SAMPLING METHODS FOR LOQUAT FRUIT QUALITY ANALYSIS

Quality traits of matured fruits from 15-year-old plants of loquat (Eriobotrya japonica Lindl.) ‘Dahongpao’ were examined and used as statistical materials for comparison of different sampling methods in order to increase accuracy of quality analysis. The results showed that the method of stratified sampling in accordance with acceptable sunlight degree of plant parts was better than that simple random sampling and systematic sampling. By this stratified sampling method, the smallest coefficient of variation was obtained from fruit weight, flesh recovery and titratable acidity in fruit inside the canopy, and also for total soluble solids in peripheral fruit. A sample size of at least 25, 51 and 96 fruits is required for a precision degree of 90, 95 and 99%, respectively.