Format: ORAL

Ritu Yadav1, Vinita Gowda2

1 PhD student, Tropical Ecology and Evolution (TrEE) Lab, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh, India. 2. Associate professor, Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh, India

Flowering plants have a diversity of mechanisms for reproduction. Both asexual and sexual modes represent alternative reproductive mechanisms that plants may adopt in order to counter temporally or spatially variable environments. In plants, it is common to find that a single individual may resort to either mode, resulting in a mixed reproductive strategy. Our study is focused on the genus Globba L., which is a tropical understory herb. It is known for its high diversity in reproductive strategies, with presence of both sexual (andromonecy) and asexual (bulbils) modes of reproduction. The objective of our study is to investigate ecological factors that may have shaped the evolution of bulbils in Globba, and to show how this strategy may have helped the genus diversify in the Asian tropical understory. I will specifically address the evolutionary significance of asexual reproduction and how it is an efficient reproductive strategy. To study the evolution of bulbils in this genus, we sampled Indian Globba spp. from the states of Northeast India and Western Ghats and used sequences from NCBI for the remaining species. A Bayesian phylogenetic analysis using BEAST was carried out on nuclear and chloroplast data set with 89 species. To study the ecological and physiological relevance of asexual reproduction in Globba, we also carried out field experiments for 10 species across 15 populations. Our results suggest that the presence of bulbils is an ancestral state and may have evolved multiple times in the genus Globba. We also identified obligate asexual taxa differed in their ecological characteristics (such as population size, pollinator visitation rate, natural fruit set, and physiological compatibility). The disproportionate distributional success of obligate asexual species suggested that asexual reproduction by bulbils is clearly an advantageous and an efficient reproductive strategy in some Globba species.