Flowering of Australia's Rainforests

The Flowering of Australia’s Rainforests provides a comprehensive introduction to the pollination ecology, evolution and conservation of Australian rainforest plants, with particular emphasis on subtropical rainforests and their associated pollinators. This significantly expanded second edition includes new information on the impact of climate change, fire, fragmentation and invasive species. Rainforests continue to be a focus of global conservation concern, not only from threats to biodiversity in general, but to pollinators specifically. Within Australia, this has been emphasised by recent cataclysmic fire impacts, ongoing extreme drought events, and the wider consideration of climate change. This second edition strengthens coverage of these issues beyond that of the first edition. The Flowering of Australia’s Rainforests makes timely contributions to our understanding of the nature and function of the world’s pollinator fauna, plant-reproduction dependencies, and the evolutionary pathway that has brought them to their current state and function. Illustrated with 150 colour plates of major species and rainforest formations, this reference work will be of value to ecologists and field naturalists, botanists, conservation biologists, ecosystem managers and community groups involved in habitat restoration.

Relative Abundance and Foraging Behaviour of Pollinator Fauna on Niger (Guizotia abyssinica Cass.) and its Influence on Yield

Niger (Guizotia abyssinica Cass.) is one of the important oilseed crop of Southern and Central India. Niger is a completely cross pollinated crop brought about by insects, referring to the importance of pollination, the study was undertaken to know the role of pollinators in Niger ecosystem and its influence on yield parameters. The present investigation was carried out during 2016-2017 at the Zonal Agricultural Research Station, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore, India. In this study, fourteen species of flower visitors were observed during the flowering period belonged to orders Hymenoptera (9 species), Lepidoptera (4 species) and Diptera (1 species). The overall diversity of pollinators was more during morning hours (8.00 AM to 11.00 AM) and gradually decreased after 12.00 PM to 5.00 PM. Among different pollinator species Apis florea was more abundant with 41.46% followed by Apis dorsata and Apis cerana. The peak activity of A. florea was observed at 11.00 AM followed by A. cerana at 10.00-11.00 AM and A. dorsata was at 11.00 AM. The highest number of probing was observed in A. florea (7.52) followed by A cerena and A. dorsata. The time (sec) taken for one probing was highest in A. florea followed by A cerena and A. dorsata. The number of filled seeds observed 37.66% less in caged condition when compare with open pollination and there was significant decrease in the yield in caged condition when compare with open pollination indicating importance of pollinators specifically honey bees for successful production of Niger.

Patterns of floral morphology in relation to climate and floral visitors

Background and Aims The diversity of floral morphology among plant species has long captured the interest of biologists and led to the development of a number of explanatory theories. Floral morphology varies substantially within species, and the mechanisms maintaining this diversity are diverse. One possibility is that spatial variation in the pollinator fauna drives the evolution of spatially divergent floral ecotypes adapted to the local suite of pollinators. Another possibility is that geographic variation in the abiotic environment and local climatic conditions favours different floral morphologies in different regions. Although both possibilities have been shown to explain floral variation in some cases, they have rarely been competed against one another using data collected from large spatial scales. In this study, we assess floral variation in relation to climate and floral visitors in four oil-reward-specialized pollination interactions. Methods We used a combination of large-scale plant and pollinator samplings, morphological measures and climatic data. We analysed the data using spatial approaches, as well as traditional multivariate and structural equation modelling approaches. Key Results Our results indicate that the four species have different levels of specialization, and that this can be explained by their climatic niche breadth. In addition, our results show that, at least for some species, floral morphology can be explained by the identity of floral visitors, with climate having only an indirect effect. Conclusions Our results demonstrate that, even in very specialized interactions, both biotic and abiotic variables can explain a substantial amount of intraspecific variation in floral morphology.

Filling the Egyptian pollinator knowledge-gap: checklist of flower-visiting insects in South Sinai, with new records for Egypt

Flower visitor surveys were conducted across the St Katherine Protectorate of South Sinai, Egypt, between April-July 2012 and 2013. We present a checklist of 112 species of flower visitors belonging to the orders Coleoptera, Diptera, Hemiptera, Hymenoptera and Lepidoptera. The Hymenoptera were the most diverse group of flower visitors, consisting of 69 species from eight families: Apidae (14), Colletidae (8), Crabronidae (10), Halictidae (13), Megachilidae (19), Scoliidae (1), Sphecidae (2) and Vespidae (2). We recorded nine species that were endemic to the region and thirteen that were new to the Egyptian fauna, including one new to science, Hylaeus oliviae Dathe, 2015. The study provides a valuable initial checklist of pollinators within the St Katherine Protectorate, but the description of novel species and the high proportion of new records for Egypt suggest that species numbers are likely to be underestimated. We highlight the need for future research into Egyptian pollinator fauna, particularly within the St Katherine Protectorate where endemic bees are still being described.

Natural hybridization patterns between widespread Calanthe discolor (Orchidaceae) and insular Calanthe izu-insularis on the oceanic Izu Islands

Natural hybridization often occurs between insular and widespread species, and investigating these hybridization patterns is important in improving our understanding of the evolution of insular plant species. To this end, we studied the floral morphology and genetic structure of the widespread species Calanthe discolor, the insular closely related species C. izu-insularis and their putative natural hybrids on Honshu Island (mainland) and the Izu Islands (oceanic islands), Japan, using microsatellite markers. Natural hybridization probably occurred on all the investigated Izu Islands in Japan, although C. izu-insularis was morphologically and genetically different from C. discolor. Bumblebees and other relatively large bees are not distributed in the Izu Islands and therefore natural hybridization would have occurred via pollination by relatively small solitary bees that are pollinators of both Calanthe spp. We also showed that in the islands more remote from the mainland, the proportions of insular C. izu-insularis increased and the floral morphologies of both species changed. The results suggested that insular C. izu-insularis evolved on the Izu Islands and the widespread C. discolor adapted to the poor pollinator fauna on oceanic islands.

Insect pollinators' diversity of rapeseed (Brassica campestris var. toria) in Chitwan, Nepal

The abundance and diversity of rapeseed insect flower visitors were assessed by using insect pan traps, sweep net and visual observations at different blooming stage of rapeseed at Jutpani VDC, Chitwan district, Nepal during 2012-013. The pollinator fauna of rapeseed included twenty one species from six different insect orders. Hymenopteran (77.95%) species were the most abundant insects visiting rapeseed followed by Diptera (12.23%) and Lepidoptera (3.49%). Honeybees were the dominant group of pollinators and among honeybees, Apis mellifera L. was the most dominant one (36.34%) followed by Apis florea F. (12.45%), Apis cerana F. (11.14%) and Apis dorsata F. (5.68%). The higher abundance and diversity of pollinators were observed at 12:00 to 1:00 pm and the diversity was related to the crop blooming stage. Therefore, pollinator's friendly cultivation practices should be followed for conservation and management of insect pollinators for higher production and productivity of rapeseed crop under Chitwan condition. Journal of the Institute of Agriculture and Animal Science. Vol. 33-34, 2015, 73-78

Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees

The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees.