For oil palm calli and suspension cultures, genetic variation analysis, estimation of ganome size and observation of nuclei activity is not possible via flow cytometry due to the low population of nuclei present. Hence, image cytometry or ICM method was developed to address this issue. The approach is to quantitate the chromogenic areas of the black and white nuclei images followed by calculation of integrative optical density (IOD) via image analysis software. It is important that all sample preparations and image processing are carried out in a consistent manner at all times. MPOB has developed an ICM technique using PAX-it image database and analysis software. The reference standard used in this study is a tenera seedling with nuclear DNA content of 2C=3.53 pg measured by flow cytometry, while the root tips meristematic nuclei were used as standard for image cytometry analysis. Two reference standards are required to estimate the genorame size of calli samples analysed. Reference standards nuclear DNA content must be known before the genome estimation of sample can be done.

Main Research: Maria Madon