scholarly journals High species richness of native pollinators in Brazilian tomato crops

2016 ◽  
Vol 77 (3) ◽  
pp. 506-513 ◽  
Author(s):  
C. M. Silva-Neto ◽  
L. L. Bergamini ◽  
M. A. S. Elias ◽  
G. L. Moreira ◽  
J. M. Morais ◽  
...  

Abstract Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp.) are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the study agroecosystem.

2010 ◽  
Vol 24 (3) ◽  
pp. 686-696 ◽  
Author(s):  
Adriana de Oliveira Machado ◽  
Ana Palmira Silva ◽  
Helder Consolaro ◽  
Mariluza A. Granja e Barros ◽  
Paulo Eugênio Oliveira

Distyly is a floral polymorphism more common among the Rubiaceae than in any other angiosperm group. Palicourea rigida is a typically distylous species of the Rubiaceae widely distributed in the Brazilian Cerrados. This work aimed to study the floral biology and breeding system of P. rigida in order to verify if there wasasymmetry between floral morphs. The work was carried out at Fazenda Água Limpa, Brasília-DF, from 1993 to 1995; and at Serra Caldas Novas State Park-Goias and in Clube Caça e Pesca Itororó de Uberlândia-Minas Gerais in 2005 and 2006. Density, height and pin/thrum ratio were assessed for flowering individuals in all areas. Plants were investigated for differences in floral morphology, nectar production, reproductive success and site of self incompatibility reactions. Blooming period was long and concentrated during the rains. Flowers were clearly distylous and with reciprocal herkogamy. They produced nectar and lasted for a single day. In spite of differences in density and height, populations were mostly isoplethic. Nectar production varied in volume and concentration but the differences could not be associated with floral morphs. The species is self-incompatible but reproductive success was always high and independent of floral morphs. There were differences in the site of incompatibility barriers between floral morphs, which were similar to those observed for other Rubiaceae. The main floral visitors and pollinators were the hummingbirds Colibri serrirostris and Eupetomena macroura. High fruit-set indicates that the pollinators transported enough compatible pollen grains between floral morphs, despite their territorial behavior.


2019 ◽  
Vol 15 (10) ◽  
pp. 20190479 ◽  
Author(s):  
Ju Tang ◽  
Qiu-Mei Quan ◽  
Jing-Zhu Chen ◽  
Ting Wu ◽  
Shuang-Quan Huang

Bees are often considered to be effective pollinators in both agricultural and natural ecosystems but could be ineffective pollinators in that they collect large quantities of pollen for food provision but deliver little to stigmas. Male bees do not collect pollen to feed larvae, and their pollination role has been underappreciated. Here we compare pollination effectiveness, visit frequency and pollen foraging behaviour between female and male individuals of a mining bee, Andrena emeishanica , visiting a nectariferous spring flower ( Epimedium pubescens ). Female bees were observed to forage for both pollen and nectar, but male bees foraged only for nectar. Female bees had large hairy hind tibiae with conspicuous scopae, and nearly 90% of the pollen grains they collected went onto the hind legs. Male bees removed less pollen from anthers than female bees but deposited more pollen on stigmas per visit. The higher pollen transfer efficiency of male bees was due to 48.4% of pollen grains remaining ungroomed on the thorax and abdomen, available for stigma contact, but their visitation rate to flowers was much lower. Our results indicate that male solitary bees could transfer more pollen on the stigma per visit but were less important (transferred less pollen in total, because they made fewer visits per unit time) than females.


2021 ◽  
Vol 43 ◽  
pp. e55816
Author(s):  
Karina Guollo ◽  
Américo Wagner Junior ◽  
Carlos Kosera Neto ◽  
Juliana Cristina Radaelli

Studies on the Myrtaceae family are mainly distributed in floristic surveys, reproductive studies of plant communities or related to family taxonomy. Based on this, the objective of the present study was to elucidate aspects of floral and reproductive biology and, of floral visitors from Campomanesia guazumifolia (Cambess.) O. Berg., a neglected species. Information was obtained on floral morphology and morphometry, anthesis, nectary, and structures attractive to pollinators, characterization of pollinators, receptiveness of stigma and maturing of the androecium components, and characterization of the reproductive system. Sete-capote tree has hermaphrodite flowers, and the floral opening occurs mainly during the daytime. Pollen grains was the main resource offered to pollinators. The flowers had mellow sweet odor, attracting mainly native bees and Apis melifera, which was characterized as effective pollinators. The species presents high reproductive efficiency and could be considered self-compatible; however, fertilization also occurs by cross-pollination.


2018 ◽  
Vol 12 (2) ◽  
pp. 425-435
Author(s):  
Carlos De Melo e Silva-Neto ◽  
Anna Clara Chaves Ribeiro ◽  
Flaviana Lima Gomes ◽  
Jordana Guimarães Neves ◽  
Aniela Pilar Campos de Melo ◽  
...  

The use of agrochemicals is harmful to bees visiting agricultural crops, reducing production gains from pollination, but the effect of fungicides on these bees is not known. The objective of this study was to verify the effect of bee visitation influenced by different fungicides on the tomato crop and on the deposition of pollen grains on the stigma, number of seeds, mass and fruit size. The experiment was conducted with 10 treatments: (T1) control treatment, without application of agrochemicals; (T2 and T3) Bacillus subtilis in different application frequencies; (T4) copper hydroxide; (T5) B. subtilis and copper hydroxide; (T6) acibenzolar-S-methyl; (T7) (trifloxystrobin+tebuconazole) and B. subtilis; (T8) copper hydroxide+Mancozeb; (T9) propineb+(trifloxystrobin+ tebuconazole); (T10) (trifloxystrobin+tebuconazole)+B. subtilis+copper hydroxide. The presence of the pollination mark on the flower, the pollen load of the stigmas, the number of seeds per fruit, and the size and mass of the fruits were determined in each treatment. Subsequently, the mortality rate of Melipona quadrifasciata (Hymenoptera, Apidae) exposed to four fungicides (trifloxystrobin+tebuconazole; manganese and zinc; copper hydroxide; Bacillus subtilis) was estimated. The mortality rate of M. quadrifasciata over 24 h of evaluation was higher in the treatments with copper hydroxide and trifloxystrobin+tebuconazole (75 and 50%, respectively). The mortality rate was lower in the treatments with manganese and zinc and Bacillus subtilis and in the control treatment. The treatments with trifloxystrobin+tebuconazole reduced the presence of bite marks on the flowers and of pollen grains on the flower stigma. The fruits of the control treatments and treatments with B. subtilis and copper hydroxide were larger and had greater mass, as compared to other agrochemicals. Thus, a higher number of pesticide applications on the tomatoes reduced bee visitation rates to the flowers and, consequently, reduced the amount of pollen grains deposited on the stigmas, also reducing the fruit production. 


2015 ◽  
Vol 87 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Lívia C. Simioni ◽  
Rosilda M. Mussury ◽  
Munir Mauad ◽  
Daiane M. Dresh ◽  
Fabricio F. Pereira ◽  
...  

Despite the economic importance of Crambe abyssinica, the present study is the first report on bees that occur with this species, and could aid in developing alternative methods for controlling insect pests without seriously impacting pollinators. The present study examined the following questions: (1) Which species are potential pollinators of C. abyssinica? (2) How do environmental conditions influence pollinator visitation fluctuations? Insects were sampled on a weekly basis between 08:00 and 16:00 during five weeks of flowering. When the results of analyses of variance were significant, the data was adjusted using regression equations at a 5% level of probability; the environmental variables were examined using Pearson's correlation coefficient. Apis mellifera, Geotrigona mombuca, Exomalopsis (Exomalopsis) fulvofasciata, Plebeia sp. and Dialictus sp. were observed visiting C. abyssinica flowers. A. melliferaand G. mombucawere observed to be potential pollinators, with the former demonstrating visitation peaks during flowering weeks II and IV at 12:00 and 08:00, respectively and the latter visiting during weeks III and IV at 12:00 and 10:00, respectively. Environmental factors such as temperature, relative humidity, and wind speed have different effect on the activity of bees.


2011 ◽  
Vol 82 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Rafael Nunes Zardo ◽  
Raimundo Paulo Barros Henriques

2020 ◽  
Vol 126 (3) ◽  
pp. 377-386 ◽  
Author(s):  
Nicola Delnevo ◽  
Eddie J van Etten ◽  
Nicola Clemente ◽  
Luna Fogu ◽  
Evelina Pavarani ◽  
...  

Abstract Background and Aims Ant–plant associations are widely diverse and distributed throughout the world, leading to antagonistic and/or mutualistic interactions. Ant pollination is a rare mutualistic association and reports of ants as effective pollinators are limited to a few studies. Conospermum (Proteaceae) is an insect-pollinated genus well represented in the south-western Australia biodiversity hotspot, and here we aimed to evaluate the role of ants as pollinators of C. undulatum. Methods Pollen germination after contact with several species of ants and bees was tested for C. undulatum and five co-flowering species for comparison. We then sampled the pollen load of floral visitors of C. undulatum to assess whether ants carried a pollen load sufficient to enable pollination. Lastly, we performed exclusion treatments to assess the relative effect of flying- and non-flying-invertebrate floral visitors on the reproduction of C. undulatum. For this, we measured the seed set under different conditions: ants exclusion, flying-insects exclusion and control. Key Results Pollen of C. undulatum, along with the other Conospermum species, had a germination rate after contact with ants of ~80 % which did not differ from the effect of bees; in contrast, the other plant species tested showed a drop in the germination rate to ~10 % following ant treatments. Although ants were generalist visitors, they carried a pollen load with 68–86 % of suitable grains. Moreover, ants significantly contributed to the seed set of C. undulatum. Conclusions Our study highlights the complexity of ant–flower interactions and suggests that generalizations neglecting the importance of ants as pollinators cannot be made. Conospermum undulatum has evolved pollen with resistance to the negative effect of ant secretions on pollen grains, with ants providing effective pollination services to this threatened species.


2020 ◽  
Vol 51 (1) ◽  
pp. 363-386 ◽  
Author(s):  
Rachel L. Vannette

Flowers at times host abundant and specialized communities of bacteria and fungi that influence floral phenotypes and interactions with pollinators. Ecological processes drive variation in microbial abundance and composition at multiple scales, including among plant species, among flower tissues, and among flowers on the same plant. Variation in microbial effects on floral phenotype suggests that microbial metabolites could cue the presence or quality of rewards for pollinators, but most plants are unlikely to rely on microbes for pollinator attraction or reproduction. From a microbial perspective, flowers offer opportunities to disperse between habitats, but microbial species differ in requirements for and benefits received from such dispersal. The extent to which floral microbes shape the evolution of floral traits, influence fitness of floral visitors, and respond to anthropogenic change is unclear. A deeper understanding of these phenomena could illuminate the ecological and evolutionary importance of floral microbiomes and their role in the conservation of plant–pollinator interactions.


2010 ◽  
Vol 40 (11) ◽  
pp. 2204-2214 ◽  
Author(s):  
E. R. Palupi ◽  
J. N. Owens ◽  
S. Sadjad ◽  
Sudarsono ◽  
D. D. Solihin

Teak ( Tectona grandis L.) is believed to have been introduced from India 400–500 years ago and there appear to be no old-growth natural forests. However, Indonesia has many teak plantation forests and 40%–50% of seeds for reforestation come from seed orchards and the remainder from plantations. In both, flower and fruit abortion results in low fruit set and thus seed production. We investigated flower and fruit development in a clonal seed orchard in East Java in 1999 and 2001 using cross- and open-pollinated trees. The rates of abortion using cross-pollinations showed a similar pattern but were lower than for open-pollinations. The highest rate of abortion in cross- and open-pollinations was during pollination and fertilization, ranging 11%–23% and 31%–32%/day, respectively, less during fruit initiation (5%–6% and 6%–8%/day) and the lowest was during fruit maturation (<0.5%/day). Cross-pollinations increased fruit production by 10-fold compared with open-pollinations. About 30% of flowers were pollinated with an average of five pollen grains per stigma in open-pollinations. Pollen viability varied among clones and time of day but was not affected by position of flowers in an inflorescence. We conclude that low pollination success and low pollen viability are major causes for low fruit production in teak and are related to insect pollinators.


2021 ◽  
Vol 11 ◽  
Author(s):  
Daniele Del Buono ◽  
Luca Regni ◽  
Alberto Marco Del Pino ◽  
Maria Luce Bartucca ◽  
Carlo Alberto Palmerini ◽  
...  

Salinity is one of the most impacting abiotic stresses regarding crop productivity and quality. Among the strategies that are attracting attention in the protection of crops from abiotic stresses, there is the use of plant biostimulants. In this study, Megafol (Meg), a commercial plant biostimulant, was tested on olive plants subjected to severe saline stress. Plants treated with salt alone showed substantial reductions in biomass production, leaf net photosynthesis (Pn), leaf transpiration rate (E), stomatal conductance (gs), and relative water content (RWC). In addition, samples stressed with NaCl showed a higher sodium (Na+) content in the leaves, while those stressed with NaCl and biostimulated with Meg increased the potassium (K+) content in the leaves, thus showing a higher K+/Na+ ratio. Salinity caused the accumulation of significant quantities of hydrogen peroxide (H2O2) and malondialdehyde (MDA) due to decreases in the activity of antioxidant enzymes, namely superoxide dismutase (SOD – EC 1.15.1.1), ascorbate peroxidase (APX – EC 1.11.1.11), guaiacol peroxidase (GPX – EC 1.11.1.9), and catalase (CAT – EC 1.11.1.6). When olive plants under saline stress were biostimulated with Meg, the plants recovered and showed physiological and biochemical traits much improved than salt stressed samples. Finally, Meg exhibited Ca2+-chelating activity in olive pollen grains, which allowed the biostimulant to exert this beneficial effect also by antagonizing the undesirable effects of hydrogen peroxide on Ca2+ metabolism.


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