Diversity among Isolates of the Tangerine Pathotype of Alternaria alternata  

作　　者：Andréa Celina Ferreira Demartelaere Luciana Cordeiro do Nascimento Cristina O.Marinho Marciano Costa Nunes Patrícia Clemente Abraao Rommel S.S.Gomes Monica Danielly de Mello Oliveira Larissa Almeida Mirelly M.Porcino Caroline Vargas e Silva Wilza C.O.Souza 

机构地区：[1]Programa de Pós-Graduacao em Agronomia,Departamento de Fitotecnia e Ciencias Ambientais,Universidade Federal da Paraíba,Areia,Brazil

出　　处：《American Journal of Plant Sciences》2018年第2期196-215,共20页美国植物学期刊（英文）

基　　金：received a PhD fellowship from National Counsel of Technological and Scientific Development(CNPq);a post-doctoral fellowship from CAPES-EMBRAPA;a PhD fellowship from Coordenacao de Aperfeicoamento de Pessoal de Nível Superior(CAPES);a fellowship Programa Institucional de Bolsas de Iniciacao Científica(PIBIC)from CNPq.

摘　　要：The tangerine pathotype of Alternaria alternata is the aetiological agent of Alternaria brown spot on tangerines. In the state of Paraíba, Brazil, its occurrence on “Dancy” tangerine trees is associated with genetic aspects as well as the influence of environmental conditions on reproduction and dissemination within and between populations. The aim of the present study was to evaluate the diversity of isolates of this pathogen using morphophysiological and molecular markers. For the analysis of mycelial growth and sporulation, 30 isolates from different locations were examined at 24-hour intervals until the seventh day, when the spores were quantified. The 30 isolates were characterised based on molecular markers (ISSR) and genetic similarity (Jaccard index). A factor arrangement was used: 30 isolates, four media (ODA, PDA, LEA and V8), three light regimes (continuous dark, alternating light and continuous light) and three temperatures (15°C, 25°C and 35°C), with 12 repetitions. Groups 1, 2 and 3 presented low genetic variability. Group 4 showed high genetic variability of the isolates obtained from the Massaranduba (state of Paraíba-Brazil) producing region and higher mycelial growth and sporulation of A. alternata. The continuous light regime and the temperature 25°C in PDA and V8 media were the ideal conditions for the mycelial growth and sporulation, respectively, of the isolates of A. alternata.The tangerine pathotype of Alternaria alternata is the aetiological agent of Alternaria brown spot on tangerines. In the state of Paraíba, Brazil, its occurrence on “Dancy” tangerine trees is associated with genetic aspects as well as the influence of environmental conditions on reproduction and dissemination within and between populations. The aim of the present study was to evaluate the diversity of isolates of this pathogen using morphophysiological and molecular markers. For the analysis of mycelial growth and sporulation, 30 isolates from different locations were examined at 24-hour intervals until the seventh day, when the spores were quantified. The 30 isolates were characterised based on molecular markers (ISSR) and genetic similarity (Jaccard index). A factor arrangement was used: 30 isolates, four media (ODA, PDA, LEA and V8), three light regimes (continuous dark, alternating light and continuous light) and three temperatures (15°C, 25°C and 35°C), with 12 repetitions. Groups 1, 2 and 3 presented low genetic variability. Group 4 showed high genetic variability of the isolates obtained from the Massaranduba (state of Paraíba-Brazil) producing region and higher mycelial growth and sporulation of A. alternata. The continuous light regime and the temperature 25°C in PDA and V8 media were the ideal conditions for the mycelial growth and sporulation, respectively, of the isolates of A. alternata.

关 键 词：Citrus tangerine Alternaria Brown Spot Fungal Variability Environment Factors ISSR Markers 

分 类 号：R73[医药卫生—肿瘤]