天山鸢尾种子休眠与萌发特性研究

Studies on Seed Germination Characteristics of Iris loczyi Kanitz

对天山鸢尾(Iris loczyi)种子休眠与萌发特性进行了研究。结果表明:天山鸢尾种子生活力为90.00%。种皮的透水、透气性差及致密的胚乳是天山鸢尾种子萌发困难的主要原因之一;天山鸢尾种子的抑制物质主要存在于种皮中,其次为种仁,但外种皮对种子萌发没有抑制作用,也不存在萌发抑制物;珠孔端胚乳也是造成天山鸢尾种子休眠的主要因素。H2SO4处理对其种子萌发无促进作用。GA3、6-BA、NAA、KNO3和H2O2对打破天山鸢尾种子休眠无作用。单一因子温度不能打破天山鸢尾种子休眠,需采用综合措施,且综合处理能有效地提高天山鸢尾种子的发芽率,最适处理为GA3浓度100mg/L+低温沙藏8周+去种孔端胚乳+变温30℃/20℃,其种子发芽率为66.67%。

The seed dormancy and germination characteristics of Irisloczyi.were studied in this paper.The results showed that the seed viability was 90.00%;Poor air and water permeability of seed coat,as well as the dense endosperm,was the main factors of poor germination in I.loczyi.Inhibitors of seed were mainly existed in seed coat,then seed kernel.The seed germination was not inhibited by out integument of I.loczyi,which gave no inhibitors.The restriction caused by tipped micropylar endosperm was another main factor to induce dormancy of I.loczyi seeds.The seeds germination rate of I.loczyi had not been increased by adding concentrated sulfuric acid;GA3,NAA,6-BA,KNO3 and H2O2had no obvious effects on breaking seed dormancy of I.loczyi.The seed dormancy of I.loczyi could not be broken by single temperature factor,but comprehensive treatment worked.Comprehensive treatment was effectively to improve seed germination rate of I.loczyi,the optimal treatment was 100 mg/L GA3,followed by cold stratification period of 8 weeks,then de-dipped micropylar endosperm and cultivated under alternating temperature 30℃/20℃,the seed germination rate was 66.67%.