Role of pollen production in mating success in some tropical tree species

Abstract

This study was conducted to estimate the amount of pollen produced by three entomophilous and two ornithophilous tropical woody taxa. It seeks to establish their reproductive success in relation to each other and contribution to the concentration of pollen in the air. The taxa selected were Bombax ceiba, Erythrina stricta (both ornithophilous), Lagerstroemia speciosa, Mesua ferrea and Schima wallichii (all entomophilous); which were studied in three different calendar years (2010, 2011 and 2012). M. ferrea produced the highest number of pollen grains per tree (3.85-6.60 9 10 10 ) and B. ceiba highest number of pollen grains per anther (18,610 ± 1,189.49). The pollen grains produced were estimated to be about 100 million per tree in all the studied species except M. ferrea, which produced about 10 billion pollen grains per tree. There were both good and poor production years in all the studied species. During the course of the 3-year study, B. ceiba, E. stricta and S. wallichii produced maximum number of pollen grains per tree in the year 2011, whereas maximum pollen production was observed in M. ferrea in the year 2010. However, the 2 years (2010 and 2012) mass production was observed in L. speciosa. During the high pollen production years, the fruit setting was also recorded to be high. It is interesting to point out that in E. stricta, the fruit setting was 88.5 and 91.72 % higher (i.e. 39.12 ± 3.63 %) in the year 2011 as compared to the years 2010 (4.48 ± 0.63 %) and 2012 (3.24 ± 0.49 %), respectively.

Reproductive effort and success in Bombax ceiba L. in a tropical forest of Mizoram, Indo-Burma region of North-East India

“…The high fruit and seed sets in B. ceiba may be due to the availability of high pollen and pollinator resources. The productions of pollen grains per flower and per tree in B. ceiba are very high compared to that of other bird-pollinated species such as Erythrina stricta (Khanduri et al 2015), Gmelina arborea, and Firmiana colorata (Kumar 2016). The existence of competition for other floral resources among the birds in the study locations was minimal, as the birds confined their visits only to the flowers of B. ceiba.…”

“…: 5 % (Etcheverry et al 2012), Erythrina stricta Roxb. : 4.48-39.12 % (Khanduri et al 2015), and outcrossed species, i.e., Tectona grandis Linn. f.:.…”

Flower Pollinator Interactions within Two Tropical Tree Species of Mizoram, North East India

“…found to be an important pollinator on the basis of its visitation frequency and rate. Flower size (large for L. speciosa and moderate for S. wallichii) along with large number of anthers per flower, copious pollen production (Khanduri et al, 2015) and morphological fitness of Xylocopa bee to the flowers (Khanduri, 2014) were the characteristic features of both 260 species to be adapted to pollination by Xylocopa bee. Although Xylocopa bees spent less time per flower while foraging than other species, they made frequent inter-flower and inter-tree movements.…”

Pollen limitation failing reproductive success in selected animal pollinated trees of tropical moist deciduous forest of north-eastern hill region, India

“…Flower and pollen production along with ovule number per flower was assessed by choosing ten trees each of five investigated tree species as per the method of Khanduri et al (2015). The ovule number per tree for each analysed species was calculated by multiplying the ovule number per flower with number of flowers per tree.…”

“…The complete development of floral characters along with the rate of pollen production in tree species is helpful in understanding the detailed pollination mechanism and barriers in pollination biology (Etcheverry et al, 2008;. Furthermore, the quantity of pollen production is important to (i) determine the amount of genes a population can spread (Liu et al, 2015), (ii) establish an airborne pollen forecasting (Voukantsis et al, 2010;Csépe, 2020), (iii) assess the relative density of atmospheric pollen grains of every species in a forest ecosystem (Charalampopoulos et al, 2013), (iv) predict production of seeds in a reproductive season (Allison, 1991), (v) determine the availability of pollen for pollinators to achieve pollination success (Mu et al, 2017;Khanduri et al, 2015;Sukumaran et al, 2020), and (vi) assess genetic homogeneity of a population through ample pollen exchange among individuals (Dufaÿ et al, 2008;Ramos et al, 2016).…”