Pollen Morphology of Selected Cucurbit Species in Anambra State Markets

Cucurbits including fluted pumpkin (Telfairia occidentalis), bitter gourd (Momordica charantia), and white-seeded melon (Citrullus lanatus) are economically important vegetables and industrial crops widely traded in Anambra State markets, yet comparative pollen morphological data for Nigerian market-sourced cucurbit species are lacking. This study examined the pollen morphology of seven cucurbit species obtained from Onitsha Main Market and Eke-Awka Market in Anambra State, South East Nigeria. Mature anthers were collected, and pollen was acetolysed using the Erdtman standard method before mounting on glass slides for light microscopy. Selected samples were also sputter-coated for scanning electron microscopy imaging. Morphological features including polarity, symmetry, shape (P/E ratio), aperture type, exine sculpturing pattern, and pollen size were described and measured. Results showed that all seven species produced tricolpate pollen with varied exine ornamentation. Pollen size ranged from 47.3 µm (Cucumis sativus) to 82.6 µm (Cucurbita maxima) in equatorial diameter. Reticulate exine sculpturing was the most common pattern, while Telfairia occidentalis exhibited a distinctive fossulate-reticulate ornamentation unique among the studied species. P/E ratios ranged from 0.92 to 1.21, indicating predominantly oblate-spheroidal to prolate-spheroidal shapes. Distinctive pollen characteristics for each species were described and compiled into an illustrated pollen key. The study provides baseline palynological data applicable to taxonomic, forensic, and honey pollen analysis contexts in Anambra State.

Keywords: pollen morphology, cucurbits, palynology, Anambra State, taxonomic identification