Developmental and ultrastructural effect of Uncaria tomentosa (Willd.) DC extract on the paprika Capsicum annuum L.

Abstract The effect of liana ( Uncaria tomentosa L.) extract on paprika (Capsicum annuum L.) cv. Koźlak. development, leaf ultrastructure and yielding were studied under greenhouse conditions. Uncaria extract was supplied before flowering of plants by two manners: to the soil or leaves. It is shown that the effect of Uncaria extract on paprika was dependent on the concentration and the way of supply of the preparation to plant. In the case of extract supply to the soil, distinct growth inhibition of plants and ultrastructural manifestations of senescence were observed. Simultaneously, acceleration of flowering and fruiting were noticed. The phenomena mentioned above caused the lower yield of paprika fruits compared to the control. In the case of extract supply to leaves, high acceleration of flowering and fruits maturation of paprika were observed. Spraying of leaves with Uncaria extract resulted in an increase of fruits yield compared to the control.