摘要： 甘暮实生系是分离世代，其性状的变异与资源品种表现同一趋势，与其无性系在诸多性状上呈强弱不同的正相关关系，这是对实生系进行早期选择利用的基础。根据结薯性可将实生系分为成薯、膨大和直根3个类型，成薯系因组合而异，受环境影响不明显。5年的研究结果证明：无性系类型间的产量性状有明显差异，从成薯类型选育高产新品系的入选率高。在此问题上和美国Granberry.M。等的认识不同。建议把我国甘薯育种的初选期提早到实生系时期，以缩短育种周期，提高育种效率。笔者认为把甘薯杂交种子培育的株系，定名为实生系，比较确切。

关键词: 甘薯实生系, 性状变异, 早期选择

Abstract: The seedling of sweet potato is a segregated generation.The variation of its characters shows not only same tendency as that of its parents,but also significant positive correlation with the derived clones in many characters.This is the base of early selection and use of sweet potato seedling.The seedling can show three types on the tuber formation:tuber,inflated root and root.The percentage of tuber formation is various in accordance with its croosing parents and is less affected by the environment.Crossing breeding practice of sweet potato has shown that various types of clone differ greatly in the yield character.So we can get more high yield varieties from the tubers.Our investigation is more feasible and different from that of M.Granberry.We should regard the seedling stage as primary selectionstage for breeding.In this way the breeding period could be shortened and the breeding procedure could be speeded.

Key words: Sweet potato seedling, Characters variation, Early selection