Article

Prop root anatomy of Philodendron bipinnatifidum Schott (Araceae)

Acta Botanica Brasilica (Impact Factor: 0.55). 12/2001; 15(3):313-320. DOI: 10.1590/S0102-33062001000300003

ABSTRACT O imbé (Philodendron bipinnatifidum) é amplamente distribuído no Brasil. As plantas possuem raízes escoras, pelas quais se apóiam no suporte, e raízes de absorção, as quais crescem sob o solo e obtêm os nutrientes. Este estudo apresenta informações sobre a anatomia das raízes escoras enfatizando a organização do sistema vascular e a origem dos ductos resiníferos. Na região suberificada, as raízes eram amarronzadas e na porção apical eram esbranquiçadas. A partir do ápice radicular, foram retiradas amostras de 0,3cm de comprimento totalizando 1,2cm. Da região suberificada, foram retiradas amostras com 0,5cm. As amostras foram fixadas em solução de Karnovsky, desidratadas em série etílica e infiltradas em resina glicol metacrilato. Na região situada entre 1,0 e 3,0mm do ápice radicular, a raiz escora possuía uma coifa plurisseriada cujas células apresentavam paredes anticlinais sinuosas. A protoderme era unisseriada. Os ductos de resina, de origem esquizógena, diferenciavam-se entre as células do meristema fundamental. O cilindro vascular apresentava-se lobado. Na região suberificada, a epiderme era substituída pelo súber estratificado, o parênquima cortical possuía várias camadas de células entre as quais ocorriam ductos resiníferos de origem esquizógena e muitos idioblastos secretores. O cilindro central possuía organização estelar "anômala" e desprovida de medula.

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