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.