Palynological investigations in Jasminum spp.

Abstract

The present investigation was carried out at the Department of Floriculture and Landscape Architecture, Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore during 2017-2019. The study involved nine jasmine genotypes, four falling under the commercially cultivated types and five belonging to underutilized species or ‘lesser-known species’. The study was undertaken to investigate and document the palynological parameters of jasmines which could serve as a reliable reference for future jasmine breeding programmes. The palynological investigations were carried out using Scanning Electron Microscopy (SEM), haemocytometry, acetocarmine test, and in vitro pollen germination. The pollen morphology analysis indicated wide variation among the species for the shape of the pollen grain, ranging from tricolpate to prolate; the exine ornamentation was reticulate in all the genotypes. Pollen output was the highest in J. rigidum (28,660 pollen/flower) and the lowest in (625 pollen/ flower) in J. sambac cv. Ramanathapuram Gundumalli. The maximum pollen germination rate and pollen tube length were recorded in J. rigidum.