1.确定是否为杂交稻种子,区分不育系(或子一代)和保持系种子考虑到三系杂交稻不育系、保持系、子一代种子在外部形态上是完全一致的,为方便起见,本文所称杂交稻种子即指不育系、保持系和子一代种子。依据ZBB21001—87,以种子柱头残迹外露率为判定指标,凡外露率小于20%的为保持系种子;外露率大于50%的为不育系或子一代种子;外露率介于20～50%之间的,则必须取该样品的 1. To determine whether it is hybrid rice seeds, to distinguish between male sterile lines (or first generation) and maintainer lines Considering the three-line hybrid rice sterile lines, maintainer lines, the first generation of seeds in the external morphology is exactly the same, for convenience As used herein, hybrid rice seeds refer to sterile lines, maintainer lines, and seed progeny. According to ZBB21001-87, the exudation rate of seed stigma was used as the evaluation index, and those with the exposed rate of less than 20% were the maintainer seeds. The male sterile lines or seed of the first generation with the exsertion rate greater than 50% were exposed to the rate of 20-50% Between, you must take the sample