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Vliv atmosférických srážek na otevírání prašníků / The role of atmospheric precipitation in anther dehiscenceKampová, Anna January 2020 (has links)
Anther dehiscence is an important process taking place at the end of the plant life cycle. This process consists of various follow-up steps which result in anther opening and pollen grains exposure. Good timing of the anther dehiscence must be synchronized with pollen grains maturation and flower opening. Atmospheric precipitation is a high-risk factor for the anther dehiscence. Male fitness of plants can be reduced when anthers open during poor weather conditions. The aim of this study was to investigate the effect of atmospheric precipitation, rain and dew, on Arabidopsis arenosa anther dehiscence. We observed that rain and dew led to a postponed final stage of the anther dehiscence. This caused delayed pollen release. The effect of aqueous and nonaqueous environment on the anther dehiscence was also tested. Experiments with transformation of A. arenosa using Agrobacterium tumefaciens were performed. Key words: anther dehiscence, flower opening, rain, dew, Arabidopsis arenosa, Agrobacterium tumefaciens, transformation
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Influência da área de reserva legal sobre a biologia da polinização de SOLANUM LYCOPERSICUM L. híbrido pizzadoro (SOLANACEAE)Trevizor, Ana Mayumi Hayashi 28 March 2014 (has links)
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Previous issue date: 2014-03-28 / Financiadora de Estudos e Projetos / It is estimated that approximately 73 % of the world crops are pollinated by a bees. The constant alteration of habitats has led to the decline of pollinators, which may reflect limitations in the quantity and quality of the fruits and seeds grown, becoming one of the biggest problems when it comes to agricultural production. Studies with agricultural crops and their pollinators may contribute in seeking proposals that combine agriculture and conservation of forest fragments. The general objective of this work was to study aspects of Solanum lycopersicum L. hybrid Pizzadoro pollination. The specific objectives were: 1) verify if the floral morphology influences the behavior of the pollinator visits, 2) evaluate the richness of pollinating bees and pollinators at different distances from the Legal Reserve area, 3) compare the efficiency of three species of bees pollination in two treatments: spontaneous self-pollination, and pollination under natural conditions. The study was conducted on a conventional tomato cultivation in the municipality of Estiva Gerbi, Sao Paulo. Flowers were collected and observed under a stereomicroscope and scanning electron microscope. Efficiency was compared between Apis mellifera, Augochloropsis sp. and Exomalopsis sp. by Spears index. Observations and sampling were made in situ at 50, 100 and 150 meters from the Legal Reserve. It was found that the anther dehiscence is longitudinal and that the efficiency of pollination by A. mellifera (0.72) was similar to Exomalopsis sp. (0.85) and greater than Augochloropsis sp. (0.22). It is considered that the success of A. mellifera is associated with the floral morphology. Eleven species of insects, of which 7 were considered pollinators were found. Fifty eight floral visits were recorded, out of which 24 in quadrant A (50 m), 13 in B (100 m) and 21 in C (150 m), with A. mellifera dominant with 62.1% of visits, followed by Augochloropsis sp. and Oxaea flavescens both with 10.3%, Exomalopsis sp. with 6.9 %, Allograpta sp. with 5.2 % ,Bombus sp. with 3.4 % and Xylocopa sp. 1.7 %. The data indicates that the Legal Reserve played a key role in providing pollinators for tomato crops and therefore emphasizes the need for conservation and restoration of forest fragments to assist in increasing crop production. / Estima-se que aproximadamente 73% das plantas cultivadas mundialmente sejam polinizadas por alguma espécie de abelha. A constante alteração de habitats vem provocando o declínio de polinizadores, que pode refletir em limitações na quantidade e qualidade dos frutos e sementes cultivados, constituindo-se em um dos maiores problemas quando se trata de produção agrícola. Estudos com culturas agrícolas e seus polinizadores podem contribuir na busca de propostas que conciliem agricultura e conservação de fragmentos florestais. O objetivo geral do presente trabalho foi estudar aspectos relacionados com polinização de Solanum lycopersicum L. híbrido Pizzadoro. Os objetivos específicos foram: 1) verificar se a morfologia floral influencia no comportamento de visita do polinizador; 2) avaliar a riqueza de abelhas polinizadoras e visitantes florais em diferentes distâncias da área de Reserva Legal; 3) comparar a eficiência de três espécies de abelhas na polinização em dois tratamentos: kautopolinização espontânea, e a polinização em condições naturais. O estudo foi realizado numa área de cultivo convencional de tomate no município de Estiva Gerbi, São Paulo. Foram coletadas flores e observadas em estereomicroscópio e microscópio eletrônico de varredura. Foi comparada a eficiência de Apis mellifera, Augochloropsis sp. e Exomalopsis sp. pelo teste de Kruskal-Wallis. Observações e coletas foram feitas in situ a 50, 100 e 150 metros da RL. Verificou-se que a deiscência da antera é do tipo longitudinal e que não houve diferença entre as espécies de abelhas, ou seja, o número de sementes produzidas não depende da espécie de abelha. Considera-se que o sucesso de A. mellifera esteja associado à morfologia floral. Foram encontradas 11 espécies de insetos, das quais 7 foram consideradas polinizadoras. Foram registradas 58 visitas florais; dessas, 24 no quadrante A (50 m), 13 no B (100 m) e 21 no C (150 m), sendo A. mellifera dominante com 62,1% das visitas, seguida de Augochloropsis sp. e Oxaea flavescens ambos com 10,3%, Exomalopsis sp. com 6,9%, Allograpta sp. com 5,2%, Bombus sp. com 3,4% e Xylocopa sp. com 1,7%. Os dados indicam que a RL desempenhou um papel fundamental no fornecimento de polinizadores para a cultura de tomate e, por isso, enfatiza-se a necessidade de conservação e restauração de fragmentos florestais para auxiliar no aumento da produção da cultura.
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