Screening of antifungal activity of extracts from 21 species of medicinal plants against Penicillium italicum of citrus fruits and the efficacy of Cynanchum atratum ethanol extracts for control

Authors Chen Chuying; Peng Xuan; Chen Yuhuan; Wan Chunpeng; Chen Jinyin

Journal Acta Phytophylacica Sinica , ,:

Abstract To develop new-style plant-derived preservative for citrus fruits,the antifungal activity of extracts from 21 species of Chinese medicinal herbs against citrus blue mold Penicillium italicum was investigated by cylinder-plate method,and the efficacy of extracts of selected Cynanchum atratum Bunge to control the disease on navel orange was also determined. The results showed that ethanol extracts of C. atratum,Ocimum basilicum L.,Brucea javanica (L.) Merr.,Terminalia chebula Retz and Stephania cepharantha Hayata efficiently inhibited the growth of P. italicum with inhibition zones all over 26 mm in diameter. Among all the selected medicinal plants,the extract from C. atratum showed the best antifungal activity, of which the inhibition zone diameter,minimum inhibitory concentration and minimum fungicidal concentration were 38.39 mm,3.13 mg /mL and 6.25 mg /mL,respectively,similar to those of treatment with prochloraz. Likewise,treatments with the extract at 25 mg /mL and prochloraz produced similar efficacies of disease control with 35.93% and 36.37%,respectively. The ethanol extract of C. atratum significantly inhibited the mycelial growth and caused cytoplasm leakage and morphological changes including swollen,curliness and deformity in hyphae of P. italicum. The peroxidase activity of navel orange decreased,while those of phenylalanine ammonia-lyase and chitinase increased upon treatment with the extract. The results indicate that the ethanol extract of C. atratum is effective in blue mold disease control and may be further developed into plant-derived preservative for citrus fruits.

Species covered 罗勒(变种) Ocimum basilicum 诃子 Terminalia chebula 鸦胆子 Brucea javanica 白薇 Cynanchum atratum 金线吊乌龟 Stephania cepharantha