Comparative Study of Ovule Development between Wild (<i>Passiflora foetida</i> L.) and Cultivated (<i>P. edulis</i> Sims) Species of <i>Passiflora</i> L. Provide Insights into Its Differential Developmental Patterns

• Main Authors: Archa Vijay, Ashifa Nizam, Arun Madasseril Radhakrishnan, Thattantavide Anju, Arun Kumar Kashyap, Nitesh Kumar, Ajay Kumar
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Journal of Zoological and Botanical Gardens
• Subjects: ovule development; <i>Passiflora</i>; passion fruit; pollen morphology; Passifloraceae; <i>Passiflora</i> seeds
• Online Access: https://www.mdpi.com/2673-5636/2/3/36

The ovules inside the ovary of a plant are the precursors of seeds and they are important for the perpetuation of the plants. The genus <i>Passiflora</i> L., produce fruits with numerous seeds and they have economic and medicinal value. The edible portion of the <i>Passiflora</i> are the seeds surrounded by pulp. Being the edible parts of a fruit, it is important to investigate the early development of ovules in <i>Passiflora</i> that lead to the formation of seeds after pollination. Wild relatives of the domesticated crops are increasingly being investigated for possible genetic resources that can be used for crop improvement programs. The present study was designed to investigate the comparative ovule development between a wild (<i>Passiflora foetida</i> L.) and a cultivated (<i>Passiflora edulis</i> Sims) species of <i>Passiflora</i> with an aim that it may provide important information about the common and diverging regulatory mechanisms during ovule development between the wild and the cultivated species. We also investigated the pollen morphology between the wild and cultivated species using light and scanning electron microscopy. Our results show that wild type <i>P. foetida</i> ovule growth is faster when compared with that of cultivated <i>P. edulis.</i> Furthermore, wild species harbour ovules of large size (0.14 mm²) but less in number (6) as compared to cultivated ones which show smaller size (0.05 mm²) of ovules but relatively more in number (21). The differences in ovary wall thickness were also stark between the two species. The ovary wall thickness was 0.10 mm in the wild type whereas it was 0.74 mm in cultivated species. Notable differences were also observed in diameter where the wild type (2.45 mm) reported smaller diameter than cultivated species (3.25 mm). We observed little difference in the pollen morphology between the two species.