Statistical Analysis for Determining Optimal Sample Size for Living Modified Organism (LMO) Seed Detection

Abstract

Problems caused by unapproved living modified organism (LMO) seeds in seed imports have emphasized determination of sample size as the most fundamental step for detecting them. Even though a guideline exists, no studies have considered the weight of seeds or validated the sample size through experiments. Hence, this study aimed at determining the optimal sample size for detecting LMO seeds by considering weights of various seeds and validating this via experiment. Binomial distribution was employed to determine the sample size for 26 kinds of seeds, and the size was validated by using 0.1% LMO seed adulteration for small and large seed types. The results indicated that the optimal sample size was more than 50, 500, and 1300 g for small, medium, and large seeds, respectively, at the 99% confidence level. At the 95% confidence level, the optimal sample size was determined as 20, 300, and 900 g, respectively. The results demonstrated 100% detection ability for both large and small seed types, validating the determined sample size. Confidence level and degree of LMO adulteration, rather than population size, were revealed as the factors determining sample size. In conclusion, this study determined and validated the effective sample size for LMO seed detection, which is highly applicable in the field of seed inspection and for quarantine agencies.