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1.
J Econ Entomol ; 115(3): 706-714, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35526117

RESUMO

Beekeeping contributes to poverty reduction in many developing countries, and in addition, provides pollination services for sustainable crop production. In Nepal, management practices associated with beekeeping are poorly characterized, and so the potential for this sector to further contribute to livelihood development remains unclear. This study sought to examine and identify factors associated with production efficiency and financial profitability of beekeeping with the aim of enhancing economic gains for Nepali beekeepers. Our study included a sample of 150 respondents from more than twenty commercial beekeeping districts across the Terai and mountainous regions of Nepal. Profitability of beekeeping with the European honeybee (Apis mellifera) Linnaeus, 1758 (Hymenoptera: Apidae) and the Asian honeybee Apis cerana Fabricius, 1793 (Hymenoptera: Apidae) was quantified and disaggregated according to several variables, including hive-derived products produced, marketing strategy employed, number of beehives managed, and postharvest management practices. Our results showed that the different types of management practices adopted (such as number of beehives kept, colony multiplication, supplementary feeding, month of honey harvesting, and marketing approach) significantly influenced the productivity and economic profitability of beekeeping. Our results also revealed that professional supports, such as the availability of subsidies and training, were key factors to enhance productivity. As a whole, this study provides insight into the biological factors and management practices associated with higher economic returns from beekeeping. This work can help guide policymakers and professional support agencies to expand commercial beekeeping for sustainable livelihood development in Nepal and beyond.


Assuntos
Criação de Abelhas , Mel , Animais , Abelhas , Humanos , Nepal , Polinização
2.
Neotrop Entomol ; 49(4): 511-524, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32162245

RESUMO

Most cultivars of apple trees are highly dependent on insects for successful pollination and fruit production. In this study, we evaluated the insect diversity in apple orchards of southern Brazil and verified whether or not there is a relationship between the diversity of insect visitors and the characteristics (weight, seed number, and symmetry) of the fruits of 'Fuji' and 'Gala' apples produced by the orchards. We also evaluated the diversity of insects on flowering weeds within apple orchards and compared it with the apple flowers. Diversity of anthophilous insects was low, in general, and differed between the regions. Furthermore, regarding insect diversity, orchards were grouped by management system: organic orchards were more similar to each other than to conventional orchards. The insect diversity of weed flowers was higher than apple flowers, but insect abundance was greater on apple flowers, suggesting that weeds may increase insect diversity within apple orchards and may sustain pollinators. We found a positive effect of insect diversity on the number of seeds of 'Fuji' apples and of honeybee abundance on their weight, suggesting that honeybee management is important in the studied areas. In contrast, we found no significant effect of insect diversity and abundance on 'Gala' apple characteristics. Despite this, the analyses of the seeds of 'Gala' apples indicate that the orchards may suffer a pollination deficit, which could be overcome by improving insect pollination. These results reinforce previous findings that insect diversity is important for apple yield, but its influence varies with cultivar.


Assuntos
Frutas , Insetos/classificação , Malus , Polinização , Animais , Brasil , Produtos Agrícolas , Flores/fisiologia , Insetos/fisiologia , Sementes
6.
Braz. j. biol ; 74(4): 787-794, 11/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-732330

RESUMO

Planning the artificial pollination of agricultural crops requires knowledge of the floral biology and reproductive system of the crop in question. Many studies have shown that rapeseed (Brassica napus Linnaeus) is self-compatible and self-pollinated, but its productivity may be increased by insect visitation. In the present study, the floral biology and the response of productivity to insect visitation of two rapeseed cultivars (Hyola 420 and Hyola 61) were analyzed and compared in three regions of Rio Grande do Sul, Brazil. The rapeseed flowers presented three stages during anthesis, with the time periods varying between the cultivars. Both cultivars are self-compatible, but free visitation of insects increased productivity by 17% in the Hyola 420 cultivar and by approximately 30% in the Hyola 61 cultivar. Therefore, it is concluded that the cultivar Hyola 61 is more dependent on insect pollination than Hyola 420.


O planejamento de polinização dirigida nas culturas agrícolas requer o conhecimento da biologia floral e do sistema reprodutivo da cultura em questão. Muitos estudos mostram que a canola (Brassica napus Linnaeus) é auto compatível e auto polinizada, no entanto, sua produtividade pode ser aumentada pela visita por insetos. Nesse estudo, a biologia floral e a resposta da produtividade à visita por insetos de duas cultivares de canola (Hyola 420 e Hyola 61) foram analisadas e comparadas em três regiões do Rio Grande do Sul, Brasil. As flores de canola apresentaram três fases durante a antese, havendo variação no período de tempo de acordo com a cultivar. Ambas as cultivares são auto compatíveis, mas a livre visita por insetos aumentou a produtividade em 17% na cultivar Hyola 420 e cerca de 30% na cultivar Hyola 61. Dessa maneira, concluímos que a cultivar Hyola 61 é mais dependente da polinização entomófila que a Hyola 420.


Assuntos
Animais , Brassica napus/crescimento & desenvolvimento , Brassica napus/parasitologia , Flores/crescimento & desenvolvimento , Insetos/fisiologia , Polinização/fisiologia , Brasil , Insetos/classificação , Fatores de Tempo
7.
Braz J Biol ; 74(4): 787-94, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25627587

RESUMO

Planning the artificial pollination of agricultural crops requires knowledge of the floral biology and reproductive system of the crop in question. Many studies have shown that rapeseed (Brassica napus Linnaeus) is self-compatible and self-pollinated, but its productivity may be increased by insect visitation. In the present study, the floral biology and the response of productivity to insect visitation of two rapeseed cultivars (Hyola 420 and Hyola 61) were analyzed and compared in three regions of Rio Grande do Sul, Brazil. The rapeseed flowers presented three stages during anthesis, with the time periods varying between the cultivars. Both cultivars are self-compatible, but free visitation of insects increased productivity by 17% in the Hyola 420 cultivar and by approximately 30% in the Hyola 61 cultivar. Therefore, it is concluded that the cultivar Hyola 61 is more dependent on insect pollination than Hyola 420.


Assuntos
Brassica napus/crescimento & desenvolvimento , Brassica napus/parasitologia , Flores/crescimento & desenvolvimento , Insetos/fisiologia , Polinização/fisiologia , Animais , Brasil , Insetos/classificação , Fatores de Tempo
8.
Braz J Biol ; 70(4): 1075-81, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21180917

RESUMO

Brassica napus Linnaeus is considered a self-compatible crop; however, studies show that bee foraging elevates their seed production. Considering bee food shortages during the winter season and that the canola is a winter crop, this study aimed to evaluate the foraging behaviour of Apis mellifera Linnaeus, 1758 regarding those flowers, and to verify if it presents adequate behaviour for successfully pollinating this crop in Rio Grande do Sul State. The study was carried out in a canola field, in Southern Brazil. The anthesis stages were morphologically characterised and then related to stigma receptivity and pollen grain viability. Similarly, the behaviour of A. mellifera individuals on flowers was followed, considering the number of flowers visited per plant, the amount of time spent on the flowers, touched structures, and collected resources. Floral fidelity was inferred by analysing the pollen load of bees collected on flowers. The bees visited from 1-7 flowers/plant (x = 2.02; sd = 1.16), the time spent on the flowers varied between 1-43 seconds (x = 3.29; sd = 2.36) and, when seeking nectar and pollen, they invariably touched anthers and stigmas. The pollen load presented 100% of B. napus pollen. The bees' attendance to a small number of flowers/plants, their short permanence on flowers, their contact with anthers and stigma and the integral floral constancy allows their consideration as potential B. napus pollinators.


Assuntos
Abelhas/fisiologia , Brassica napus/crescimento & desenvolvimento , Polinização/fisiologia , Animais , Comportamento Animal , Brasil , Estações do Ano
9.
Toxicon ; 39(9): 1343-51, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11384722

RESUMO

The number of accidents caused by injection of the venom of Lonomia obliqua caterpillars in Southern Brazil has increased in the last years. Even though this kind of envenomation has an important social and medical impact, nothing is known about the cellular structures responsible for the production and secretion of this venom. Here we identify and analyse morphological structures possibly responsible for the production and secretion of the active principles of the venom, as well as the histological relationship of these structures with the urticating spines of L. obliqua. Detailed microscopic observations showed that: (a) L. obliqua has a complex tegument, with several cuticular specializations, (b) there are no pores along the tegument neither in the spines and (c) the spines bear a hollow canal--where the venom is deposited--and an area that can be easily broken when touched, releasing the venom. Histological and histochemical techniques revealed that: (a) there is no single gland cell that produces the venom, (b) a secretory epithelium, composed of cells containing vesicles that increase in size and number as they reach the apical region, underlies the tegument and the spines and is responsible for secretion of the venomous substances and (c) the venom is deposited in the subcuticular space and at the tips of the spines.


Assuntos
Venenos de Artrópodes/química , Mariposas/metabolismo , Animais , Venenos de Artrópodes/metabolismo , Células Epiteliais/metabolismo , Glândulas Exócrinas/química , Glândulas Exócrinas/metabolismo , Glândulas Exócrinas/ultraestrutura , Larva , Microscopia Eletrônica de Varredura
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