Journal of Insect Science RESEARCH Pollination Services of Mango Flower Pollinators A. Nurul Huda,1,2 M. R. Che Salmah,1 A. Abu Hassan,1 A. Hamdan,1 and M. N. Abdul Razak3 1School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia 2Corresponding author, [email protected] 3Faculty of Plantation and Agro-technology, Universiti Teknologi MARA, 02600 Arau, Perlis, Malaysia Subject Editor: Russell Naisbit J. Insect Sci. (2015) 15(1): 113; DOI: 10.1093/jisesa/iev090 Downloaded from https://academic.oup.com/jinsectscience/article-abstract/15/1/113/2583423 by guest on 14 January 2020 ABSTRACT. Measuring wild pollinator services in agricultural production is very important in the context of sustainable management. In this study, we estimated the contribution of native pollinators to mango fruit set production of two mango cultivars Mangifera indica (L). cv. ‘Sala’ and ‘Chok Anan’. Visitation rates of pollinators on mango flowers and number of pollen grains adhering to their bod- ies determined pollinator efficiency for reproductive success of the crop. Chok Anan failed to produce any fruit set in the absence of pollinators. In natural condition, we found that Sala produced 4.8% fruit set per hermaphrodite flower while Chok Anan produced 3.1% per flower. Hand pollination tremendously increased fruit set of naturally pollinated flower for Sala (>100%), but only 33% for Chok Anan. Pollinator contribution to mango fruit set was estimated at 53% of total fruit set production. Our results highlighted the impor- tance of insect pollinations in mango production. Large size flies Eristalinus spp. and Chrysomya spp. were found to be effective pollen carriers and visited more mango flowers compared with other flower visitors. Key Words: fruit set; visitation rate; mango; pollinator efficiency; ant; fly. Pollinator species differ in morphological characteristics and behaviors mesh bags hung on the lower branches of mango trees. Meanwhile, that determine their ability to pollinate (Horsburgh et al. 2011). Various Apis cerana was kept for pollination of mango flowers in addition to insect pollinators frequent plants differently and thus vary in visitation producing honey in a small scale industry in Thailand (Wongsiri and rates, removal, and deposition of pollen within spatial as well as tempo- Chen 1995). ral scales (Sahli and Conner 2007). Paralleled with emerging need for Although mango panicles has a lot of hermaphrodite flowers (Bally multi-year and multi-site comparisons of risk assessment in conserva- et al. 2009), Usman et al. (2001) found that cross pollination had con- tion and sustainable agriculture, measuring pollinator performance has tributed to large increase in mango fruit set. Hermaphrodite flowers are become increasingly important (Ne’eman et al. 2010, Benjamin and self-pollinated but incompatibility of some pollen and stigmas cause Winfree 2014). According to Rader et al. (2009), the most effective pol- failure in mango fruit set (Singh et al. 1962, Mukherjee et al. 1968, linator species are those occurring in high abundance, actively moving Sharma and Singh 1970, Dag et al. 2006, Gehrke-Ve´lez et al. 2012). In from flower to flower (has a high visitation rate) and transferring many Chok Anan cultivar for example, Ding and Khairul Bariah (2013) de- pollen grains on the stigmas. tected some degree of self-incompatibility and hence cross pollination Pollinator efficiency or effectiveness measures the amount of pollen is necessary for a successful fruit set. deposited by an insect onto a stigma. This technique can be extremely Up to the present time, modern agriculture shows heavy reliance on difficult for many small flowers held on a panicle because of uncer- domesticated pollinators for crop production (Benjamin and Winfree tainty in locating the pollinated flowers. Moreover, pollen deposition 2014). For that matter, more focus is given to managements of pollina- depends totally on insect’s flower-visiting activity that is strictly species tors particularly honey bee (Apis mellifera) populations within agricul- specific (Howlett et al. 2011) in many flowering plants, therefore the tural environments (Abrol 2012). Unfortunately, mango flowers do not technique becomes very time consuming. Alternatively, counting pol- appear to be overly attractive to honey bee (Popenoe 1917, Usman et al. len grains on flower-visiting insects is a quicker and an easier method 2001) due to little amount of its honey production. In an attempt to im- because the pollinators can be directly captured from the flowers prove mango production in Malaysia, this study was aimed to assess (Howlett et al. 2011). Although not the best technique to measure polli- the contribution of wild pollinators to successful fertilization of mango nator efficiency, the amount of pollens carried by each insect also re- flowers by quantifying the number of fruit set produced. The second flects its effectiveness based on the foraging behavior, pollinating objective estimated the efficiencies of various pollinator species ability, and ecology of the pollinator (Borkent and Schlinger 2008, through their visitation rate on the mango flowers (Sahli and Conner O’Neill and O’Neill 2010). 2007). We presumed that the visitation rates of mango pollinators and Mango (Mangifera indica) flowers are pollinated by various insects their pollen loads were species specific and differed between male and such as wasps, ants, flies, butterflies, beetles, and bees as well as by female pollinators. wind (Bally 2006, Aliakbarpour and Che Salmah 2010). The important role of insect pollinators in mango production has been recognized in Materials and Methods many mango producing countries in the world. Sung et al. (2006) re- Study Area. The assessment of pollinator services was conducted at ported that honey bees (Apis spp.) and flies (Musca domestica and Universiti Teknologi MARA (UiTM) Perlis, Malaysia; fruit orchard Chrysomya megacephala) were responsible for successful pollination located in Arau district at coordinates of 62605900 N and 1001604700 hence good mango production in Taiwan. In India, Sharma et al. (1998) E. Two 78 m2 plots of 40 trees, 10-year-old Chok Anan-MA224 and reared Lucilia sp. (Calliphoridae) and Sarcophaga sp. (Sarcophagidae) Sala-MA164 cultivars were selected for this study during the flowering flies in their attempt to increase the abundance of pollinators in a mango season of 2014 from 28 January to 7 March. Annual temperature in the orchard. These flies were supplemented with fish or mutton pieces in district ranges between 24 and 36C with humidity of 52.6–95.6%. VC The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected] 2 JOURNAL OF INSECT SCIENCE VOLUME 15 This area receives mean daily precipitation of 16 mm and wind speed at À1 Pollen Carrying Capacity by Pollinators. A pollinator species 0.3 ms , respectively. that landed on a flower panicle was captured carefully into a glass vial All trees were fertilized regularly and a flower inducer (FlowStar (3 by 2 cm—height by diameter) containing a piece of tissue paper 250, active ingredient is Paclobutrazol 25%, Brightonmax Sdn. Bhd., soaked in 98% diethyl ether, a rapid killing agent (Jacobs et al. 2010, Malaysia) was applied 2–3 months prior to the flowering season. Howlett et al. 2011). The pollinator captured had to be killed immedi- Weeds were manually cut monthly. Out of 40 trees in each plot, 20 rela- ately to prevent pollen loss from the insect body and to prevent the tively uniform sized, flowering Chok Anan, and Sala trees were ran- insect from grooming the pollens off its body. This method of study domly selected for the assessment. offers two major assurances: (1) that it confirms the insects collected Assessment of Pollinator Performance. Pollinator performance are floral visitors; and (2) that it prevents pollen contamination among was assessed following the methods of Freihat et al. (2008) and pollinators. However, due to sampling difficulty and pollinator avail- Gemmill-Herren and Ochieng (2008). Three flower panicles from each ability, the number of replicates in this study varied among species. Chok Anan and Sala trees were chosen from 20 trees of each cultivar Pollen Atlas. A temporary pollen atlas was prepared to accurately Downloaded from https://academic.oup.com/jinsectscience/article-abstract/15/1/113/2583423 by guest on 14 January 2020 and a total of 120 panicles were used in this study. identify the mango pollen and to differentiate it from weed pollen that Pollination Treatments. Pollinator performance was assessed by the pollinators might carry. Mango pollen were collected from fully comparing the number of mango fruit set produced after the flowers bloomed flowers of several panicles and soaked in 3 ml of 75% ethanol. were exposed to three pollination treatments arranged in a completely Simultaneously, the pollen of 16 common weed flowers growing within randomized design. Each of the three flower panicles from a mango the orchard were collected and preserved in the same manner. All pollen tree used in this study was exposed to one of the three pollination treat- were observed on slides under a compound microscope Olympus ments. The first panicle was allowed to be naturally pollinated by avail- CX41 (Olympus UK Ltd., England) with 40Â magnification. Pictures able wild pollinators in the orchard throughout the flowering period. In of various pollen were captured using a digital camera (Xcam-a) addition to natural pollination, the second panicle was artificially pro- equipped with an acquisition software DigiAcquis version 2.0 (2006) vided (hand transferred) with additional pollens from different flowers by Matrix Optics (M) Sdn. Bhd, Malaysia. within the same tree (Azhar and Ithnin 2009, Bally et al.