Stress perception and signalling pathways between plant organs involve complex mechanisms and remain a major focus of interest. To further address the role of phytohormones in the modulation of stress perception from root-to-shoot signalling, we used ethylene-insensitive Never ripe (Nr) and auxininsensitive diageotropica (dgt) tomato mutants combined with the grafting technique. Lipid peroxidation, H 2 O 2 , chlorophyll and proline contents, and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) in non-grafted and grafted tomato mutants subjected to cadmium (Cd) were analysed. The results revealed different responses according to genotype, grafting combination and Cd application. Non-grafted hormonal mutants exhibited higher Cd content in roots than MT plants, being 39.9% in Nr and 17.7% in dgt plants, whereas in leaves, the Cd content was higher in Nr plants. In grafted plants, where the rootstocks were exposed to Cd before grafting, the MT rootstock exhibited the highest Cd content. In non-grafted plants following Cd application, roots of Nr also exhibited a decrease in Ca concentration, whilst Mg, S, Cu and Zn decreased in Nr leaves. In grafted plants, it was possible to notice peculiar differences in nutrient concentration patterns according to grafting combination and Cd application. The proline and chlorophyll contents were less affected in the hormonal mutants. In the presence of Cd, the scions of grafted plants exhibited increased antioxidant enzymes activities in response to a signal from the rootstocks. However, it was possible to associate the involvement of ethylene and auxin with the antioxidant responses because the Nr and dgt genotypes were less affected by Cd stress than their wild-type counterpart, MT. 2016 Elsevier B.V. All rights reserved.

RESUMO:Plantas ornamentais são espécies vegetais com potencial econômico utilizadas pela beleza de suas flores ou folhagens. O presente estudo teve como objetivo descrever a morfologia polínica de espécies vegetais ornamentais as quais possivelmente são visitadas por abelhas em busca do néctar. Foram estudados os grãos de pólen de seis espécies ocorrentes no campus da Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (UNESP): Caesalpinia pulcherrima (L.) Sw (Fabaceae), Cosmos sulphureus Cav (Asteraceae), Hibiscus rosa-sinensis L. (Malvaceae), Ixora coccinea L. (Rubiaceae), Lophanthera lactescens Duck (Malpighiaceae), Rhododendron simsii Planch. (Ericaceae). Por meio da unidade polínica (monâdes e tetrádes), do número e o tipo das aberturas (3-porados, 3-colporados e pantoporados), e da ornamentação da exina dos grãos de pólen(espinhosa, reticulada, estriada e psilada) foi possível identificar cada uma das espécies de plantas ornamentais aqui estudadas.Palavras-Chave: Plantas ornamentais. Grãos de pólen. Espécies melíferas. POLLEN MORPHOLOGY OF ORNAMENTAL SPECIES IN ASTERACEAE, ERICACEAE, FABACEAE, MALPIGHIACEAE, MALVACEAE AND RUBIACEAE SUMMARY:Ornamental plants are species with economic potential used by the beauty of their flowers or foliage. This study aimed to describe the pollen morphology of ornamental species which are possibly visited by bees looking for the nectar. Pollen grains of six species occurring on the campus of Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (UNESP) were studied: Caesalpinia pulcherrima (L.) Sw (Fabaceae), Cosmos sulphureus Cav (Asteraceae), Hibiscus rosa-sinensis L. (Malvaceae), Ixora coccinea L. (Rubiaceae), Lophanthera lactescens Duck (Malpighiaceae), Rhododendron simsii Planch. (Ericaceae). The pollen unit (monads and tetrads), the number and type of aperture (3-porate, 3-colporate and pantoporated) and the exine ornamentation of the pollen grains (echinate, reticulate, striate and psilate) are characters which permit the identification of each species here studied.Keywords: Honey species. Ornamental plants. Pollen grains. INTRODUÇÃOAs espécies botânicas ornamentais são plantas cultivadas por sua beleza e exuberâncias em cores, característica de suas folhagens e pelo formato dos caules ou aspectos visualmente peculiares. Essas plantas são muito apreciadas na arquitetura de interiores e no paisagismo de jardins, parques e praças (BONDI, 1990;LORENZI;SOUZA, 2001).O território brasileiro é amplamente conhecido pela marcante biodiversidade de espécies vegetais nativas, e entre estas algumas plantas ornamentais possuem alto valor comercial (SIMISKI;