No abstract

Basella alba is an underutilized vegetable with ethnobotanical importance used for culinary as well as medicinal purposes in many parts of the world. Morphological characterization and chromosome studies of the mitotic and meiotic cells of the green stemmed and the red-stemmed B. alba was carried out with a view to filling the knowledge gaps that exist in their morphological characterization and also to provide insightful information on their chromosome numbers and meiotic behaviour. The B. alba accessions studied were characterized with respect to their habit, leaves, inflorescence, fruits and seeds. Mitotic and meiotic studies were carried out on the Basella accessions using standard techniques. The morphological studies revealed significant differences between the green-stemmed and red-stemmed Basella alba with respect to the green/red colour of their stems, colour of the flower bud apex, mean plant height at flower bud initiation, mean leaf length, mean leaf width, mean petiole length, mean flower per spike, mean fruit length and mean fruit diameter. The cytological study revealed a chromosome number of 2n=4x=44 for both the green-stemmed and the red-stemmed B. alba studied. It also revealed the occurrence of chromosomal aberrations such as stickiness and precocious migration of chromosomes to the poles during meiosis, which could lead to irregular chromosome segregation that could result in chromosome instability and aberrant meiotic products within the species.

Basella alba is an important, underutilised vegetable rich in vitamins and consumed in many parts of the world. However, the reproductive biology of this species is insufficiently known; therefore, this study was performed aiming to fill this knowledge gap. Although green-stemmed and red-stemmed Basella alba share a lot of reproductive attributes in common, the obtained results showed differences in their flower bud apex colour, anther colour, spike colour, days to 50% flowering, plant height at flower bud initiation and the mean number of flowers per spike. In both forms, the floral attributes favoured self-pollination. However, the possibility of cross-pollination among them due to the activities of pollinators such as ants, moths, butterflies and bees suggests a mixed mating system. Furthermore, both forms attained sexual maturity at varying periods, thus indicating the existence of a temporal prezygotic barrier between them and limiting the chances of their hybridisation. They could also be responsible for the ability to remain in their distinct forms even when they exist together in the same habitat.