POLLINATION ECOLOGY OF OVIPAROUS SEMI-EVERGREEN MANGROVE TREE SPECIES, Xylocarpus granatum KOEN AND X. mekongensis PIERRE. (MELIACEAE) AT CORINGA MANGROVE FOREST, ANDHRA PRADESH, INDIA

A. J. Solomon Raju

Abstract


Xylocarpus granatum and X. mekongensis are semi-evergreen tree species. Both species exhibit leaf fall, leaf flushing, flowering and
fruiting sequentially. They are seasonal bloomers but also flower sporadically almost throughout the year. The flowers are functionally monoecious
and exclusively pollinator-dependent. In cymes, the terminal flower is usually pistillate while the lateral ones are usually staminate. In X. mekongensis,
solitary flowers are usually pistillate. In both, the pistillate and staminate flowers produce stamens with dehiscent anthers but ovary is functional only
in the former while pollen is fertile only in the latter. Hawk moths are principal pollinators while butterflies and bees are supplementary pollinators
in both plant species. Both species fruit through geitonogamy and xenogamy and fruit set in open-pollination is very low which could be attributable
to unknown inherent regulatory mechanisms, delicate inflorescence and the production of a few pistillate flowers at plant level. The study suggests
that there is an urgent need to protect the surviving trees and take measures to restore the populations of both the species


Keywords


Xylocarpus granatum, Xylocarpus mekongensis, monoecy, hawk moths, butterflies, bees, geitonogamy, xenogamy

Full Text:

Online Preprint


DOI: https://doi.org/10.13133/2239-3129/14628

Annali di Botanica is published by the Department of Environmental Biology - University La Sapienza of Rome, Italy. The journal is printed by Sapienza Università di Roma - Centro Stampa Università.

ISSN: 2239-3129