白刺花硬实种子的休眠机制及休眠解除

Dormancy mechanism and breaking methods for hard seeds of Sophora davidii

  • 摘要: 目的探索白刺花硬实种子的休眠机制及解除休眠方法,为改进植物硬实种子播种育苗技术提供参考依据.方法开展白刺花种子种皮的吸水性、种胚活力及种胚萌发特性试验,分析其种皮和种胚对休眠的影响;测定其种子内源抑制物活性,利用酸腐、碱腐、激素、沸水和机械处理等方法进行破眠,筛选适宜解除白刺花种子休眠的最佳方法.结果白刺花种子剥除种皮后2 d即可充分吸胀,而完整种子吸水5 d后才达到饱和;白刺花种胚活力为73.5%,具有相对高的发芽潜力;剥离种皮的种胚发芽率最高,为72.99%,显著高于完整种子和仅具胚的种子(P<005);白刺花胚乳和胚中均含有抑制种子萌发的物质,其中50.0%胚乳浸提液可使小白菜种子萌发率降至75.85%;划破种皮破眠法可使白刺花种子发芽率达72.42%,其次是98%浓硫酸+300.0 mg/L GA3浸泡12 h处理(发芽率为57.42%).结论白刺花种皮的透水和透气性、胚乳及胚中所含的抑制物是影响白刺花种子休眠的主要因素.机械划破种皮、用98%浓硫酸(酸腐)+300.0 mg/L GA3浸泡12 h处理(激素浸泡)软化种皮能有效解除白刺花种子休眠,提高其萌发率,可在植物硬实种子播种育苗中推广应用.

     

    Abstract: ObjectiveIn order to provide reference for the improvement of sowing and seedling technology,Sopho-ra davidii seeds were used as materials to explore their dormancy mechanism and dormancy release methods.MethodWater absorption of seed coat,embryo activity and embryo germination characteristics were tested to analyze the effects of seed coat and seed embryo on dormancy. The bioassay method was used to determine the activity of seed endogenous inhibitors. Dormancy breaking methods such as acid corrosion,alkali corrosion,hormone,boiling water and mechanical treatment were used to screen the best dormancy breaking methods.ResultAfter being removed the seed coat,S. davidii seeds were in complete imbibition within 2 d,while intact seeds reached saturation in 5 d. S. davidii seeds had a relatively high germination potential,with its embryo vitality of 73.5%. The germination rate of embryo with removed seed coat was the highest(72.99%),which was significantly higher than that of intact seeds and seeds only with embryos(P<0.05). Endosperm and embryo of S. davidii contained components that inhibited seed germination. Among which,50%concen-tration of endosperm extracts could reduce the germination rate of cabbage germination rate to 75.85%. When cutting seed coat to break dormancy,the germination rate of S. davidii reached 72.42%;the second optimal method was 98%concen-trated sulfuric acid+300.0 mg/L GA3 immersing for 12 h,and the germination rate was 57.41%.ConclusionThe water and air permeability of seed coat of S. davidii seeds and endogenous inhibitor of endosperm and embryo are the main fac-tors affecting dormancy of S.davidii. The dormancy breaking methods such as cutting skin coat by machine,98%concen-trated sulfuric acid(corrosion with acid)+300.0 mg/L GA3(hormone immersion)soaking for 12 h can release dormancy effi-ciently and improve seed germination rate,which can be applied in the hard seed seedling.

     

/

返回文章
返回