Establishment of a survey method to determine rice stigma length from preparation, sampling, and preservation to measurement

The lack of a unified standard for sampling stage, preservation and measurement of stigma length is the main restriction factor for the study of stigma length trait in rice. In this study, stigma lengths were compared among four different developmental stages (T1-T4) of 30 rice materials under two environments (years) and in 10 measurement periods (D1-D120) of 3 rice materials after treatment with 6 fixatives (S1–S6), and finally the results revealed that the T3 were the best sampling stage and the S6 was the most suitable fixative for stigma length. This study thoroughly describes the process for surveying and measuring stigma length in 6 steps: preparation before sampling, flower sampling, focusing, flower dissection and imaging, obtaining measurements, and data analysis. These findings provide an outline of the methodology for the discovery, fine mapping, and functional analysis of the genes that control the stigma length trait.