Alterações anatômicas do sistema vascular em porta-enxertos de videira

Abstract

Resumo -O objetivo deste trabalho foi avaliar a ocorrência de alterações do padrão de vascularização de porta-enxertos de videira. Utilizaram-se os genótipos Paulsen 1103 (Vitis berlandieri x Vitis rupestris), MGT 101-14 (Vitis riparia x V. rupestris) e SO4 (V. berlandieri x V. riparia). O experimento foi conduzido em delineamento de blocos ao acaso com três tratamentos (genótipos) e dez plantas por parcela. Avaliaram-se as variáveis de crescimento vegetativo dos porta-enxertos e, por meio de cortes histológicos realizados no ápice, na porção mediana e na base dos ramos, as anatômicas. As diferenças no sistema vascular tornaram-se maiores do ápice para a base dos ramos. Os genótipos SO4 e Paulsen 1103 apresentaram maior área de xilema na base dos ramos, 2,61 e 2,51 mm 2 , respectivamente, e maior diâmetro dos vasos, 45,8 e 47,2 µm, respectivamente, em comparação ao MGT 101-14 que apresentou 1,60 mm 2 de xilema e 34,1 µm de diâmetro dos vasos. Ocorreram modificações também na frequência dos vasos. A área de xilema, o diâmetro e a frequência dos vasos estão relacionados ao crescimento vegetativo dos porta-enxertos. As alterações do padrão de vascularização podem ser um critério para a escolha de porta-enxertos, em razão de sua influência sobre os processos fisiológicos.Termos para indexação: Vitis, fisiologia, padrão de vascularização, videiras, xilema. Anatomic changes of the vascular system in grapevine rootstocksAbstract -The objective of this work was to evaluate the occurrence of changes in the vascularization pattern of grapevine rootstocks. The genotypes Paulsen 1103 (Vitis berlandieri x Vitis rupestris), 101-14 MGT (Vitis riparia x V. rupestris), and SO4 (V. berlandieri x V. riparia) were used. The experiment was carried out in a randomized complete block design with three treatments (genotypes) and ten plants per plot. Vegetative growth of grapevine rootstocks and anatomic variables, by the analysis of histological sections performed in the apex, middle, and base portion of the stem, were evaluated. The differences in the vascular system became larger from the apex to the base. The SO4 and Paulsen 1103 genotypes had higher xylem area in the base of the stem, of 2.61 and 2.51 mm 2 , respectively, and larger diameter of vessels, of 45.8 and 47.2 µm, respectively, in comparison to 101-14 MGT that showed 1.60 mm 2 for xylem and 34.1 µm for vessel diameter. Modifications also occurred for the frequency of vessels. The xylem area, diameter, and frequency of vessels are related to rootstock vegetative growth. Vascularization pattern changes may be a criterion for the choice of rootstocks, due to their effect on the physiological processes.Index terms: Vitis, physiology, vascularization pattern, grapevines, xylem. IntroduçãoA escolha do porta-enxerto de videira fundamenta-se em características como resistência a pragas e doenças, características do solo (calcários, ácidos, salinos), variedade de videira a ser cultivada e condições de cultivo (Miele et al., 2009). Além destas características, sabe-se que os porta-...

Quality and antioxidant potential of ‘BRS clara’ and ‘Arizul’ grapes influenced by rootstocks in a tropical region

“…Also, this choice characterize other factors such as resistance to pests and diseases and compatibility with canopy cultivar and growing conditions. However, there are few studies on scion/rootstock interaction that focus on physiological responses and their repercussion on fruit quality (Santarosa, 2016).…”

Monocotyledonous vascular bundles characterized by image analysis and pattern recognition

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In vitro callus co-cultivation strategy for prospecting growth regulators to induce in vivo grapevine graft union

“…Several factors linked to the genetic origin of these scion/rootstock combinations, such as anatomical and biochemical contrasts, may be modulating the level of effect of each GR formulation on callogenesis and grafting quality. Among the anatomical factors, it is noteworthy that the variation in the vascularization pattern can occur even between cultivars of the same species, mainly in the xylem area and in the number of vessel elements (SANTAROSA et al, 2016). For example, the vascular alignment between the scion and rootstock interferes with chemical and molecular transport, affecting the functioning of the graft union (VAHDATI et al, 2010).…”