Published online by Cambridge University Press: 19 September 2007
Introduction. Research was conducted at the Pistachio Research Institute in Rafsanjan, Iran, to evaluate the effects of ‘Badami’ (Pistacia vera L.), ‘Sarakhs’ (wild P. vera) and ‘Beneh’ (P. mutica F. & M.) seedling rootstocks on the nut quality of ‘Owhadi’, ‘Kalleh-ghuochi’ and ‘Ahmad-aghaie’ pistachio cultivars. Twenty-year-old trees of these nine rootstock/scion combinations were used in a two-year study done in 2003 and 2004. Materials and methods. Growth parameters [trunk cross-sectional area (TCA), tree height, canopy diameter, shoot growth, leaf area and number of suckers], yield parameters (cumulative yield and yield efficiency), and nut quality (blankness, splitting, nuts per ounce and weight of 100 nuts) were measured. Results and discussion. TCA was significantly lower on ‘Sarakhs’ rootstock than on the two other rootstocks and ‘Sarakhs’ was the least vigorous among the tested rootstocks and gave the lowest leaf area of scion cultivars. ‘Sarakhs’ rootstock consistently influenced the formation of the highest number of suckers. ‘Badami’ rootstock allowed us to obtain the greatest cumulative production and yield efficiency, the lowest blankness of pistachio nuts, and the highest percentage of splitting of pistachio nuts. Conclusion. Our study showed that genetic variability among pistachio rootstocks may influence scion vigour, yield, extent of shell splitting, blankness and nut weight.