Pollination by Three Species of Stingless Bees (Hymenoptera: Meliponini) Increase Seed Set of Mustard (Brassica rapa L.: Brassicaceae)

Abstract

Pollination and fertilization are critical factors in horticultural cultivation to increase seed production. In this study, we measured the visiting activity and pollination of three species of stingless bees, i.e., Tetragonula laeviceps, Lepidotrigona terminata, and Heterotrigona itama in mustard (Brassica rapa). Visiting activity of stingless bees were observed in mustard plants caged by an insect screen. The observations were done visually per hour, starting from 07:00 until 16:00, using the focal sampling method. The visiting activities observed were flower handling time, foraging rate, and total visit per plant. We also measured the pollen load of each stingless bee species. Results showed the highest foraging rate occurred in H. itama (28.38 flowers/5 minutes), followed by T. laeviceps (27.88 flowers/5 minutes), and L. terminata (27.85 flowers/5 minutes), respectively. The longest flower handling time was found in H. itama (40.15 seconds), followed by T. laeviceps (35.25 seconds), and H. terminata (34.84 seconds). Whereas, the highest total visiting time occurred in H. itama (40.10 minutes), followed by T. laeviceps (37.47 minutes), and L. terminata (36.76 minutes). Heterotrigona itama has a highest pollen load (36,650 pollen grains), followed by L. terminata (26,940 pollen grains), and T. laeviceps (9,700 pollen grains), respectively. Pollination by the stingless bees increase 27-40% the number of pods per plant, 32-72% the number of seeds per pod, 32-54% of seed weight per pod, and 18-36% of seed germination of mustard.

The effects of meliponicultural use of Tetragonula laeviceps on other bee pollinators and pollination efficacy of lemon

“…In Indonesia, a total of 19 stingless bee species have been cultivated ( Buchori et al, 2022 ), and six species have been utilized as pollinators in agricultural crops, i.e ., Heterotrigona itama , Lepidotrigona terminata , Tetragonula iridipennis , Tetragonula biroi , Tetragonula clypearis , and Tetragonula laeviceps ( Putra, Permana & Kinasih, 2014 ; Alpionita, Atmowidi & Kahono, 2021 ; Asmini, Atmowidi & Kahono, 2022 ; Djakaria, Atmowidi & Priawandiputra, 2022 ; Putra et al, 2022 ; Suhri et al, 2022 ). T. laeviceps was the most commonly used species in meliponiculture in agricultural commodities such as true shallot, strawberry, okra, pummelo, and orange, and it became the main pollinator in orange orchards ( Nurdiansyah, Abduh & Permana, 2023 ).…”

“…T. laeviceps was the most commonly used species in meliponiculture in agricultural commodities such as true shallot, strawberry, okra, pummelo, and orange, and it became the main pollinator in orange orchards ( Nurdiansyah, Abduh & Permana, 2023 ). Furthermore, T. laeviceps has been successfully cultivated across several islands including Sumatera, Java, Kalimantan, Sulawesi, Bali, and Maluku, with Java emerging as the predominant cultivation site and has been shown to enhance agricultural crop pollination success ( Asmini, Atmowidi & Kahono, 2022 ; Buchori et al, 2022 ; Djakaria, Atmowidi & Priawandiputra, 2022 ). The effects of meliponiculture have been widely reported to improve quality and productivity of seeds and fruits, while to our knowledge is remains unreported whether it affects wild insect pollinators in open farming.…”