Sex Determination in Leave of Date Palm (Phoenix doactylifera) on the Juvenile Vegetative Phase between Tissue Culture and Seeding by using LC-QTOF-MS Technique

The knowledge of identify key metabolites for the purpose of separating female date palm from the male counterparts in the juvenile vegetative phase will help farmers make accurate investment decisions for date palm cultivation to generate the maximum profit. The research aims to develop metabolomics technique to identify both genders by using the high resolution liquid chromatography-quadrupole time-offlight-mass spectrometer (LC-QTOF-MS) together with multivariate statistical analysis. The study was conducted by extraction of leaves from 2-year old date palms with known sex which were propagated in both tissue culture and conventional seeding in 50%(v/v) methanol. The result of LC-QTOF-MS demonstrated that the date-palm leaves obtained by tissue culture technique could be clearly distinguished from the seedgrown date-palm leaves because the analysis of heatmap patterns clearly showed a reduction of 11 unique metabolites (e.g., metabolites 593.1359, 2370552, 366.9829 Da). This data confirmed that female date palms grown from tissue culture were metabolically different from male date palms. On the other hand, it is very difficult to distinguish the gender of date palms grown from seeds. Only when intensive analysis of metabolite fingerprints was performed, it revealed that dates grown from female seeds differed from males due to the differences in gibberellin and artocarpin as well as an unknown metabolite of 439.0743867 Da.