Antifungal activity and bio-stimulating effect generated by two botanical extracts in Alpinia purpurata and Heliconia wagneriana cultivation

Abstract

Fusarium sp. and Capnodium sp. are phytopathogen fungi causing scab and sooty mold in Alpinia purpurata and Heliconia wagneriana, economically important tropical flowers for farmers in the area of Concordia, Ecuador. They constitute a threat to their high occurrence on stems, foliage, and flowers, mostly influenced by environmental factors. In the present study, plant extracts from Ocotea quixos (Lam.) and Piper carpunya (Ruiz & Pav.) were used as an alternative to agrochemicals. Extracts were obtained by two methods, and serial dilutions were tested on each isolated’s phytopathogen in vivo. Results showed that macerated extracts in cane alcohol and the herbal distillates from P. carpunya and O. quixos present good preventive and regulator level on Fusarium sp. and Capnodium sp. at the laboratory level. On this basis, these extracts were implemented in the field in two doses with chemical and absolute controls. An arbitrary visual scale was put in a place to assess the level of control on phytopathogens. This scale ranged from 1 to 4 and determined visual damage caused in the stems, leaves, and flowers of A. purpurata and H. wagneriana. Six applications were done, once a week, in two cuts in each flower. The control effect or severity of the infection was evaluated every 15 days. The results showed an inhibitory biological activity of extracts against Fusarium sp. and Capnodium sp. and a bio-stimulating effect on flower spikes.