Effect of the cyanogenesis on the incompatibility of crow clones of Hevea spp. budded onto IPA 1

• Autor(a) principal: Moraes, Larissa Alexandra Cardoso
• Data de Publicação: 2002
• Outros Autores: Moraes, Vicente Moraes Haroldo de Figueiredo, Moreira, Adônis
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Brasileira (Online)
• Texto Completo: https://seer.sct.embrapa.br/index.php/pab/article/view/6421
• topic: enxertia; glicosídeo; linamarase; metabolismo

The objective of this work was to verify the role of the rubber tree cyanogenic glycosides in the incompatibility of the IPA 1 clone (Hevea brasiliensis) with budded crowns of clones of other species of Hevea. The activity of the following enzymes involved in the cyanide metabolism was determined: b-glycosidase, b-diglycosidase and b-cyanoalaninesynthase (b-CAS). These enzymes were studied in the stem bark of the clones IPA 1, Fx 3864 and Fx 4098. Clones of high and low cyanogenic potential (HCN-p) were crown budded on IPA 1, and the development of the budded plants was recorded. The HCN-p of young and mature leaves of other crown clones known as compatible or incompatible was determined. The b-CAS activity of IPA 1 was found to be as low as in non-cyanogenic plants while it was very high in Fx 3864 and intermediate in Fx 4098. IPA 1 displayed higher b-glycosidase and b-diglycosidase activities, which, together with the very low b-CAS activity, determine the extreme sensitivity to cyanide of this clone. Crown clones of low HCN-p in young leaves were compatible, as well as those with high HCN-p in young leaves, but keeping it high in the mature. In incompatible clones the HCN-p is reduced in mature leaves. These evidences support the hypothesis that the incompatibility is caused by the translocation of linustatin, from the leaves to the stem of IPA 1. The incompatibility symptoms resemble some aspects of the Tapping Panel Dryness, suggesting a relationship of TPD with cyanogenesis.