Palynological studies and their implication in the compatibility of tuberose cultivars

Abstract

Determination of palynological characters of commercial cultivars is significant in determining thecompatibility and intraspecific relationship, an important criterion in tuberose breeding. The presence ofself-incompatibility and seed sterility in tuberose has greatly hindered the conventional breeding methods asconfirmed through various studies. However, regulation of the incompatibility system and the principal factorbehind it has not been thoroughly investigated. The understanding of both male and female gametophytes andtheir functioning is a prerequisite which is still a less explored area in tuberose. Seventeen tuberose genotypesstudied showed the same inclination towards viability and germination determining a positive correlation.Analysis of pollen morphology and ultra-structure using a scanning electron microscope (SEM) revealed markedvariations among the genotypes. The distinct pollen ultra-structures revealed would serve as important featuresfor classification and character identification in taxonomy. It also ascertains the pollen function as evidenced bythe shrunken pollen of genotypes previously reported as sterile. These findings are vital to fully comprehendingthe breeding systems and reproduction biology of tuberose cultivars.