ‘Lane Late’ on MP, CL and FA13. In this sense, FA13 showed a high productive potential (kg ha−1), given the possibility of narrowing the tree spacing (smaller tree size). Regarding the use of soil nutrients, FA13 was the most efficient citrus rootstock. Thus, FA13 stands out as the most suitable citrus rootstock for more intensive and sustainable plantation systems of the ‘Lane Late’ orange under Mediterranean conditions similar to those of this study.