转Bt基因抗虫棉的幼苗鉴定技术研究

（1）盆栽棉苗第一二片真叶用5000－7500mg/L卡那霉素处理，9天后观察沾有卡那霉素溶液的常规棉叶片出现明显的黄斑，而转Bt基因抗虫棉的叶片无任何症状；（2）转Bt基因抗虫棉种子接种到加有800mg/L卡 那霉素的MS培养基中，5天后，抗虫棉子叶均表现为正常绿色，而常规品种子叶全为黄色。此法对种子部门快速鉴定抗虫棉的纯度有很大的利用价值。

Study on Technique of Seedeing Identification Mark for Transgenic Bt Cotton

The technique for transgenic Bt cotton using Kanamycin as an identification marker both in the pot cultivation and in the laboratory is presented.For pot cultivation,small strips of absorbent cotton were soaked with 5000-7500mg/L Kanamycin solution to detect newly developed reversed leaf nodes 1 and 2.Nine days later,all of the leaves of the susceptible plants showed apparent yellow patches whereas the leaves of the Bt resistant plants remained green without any symptom.Kanamycin can also be used in the laboratory to test aplant resistant.Seed of trans genic Bt cotton were cultured on MS medium containing 800mg/L Kanamycin solution for five days.The cotyledons of resistant varieties remained normal green color,while those of the commercial varieties all turned yellow.This technique is especially useful for the purity test of transgenic Bt hybrid before the seed is sold.