Alternative Control of Alternaria Brown Spot in Tangerine

作     者：Antonio Manoel Da Silva Filho Élida Barbosa Corrêa Alisson Queiroz Moura Juan Manuel Anda Rocabado Antonio Manoel Da Silva Filho;Élida Barbosa Corrêa;Alisson Queiroz Moura;Juan Manuel Anda Rocabado

作者机构：Phytopathology Laboratory of the State University from Paraiba (UEPB) Lagoa Seca Brazil Department of Agricultural Engineering Federal University of Campina Grande (DEAG/UFCG) Campina Grande Brazil Center University Araras Dr. Edmundo Ulson Araras Brazil Laboratory of Electronic Microscopy Federal University of the Recô ncavo of Bahia (UFRB) Cruz das Almas Brazil 

出 版 物：《Agricultural Sciences》 (农业科学（英文）)

年 卷 期：2020年第11卷第12期

页      面：1217-1231页

学科分类：09[农学] 0904[农学-植物保护] 

主　　题：Alternaria alternata f. sp. citri Momordica charantia Psidium guajava Vegetal Extracts Vegetal Tinctures 

摘      要：Alternaria brown spot is considered the main disease of tangerines in the State of Paraiba. The objective of work was to evaluate vegetal tinctures from bitter melon (Momordica charantia) and guava (Psidium guajava) leaves, as an alternative control for Alternaria brown spot in tangerine. The effects of vegetal tinctures were tested in leaves and fruits (detached) of tangerine “Dancy inoculated with tangerine pathotype of Alternaria alternata. The effect of tinctures on mycelium growth and spore germination of the pathogen was tested. Tinctures at 20% concentration promoted reduction of disease severity. A reduction of 80% in the diameter of leaf lesions was observed for bitter melon tinctures and 75.3% for guava tinctures. In fruits, the reduction was 48.4% (bitter melon tinctures) and 43.3% (guava tinctures). Guava tinctures, starting at a concentration of 5%, inhibited 100% of mycelium growth of tangerine pathotype of A. alternata, while the use of bitter melon tinctures inhibited 100% of mycelium growth starting at a concentration of 10%. The greater sensitivity to tinctures observed when these were added to the culture medium when compared to inoculation in leaves and fruits may be explained due to the higher exposition of the pathogen to the active principle when the vegetal tinctures were added to the culture medium, than when tinctures were sprayed over the vegetal surface in fruits and leaves. The number of germinated spores decreases 76.7% and 82% when using tinctures from guava and bitter melon (20%). Tinctures from bitter melon and guava are potential tools for alternative management of the Alternaria brown spot in tangerine “Dancy.