白桦雄花发育异常突变体的成熟花药及花粉特征

目的雄花发育异常突变体是研究花器官发育及基因功能的理想试材,树木的花发育异常突变体更为罕见。本文旨在研究一种白桦雄花发育异常突变体的成熟花药及花粉特征。方法以该种突变体为试材,对野生型(WT)、突变体的2种花序(NLM、MM)及其花药花粉进行了观察分析、活力检测、扫描电镜观察。结果突变体的2种花序散粉量极少,部分花药不开裂;WT、NLM、MM 3种花粉的I-KI染色率分别为99.1%、64.1%和68.9%;花粉萌发率分别为88.9%、1.63%和1.86%。DAPI染色发现突变体花粉粒出现皱缩、膨大、变形等现象。上述结果表明, 突变体花粉活性较低,萌发率差。扫描电镜观察发现,突变体花粉大小不一,萌发孔孔盖较小且严重内陷。结论白桦雄花发育异常突变体的表型特征分析为白桦的花药花粉发育机理,雄性不育分子机制的研究提供了重要的基础资料。 

Mature anther and pollen characteristics of male inflorescence mutant in Betula platyphylla

ObjectiveMale inflorescence mutants are ideal materials for studying floral organ development and genetic function, and the male floral mutant of tree is uncommon. This paper aims to study the mature anther and pollen characteristics of male inflorescence mutant in Betula platyphylla.MethodUsing this mutant as a test material, the inflorescence and their anther pollen of wild-type (WT) and mutants (NLM, MM) were observed, analyzed, detected for viability, and examined by scanning electron microscopy.ResultThe results showed that there was few pollen dispersal quantity for 2 types of inflorescence of mutant and partial anther was not cracking; the I-KI dyeing rates of WT, NLM and MM were 99.1%, 64.1% and 68.9%, respectively, and the pollen germination rates were 88.9%, 1.63% and 1.86%, respectively. DAPI staining showed that the pollen grains of the mutant were shrinkage, swelling and deformation. The results indicated that the mutants had lower pollen activity and germination rate. Moreover, scanning electron microscopy showed that the pollen operculum was smaller and seriously trapped.ConclusionThis research not only provides important theoretical basis for the study of the pollen development mechanism of the anther of Betula platyphylla, but also plays significant importance in exploring the molecular mechanism of male sterility.