Investigating the Relationship between Ounces and Kernel Percentage in Four Commercial Pistachio Cultivars (Kaleh-Ghoochi, Ahmad-Aghaei, Owhadi and Akbari)

The purpose of the present study was to investigate the relationship between ounce and kernel% (kernel to shell) with each other and other quantitative and qualitative indices of the kernel and nut in Iranian commercial pistachio cultivars. Four pistachio cultivars including Kaleh-Ghoochi, Ahmad-Aghaei, Owhadi and Akbari, which constitute the main pistachio cultivar, are selected in five ounces and then the relationship among the commercial indices of the kernel and nut was determined by different statistical methods. The results of this study showed that the quantitative and qualitative indices related to kernel and nut morphology reviled a significant decrease with increasing number of nut per ounce. The nut and kernel length (r= .0.433) showed a higher relationship with ounce as compared to the other traits. The suture opening and shell thickness had the highest coefficient of variation (C.V.), indicating a high range of variations between different nuts in one ounce. In this study, the indices related to the kernel were less effective than the nut on ounce index. The kernel hectoliters, which is a valuable commercial index for determining the quality and health of the kernel, is not significantly different in ounces, indicating no significant difference in the kernel quality of Iranian commercial cultivars with an increase in ounces. The kernel% was significantly affected (P<0.01) by ounce in all four cultivars. In this study, the highest kernel% was observed in Owhadi (57.39), Ahmad-Aghaei (56.35), Kaleh-Ghoochi (53.92) and Akbari (53.30) cultivars, respectively. Therefore, Owhadi had the highest and Akbari had the lowest kernel%. The findings indicated that kernel% in the round cultivars was more affected by the shell thickness and the stretched cultivars by the kernel. The results showed that there was a negative correlation (r= 0.439) between ounces and kernel% in evaluated cultivars.