The present invention relates to an ergonomically simple, user friendly, hand held device (1) for collecting leaf sample from crop plants at seed production field and facilitate DNA based genetic purity assessment using three way sampling technique. The device (1) primarily comprises of five components leaf sampler (2), matrix sorter (3), roll cartridge (4), tracker (5, 6) and counter (7). The leaf sampler (3) collects the leaf samples from standing crop plants and delivers to matrix sorter (3). The movable matrix sorter (3) segregates the samples collected from each plant in such a way so as to form a three way matrix. Among three leaf samples, two areused for respective row bulking and column bulking. The third leaf sample retained separately, by roll cartridge (4) for further analysis, if required. The matrix sorter (3) that contains replaceable vials (18) and roll cartridge (4) are removed from gun and DNA based genetic purity testing is carried out in DNA fingerprinting laboratory. The tracker (5, 6) in the device (1) labels the plants from which leaf samples are collected for reverse tracking purposes. The device (1) also has a counter (7) to track the number of sample collected on real time basis. Apart from facilitating seed officials to arrive decision to certify or reject the commercial seed production field, this device has the potential use in low-cost, rapid and accurate identification of contaminants/pollen shedders from hybrid seed production field.
