The present invention relates to three way matrix sampler that facilitate in carring out DNA based genetic purity assessment of seed lot from crop plants using three way sampling method The sampler comprise of multiple long rectangular boxes which are arranged horizontally and vertically one over the other, providing space between the horizontal and vertical boxes called retainer. The horizontally arranged rectangular boxes used for row bulking and vertically arranged boxes for column bulking, whereas the retainer boxes are used for retaining seed parts for further analysis to trace out accurate contaminant. The arrangement of rectangular boxes give rise to grid like structure to the sampler that has a potential use low- cost, rapid and accurate identification of contaminants from the seeds to be tested.
