Departamento de Fitotecnia e Fitossanidade, Universidade Federal do Paraná, Rua dos Funcionários 1540, CEP 80035-050, Curitiba, PR, Brazil.
Department of Plant Pathology, University of California - Davis/Kearney Agricultural Research and Extension Center, 9240 S. Riverbend Ave., Parlier, CA, 93648, USA.
Fungal Biol. 2022 Mar;126(3):235-249. doi: 10.1016/j.funbio.2021.12.003. Epub 2021 Dec 15.
Persimmon (Diospyros kaki) anthracnose is a major threat in production areas worldwide. Most of the studies are focused on Colletotrichum horii, but other species have been reported as well. The association of distinct Colletotrichum species present in Brazilian persimmon production regions as well as their host ranges are yet elusive. The aims of this work were to identify and characterize Colletotrichum species associated with the persimmon anthracnose. In a survey performed in four production regions of Brazil, 88.7% and 11.3% out of 231 isolates were identified as members of Colletotrichum gloeosporioides species complex (Cgc) or Colletotrichum acutatum species complex (Cac), respectively. A subset of 18 isolates were identified through multilocus phylogenetic analysis, using ITS-rDNA region and two loci, namely GAPDH and TUB2. This study revealed the presence of four species: C. horii (38.8%) and Colletotrichum fructicola (27.7%) from the Cgc and Colletotrichum nymphaeae (27.7%) and Colletotrichum melonis (5.8%), from the Cac. Additionally, 13 isolates were selected for morphological, physiological, and pathogenic analyses. Contrasting characteristics were observed among species of the Cgc and Cac complexes. The optimal temperature for mycelial growth and germination were higher for Cgc species. The percentage of appressoria melanisation also varied across complexes. All the identified species were able to cause anthracnose-like symptoms on persimmon fruit, leaves, shoots, and sepals. Colletotrichum species from persimmon were also able to infect apple and pear. The findings will support decisions to manage anthracnose of persimmon under high infection risk due to multiple host susceptibility.
柿炭疽病是世界范围内主要的生产威胁。大多数研究都集中在胶孢炭疽菌上,但也有报道称其他物种也是如此。巴西柿生产区不同的炭疽菌物种的关联及其宿主范围尚不清楚。本工作的目的是鉴定和表征与柿炭疽病相关的炭疽菌。在巴西四个生产区进行的一项调查中,231 个分离物中有 88.7%和 11.3%分别被鉴定为胶孢炭疽菌种复合体(Cgc)或尖孢炭疽菌种复合体(Cac)的成员。通过使用 ITS-rDNA 区域和两个基因座,即 GAPDH 和 TUB2 的多基因座系统发育分析,确定了 18 个分离物的子集。本研究揭示了四种物种的存在:来自 Cgc 的胶孢炭疽菌(38.8%)和果实炭疽菌(27.7%),以及来自 Cac 的新月炭疽菌(27.7%)和甜瓜炭疽菌(5.8%)。此外,还选择了 13 个分离物进行形态学、生理学和致病性分析。Cgc 和 Cac 复合体中的物种表现出不同的特征。最适菌丝生长和萌发温度较高的是 Cgc 种。附着胞黑化的比例也因复合体而异。鉴定出的所有物种都能够在柿果实、叶片、嫩枝和萼片上引起炭疽病样症状。柿炭疽菌还能够感染苹果和梨。这些发现将支持在高感染风险下管理柿炭疽病的决策,因为多种宿主易感性。