Foraging Behavior of Honeybees (Apis Mellifera L.) and Ground Bumblebees (Bombus Terrestris L.) and its Influence on Seed Yield and Oil Quality of Oil Tree Peony Cultivar ‘Fengdan’ (Paeonia Ostii T. Hong et J. X. Zhang)

Abstract

<jats:title>Abstract</jats:title><jats:p>Oil peony (<jats:italic>Paeonia</jats:italic> spp.) is a new type of woody oil crop in China with a large cultivation area. Inadequate pollination is one of the main reasons for low seed yield. A pollination net room was built at an oil tree peony base, the numbers of honeybees (<jats:italic>Apis mellifera</jats:italic> L.) and ground bumblebees (<jats:italic>Bombus terrestris</jats:italic> L.) were artificially increased and the foraging behaviors and daily activities of the two bees on the plants were observed. Four different pollination methods (honeybee pollination, ground bumblebee pollination, natural field pollination and pollination without insects) were applied. The visit interval, single-flower visit time, number of single-flower visits, number of flowers visited per minute and number of stigma contacts were compared. Meanwhile, the effects of honeybee and bumblebee pollination on the oil yield and quality of peony seeds were compared. There were noticeable differences in daily activity between honeybees and ground bumblebees. Significant differences in the single-flower visit time, visit interval and visit frequency were also observed; honeybee and ground bumblebee pollination increased the seed yield of oil tree peony by 78.74% and 31.88%, respectively. Therefore, both honeybees and ground bumblebees are effective pollinators of oil tree peony. These results provide a theoretical basis for further utilization of bee resources for oil tree peony pollination.</jats:p>

Supplementary honey bee (Apis mellifera L.) pollination enhances fruit growth rate and fruit yield in Paeonia ostii (family: Paeoniaceae)

“…In the current study, bee pollination most prominently enhanced the seed quantity, leading to heavier seeds, increased oil content, and decreased seed deformity rate. But it had no significant effect on the content of UFA in seed oil, which was the same as the results of He et al (2020) [38]. Whether other oil quality parameters and seed nutritional values are similarly affected by the pollination mode demands further investigation for crops and quality measures.…”

“…For this reason, we set up a pollinator control net room supplemented with bees to evaluate pollination deficit in oil tree peony field. Previous studies have shown that A. mellifera are more efficient pollinators than Bombus terrestris on oil tree peony, and that pollination by A. mellifera can accelerate fruit development rates and yield [37,38]. This study compared the effects of different pollinator colony densities on the fruit development rate and fruit yield of oil tree peony, and provided theoretical support for further utilization of pollinator bee resources in oil tree peony field and high yield and high benefit of oil tree peony.…”

“…In addition, our pollination practice experiments showed that LDBP and HDBP have better pollinating effect and leading to much faster growth and higher fruit production compared to other treatments. Bee pollination has been reported to significantly increase seed rate and yield in oil tree peony [37,38]. Compared to non-bee-controls, long-distance and right moment outcross pollination of insects in the area with bee pollination can give crops a full opportunity for selective insemination, improve hybridization, and increase the yield and quality of fruits and seeds [9,10].…”

“…The relationship between bee visiting frequency and stigma pollen deposition on oil tree peony needs further analysis. In addition, temperature also significantly affects bees' flower-visiting activities on plants [37,38,51]. During the test, the indoor temperature of the net was higher than the outdoor temperature of the net, and when the temperature was high at noon, a large number of bees hit the top.…”

“…Inadequate pollination has been suggested as an important factor in the limiting of the oil tree peony yield. Pollen-carrying vectors play a key role in the pollination of oil tree peony because a considerable number of fruits are produced only through cross pollination [36][37][38]. Oil tree peony flowers are visited by a variety of insects including bees, ants, beetles and flies, among them, the dominant flower-visiting insects are A. mellifera, A. c. cerana, and bumble bees [36][37][38].…”